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Full text of "Federal motor vehicle safety standards and regulations, with amendments and interpretations"

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PREAMBLE TO AMENDMENT TO PART 571 
FEDERAL MOTOR VEHICLE SAFETY STANDARDS 

Subpart A — General 
(Docket No. 78-13; Notice 2) 



Action: Final rule. 



Summary: The purpose of this notice is to 
amend the definition of "designated seating po- 
sition" (49 CFR 571.3) to clarify that the tenn 
includes any position likely to be used for seating 
accommodation while the vehicle is in motion. 
This amendment is based on a notice of proposed 
rulemaking issued September 21, 1978 (43 FR 
44556). Dimensional parameters are specified in 
the amended definition to ensure proper and con- 
sistent designations of seating positions. This 
clarification is intended to ensure that all posi- 
tions likely to be used for seating accommodation 
will be equipped with occupant restraint systems 
for the protection of the persons using those 
positions and to ensure that vehicles are safely 
designed to accommodate their actual occupant 
capacity. 

Effective date: September 1, 1980. 

Addresses: Any petitions for reconsideration 
should refer to the docket number and notice 
number and be submitted t-o: Docket Section, 
Room 5108— Nassif Building, 400 Seventh Street, 
S.W., Washington, D.C. 20590. 

For further information contact : 

Guy Hunter, Office of Vehicle Safety Stand- 
ards, National Highway Traffic Safety 
Administration, Washington, D.C. 20590 
(202-426-2265). 

Supplementary inform/ition : Safety Standard 
No. 208 (49 CFR 571.208) requires manufac- 
turers to provide occupant crash protection for 
each "designated seating position" in motor ve- 
hicles. That term is defined in 49 CFR 571.3 as : 



"[A]ny plan view location intended by the 
manufacturer to provide seating accommoda- 
tion while the vehicle is in motion, for a 
person at least as large as a fifth percentile 
adult female, except auxiliary seating accom- 
modations such as temporary or folding jump 
seats." 

(Note: "plan view" means an overhead view 
looking down) 

Last year, the NHTSA published a notification 
to vehicle manufacturers concerning the agency's 
interpretation of the term "designated seating 
position", because of concern that certain recent 
vehicle models have improperly designated seat- 
ing capacities (43 FR 21893, May 22, 1978). The 
front or rear seats in these models have been 
designated by their manufacturers as having only 
two seating positions even though the seats are 
clearly capable of accommodating three adult oc- 
cupants and are being so used. This, of course, 
represents a safety threat to the center-seat pas- 
senger since no restraint system is provided. 
These designations are not only improper but 
also inconsistent with other designations because 
the manufacturers designate other models with 
equivalent seating space as having three positions 
and provide three sets of restraint systems. 

The earlier notification emphasized that al- 
though it is the manufacturer which designates 
the mniiber of seating positions under the current 
definition, the manufacturer's intent will be de- 
termined by the agency on the basis of all facts 
and his declarations of intent will not be accepted 
by the agency if they are inconsistent with the 



PART 571— PRE 43 



actual vehicle design. NHTSA letters of inter- 
pretation have always emphasized that the manu- 
facturer's designation must be made in gootl faith 
and nmst conform to the basic policies and tenor 
of the National Traffic and Motor Vehicle Safety 
Act (15 U.S.C. 1381, et seq.). 

Manufacturers' coumients to the notification 
led the agency to issue a proposal to amend the 
definition of "designated seating position" to pro- 
vide an adequate number of occupant restraints, 
to secure greater consistency in the seating ca- 
pacity designations by the manufacturers, and to 
assure consumers contemplating buying a new 
vehicle that comparable vehicle sizes are similarly 
designated (43 FR 44556, September 28, 1978). 
As pointed out in the pi'oposal, an investigation 
of the criteria used by manufacturers to desig- 
nate seating capacities of current motlels indicates 
that manufacturers' designations often involve 
many purely marketing considerations. The pro- 
posal cited the example of one manufacturer that 
stated to the agency it changed the front and 
rear seating configuration on one of its models 
from 3 front-2 back to 2 front/3 back (number 
of positions) because competitive cars with simi- 
lar dimensions for front-seat shoulder and hip 
room were being designated with only two front 
seat positions. This designation change was made 
even though the front and rear seats remained 
virtually the same in terms of available seating 
space. 

Manufacturers have pointed to seat width, hip 
room, shoulder room, leg room, seat trim and 
seat padding among other things to demonstrate 
their "intent" concerning the number of positions 
that should be used for seating accommodation. 
For example, even though a particular model 
might have sufficient hip room for three adult 
passengers, the manufacturer points to seat trim 
and lack of comparable padding in the center 
position as evidence that the manufacturer does 
not intend for that position to be used. As noted 
in the proposal, however, this reasoning does not 
take into account the realities of the vehicle's 
actual use and what the manufacturer can expect 
if he has provided sufficient room for a third 
passenger, even if the center position is not as 
comfortable as the two outside seat positions. 
If there is sufficient space on a bench or split 
bench seat for a center seat passenger, and no 



rigid obstruction such as a console, it must be 
said that the manufacturer "intended" that space 
to be used as a seating position, since the center 
position will likely be used by a substantial num- 
ber of persons. 

In order to clarify the existing definition of 
"designated seating position" and to codify the 
agency's interpretations of that definition, the 
previous notice proposed to amend the definition 
as follows to remove refeience to the manufac- 
turer's "intent" and to specify dimensional cri- 
teria to assure proper and consistent designations 
of seating capacity : 

" 'Designated seating position' means any 
plan view location capable of accommodating 
a person at least as large as a 5th percentile 
adult female, if tlie overall seat configuration 
and design and vehicle design is such that 
the position is likely to be used as a seating 
position while the vehicle is in motion, ex- 
cept foi' auxiliar}' seating accommodations 
such as temporary or folding jump seats. 
Any bench or split-bench seat in a passenger 
car, truck, or multipurpose passenger vehicle 
with a GVWR less than 10,000 pounds, hav- 
ing greater than 50 inches of hip space sliall 
have not less tiian tliree designated seating 
positions." 

The agency has analyzed and given due con- 
sideration to the twenty-one comments that were 
received from interested persons concerning the 
proposed amendment of "designated seating po- 
sition". All conunents have been considei"ed. 
Several motlifications of the amended definition 
have been made in response to those comments. 
The great majority of comments did not disagree 
with the intended purpose of the proposed amend- 
ment. For example. General Motors Corporation 
stated that it does not oppose the concept that a 
vehicle manufacturer should provide occupant 
restraint systems for persons wiio use the seating 
accommodations provided in the \'ehicle. 

American Motoi"s Corporation did question the 
need for a revision of the definition and stated 
that the proposal contained "only unsubstantiated 
allegations of improper designation of seating 
positions''. In response to this comment, the 
agency is placing in the public docket a copy of 
tlie ^fotor Vehicle Manufacturers Association 



PART 571— PRE 44 



PREAMBLE TO AMENDMENT TO PART 571 
FEDERAL MOTOR VEHICLE SAFETY STANDARDS 

Subpart A — General 

(Docket No. 78-13; Notice 2) 



Action: Final rule. 



Summary: The purpose of this notice is to 
amend the definition of "designated seating po- 
sition" (49 CFR 571.3) to clarify that the term 
includes any position likely to be used for seating 
accommodation while the vehicle is in motion. 
This amendment is based on a notice of proposed 
rulemaking issued September 21, 1978 (43 FR 
44556). Dimensional parameters are specified in 
the amended definition to ensure proper and con- 
sistent designations of seating positions. This 
clarification is intended to ensure that all posi- 
tions likely to be used for seating accommodation 
will be equipped with occupant restraint systems 
for the protection of the persons using those 
positions and to ensure that vehicles are safely 
designed to accommodate their actual occupant 
capacity. 

Elective date: September 1, 1980. 

Addresses: Any petitions for reconsideration 
should refer to the docket number and notice 
number and be submitted to: Docket Section, 
Room 5108 — Nassif Building, 400 Seventh Street. 
S.W., Washington, D.C. 20590. 

For further information contact : 

Guy Hunter, Office of Vehicle Safety Stand- 
ards, National Highway Traffic Safety 
Administration, Washington, D.C. 20590 
(202-426-2265). 

Supplementary information: Safety Standard 
No. 208 (49 CFR 571.208) requires manufac- 
turers to provide occupant crash protection for 
each "designated seating position" in motor ve- 
hicles. That term is defined in 49 CFR 571.3 as : 



"[A]ny plan view location intended by the 
manufacturer to provide seating accommoda- 
tion while the vehicle is in motion, for a 
person at least as large as a fifth percentile 
adult female, except auxiliai-y seating accom- 
modations such as temporary' or folding jump 
seats." 

(Note: "plan view" means an ov^erhead view 
looking down) 

Last year, the NHTSA published a notification 
to vehicle manufacturers concerning the agency's 
interpretation of the term "designated seating 
position", because of concern that certain recent 
vehicle models have improperly designated seat- 
ing capacities (43 FR 21893, May 22, 1978). The 
front or rear seats in these models have been 
designated by their manufacturers as having only 
two seating positions even though the seats are 
clearly capable of accommodating three adult oc- 
cupants and are being so used. This, of course, 
represents a safety threat to the center-seat pas- 
senger since no restraint system is provide^!. 
These designations are not only improper but 
also inconsistent with other designations because 
the manufacturers designate other models with 
equivalent seating space as having three positions 
and provide three sets of restraint systems. 

The earlier notification emphasized that al- 
though it is the manufacturer which designates 
the number of seating positions imder the current 
definition, the manufacturers intent will be de- 
termined by the agency on the basis of all facts 
and his declarations of intent will not be accepted 
by the agency if they are inconsistent with the 



PART 571— PRE 43 



actual vehicle design. NHTSA letters of inter- 
pretation have always emphasized that the manu- 
facturer's designation must be made in good faith 
and must conform to the basic policies and tenor 
of the National Traffic and Motor Vehicle Safety 
Act (15 U.S.C. 1381, et seq.). 

Manufacturers' comments to the notification 
led the agency to issue a proposal to amend the 
definition of "designated seating position" to pro- 
vide an adequate number of occupant restraints, 
to secure greater consistency in the seating ca- 
pacity designations by the manufacturers, and to 
assure consumers contemplating buying a new 
vehicle that comparable vehicle sizes are similarly 
designated (43 FR 44556, September 28, 1978). 
As pointed out in the proposal, an investigation 
of the criteria used by manufacturere to desig- 
nate seating capacities of current models indicates 
that manufacturers' designations often involve 
many purely marketing considerations. The pro- 
posal cited the example of one manufacturer that 
stated to the agency it changed the front and 
rear seating configuration on one of its models 
from 3 front-2 back to 2 front/3 back (number 
of positions) because competitive cars with simi- 
lar dimensions for front-seat shoulder and hip 
room were being designated with only two front 
seat positions. This designation change was made 
even though the front and rear seats remained 
virtually the same in terms of available seating 
space. 

Manufacturers have pointed to seat width, hip 
room, shoulder room, leg room, seat trim and 
seat padding among other things to demonstrate 
their "intent" concerning the number of positions 
that should be used for seating acconunodation. 
For example, even though a particular model 
might have sufficient hip room for three adult 
passengers, the manufacturer points to seat trim 
and lack of comparable padding in the center 
position as evidence that the manufacturer does 
not intend for that position to be used. As noted 
in the proposal, however, this reasoning does not 
take into account the realities of the vehicle's 
actual use and what the manufacturer can expect 
if he has provided sufficient room for a third 
passenger, even if the center position is not as 
comfortable as the two outside seat positions. 
If there is sufficient space on a bench or split 
bench seat for a center seat passenger, and no 



rigid obstruction such as a console, it must be 
said that the manufacturer "intended" that space 
to be used as a seating position, since the center 
position will likely be used by a substantial num- 
ber of persons. 

In order to clarify the existing definition of 
"designated seating position" and to codify the 
agency's interpretations of that definition, the 
previous notice proposed to amend the definition 
as follows to remove reference to the manufac- 
turer's "intent" and to specify dimensional cri- 
teria to assure pi-oper and consistent designations 
of seating capacity: 

" 'Designated seating position" means any 
plan view location capable of accommodating 
a person at least as large as a 5th percentile 
adult female, if the overall seat configuration 
and design and vehicle design is such that 
the position is likely to be used as a seating 
position while the vehicle is in motion, ex- 
cept for auxiliary seating accommodations 
such as temporary or folding jump seats. 
Any bench or split-bencli seat in a passenger 
car, truck, or multipurpose passenger vehicle 
with a GT\VR less than 10,000 pounds, liav- 
ing greater than 50 inches of hip space shall 
have not less than three designated seating 
positions." 

The agency has analyzed and given due con- 
sideration to the twenty-one comments that were 
received from interested persons concerning the 
proposed amendment of "designated seating po- 
sition". All conunents have been considered. 
Several modifications of the amendetl definition 
liave been made in response to those comments. 
The great majority of conunents did not disagree 
with the intended purpose of tlie proposed amend- 
ment. For example. General Motors Corporation 
stated that it does not oppose the concept that a 
vehicle manufacturer should provide occupant 
restraint systems for persons who use the seating 
accommodations provided in the veliicle. 

American Motoi"s Corporation did question the 
need for a revision of the definition and stated 
that the proposal contained "only unsubstantiated 
allegations of improper designation of seating 
positions". In response to this comment, the 
agency is placing in the public docket a copy of 
the Motor Vehicle Manufacturers Association 



PART 571— PRE 44 



specifications for various 1978 and 1979 model 
vehicles. These data list vehicle models and 
specify their hip-room and the number of posi- 
tions currently designated by manufacturers. 
These specifications demonstrate the inconsisten- 
cies in many current designations and illustrate 
that bench and split-bench seats in some vehicle 
models have only two designated seating posi- 
tions even though a similar vehicle model of the 
same make has three designated positions with 
less seating space. 

Neither American Motors nor any other com- 
menter refuted the fact that there are many 
vehicle models with usable center seats that are 
not designated as "seating positions". However, 
American Motors charged that the proposal only 
contained "baseless assertions of the NHTSA's 
perception of real-world uses of center front 
seating positions". It is the NHTSA's position 
that every center seating position that is likely 
to be used should be equipped with a restraint 
system regardless of the overall statistical rate 
of use of center positions, since every potential 
occupant should be afforded protection in the 
event of a vehicle crash. The existing definition 
of "designated seating position" is based on this 
premise. The agency is, however, placing copies 
of vehicle accident statistics in the docket which 
show that the number of center-seat passengers 
in motor vehicles and the number of center-seat 
fatalities and injuries is substantial. Data from 
the NHTSA's Fatal Accident Reporting System 
show that in 1977, 588 front center-seat passengers 
and 365 rear center-seat passengers were killed 
in vehicle accidents. Further, the use rate of 
center-seat positions will be affected by the future 
design of vehicles. Therefore, the clarified defi- 
nition of "designated seating position" will en- 
sure that future designs do not encourage center- 
seat use unless occupant crash protection is 
afforded those positions. 

While the majority of comments agreed with 
the concept of the proposed change, there were 
numerous complaints about the language of the 
proposed definition. Several commenters ob- 
jected to the phrase, "the position is likely to be 
used as a seating position", arguing that the 
word "likely" is subjective. Holiday Rambler 
Corporation stated that neither the manufacturer 
nor NHTSA can reasonably anticipate where 



occupants of a vehicle are likely to sit while the 
vehicle is in motion, as vehicles are often subject 
to misuse or abuse by their occupants. Other 
commenters stated that manufacturers would not 
be certain their determination of "likely use" 
would be the same as the agency's determination. 

The agency does not agree that the definition 
is subjective, since the definition does not only 
provide that any position likely to be use^ is a 
designated seating position, it also provides the 
criteria for making that determination. Those 
criteria relate to vehicle design and the overall 
seat configuration. Further, the amended defini- 
tion is more objective than the existing definition 
which is based on manufacturer's intent, which 
has not given rise to any complaints of sub- 
jectivity. NHTSA interpretations have empha- 
sized that "intent" does not mean that manufac- 
turers have "carte blanche" to designate seating 
capacities, but rather, that the manufacturer's 
intent is determined by the seat configuration 
and vehicle design. 

International Harvester suggested that the 
word "likely" be dropped from the definition 
and that the phrase "/s to be used as a seating 
position" be substituted. The agency does not 
believe this would be a meaningful change, how- 
ever, since the manufacturer's determination 
would still be based on the particular vehicle 
design and seat configuration. Further, the word 
"likely" indicates that the use must be more than 
minimal or chance use. As noted by General 
Motors, Webster's New World Dictionary defines 
the word "likely" to mean probable or fairly 
certain. In response to Holiday Rambler's com- 
ment, the agency notes that the word "likely" 
relieves manufacturers of the responsibility of 
providing for abusive or unorthodox use of a 
particular position in a motor vehicle. For ex- 
ample, people would not "likely" sit on a rigid 
console even though a few individuals might mis- 
use this position from time to time. Under the 
definition, a manufacturer would not be required 
to consider the console as a designated seating 
position. 

General Motors suggested that the same phrase 
be changed to read, "Likely to be used by a sub- 
stantial number of people". However, the agency 
believes that such a change is unnecessary for 



I 



PART 571— PRE 45 



the reasons set forth in the immediately preced- 
ing paragraph. 

Rover Triumph recommended that the phrase 
be changed to read, "any plan view location 
provided with an upholstered seat and backrest 
capable of accommodating a person at least as 
large as a 5th percentile adult female". The 
agency believes that such a change would be un- 
duly stringent, however, since the overall vehicle 
design would not be considered in determining 
designated seating capacity under such a defini- 
tion. There may be some locations capable of 
accommodating a 5th percentile female that are 
not likely to be used because of the overall vehicle 
design (a protruding dash board at the center 
position, for example). The agency has con- 
cluded that any definition of "designated seating 
position" must necessarily be subjective to a cer- 
tain extent, to avoid being too restrictive or 
harsh on manufacturers. 

The proposed definition change of "designated 
seating position" included the following caveat 
to ensure proper and consistent designations of 
seating capacity : 

". . . Any bench or split-bench seat in a pas- 
senger car, truck or multipurpose passenger 
vehicle with a GVWR less than 10,000 
pounds, having greater than 50 inches of hip 
space shall have not less than three desig- 
nated seating positions." 

There were numerous comments concerning 
this caveat. Nissan, Toyota, Toyo Kogyo, and 
Mercedes-Benz pointed out that the caveat speci- 
fies no procedure for measuring hip room, and 
suggested that the SAE Standard JllOO(a) pro- 
cedure be used. The NHTSA agrees that a 
procedure should be specified and intended for 
the measurement to be according to the SAE 
Standard JllOO(a). This is the same procedure 
used in the regulations of the Environmental 
Protection Agency for providing fuel economy 
information for comparable vehicles. Accord- 
ingly, that procedure is included in the caveat as 
set forth in this notice. Also, in response to a 
comment by General Motors the phrase "hip 
space" is changed to read "hip room", to cor- 
respond with the language of SAE Standard 
JllOO(a). 



Many commenters stated that "hip room" 
should not be the only determinative factor in 
the caveat. Commenters argued that shoulder 
room, leg room, head clearance, and other factors 
should also be considered in determining the 
number of designated seating positions on a bench 
or split-bench seat. Ford Motor Company stated 
that hip room is not as useful a decriptor as 
shoulder room in determining the number of po- 
sitions that can be used. Ford stated that a hip 
room of 51.1 inches and a shoulder room of 53.8 
inches are required to seat side-by-side three per- 
sons of randomly selected sizes at least 50 percent 
of the time. Volkswagen and Toyota also dis- 
agreed with the hip-room criteria and argued 
that the driver must be afforded more room for 
safe and comfortable operation of the veliicle 
than is provided if a 50-inch hip room criteria 
is used without also specifying shoulder room. 

The NHTSA agrees that shoulder room, leg 
room, and head clearance are factoi-s whicli may 
influence the number of persons who will use a 
bench or split-bench seat. However, the agency 
has concluded that hip room is the primary fac- 
tor that determines the number of persons who 
will likely use a seat. Also, data obtained from 
the Motor Vehicle Manufacturers Association 
indicates that the vast majority of vehicles have 
more shoulder room than hip i-oom. Thus, a 
vehicle that has 50 inches of hip room will nearly 
always have at least 50 inches of shoulder room 
and in all probability more than 50 inches of 
shoulder room. The shoulder width of a 5th 
percentile adult female is 15.7 inches. Therefore, 
three occupants of that size could easily sit 
abreast on a bench or split-bench seat having 
only 50 inches of shoulder room. In setting the 
liip-room criteria in the proposed definition, the 
agency used the dimension that is approximately 
three times the width of a 16.5-inch hip, 95th 
percentile adult male (a male weighing 215 
pounds). As the agency pointed out in the pro- 
posal, this would be sufficient hip space for three 
large-size adults to sit side-by-side. In basing 
the 50-inch criteria on the 95th percentile male 
rather than on the hip width of 5th percentile 
females, the agency proposed a liberal limit on 
the manufacturer's designation of seating capac- 
ity. Fifty inches of hip space is not only ade- 
quate to sit three large-size adults side-by-side, 



PART 571— PRE 46 



specifications for various 1978 and 1979 model 
vehicles. These data list vehicle models and 
specify their hip-room and the number of posi- 
tions currently designated by manufacturers. 
These specifications demonstrate the inconsisten- 
cies in many current designations and illustrate 
that bench and split-bench seats in some vehicle 
models have only two designated seating posi- 
tions even though a similar vehicle model of the 
same make has three designated positions with 
less seating space. 

Neither American Motors nor any other com- 
menter refuted the fact that there are many 
vehicle models with usable center seats that are 
not designated as "seating positions". However, 
American Motors charged that the pi'oposal only 
contained "baseless assertions of the NHTSA's 
perception of real-world uses of center front 
seating positions". It is the NHTSA's position 
that every center seating position that is likely 
to be used should be equipped with a restraint 
system regardless of the overall statistical rate 
of use of center positions, since every potential 
occupant should be afforded protection in the 
event of a vehicle crash. The existing definition 
of "designated seating position" is based on this 
k premise. The agency is, however, placing copies 
of vehicle accident statistics in the docket which 
show that the number of center-seat passengers 
in motor vehicles and the number of c«nter-seat 
fatalities and injuries is substantial. Data from 
the NHTSA's Fatal Accident Reporting System 
show that in 1977, 588 front center-seat passengers 
and 365 rear center-seat passengers were killed 
in vehicle accidents. Further, the use rate of 
center-seat positions will be affected by the future 
design of vehicles. Therefore, the clarified defi- 
nition of "designated seating position" will en- 
sure that future designs do not encourage center- 
seat use unless occupant crash protection is 
afforded those positions. 

While the majority of comments agreed with 
the concept of the proposed change, there were 
numerous complaints about the language of the 
proposed definition. Several conrnientei'S ob- 
jected to the phrase, "the position is likely to be 
used as a seating position", arguing that the 
word "likely" is subjective. Holiday Rambler 
Corporation stated that neither the manufacturer 
nor NHTSA can reasonably anticipate where 



occupants of a vehicle are likely to sit while the 
vehicle is in motion, as vehicles are often subject 
to misuse or abuse by their occupants. Other 
commenters stated that manufacturers would not 
be certain their determination of "likely use" 
would be the same as the agency's determination. 

The agency does not agree that the definition 
is subjective, since the definition does not only 
provide that any position likely to be used is a 
designated seating position, it also provides the 
criteria for making that determination. Those 
criteria relate to vehicle design and the overall 
seat configuration. Further, the amended defini- 
tion is more objective than the existing definition 
which is based on manufacturer's intent, which 
has not given rise to any complaints of sub- 
jectivity. NHTSA interpretations have empha- 
sized that "intent" does not mean that manufac- 
turers have "carte blanche" to designate seating 
capacities, but rather, that the manufacturer's 
intent is determined by the seat configuration 
and vehicle design. 

International Harvester suggested that the 
word "likely" be dropped from the definition 
and that the phrase "is to be used as a seating 
position" be substituted. The agency does not 
believe this would be a meaningful change, how- 
ever, since the manufacturer's determination 
would still be based on the particular veMcle 
design and seat configuration. Further, the word 
"likely" indicates that the use must be more than 
minimal or chance use. As noted by General 
Motors, Webster's New World Dictionary defines 
the word "likely" to mean probable or fairly 
certain. In response to Holidaj' Rambler's com- 
ment, the agency notes that the word "likely" 
relieves manufacturers of the responsibility of 
providing for abusive or unorthodox use of a 
particular position in a motor vehicle. For ex- 
ample, people would not "likely" sit on a rigid 
console even though a few individuals might mis- 
use this position from time to time. Under the 
definition, a manufacturer would not be required 
to consider the console as a designated seating 
position. 

General Motors suggested that the same phrase 
be changed to read, "Likely to be used by a sub- 
stantial number of people". However, the agency 
believes that such a change is unnecessary for 



i 



PART 571— PRE 45 



as the agency noted in the preamble of the pro- 
posal. Therefore, the space occupied by a rigid 
console or a fixed, stationary armrest, for ex- 
ample, would not be considered hip room and 
would not be included in the measurement of the 
50-inch limitation. This does not mean, however, 
that small, upholstered elevations or depressions 
in a bench seat should not be included in the 
measurement since these designs do not impede 
the use of center positions. To be excepted from 
the measurement there would have to be an ob- 
vious obstruction or impediment to sitting in the 
position, such that the position is obviously not 
intended to be used as a seat. A movable armrest 
that can be raised to the seat back would not 
constitute an impediment to use of the position. 
Likewise, the presence of a floor gear-shift lever 
would not normally be sufficient to discourage or 
make use of a center position on a bench seat 
impossible, even if the bench seat has a slightly 
indented contour for the sliift lever. However, 
there could conceivably be a veliicle design in 
which the lever would constitute an impediment 
to sitting (if the lever extends to within a few 
inches of the seat back, for example) . Regarding 
"integral occupant restraint mountings or hard- 
ware", if there is greater than 50 inches of hip 
room on the bench or split-bench seat there gen- 
erally must be three designated seating positions, 
and the hardware will be situated in a manner 
not to create an impediment to seating. If no 
padding or upholstei-y is provided on the seat 
and if no back rest is provided, it is not likely 
that the position would be used and the agency 
would not include the space in measurement of 
hip room. Also, if there is a movable armrest 
that can be lifted to substitute as a backrest that 
position on the bench seat would likely be used 
and the space would be included in the measure- 
ment of hip room. 

Fiat and several other commenters requested 
that the meaning of bench seat and split-bench 
seat be defined, one requesting that a definition 
be included. Fiat requested, specifically, that the 
agency specify that if a central armrest is pi'o- 
vided a seat should not be considered a "bench" 
seat. The agency does not believe it is necessai-y 
to add a definition of "bench" and "split-bench" 
seat to the definition of "designated seating posi- 
tion". Bench and split-bench seats are seats 



other than conventional bucket seats. Bucket 
seats are separated by a substantial amount of 
space and are two distinct seats. Split-bench 
seats are generally separated, if at all, only 
slightly to the extent necessai-y for independent 
movement of the separate portions. Therefore, 
any seat design having gi-eater than 50 inches of 
continuous liip room, even if intemipted slightly 
to allow independent movement of separate por- 
tions, would be considered a bench or split-bench 
seat and would have to have three designated 
seating positions. 

In order to respond to the concerns of Fiat, 
Ford, and other commenters, the agency has de- 
termined that the caveat should be changed to 
clarify that if rigid obstructions or other designs 
preclude the use of the center position, that posi- 
tion need not be designated as a seating position 
and, therefore, need not be equipped with re- 
straints regardless of the overall width of the 
seat. Therefore, the caveat as issued in this 
notice includes the phrase, "unless the seat design 
or vehicle design is such that the center position 
cannot be used for seating." This exception to 
the caveat would include, for example, a bench 
seat having greater than 50 inches of actual hip 
space if the vehicle's design is such that the dash 
board at the center position, extends out to near 
the seat back, precluding use of the seat 
space. Likewise, the exception would include a 
fixed armrest or a rigid, fxed console located in 
the center of the bench or split-bench seat. 

General Motors requested that the 50-inch 
caveat be modified to allow only two designated 
seating positions in vehicles having bench or 
split-bench seats equipped with passive seat belts 
at the outboard positions. General Motors stated 
that the proposed definition would preclude the 
use of passiA'e belts in full-size cars equipped 
witli bench seats, presumably because there are 
currently no designs for center-position passive 
belts. General Slotoi-s argued that bench seats 
are somewhat cheaper tlian bucket seats, and that 
passengers are not likely to crawl under the out- 
side passive belt to occupy the center position. 
The agency does not agree that the center posi- 
tion of a bench seat equipped with passive belts 
would not be used. If there is sufficient space on 
a bench or split-bench for three passengei-s, a 
substantial number of persons are likely to use 



PART 671— PRE 48 



but more than adequate to sit random size riders 
side-by-side, particularly if one of the occupants 
is a child. If one of the occupants is smaller 
than a 95th percentile male, shoulder room would 
be more than ample if the hip room is greater 
than 50 inches. In either case, there would be 
more than ample room for the driver to comfort- 
ably and safely operate the vehicle. 

The agency has concluded that manufacturers 
must assume that three persons will likely use a 
bench or split-bench seat if there is over 50 inches 
of usable hip room. The agency rejects Ford's 
recommendation that the criteria be 51.1 inches 
of hip room, since Ford offers no data to indicate 
50 inches is an unrealistic limit. We do note, 
however, that one current Ford model has a 
front bench seat with 55.9 inches of hip room 
and yet only two designated seating positions. 

The agency has concluded that the addition of 
a shoulder room or leg room specification in the 
caveat is an unnecessary complication of the cri- 
teria since the 50 inch hip room specification is a 
liberal limit on manufacturers' discretion in this 
area. The Australian Design Rule No. 5A is 
more stringent. It specifies that, in the case of 
bench seats, the number of seating positions shall 
be the number of complete multiples of 16 inches. 
Therefore, under the Australian iiile three posi- 
tions are required to be designated if a bench 
seat has only 48 inches of hip room. 

Toyo Kogyo questioned whether, in the case of 
hip room less than 50 inches, designating only 
two seating positions is "unconditionally per- 
mitted." The notice proposing this amendment 
stated that the 50-inch specification does not 
mean that some vehicle seats with less than 50 
inches of hip space should not also have more 
than two designated seating positions, if the ve- 
hicle and seat design is such that three positions 
would likely be used. It was pointed out that 
the specification is merely the amount of space 
the agency will consider as conclusive evidence 
that there should be at least three designated 
seating positions. These statements are not in- 
tended to imply that the agency would require 
seating position designations for each space 
capable of accommodating a 5th percentile female 
if the overall vehicle design and seat configura- 
tion is such that three positions would not likely 



be used. However, the seat design should be such 
that it is obviously to be used by only two persons 
if the manufacturer only designates two positions. 
For further guidance, see the discussion below of 
obstructions and impediments that will affect 
designations. 

Several commenters requested other changes in 
the 50-inch hip room caveat of the proposed 
definition. American Motors stated that a speci- 
fied hip room caveat is unnecessary due to the 
first part of the proposed definition: "Given the 
fact that unless the overall vehicle/seat configura- 
tion is such that a third dsp (designated seating 
position) is impracticable, any 50-inch-wide seat 
will have the capability of accommodating at 
least three 5th percentile adult females and be so 
designated. Therefore, a specified hip space cri- 
terion of 50 inches is redundant to the first part 
of the proposed definition." "Wliile the NHTSA 
acknowledges American Motors' statement that 
any 50-inch-wide seat will have the capability 
of accommodating at least three occupants, the 
agency does not agree that such a seat would 
always be designated as having three positions 
if the caveat were not present. Past industry 
practice in some cases supports this conclusion, 
as evidenced, for example, by American Motors' 
1977 "Pacer" model vehicle, which has 55.8 inches 
of hip room in the front seat, yet only two desig- 
nated seating positions. As the agency stated in 
the notice proposing this amendment, the caveat 
is intended to emphasize the amount of space the 
agency will consider as conclusive evidence that 
there should be at least three designated seating 
positions. 

Ford Motor Company stated that the caveat, 
as proposed, implies that vehicles with bench or 
split-bench seats having over 50 inches of hip 
room must have three designated seating posi- 
tions, "regardless of the existence of impediments 
such as consoles, shift levers, fixed arm rests, 
trays, integral occupant restraint mountings or 
hardware, hard unsprung or unupholstered sur- 
faces, or center depressions or elevations." Ford 
suggested that any limiting caveat be accom- 
panied with the provision that it is "applicable 
only to seating obviously designed for three or 
more occupants." The NHTSA, of course, did 
not intend for the definition to imply that a rigid 
console should be considered a seating position, 



PART 571— PRE 47 



as the agency noted in the preamble of the pro- 
posal. Therefore, the space occupied by a rigid 
console or a fixed, stationary armrest, for ex- 
ample, would not be considered hip room and 
would not be included in the measurement of the 
50-inch limitation. This does not mean, however, 
that small, upholstered elevations or depressions 
in a bench seat should not be included in the 
measurement since these designs do not impede 
the use of center positions. To be excepted from 
the measurement there would have to be an ob- 
vious obstruction or impediment to sitting in the 
position, such that the position is obviously not 
intended to be used as a seat. A movable annrest 
that can be raised to the seat back would not 
constitute an impediment to use of the position. 
Likewise, the presence of a floor gear-shift lever 
would not nonnally be sufficient to discourage or 
make use of a center position on a bench seat 
impossible, even if the bench seat has a slightly 
indented contour for the shift lever. However, 
there could conceivably be a vehicle design in 
which the lever would constitute an impediment 
to sitting (if the lever extends to within a few 
inches of the seat back, for example) . Regarding 
"integral occupant restraint mountings or hard- 
ware", if there is greater than 50 inches of hip 
room on the bench or split-bench seat there gen- 
erally must be three designated seating positions, 
and the hardware will be situated in a manner 
not to create an impediment to seating. If no 
padding or upholstery is provided on the seat 
and if no back rest is provided, it is not likely 
that the position would be used and the agency 
would not include the space in measurement of 
hip room. Also, if there is a movable armrest 
that can be lifted to substitute as a backrest that 
position on the bench seat would likely be used 
and the space would be included in the measure- 
ment of hip room. 

Fiat and several other commenters requested 
that the meaning of bench seat and split-bench 
seat be defined, one requesting that a definition 
be included. Fiat requested, specifically, that the 
agency specify that if a central armrest is pro- 
vided a seat should not be considered a "bench" 
seat. The agency does not believe it is necessary 
to add a definition of "bench" and "split-bench" 
seat to the definition of "designated seating posi- 
tion". Bench and split-bench seats are seats 



other than conventional bucket seats. Bucket 
seats are separated by a substantial amount of 
space and are two distinct seats. Split-bench 
seats are generally separated, if at all, only 
slightly to the extent necessary for independent 
movement of the separate portions. Therefore, 
any seat design having greater than 50 inches of 
continuous hip room, even if interrupted slightly 
to allow independent movement of separate por- 
tions, would be considered a bench or split-bench 
seat and would have to have three designated 
seating positions. 

In order to respond to the concerns of Fiat, 
Ford, and other commenters, the agency has de- 
termined that the caveat should be changed to 
clarify that if rigid obstructions or other designs 
preclude the use of the center position, that posi- 
tion need not be designated as a seating position 
and, therefore, need not be equipped with re- 
straints regardless of the overall width of the 
seat. Therefore, the caveat as issued in tliis 
notice includes the phrase, "unless the seat design 
or vehicle design is such that the center position 
cannot be used for seating." This exception to 
the caveat would include, for example, a bench 
seat having greater than 50 inches of actual hip 
space if the vehicle's design is such that the dash 
board at the center position, extends out to near 
the seat back, precluding use of the seat 
space. Likewise, the exception would include a 
fixed armrest or a rigid, fxed console located in 
the center of the bench or split-bench seat. 

General Motors requested that the 50-inch 
caveat be modified to allow only two designated 
seating positions in vehicles having bench or 
split-bench seats equipped with passive seat belts 
at the outboard positions. General Motors stated 
that the proposed definition would preclude the 
use of passive belts in full-size cars equipped 
with bench seats, presumably because there are 
currently no designs for center-position passive 
belts. General Motors argued that bench seats 
are somewhat cheaper than bucket seats, and that 
passengers are not likely to crawl under the out- 
side passive belt to occupy the center position. 
The agency does not agree that the center posi- 
tion of a bench seat equipped with passive belts 
would not be used. If there is sufficient space on 
a bench or split-bench for three passengers, a 
substantial number of persons are likely to use 



PART 571— PRE 48 



the center position, even if the seat has passive 
belts. Passengers could move around the passive 
belt to gain access to the center position and 
parents could easily place children in such posi- 
tions. Further, there is a good possibility that 
the exception requested by General Motors would 
lead to defeat of passive belts so that the center 
position could be used more conveniently. While 
the agency is sympathetic with the marketing 
and cost concerns of manufacturers, we believe 
there are alternatives which will ensure the 
safety of the motoring public. As General 
Motors stated in its comments, a vehicle's design 
can "make the two passenger designation more 
clear". For example, a manufacturer that wishes 
to use bench seats in vehicles equipped with pas- 
sive belts can include a fixed armrest in the 
center position of the bench seat to emphasize 
that the location is not a seating position. As 
just noted, the definition set forth in this notice 
makes clear that such a center position need not 
be designated as a seating position. It could 
be argued that parents may also sit children on 
fixed consoles, but manufacturers will not be 
held responsible, with respect to designating a 
seating position, for abusive or unlikely use of 
their vehicles. 

Nissan Motor Company requested that the 
NHTSA examine the "cost/benefit" concerns of 
requiring three seating positions for rear seats 
having greater than 50 inches of hip room. 
Nissan is currently designating only two seating 
positions in the rear seat of its Datsun models 
and is concerned that the new definition will re- 
quire the addition of a third seat belt in the rear 
seat and an upgrading of the braking perform- 
ance of those vehicles. Nissan stated that it 
assumes there is little possibility that three pas- 
sengers occupy rear seats. 

After considering Nissan's comments and re- 
viewing data concerning the use of the center 
position in rear seats, the agency has concluded 
that rear seats should not be excluded from the 
50-inch hip room caveat in the definition of 
"designated seating position". While it may be 
true that, statistically, fewer persons use the 
center rear seating position than use the center 
front seating position, there are substantial 
numbers who do use the rear position. As men- 
tioned earlier, the agency believes that all pas- 



sengers should be provided with a restraint 
system for occupant crash protection. If a rear 
seat has greater than 50 inches of unobstructed 
hip room, that seat is likely to be used by three 
passengers and the third passenger should be pro- 
tected. If a manufacturer chooses to use a large 
rear seat and wishes to designate only two posi- 
tions, it must design the seat for only two pas- 
sengers. This too can be accomplished by the 
installation of a fixed armrest or other impedi- 
ment to use of the center position. 

General Motors, American Motors, and Aston 
Martin Lagonda challenged NHTSA's statement 
in the proposal preceding this amendment that 
the changed definition will have no inflationary 
impact. The manufacturers state that they will 
be forced to make changes in seat design, to in- 
stall additional restraint systems, and to upgrade 
braking and other systems due to increased 
weight if the existing definition is altered. They 
charged that the cost of these changes will have 
a definite inflationary impact. The agency 
cannot agree with these statements. The 
amended definition is a clarification of the exist- 
ing definition and a codification of its interpre- 
tation, and does not create a "demonstrably more 
stringent standard" as stated by General Motors. 
As pointed out by the agency in the earlier 
"Notification to Manufacturers", manufacturers 
have improperly and inconsistently designated 
seating capacity on some vehicles and failed to 
comply with the existing definition of "desig- 
nated seating position" and its interpretations. 
Manufacturers have failed to designate positions 
in their vehicles that were obviously intended 
to be used for seating while the vehicle is in 
motion, as demonstrated by vehicle and seat 
design and by designations in comparable ve- 
hicle models. While the agency acknowledges 
that there will be costs associated with modi- 
fications that will have to be made on some 
veliicles, these costs will be the result of bring- 
ing vehicles into compliance with an existing 
standard. When the agency requires a recall 
campaign for noncompliance with a Federal 
safety standard there are, of course, often tre- 
mendous cost impacts on manufacturers. This 
does not mean, however, that the agency action 
is inflationary rulemaking. Further, the past 
failure of the NHTSA to adequately enforce 



PAKT 571— PRE 49 



standards dependent on the definition of "desig- 
nated seating position" does not preclude clarifi- 
cation of how that definition will effect enforce- 
ment of those standards in the future. 

The amended definition issued today does not 
require manufacturers to use any particular ve- 
hicle design or seat configuration or, for example, 
to upgrade braking performance levels. Manu- 
facturers are free to use any seat configuration 
they choose, just as they are free to build any 
size car they desire, with any materials they 
desire. The definition does not require the use 
of more costly bucket seats. The definition does 
provide, however, that if a manufacturer chooses 
to use a bench seat or a split-bench seat, it shall 
designate the number of seating positions that 
seat actually contains. This has been the require- 
ment since the definition was first issued. If 
a manufacturer "intends" for a position to be 
used he should provide restraints and ensure 
that the other vehicle systems are safely con- 
structed to accommodate the passenger weight 
capacity. The inclusion of the phrase "likely 
to be used" in the amended definition does not 
change the requirement or add subjectivity to 
the requirement. If a manufacturer does not 
intend for a position to be used, the design of 
the vehicle should be such that this is obvious 
to vehicle users. If the design of a seat posi- 
tion is such that it obviously was not intended 
for use, it will not "likely be used". Manufac- 
turers can easily manifest their true intent by 
installing stationary or fixed armrests. Manu- 
facturers should, therefore, have no problem 
unless they, in fact, want to market the vehicle 
with a bench seat capable of seating three per- 
sons, yet designate only two seating positions. 

Ford Motor Company expressed concern about 
the application of the proposed new definition 
to vehicles exceeding 10,000 pounds GVWR. 
Ford stated that the definition appears to be 
based on 5th percentile adult female accommoda- 
tion and that this could require four sets of 
belts in some of its large trucks having bench 
seats with over 58 inches of hip room. The new 
definition specifies that any plan view location 
capable of accommodating a person at least as 
large as a 5th percentile adult female will be 
considered a designated seating position if the 
overall seat configuration and design and vehicle 



design is such that the position is likely to be 
used as a seating position while the vehicle is 
in motion. In the case of large tractor-trailer 
type vehicles greatly over 10,000 pounds GVWK, 
the overall vehicle design is not such that four 
persons would likely use a bench seat. These 
large vehicles are primarily cargo-carrying ve- 
hicles, not passenger-carrying vehicles. There- 
fore, the agency would not consider the provision 
of four seating positions to be necessary or within 
the meaning of the phrase "likely to be used", 
found in the definition. It was for this reason 
that the definition's caveat requiring three seat- 
ing positions for bench seats having over 50 
inches of hip room was limited to vehicles under 
10,000 pounds GVWK. 

Holiday Rambler Corporation objected to the 
application of the proposed new definition of 
"designated seating position" to motor homes. 
Holiday pointed out that motor homes are 
designed to provide accommodations and ac- 
couterments for purposes other than transpor- 
tation, such as sleeping. Holiday stated that 
the proposed definition would require many re- 
straint systems in locations not required by the 
current defijiition. The agency finds no merit 
in Holiday's arguments since the effect of the 
amended definition as applied to motor homes 
is exactly the same as the existing definition. 
Motor home manufacturers are currently re- 
quired to designate as a seating position any 
location intended by the manufacturer to pro- 
vide seating accommodation while the vehicle is 
in motion. As has been repeatedly pointed out 
in past interpretations of this definition, a manu- 
facturer's intent will be determined by the agency 
on the basis of all facts, and the manufacturer's 
declarations will not always be accepted by the 
agency if they are inconsistent with actual ve- 
hicle design. The amended definition clarifies 
and codifies this interpretation by removing 
reference to the manufacturer's intent and em- 
phasizing that any position likely to be used 
while the vehicle is in motion will be considered 
a designated seating position. Whether a seat 
will "likely be used while the vehicle is in 
motion" will be determined by the seat configura- 
tion and design and by the vehicle design. 

The agency is currently investigating noncom- 
pliance with the existing definition of "desig- 



PART 571— PRE 50 



the center position, even if the seat has passive 
belts. Passengei-s could move around the passive 
belt to gain access to the center position and 
parents could easily place children in such posi- 
tions. Further, there is a good possibility that 
the exception requested by General Motors would 
lead to defeat of passive belts so that the center 
position could be used more convenient!}'. While 
the agency is sympathetic with the marketing 
and cost concerns of manufacturers, we believe 
there are alternatives which will ensure the 
safety of the motoring public. As General 
Motors stated in its comments, a vehicle's design 
can "make the two passenger designation more 
clear". For example, a manufacturer that wishes 
to use bench seats in vehicles equipped with pas- 
sive belts can include a fixed armrest in the 
center position of the bench seat to emphasize 
that the location is not a seating position. As 
just noted, the definition set forth in this notice 
makes clear that such a center position need not 
be designated as a seating position. It could 
be argued that parents may also sit children on 
fixed consoles, but manufactui'ers will not be 
held responsible, with respect to designating a 
seating position, for abusive or unlikely use of 
their vehicles. 

Nissan Motor Company requested that the 
NHTSA examine the "cost/benefit" concerns of 
requiring three seating positions for rear seats 
having greater than 50 inches of hip room. 
Nissan is currently designating only two seating 
positions in the rear seat of its Datsun models 
and is concerned that the new definition will re- 
quire the addition of a third seat belt in the rear 
seat and an upgrading of the braking perfonn- 
ance of those vehicles. Nissan stated that it 
assumes there is little possibility that three pas- 
sengers occupy rear seats. 

After considering Nissan's comments and re- 
viewing data concerning the use of the center 
position in rear seats, the agency has concluded 
that rear seats should not be excluded from the 
50-inch hip room caveat in the definition of 
"designated seating position". "Wliile it may be 
true that, statistically, fewer persons use the 
center rear seating position than use the center 
front seating position, there are substantial 
numbei-s who do use the rear position. As men- 
tioned earlier, the agency believes that all pas- 



sengers should be provided with a restraint 
system for occupant crash protection. If a rear 
seat has greater than 50 inches of unobstructed 
hip room, that seat is likely to be used by three 
passengers and the third passenger should be pro- 
tected. If a manufacturer chooses to use a large 
rear seat and wishes to designate only two posi- 
tions, it must design the seat for only two pas- 
sengers. This too can be accomplished by the 
installation of a fixed armrest or otlier impedi- 
ment to use of tlie center position. 

General Motors, American Motors, and Aston 
Martin Lagonda challenged NHTSA's statement 
in the proposal preceding this amendment that 
the changed definition will have no inflationary 
impact. The manufacturers state that they will 
be forced to make changes in seat design, to in- 
stall additional restraint systems, and to upgrade 
braking and other systems due to increased 
weight if the existing definition is altered. They 
charged that the cost of the,se changes will have 
a definite inflationary impact. The agency 
cannot agree with these statements. The 
amended definition is a clarification of the exist- 
ing definition and a codification of its interpre- 
tation, and does not create a "demonstrably more 
stringent standard" as stated by General Motors. 
As pointed out by the agency in the earlier 
"Notification to Manufacturers", manufacturei's 
have improperly and inconsistently designated 
seating capacity on some vehicles and failed to 
comply with the existing definition of "desig- 
nated seating position" and its interpretations. 
Manufacturers have failed to designate positions 
in their vehicles that were obviously intended 
to be used for seating while the vehicle is in 
motion, as demonstrated by vehicle and seat 
design and by designations in comparable ve- 
hicle models. AATiile the agency acknowledges 
that there will be costs associated with modi- 
fications that will have to be made on some 
vehicles, these costs will be the result of bring- 
ing vehicles into compliance with an existing 
standard. Wlien the agency requires a recall 
campaign for noncompliance with a Federal 
safety standard there are, of course, often tre- 
mendous cost impacts on manufacturers. This 
does not mean, however, that the agency action 
is inflationary rulemaking. Further, the past 
failure of the NHTSA to adequately' enforce 



PAET 571— PRE 49 



standards dependent on the definition of "desig- 
nated seating position" does not preclude clarifi- 
cation of how that definition will effect enforce- 
ment of those standards in the future. 

The amended definition issued today does not 
require manufacturers to use any particular ve- 
hicle design or seat configuration or, for example, 
to upgrade braking performance levels. Manu- 
facturers are free to use any seat configuration 
they choose, just as they are free to build any 
size car they desire, with any materials they 
desire. The definition does not require the use 
of more costly bucket seats. The definition does 
provide, however, that if a manufacturer chooses 
to use a bench seat or a split-bench seat, it shall 
designate the number of seating positions that 
seat actually contains. This has been the require- 
ment since the definition was first issued. If 
a manufacturer "intends" for a position to be 
used he should provide restraints and ensure 
that the other vehicle systems are safely con- 
structed to accommodate the passenger weight 
capacity. The inclusion of the phrase "likely 
to be used" in the amended definition does not 
change the requirement or add subjectivity to 
the requirement. If a manufacturer does not 
intend for a position to be used, the design of 
the vehicle should be such that this is obvious 
to vehicle users. If the design of a seat posi- 
tion is such that it obviously Avas not intended 
for use, it will not "likely be used". Manufac- 
turers can easily manifest their true intent by 
installing stationary or fixed armrests. Manu- 
facturers should, therefore, have no problem 
unless they, in fact, want to market the vehicle 
with a bench seat capable of seating three per- 
sons, yet designate only two seating positions. 

Ford Motor Company expressed concern about 
the application of the proposed new definition 
to vehicles exceeding 10,000 pounds GVWR. 
Ford stated that the definition appears to be 
based on 5th percentile adult female accommoda- 
tion and that this could require four sets of 
belts in some of its large trucks having bench 
seats with over 58 inches of hip room. The new 
definition specifies that any plan view location 
capable of accommodating a person at least as 
large as a 5th percentile adult female will be 
considered a designated seating position if the 
overall seat configuration and design and vehicle 



design is such that the position is likely to be 
used as a seating position while the vehicle is 
in motion. In the case of large tractor-trailer 
type vehicles greatly over 10,000 pounds GVWR, 
the overall vehicle design is not such that four 
persons would likely use a bench seat. These 
large vehicles are primarily cargo-carrying ve- 
hicles, not passenger-carrying vehicles. There- 
foi-e, the agency would not consider the provision 
of four seating positions to be necessary or within 
the meaning of the phrase "likely to be used", 
found in the definition. It was for this reason 
that the definition's caveat requiring three seat- 
ing positions for bench seats having over 50 
inches of hip room was limited to vehicles under 
10,000 pounds GVWR. 

Holiday Rambler Corporation objected to the 
application of the proposed new definition of 
"designated seating position" to motor homes. 
Holiday pointed out that motor homes are 
designed to provide accommodations and ac- 
couterments for purposes other than transpor- 
tation, such as sleeping. Holiday stated that 
the proposed definition would require many re- 
straint systems in locations not required by the 
current definition. The agency finds no merit 
in Holiday's arguments since the effect of the 
amended definition as applied to motor homes 
is exactly the same as the existing definition. 
Motor home manufacturers are currently re- 
quired to designate as a seating position any 
location intended by the manufacturer to pro- 
vide seating accommodation while the vehicle is 
in motion. As has been repeatedly pointed out 
in past interpretations of this definition, a manu- 
facturer's intent will be determined by the agency 
on the basis of all facts, and the manufacturer's 
declarations will not always be accepted by the 
agency if they are inconsistent with actual ve- 
hicle design. The amended definition clarifies 
and codifies this interpretation by removing 
reference to the manufacturer's intent and em- 
phasizing that any position likely to be used 
while the vehicle is in motion will be considered 
a designated seating position. Whether a seat 
will "likely be used while the vehicle is in 
motion" will be determined by the seat configura- 
tion and design and by the vehicle design. 

The agency is currently investigating noncom- 
pliance with the existing definition of "desig- 



PART 571— PRE 50 



nated seating position" in certain motor homes. 
These motor homes have seating positions that 
were obviously intended for use while the vehicle 
is in motion, yet the seats are not equipped with 
restraint systems and do not comply with Safety 
Standard No. 207, Seating Systems (49 CFR 
571.207). Manufacturers of these motor homes 
have abused the meaning of the phrase "intended 
by the manufacturer" and placed labels on the 
seats stating that they are not intended for use 
while the vehicle is in motion, even though the 
manufacturers know the seats will in fact be 
used. These abuses primarily involve seats at 
the front driving portion of the vehicles, not 
seats in the rear of the vehicle that are present 
for living accommodation when the vehicle is 
stationary. One model under investigation ha? 
four pedestal seats at the front driving portion 
of the vehicle, yet only the front two seats are 
designated as seating positions. It is the agency's 
position that a manufacturer must provide desig- 
nated seating positions for the number of persons 
it advertises its vehicle will accommodate. In 
the case of a motor home, this means that if 
such a vehicle is advertised to "sleep six," the 
manufacturer must assume that the six per.sons 
will ride in the vehicle to their sleeping destina- 
tion and thus must designate six seating posi- 
tions. These persons should have the benefit of 
occupant restraint systems and seats that meet 
the crashworthiness performance requirements of 
Safety Standard No. 207. It is the agency's 
position further that generally all seats in the 
front driving area of a motor home must be 
among the designated seating positions since 
those seats are the ones most likely to be occupied 
while the vehicle is in motion. For example, if 
a motor home is advertised as sleeping six per- 
sons and has four pedestal seats in the front 
driving area and several additional seats in the 
rear living accommodation area, the four pedestal 
seats and two of the seats in the rear area must be 
designated as seating positions. 

The notice proposing this amendment of the 
definition of "designated seating position" speci- 
fied an effective date for the proposed change 
of September 1, 1979. Nearly all commenters 
requested that the effective date of any amend- 
ment of the definition be delayed until September 



1, 1980, or one year after the issuance of a final 
inile and coincident with the beginning of a 
model year. Manufacturers stated that this time 
would be necessary to make modifications to some 
of their models and would reduce the cost of 
these modifications. The agency has determined 
that these requests have merit since many manu- 
facturers have already completed vehicle designs 
for their 1980 models, and since the additional 
period would minimize the cost of bringing their 
vehicles into compliance with the existing and 
amended definition of "designated seating posi- 
tion". Accordingly, the agency will not enforce 
the 50-inch hip room caveat of the new definition 
until September 1, 1980. This grace period prior 
to enforcement of the caveat does not mean, 
liowever, that the agency will not enforce the 
general provisions of the definition prior to that 
date, in cases in which a manufacturer has failed 
to designate a seat that was ob\'iously intended 
for use while the vehicle is in motion and will 
likely be so used. General Motors' request that 
the effective date of any amendment be phased-in 
with the upcoming passive restraint requirements 
is hereby denied. The additional one year period 
specified in this notice should be ample to allow 
manufacturers to make any necessarv modifica- 
tions. 

The agency has determined that this rule- 
making has no significant economic or environ- 
mental impacts, since it clarifies the existing 
definition and its interpretations. However, the 
agency is placing in the public docket an evalua- 
tion discussing the vehicles that are currently 
not in compliance with the existing definition and 
discussing the costs manufacturers might liave to 
incur to bring all of their vehicle models into 
compliance with the existing and clarified defini- 
tion of "designated seating position". 

The engineer and lawyer primarily responsible 
for the development of this notice are Guy 
Hunter and Hugh Gates. 

In consideration of the foregoing, the defini- 
tion of "designated seating position" as specified 
in 49 CFR 571.3 is amended to read as follows: 

"Designated seating position means any plan 
view location capable of accommodating a 
person at least as large as a 5th percentile 
atlult female, if the overall seat configura- 



PART 571— PRE 51 



tion and design and vehicle design is such unless the seat design or vehicle design is 

that the position is likely to be used as a such that the center position cannot be used 

seating position while the vehicle is in mo- for seating." 

tion, except for auxiliary seating accom- ,^, ,/,o i-.r> n i t nn ^n» o/^ o^ ^ «/^o /^^ 

, ,. ^ , , •' ir ,j- (Sec. 103, 119, Pub. L. 89-563, 80 Stat. 708 (15 

modations such as temporary or foldmg tV o .n io«^ Ia^^^ i i .■ - ,, •■ , 

, . , , ^ 1 ,. u I ^ U.S.C. 1392, 1407), delegation of authority at 

jump seats. Any bench or split-bench seat .^ r^r^-o -, c:r^ \ 

, , ,,. 49 (_/r ±4 1.50.) 

in a passenger car, truck or multipurpose ' 

passenger vehicle with a GVWR less than ^^^^ ^^ ^P^"!^ 12, 1979. 

10,000 pounds, having greater than 50 inches Joan Claybrook 

of hip room (measured in accordance with Administrator 

SAE Standard JllOO(a)) shall have not 44 p.R. 23229 

less than three designated seating positions, April 19, 1979 



PART 571— PRE 52 i 



nated seating position" in certain motor homes. 
These motor homes have seating positions that 
were obviously intended for use while the vehicle 
is in motion, yet the seats are not equipped with 
restraint systems and do not comply with Safety 
Standard No. 207, Seating Systems (49 CFR 
571.207). Manufacturers of these motor homes 
have abused the meaning of the phrase "intended 
by the manufacturer" and placed labels on the 
seats stating that they are not intended for use 
while the vehicle is in motion, even though the 
manufacturers know the seats will in fact be 
used. These abuses primarily involve seats at 
the front driving portion of the vehicles, not 
seats in the rear of the vehicle that are present 
for living accommodation when the vehicle is 
stationary. One model under investigation has 
four pedestal seats at the front driving portion 
of the vehicle, yet only the front two seats are 
designated as seating positions. It is the agency's 
position that a manufacturer must provide desig- 
nated seating positions for the number of persons 
it advertises its vehicle will accommodate. In 
the case of a motor home, this means that if 
such a vehicle is advertised to "sleep six," the 
manufacturer must assume that the six persons 
will ride in the vehicle to their sleeping destina- 
tion and thus must designate six seating posi- 
tions. These persons should have the benefit of 
occupant restraint systems and seats that meet 
the crashworthiness performance requirements of 
Safety Standard No. 207. It is the agency's 
position further that generally all seats in the 
front driving area of a motor home must be 
among the designated seating positions since 
those seats are the ones most likely to be occupied 
while the vehicle is in motion. For example, if 
a motor home is advertised as sleeping six per- 
sons and has four pedestal seats in the front 
driving area and several additional seats in the 
rear living accommodation area, the four pedestal 
seats and two of the seats in the rear area must be 
designated as seating positions. 

The notice proposing this amendment of the 
definition of "designated seating position" speci- 
fied an effective date for the proposed change 
of September 1, 1979. Nearly all commenters 
requested that the effective date of any amend- 
ment of the definition be delayed until September 



1, 1980, or one year after the issuance of a final 
i-ule and coincident with the beginning of a 
model year. Manufacturers stated that this time 
would be necessary to make modifications to some 
of their models and would reduce the cost of 
these modifications. The agency has determined 
that these requests have merit since many manu- 
facturers have already completed vehicle designs 
for their 1980 models, and since the additional 
period would minimize the cost of bringing their 
vehicles into compliance with the existing and 
amended definition of "designated seating posi- 
tion". Accordingly, the agency will not enforce 
the 50-inch hip room caveat of the new definition 
until September 1, 1980. This grace period prior 
to enforcement of the caveat does not mean, 
however, that the agency will not enforce the 
general provisions of the definition prior to that 
date, in cases in which a manufacturer has failed 
to designate a seat that was obviously intended 
for use while the vehicle is in motion and will 
likely be so used. General Motors' request that 
the effective date of any amendment be phased-in 
with the upcoming passive restraint requirements 
is hereby denied. The additional one year period 
specified in this notice should be ample to allow 
manufacturers to make any necessary modifica- 
tions. 

The agency has determined that this rule- 
making has no significant economic or environ- 
mental impacts, since it clarifies the existing 
definition and its interpretations. However, the 
agency is placing in the public docket an evalua- 
tion discussing the vehicles that are currently 
not in compliance with the existing definition and 
discussing the costs manufacturers might have to 
incur to bring all of their vehicle models into 
compliance with the existing and clarified defini- 
tion of "designated seating position". 

The engineer and lawyer primarily responsible 
for the development of this notice are Guy 
Hunter and Hugh Oates. 

In consideration of the foregoing, the defini- 
tion of "designated seating position" as specified 
in 49 CFR 571.3 is amended to read as follows: 

"Designated seating position means any plan 
view location capable of accommodating a 
person at least as large as a 5th percentile 
adult female, if the overall seat configura- 



PART 571— PRE 51 



tion and design and vehicle design is such unless the seat design or vehicle design is 

that the position is likely to be used as a such that the center position cannot be used 

seating position while the vehicle is in mo- for seating." 

tion except for auxiliary seating accom- ^^3 ^^^ ^ ^ ^^ ^^^^ ^^^ 

modations such as temporary or foldmg ^g^ ^3 delegation of authority at 

jump seats. Any bench or split-bench seat pfp 1 fin \ 

in a passenger car, truck or multipurpose ' "' 

passenger vehicle with a GVWK less than ^^""^ '''' ^P"l l^, 1979. 

10,000 pounds, having greater than 50 inches Joan Claybrook 

of hip room (measured in accordance with Administrator 

SAE Standard JllOO(a)) shall have not 44 F.R. 23229 

less than three designated seating positions, April 19, 1979 



PAKT 571— PRE 52 



PREAMBLE TO AN AMENDMENT TO PART 571 — 
FEDERAL MOTOR VEHICLE SAFETY STANDARD 

Matter Incorporated by Reference 
(Docket No. 81-14; Notice 1) 



ACTION: Final rule. 

SUMMARY: The Federal Motor Vehicle Safety 
Standards issued by NHTSA incorporate by 
reference a number of standards and test 
procedures adopted by voluntary standards 
associations, such as the American Society for 
Testing and Materials. Part 571.5 of the agency's 
regulations is the procedural rule that incorporates 
all of the materials found in the agency's safety 
standards. This notice amends the regulation to 
specify that the Director of the Federal Register 
has approved the agency's incorporations by 
reference and to announce that all the materials 
are available for inspection and copying at both 
the agency and the Office of the Federal Register. 

EFFECTIVE DATE: This amendment is effective 
March 22, 1982. 

SUPPLEMENTARY INFORMATION: The 
Federal Motor Vehicle Safety Standards issued 
by the agency incorporate by reference a number 
of standards and test procedures adopted by 
voluntary standards associations, such as the 
American Society for Testing and Materials and 
the Society of Automotive Engineers. The legal 
effect of incorporation by reference is that the 
material is treated as if it were published in full in 
the Federal Register and thus has the force and 
effect of law. The agency only uses incorporation 
by reference when the referenced material is of a 
detailed, technical nature and would unnecessarUy 
add to the volume of matter printed in the 
Federal Register. In all instances, the material 
incorporated by reference is easily available to 
the public for inspection and copying. 

In accordance with section 552(a) of the 
Administrative Procedure Act (5 U.S.C. 552(a)) and 



1 CFR Part 51, the Director of the Federal Register 
must review and approve all incorporations by 
reference before they are effective. On March 28, 
1979 (44 F.R. 18630), the Office of the Federal 
Register (OFR) established new procedures that 
agencies must follow to maintain approval from 
the Director of the Federal Register for the 
incorporation of materials by reference in the Code 
of Federal Regulations (CFR). Each agency is 
required to submit annually to the Director of the 
Federal Register a list identifying all material 
which the agency has incorporated by reference 
in the CFR. Part of the OFR's review of the list is 
a check of the incorporating language in the 
regulatory text to confirm that it meets OFR's 
drafting requirements (1 CFR Part 571.5). NHTSA 
is making several editorial changes in 49 CFR 
Part 571.5 of its regulations, which is the 
provision that incorporates by reference all of the 
material cited in the agency's safety standards, to 
conform to OFR's drafting requirements. 

This notice amends Part 571.5 to add language 
stating that the Director of the Federal Register 
has approved all of the incorporations by reference. 
In addition, the agency is amending Part 571.5 to 
state that any proposed changes to material 
incorporated by reference will be published in the 
Federal Register. When the agency has 
incorporated material by reference, it has always 
specified the precise version (i.e., date, edition, 
etc.) of the material being incorporate by 
reference. Subsequent versions of material 
incorporated by reference are not automatically 
adopted. The agency has always proposed any 
change to any incorporated material in the 
Federal Register. Part 571.5 also is amended to 
state that all of the materials incorporated by 
reference are available for inspection and copying 
both at the agency and at the Federal Register. 



PART 571; PRE 53 



The agency has determined that this 
procedural amendment is not a major rule within 
the meaning of Executive Order 12291. Likewise, 
it is not a significant rule within the meaning of 
the Department of Transportation's regulatory 
policies and procedures. The amendments made 
by this notice do not impose any substantive 
requirements or restrictions on the public. They 
merely make minor modifications in the agency's 
incorporation by reference procedure. Since the 
amendments concern a procedural matter, the 
agency is not required by the Administrative 
Procedure Act to provide notice and opportunity 
to comment on them. Because of this, the 
amendments are also not covered by the 
requirements of the Regulatory Flexibility Act. 



Since these procedural amendments are so minor 
and technical, the agency does not believe that 
any useful purpose would be served by voluntarily 
providing any opportunity to comment on them. 

Issued on February 11, 1982. 



Raymond A. Peck, Jr. 
Administrator 

47 F.R. 7253 
February 18, 1982 



PART 571; PRE 54 



PREAMBLE TO AN AMENDMENT TO PART 571 — 
FEDERAL MOTOR VEHICLE SAFETY STANDARD 

Matter Incorporated by Reference 
(Docket No. 81-14; Notice 1) 



ACTION: Final rule. 

SUMMARY: The Federal Motor Vehicle Safety 
Standards issued by NHTSA incorporate by 
reference a number of standards and test 
procedures adopted by voluntary standards 
associations, such as the American Society for 
Testing and Materials. Part 571.5 of the agency's 
regulations is the procedural rule that incorporates 
all of the materials found in the agency's safety 
standards. This notice amends the regulation to 
specify that the Director of the Federal Register 
has approved the agency's incorporations by 
reference and to announce that all the materials 
are available for inspection and copying at both 
the agency and the Office of the Federal Regis ter. 

EFFECTIVE DATE: This amendment is effective 
March 22, 1982. 

SUPPLEMENTARY INFORMATION: The 

Federal Motor Vehicle Safety Standards issued 
by the agency incorporate by reference a number 
of standards and test procedures adopted by 
voluntary standards associations, such as the 
American Society for Testing and Materials and 
the Society of Automotive Engineers. The legal 
effect of incorporation by reference is that the 
material is treated as if it were published in full in 
the Federal Register and thus has the force and 
effect of law. The agency only uses incorporation 
by reference when the referenced material is of a 
detailed, technical nature and would unnecessarUy 
add to the volume of matter printed in the 
Federal Register. In all instances, the material 
incorporated by reference is easily available to 
the public for inspection and copying. 

In accordance with section 552(a) of the 
Administrative Procedure Act (5 U.S.C. 552(a)) and 



1 CFR Part 51, the Director of the Federal Register 
must review and approve all incorporations by 
reference before they are effective. On March 28, 
1979 (44 F.R. 18630), the Office of the Federal 
Register (OFR) established new procedures that 
agencies must follow to maintain approval from 
the Director of the Federal Register for the 
incorporation of materials by reference in the Code 
of Federal Regulations (CFR). Each agency is 
required to submit annually to the Director of the 
Federal Register a list identifying all material 
which the agency has incorporated by reference 
in the CFR. Part of the OFR's review of the list is 
a check of the incorporating language in the 
regulatory text to confirm that it meets OFR's 
drafting requirements (1 CFR Part 571.5). NHTSA 
is making several editorial changes in 49 CFR 
Part 571.5 of its regulations, which is the 
provision that incorporates by reference all of the 
material cited in the agency's safety standards, to 
conform to OFR's drafting requirements. 

This notice amends Part 571.5 to add language 
stating that the Director of the Federal Register 
has approved all of the incorporations by reference. 
In addition, the agency is amending Part 571.5 to 
state that any proposed changes to material 
incorporated by reference will be published in the 
Federal Register. When the agency has 
incorporated material by reference, it has always 
specified the precise version (i.e., date, edition, 
etc.) of the material being incorporate by 
reference. Subsequent versions of material 
incorporated by reference are not automatically 
adopted. The agency has always proposed any 
change to any incorporated material in the 
Federal Register. Part 571.5 also is amended to 
state that all of the materials incorporated by 
reference are available for inspection and copying 
both at the agency and at the Federal Register. 



PART 571; PRE 53 



The agency has determined that this 
procedural amendment is not a major rule within 
the meaning of Executive Order 12291. Likewise, 
it is not a significant rule within the meaning of 
the Department of Transportation's regulatory 
policies and procedures. The amendments made 
by this notice do not impose any substantive 
requirements or restrictions on the public. They 
merely make minor modifications in the agency's 
incorporation by reference procedure. Since the 
amendments concern a procedural matter, the 
agency is not required by the Administrative 
Procedure Act to provide notice and opportunity 
to comment on them. Because of this, the 
amendments are also not covered by the 
requirements of the Regulatory Flexibility Act. 



Since these procedural amendments are so minor 
and technical, the agency does not believe that 
any useful purpose would be served by voluntarily 
providing any opportunity to comment on them. 

Issued on February 11, 1982. 



Raymond A. Peck, Jr. 
Administrator 

47 F.R. 7253 
February 18, 1982 



PART 571; PRE 54 



PART 571 -FEDERAL MOTOR VEHICLE SAFETY STANDARDS 



SUBPART A— GENERAL 

§ 571.1 Scope. 

This part contains the Federal Motor Vehicle 
Safety Standards for motor vehicles and motor 
vehicle equipment established under section 103 of 
the National Traffic and Motor Vehicle Safety Act 
of 1966 (80 Stat. 718). 

§ 571.3 Definitions. 

(a) Statutory definitions. All terms defined in 
section 102 of the Act are used in their statutory 
meaning. 

(b) Other definitions. As used in this chapter 
"Act" means the National Traffic and Motor Vehicle 
Safety Act of 1966 (80 Stat. 718). 

"Approved," unless used with reference to 
another person, means approved by the Secretary. 

"Boat trailer" means a trailer designed with 
cradle-type mountings to transport a boat and con- 
figured to permit launching of the boat from the 
rear of the trailer. 

"Bus" means a motor vehicle with motive 
power, except a trailer designed for carrying more 
than 10 persons. 

"Curb weight" means the weight of a motor 
vehicle with standard equipment: maximum 
capacity of engine fuel, oil, and coolant; and, if so 
equipped, air conditioning and additional weight 
optional engine. 

"Designated seating capacity" means the 
number of designated seating positions provided. 

"Designated seating position" means any plan 
view location capable of accommodating a person at 
least as large as a 5th percentile adult female, if the 
overall seat configuration and design and vehicle 
design is such that the position is likely to be used as 
a seating position while the vehicle is in motion, 
except for auxiliary seating accommodations such as 
temporary or folding jump seats. Any bench or split- 
bench seat in a passenger car, truck or multipurpose 
passenger vehicle with a GVWR less than 10,000 
pounds, having greater than 50 inches of hip room 
(measured in accordance with SAE Standard 
JllOO (a)) shall have not less than three designated 



seating positions, unless the seat design or vehicle 
design is such that the center position cannot be 
used for seating. 

"Driver" means the occupant of a motor vehicle 
seated immediately behind the steering control 
system. 

"Emergency brake" means a mechanism designed 
to stop a motor vehicle after a failure of the service 
brake. 

"5th percentile adult female" means a person 
possessing the dimensions and weight of the 5th 
percentile adult female specified for the total age 
group in Public Health Service Publication No. 
1000, Series 11, No. 8, "Weight, Height, and 
Selected Body Dimensions of Adults." 

"Fixed collision barrier" means a flat, vertical, 
unyielding surface with the following 
characteristics: 

(1) The surface is sufficiently large that when 
struck by a tested vehicle, no portion of the vehicle 
projects or passes beyond the surface. 

(2) The approach is a horizontal surface that is 
large enough for the vehicle to attain a stable 
attitude during its approach to the barrier, and 
that does not restrict vehicle motion during 
impact. 

(3) When struck by a vehicle, the surface and its 
supporting structure absorb no significant portion 
of the vehicle's kinetic energy, so that a perform- 
ance requirement described in terms of impact 
with a fixed collision barrier must be met no 
matter how small an amount of energy is absorbed 
by the barrier. 

"Firefighting vehicle" means a vehicle designed 
exclusively for the purpose of fighting fires. 

"Forward control" means a configuration in 
which more than half of the engine length is rear- 
ward of the foremost point of the windshield base 
and the steering wheel hub is in the forward 
quarter of the vehicle length. 

"Gross axle weight rating" or "GAWR" means 
the value specified by the vehicle manufacturer as 
the load-carrying capacity of a single axle system, 
as measured at the tire-ground interfaces. 



PART 571-1 



"Gross combination weight rating" or "GCWR" 
means the value specified by the manufacturer as 
the loaded weight of a combination vehicle. 

"Gross vehicle weight rating" or "GVWR" 
means the value specified by the manufacturer as 
the loaded weight of a single vehicle. 

"H point" means the mechanically hinged hip 
point of a manikin which simulates the actual pivot 
center of the human torso and thigh, described in 
SAE Recommended Practice J826. "Manikin for 
Use in Defining Vehicle Seating Accom- 
modations," November 1962. 

"Head impact area" means all non-glazed 
surfaces of the interior of a vehicle that are 
statically contactable by a 6.5-inch diameter 
spherical head form of a measuring device having a 
pivot point to "top-of-head" dimension infinitely 
adjustable from 29 to 33 inches in accordance with 
the following procedure, or its graphic equivalent: 

(a) At each designated seating position, place 
the pivot point of the measuring device— 

(1) For seats that are adjustable fore and aft, 
at— 

(i) The seating reference point; and 

(ii) A point 5 inches horizontally forward of 
the seating reference point and vertically 
above the seating reference point an amount 
equal to the rise which results from a 5-inch 
forward adjustment of the seat or 0.75 inches; 
and 

(2) For seats that are not adjustable fore and 
aft, at the seating reference point. 

(b) With the pivot point to "top-of-head" dimen- 
sions at each value allowed by the device and the 
interior dimensions of the vehicle, determine all 
contact points above the lower windshield glass 
line and forward of the seating reference point. 

(c) With the head form at each contact point, 
and with the device in a vertical position if no con- 
tact point exists for a particular adjusted length, 
pivot the measuring device forward and downward 
through all arcs in vertical planes to 90° each side 
of the vertical longitudinal plane through the 
seating reference point, until the head form con- 
tacts an interior surface or until it is tangent to a 
horizontal point 1 inch above the seating reference 
point, whichever occurs first. 

"Includes" means includes but is not limited to. 



"Interior compartment door" means any door in 
the interior of the vehicle installed by the manufac- 
turer as a cover for storage space normally used 
for personal effects. 

"Longitudinal" or "longitudinally" means parallel 
to the longitudinal centerline of the vehicle. 

"Motorcycle" means a motor vehicle with motive 
power having a seat or saddle for the use of the 
rider and designed to travel on not more than three 
wheels in contact with the ground. 

"Motor-driven cycle" means a motorcycle with a 
motor that produces 5-brake horsepower or less. 

"Multipurpose passenger vehicle" means a 
motor vehicle with motive power, except a trailer, 
designed to carry 10 persons or less which is con- 
structed either on a truck chassis or with special 
features for occasional off-road operation. 

"Open-body type vehicle" means a vehicle having 
no occupant compartment top or an occupant com- 
partment top that can be installed or removed by the 
user at his convenience. 

"Outboard designated seating position "means a 
designated seating position where a longitudinal 
vertical plane tangent to the outboard side of the 
seat cushion is less than 12 inches from the inner- 
most point on the inside surface of the vehicle at a 
height between the seating reference point and the 
shoulder reference point (as shown in Fig. 1 of 
Federal Motor Vehicle Safety Standard No. 210) 
and longitudinally between the front and rear 
edges of the seat cushion. 

"Overall vehicle width" means the nominal 
design dimension of the widest part of the vehicle, 
exclusive of signal lamps, marker lamps, outside 
rearview mirrors, flexible fender extensions, and 
mud flaps, determined with doors and windows 
closed and the wheels in the straight-ahead 
position. 

"Parking brake" means a mechanism designed 
to prevent the movement of a stationary motor 
vehicle. 

"Passenger car" means a motor vehicle with 
motive power, except a multipurpose passenger 
vehicle, motorcycle, or trailer designed for carry- 
ing 10 persons or less. 

"Pelvic impact area" means that area of the door 
or body side panel adjacent to any outboard 
designated seating position which is bounded by 
horizontal planes 7 inches above and 4 inches below 
the seating reference point and vertical transverse 
planes 8 inches forward and 2 inches rearward of 
the seating reference point. 



PART 571-2 



PART 571 — FEDERAL MOTOR VEHICLE SAFETY STANDARDS 



SUBPART A— GENERAL 

§ 571.1 Scope. 

This part contains the Federal Motor Vehicle 
Safety Standards for motor vehicles and motor 
vehicle equipment established under section 103 of 
the National Traffic and Motor Vehicle Safety Act 
of 1966 (80 Stat. 718). 

§ 571.3 Definitions. 

(a) Statutory definitions. All terms defined in 
section 102 of the Act are used in their statutory 
meaning. 

(b) Other definitions. As used in this chapter 
"Act" means the National Traffic and Motor Vehicle 
Safety Act of 1966 (80 Stat. 718). 

"Approved," unless used with reference to 
another person, means approved by the Secretary. 

"Boat trailer" means a trailer designed with 
cradle-type mountings to transport a boat and con- 
figured to permit launching of the boat from the 
rear of the trailer. 

"Bus" means a motor vehicle with motive 
power, except a trailer designed for carrying more 
than 10 persons. 

"Curb weight" means the weight of a motor 
vehicle with standard equipment: maximum 
capacity of engine fuel, oil, and coolant; and, if so 
equipped, air conditioning and additional weight 
optional engine. 

"Designated seating capacity" means the 
number of designated seating positions provided. 

"Designated seating position" means any plan 
view location capable of accommodating a person at 
least as large as a 5th percentile adult female, if the 
overall seat configuration and design and vehicle 
design is such that the position is likely to be used as 
a seating position while the vehicle is in motion, 
except for auxiliary seating accommodations such as 
temporary or folding jump seats. Any bench or split- 
bench seat in a passenger car, truck or multipurpose 
passenger vehicle with a GVWR less than 10,000 
pounds, having greater than 50 inches of hip room 
(measured in accordance with SAE Standard 
JllOO (a)) shall have not less than three designated 



seating positions, unless the seat design or vehicle 
design is such that the center position cannot be 
used for seating. 

"Driver" means the occupant of a motor vehicle 
seated immediately behind the steering control 
system. 

"Emergency brake" means a mechanism designed 
to stop a motor vehicle after a failure of the service 
brake. 

"5th percentile adult female" means a person 
possessing the dimensions and weight of the 5th 
percentile adult female specified for the total age 
group in Public Health Service Publication No. 
1000, Series 11, No. 8, "Weight, Height, and 
Selected Body Dimensions of Adults." 

"Fixed collision barrier" means a flat, vertical, 
unyielding surface with the following 
characteristics: 

(1) The surface is sufficiently large that when 
struck by a tested vehicle, no portion of the vehicle 
projects or passes beyond the surface. 

(2) The approach is a horizontal surface that is 
large enough for the vehicle to attain a stable 
attitude during its approach to the barrier, and 
that does not restrict vehicle motion during 
impact. 

(3) When struck by a vehicle, the surface and its 
supporting structure absorb no significant portion 
of the vehicle's kinetic energy, so that a perform- 
ance requirement described in terms of impact 
with a fixed collision barrier must be met no 
matter how small an amount of energy is absorbed 
by the barrier. 

"Firefighting vehicle" means a vehicle designed 
exclusively for the purpose of fighting fires. 

"Forward control" means a configuration in 
which more than half of the engine length is rear- 
ward of the foremost point of the windshield base 
and the steering wheel hub is in the forward 
quarter of the vehicle length. 

"Gross axle weight rating" or "GAWR" means 
the value specified by the vehicle manufacturer as 
the load-carrying capacity of a single axle system, 
as measured at the tire-ground interfaces. 



PART 571-1 



"Gross combination weight rating" or "GCWR" 
means the value specified by the manufacturer as 
the loaded weight of a combination vehicle. 

"Gross vehicle weight rating" or "GVWR" 
means the value specified by the manufacturer as 
the loaded weight of a single vehicle. 

"H point" means the mechanically hinged hip 
point of a manikin which simulates the actual pivot 
center of the human torso and thigh, described in 
SAE Recommended Practice J826. "Manikin for 
Use in Defining Vehicle Seating Accom- 
modations," November 1962. 

"Head impact area" means all non-glazed 
surfaces of the interior of a vehicle that are 
statically contactable by a 6.5-inch diameter 
spherical head form of a measuring device having a 
pivot point to "top-of-head" dimension infinitely 
adjustable from 29 to 33 inches in accordance with 
the following procedure, or its graphic equivalent: 

(a) At each designated seating position, place 
the pivot point of the measuring device— 

(1) For seats that are adjustable fore and aft, 
at- 

(i) The seating reference point; and 

(ii) A point 5 inches horizontally forward of 
the seating reference point and vertically 
above the seating reference point an amount 
equal to the rise which results from a 5-inch 
forward adjustment of the seat or 0.75 inches; 
and 

(2) For seats that are not adjustable fore and 
aft, at the seating reference point. 

(b) With the pivot point to "top-of-head" dimen- 
sions at each value allowed by the device and the 
interior dimensions of the vehicle, determine all 
contact points above the lower windshield glass 
line and forward of the seating reference point. 

(c) With the head form at each contact point, 
and with the device in a vertical position if no con- 
tact point exists for a particular adjusted length, 
pivot the measuring device forward and downward 
through all arcs in vertical planes to 90° each side 
of the vertical longitudinal plane through the 
seating reference point, until the head form con- 
tacts an interior surface or until it is tangent to a 
horizontal point 1 inch above the seating reference 
point, whichever occurs first. 

"Includes" means includes but is not limited to. 



"Interior compartment door" means any door in 
the interior of the vehicle installed by the manufac- 
turer as a cover for storage space normally used 
for personal effects. 

"Longitudinal" or "longitudinally" means parallel 
to the longitudinal centerline of the vehicle. 

"Motorcycle" means a motor vehicle with motive 
power having a seat or saddle for the use of the 
rider and designed to travel on not more than three 
wheels in contact with the ground. 

"Motor-driven cycle" means a motorcycle with a 
motor that produces 5-brake horsepower or less. 

"Multipurpose passenger vehicle" means a 
motor vehicle with motive power, except a trailer, 
designed to carry 10 persons or less which is con- 
structed either on a truck chassis or with special 
features for occasional off-road operation. 

"Open-body type vehicle" means a vehicle having 
no occupant compartment top or an occupant com- 
partment top that can be installed or removed by the 
user at his convenience. 

"Outboard designated seating position"means a 
designated seating position where a longitudinal 
vertical plane tangent to the outboard side of the 
seat cusihion is less than 12 inches from the inner- 
most point on the inside surface of the vehicle at a 
height between the seating reference point and the 
shoulder reference point (as shown in Fig. 1 of 
Federal Motor Vehicle Safety Standard No. 210) 
and longitudinally between the front and rear 
edges of the seat cushion. 

"Overall vehicle width" means the nominal 
design dimension of the widest part of the vehicle, 
exclusive of signal lamps, marker lamps, outside 
rearview mirrors, flexible fender extensions, and 
mud flaps, determined with doors and windows 
closed and the wheels in the straight-ahead 
position. 

"Parking brake" means a mechanism designed 
to prevent the movement of a stationary motor 
vehicle. 

"Passenger car" means a motor vehicle with 
motive power, except a multipurpose passenger 
vehicle, motorcycle, or trailer designed for carry- 
ing 10 persons or less. 

"Pelvic impact area" means that area of the door 
or body side panel adjacent to any outboard 
designated seating position which is bounded by 
horizontal planes 7 inches above and 4 inches below 
the seating reference point and vertical transverse 
planes 8 inches forward and 2 inches rearward of 
the seating reference point. 



PART 571-2 



"Pole trailer" means a motor vehicle without 
motive power designed to be drawn by another 
motor vehicle and attached to the towing vehicle by 
means of a reach or pole, or by being boomed or 
otherwise secured to the towing vehicle, for trans- 
porting long or irregularly shaped loads such as 
poles, pipes, or structural members capable generally 
of sustaining themselves as beams between the sup- 
porting connections. 

"School bus" means a bus that is sold, or intro 
duced in interstate commerce, for purposes that in- 
clude carrying students to and from school or 
related events, but does not include a bus designed 
and sold for operation as a common carrier in urban 
transportation. 

"Seating reference point" means the manufac- 
turer's design reference point which— 

(a) Establishes the rearmost normal design driving 
or riding position of each designated seating position 
in a vehicle; 

(b) Has coordinates established relative to the 
designed vehicle structure; 

(c) Simulates the position of the pivot center of 
the human torso and thigh; and 

(d) Is the reference point employed to position the 
two dimensional templates described in SAE Recom- 
mended Practice J826, "Manikins for Use in Defining 
Vehicle Seating Accommodations," November 1962. 

"Semitrailer" means a trailer, except a pole trailer, 
so constructed that a substantial part of its weight 
rests upon or is carried by another motor vehicle. 

"Service brake" means the primary mechanism 
designed to stop a motor vehicle. 

"Speed attainable in 1 mile" means the speed 
attainable by accelerating at maximum rate from a 
standing start for 1 mile, on a level surface. 

"Speed attainable in 2 miles" means the speed 
attainable by accelerating at a maximum rate from 
a standing start for 2 miles, on a level surface. 

"Torso line" means the line connecting the "H" 
point and the shoulder reference point as defined 
in SAE Recommended Practice J787b, "Motor 
Vehicle Seat Belt Anchorage," September 1966. 

"Trailer" means a motor vehicle with or without 
motive power, designed for carrying persons or pro- 
perty and for being drawn by another motor vehicle. 

"Trailer converter dolly" means a trailer chassis 
equipped with one or more axles, a lower half of a 
fifth wheel and a drawbar. 

"Truck" means a motor vehicle with motive 
power, except a trailer, designed primarily for the 
transportation of property or special purpose 
equipment 



"Truck tractor" means a truck designed primarily 
for drawing other motor vehicles and not so con- 
structed as to carry a load other than a part of the 
weight of the vehicle and the load so drawn. 

"Unloaded vehicle weight" means the weight of 
a vehicle with maximum capacity of all fluids 
necessary for operation of the vehicle, but without 
cargo, occupants, or accessories that are ordinarily 
removed from the vehicle when they are not in use. 

"95th percentile adult male" means a person 
possessing the dimensions and weight of the 95th 
percentile adult male specified in Public Health Serv- 
ice Publication No. 1000, Series 11, No. 8, "Weight, 
Height, and Selected Body Dimensions of Adults." 

["Vehicle fuel tank capacity" means the tank's 
unusable capacity (i.e., the volume of fuel left at 
the bottom of the tank when the vehicle's fuel 
pump can no longer draw fuel from the tank) plus 
its usable capacity (i.e., the volume of fuel that can 
be pumped into the tank through the filler pipe 
with the vehicle on a level surface and with the 
unusable capacity already in the tank). The term 
does not include the vapor volume of the tank (i.e., 
the space above the fuel tank filler neck) nor the 
volume of the fuel tank filler neck. (47 F.R. 47839- 
October 28, 1982. Effective: October 28, 1982)1 

§ 571.4 Explanation of usage. 

The word "any," used in connection with a 
range of values or set of items in the requirements, 
conditions, and procedures of the standards or 
regulations in this chapter, means generally the 
totality of the items or values, any one of which 
may be selected by the Administration for testing, 
except where clearly specified otherwise. 

Examples: "The vehicle shall meet the 
requirements of S4.1 when tested at any point 
between 18 and 22 inches above the ground." This 
means that the vehicle must be capable of meeting 
the specified requirements at every point between 
18 and 22 inches above the ground. The test in 
question for a given vehicle may call for a single 
test (a single impact, for example), but the vehicle 
must meet the requirement at whatever point the 
Administration selects, within the specified range. 

"Each tire shall be capable of meeting the 
requirements of this standard when mounted on 
any rim specified by the manufacturer as suitable 
for use with that tire." This means that, where the 
manufacturer specifies more than one rim as 
suitable for use with a tire, the tire must meet the 
requirements with whatever rim the Administra- 
tion selects from the specified group. 

"Any one of the items listed below may, at the 
option of the manufacturer, be substituted for the 
hardware specified in S4.1." Here the wording 



(Rev. 10/28/82) 



PART 571-3 



clearly indicates that the selection of items is at the 
manufacturer's option. 

§ 571.5 Matter incorporated by reference. 

(a) Incorporation. There are hereby incorpo- 
rated, by reference, into this part, all materials 
referred to in any standard in Subpart B of this 
part that are not set forth in full in the standard. 
These materials are thereby made part of this regu- 
lation. The Director of the Federal Register has ap- 
proved the materials incorporated by reference. 
For materials subject to change, only the specific 
version approved by the Director of the Federal 
Register and specified in the standard are incorpo- 
rated. A notice of any change in these materials will 
be published in the Federal Register. As a conven- 
ience to the reader, the materials incorporated by 
reference are listed in the Finding Aid Table found 
at the end of this volume of the Code of Federal 
Regulations. 

(b) Availability. The materials incorporated by 
reference, other than acts of Congress and matter 
published elsewhere in the Federal Register, are 
available as follows: 

(1) Standards of the Society of Automotive En- 
gineers (SAE). They are published by the Society of 
Automotive Engineers, Inc. Information and 
copies may be obtained by writing to: Society of 
Automotive Engineers, Inc., 400 Commonwealth 
Drive, Warrendale, Pennsylvania 15096. 

(2) Standards of the American Society for 
Testing and Matenals. They are published by the 
American Society for Testing and Materials. Infor- 
mation on copies may be obtained by writing to the 
American Society for Testing and Materials, 1916 
Race Street, Philadelphia, Pennsylvania, 19103. 

(3) Standards of the American National 
Standards Institute. They are published by the 
American National Standards Institute. Infor- 
mation and copies may be obtained by writing to: 
American National Standards Institute, 1430 
Broadway, New York, New York 10018. 

(4) Data from the National Health Sui-vey, 
Public Health Publication No. 1000, Series 11, 
No. 8. This is published by the U.S. Department 
of Health, Education, and Welfare. Copies may 
be obtained for a price of 35 cents from the 
Superintendent of Documents, U.S. Government 
Printing Office, Washington, D.C., 20402. 

[(5) Test methods of the American Association 
of Textile Cheinists and Colorists. They are pub- 
lished by the American Association of Textile 
Chemists and Colorists. Information and copies 



can be obtained by writing to: American Associa- 
tion of Textile Chemists and Colorist, Post Office 
Box 886, Durham, NC. (48 F.R. 30138-June 30, 
1983. Effective: July 30, 1983)1 

(6) All of the above materials, as well as any 
other materials incorporated by reference, are 
available for inspection and copying at the Office 
of Vehicle Safety Standards, National Highway 
Traffic Safety Administration, 400 Seventh 
Street, S.W., Washington, D.C. 20590. The 
materials are also available for inspection and 
copying at the Office of the Federal Register, 
1100 L Street, N.W., Washington, D.C. 

§ 571.7 Applicability. 

(a) General. Except as provided in paragraphs (c) 
and (d) of this section, each standard set forth in Sub- 
part B of this part applies according to its terms to all 
motor vehicles or items of motor vehicle equipment 
the manufacture of which is completed on or after 
the effective date of the standard. 

(b) Chassis-cabs. Chassis-cabs, as defined in 
371.3(b), manufactured on or after January 1, 
1968, shall meet all standards in effect on the date 
of manufacture of the chassis-cab as are applicable 
to the principal end use intended by its manufac- 
turer except that where the chassis-cab is equipped 
with only part and not all of the items of lighting 
equipment referred to in standard No. 108, it need 
not meet such standards. 

(Revoked 36 F.R. 7055. Effective: 4/14/71) 

(c) Military vehicles. No standard applies to a 
vehicle or item of equipment manufactured for, 
and sold directly to, the Armed Forces of the 
United States in conformity with contractural 
specifications. 

(d) Export. No standard applies to a vehicle or 
item of equipment in the circumstances provided in 
section 108(13) (5)of the Act(15U.S.C. 1397(b)(5)). 

(e) Combining and new used components. When a 
new cab is used in the assembly of a truck, the 
truck will be considered newly manufactured for 
purposes of paragraph (a) of this section, the 
application of the requirements of this chapter, and 
the Act, unless the engine, transmission, and drive 
axle(s) (as a minimum) of the assembled vehicle are 
not new, and at least two of these components 
were taken from the same vehicle. 

(f) Combining new and used compcments in 
trailer manufacture. When new materials are 
used in the assembly of a trailer, the trailer will be 
considered newly manufactured for purposes of 
paragraph (a) of this section, the application of the 



(Rev. 7/31/83) 



PART 571-4 



"Pole trailer" means a motor vehicle without 
motive power designed to be drawn by another 
motor vehicle and attached to the towing vehicle by 
means of a reach or pole, or by being boomed or 
otherwise secured to the towing vehicle, for trans- 
porting long or irregularly shaped loads such as 
poles, pif)es, or structural members capable generally 
of sustaining themselves as beams between the sup- 
porting connections. 

"School bus" means a bus that is sold, or intro 
duced in interstate commerce, for purposes that in- 
clude carrying students to and from school or 
related events, but does not include a bus designed 
and sold for operation as a common carrier in urban 
transportation. 

"Seating reference point" means the manufac- 
turer's design reference point which— 

(a) Establishes the rearmost normal design driving 
or riding position of each designated seating position 
in a vehicle; 

(b) Has coordinates established relative to the 
designed vehicle structure; 

(c) Simulates the position of the pivot center of 
the human torso and thigh; and 

(d) Is the reference point employed to position the 
two dimensional templates described in SAE Recom- 
mended Practice J826, "Manikins for Use in Defining 
Vehicle Seating Accommodations," November 1962. 

"Semitrailer" means a trailer, except a pole trailer, 
so constructed that a substantial part of its weight 
rests upon or is carried by another motor vehicle. 

"Service brake" means the primary mechanism 
designed to stop a motor vehicle. 

"Speed attainable in 1 mile" means the speed 
attainable by accelerating at maximum rate from a 
standing start for 1 mile, on a level surface. 

"Speed attainable in 2 miles" means the speed 
attainable by accelerating at a maximum rate from 
a standing start for 2 miles, on a level surface. 

"Torso line" means the line connecting the "H" 
point and the shoulder reference point as defined 
in SAE Recommended Practice J787b, "Motor 
Vehicle Seat Belt Anchorage," September 1966. 

"Trailer" means a motor vehicle with or without 
motive power, designed for carrying persons or pro- 
perty and for being drawn by another motor vehicle. 

"Ti-ailer converter dolly" means a trailer chassis 
equipped with one or more axles, a lower half of a 
fi-fth wheel and a drawbar. 

"Truck" means a motor vehicle with motive 
power, except a trailer, designed primarily for the 
transportation of property or special purpose 
equipment 



"Truck tractor" means a truck designed primarily 
for drawing other motor vehicles and not so con- 
structed as to carry a load other than a part of the 
weight of the vehicle and the load so drawn. 

"Unloaded vehicle weight" means the weight of 
a vehicle with maximum capacity of all fluids 
necessary for operation of the vehicle, but without 
cargo, occupants, or accessories that are ordinarily 
removed from the vehicle when they are not in use. 

"95th percentile adult male" means a person 
possessing the dimensions and weight of the 95th 
percentile adult male specified in Public Health Serv- 
ice Publication No. 1000, Series 11, No. 8, "Weight, 
Height, and Selected Body Dimensions of Adults." 

["Vehicle fuel tank capacity" means the tank's 
unusable capacity (i.e., the volume of fuel left at 
the bottom of the tank when the vehicle's fuel 
pump can no longer draw fuel from the tank) plus 
its usable capacity (i.e., the volume of fuel that can 
be pumped into the tank through the filler pipe 
with the vehicle on a level surface and with the 
unusable capacity already in the tank). The term 
does not include the vapor volume of the tank (i.e., 
the space above the fuel tank filler neck) nor the 
volume of the fuel tank filler neck. (47 F.R. 47839- 
October 28, 1982. Effective: October 28, 1982)1 

§571.4 Explanation of usage. 

The word "any," used in connection with a 
range of values or set of items in the requirements, 
conditions, and procedures of the standards or 
regulations in this chapter, means generally the 
totality of the items or values, any one of which 
may be selected by the Administration for testing, 
except where clearly specified otherwise. 

Examples: "The vehicle shall meet the 
requirements of S4.1 when tested at any point 
between 18 and 22 inches above the ground." This 
means that the vehicle must be capable of meeting 
the specified requirements at every point between 
18 and 22 inches above the ground. The test in 
question for a given vehicle may call for a single 
test (a single impact, for example), but the vehicle 
must meet the requirement at whatever point the 
Administration selects, within the specified range. 

"Each tire shall be capable of meeting the 
requirements of this standard when mounted on 
any rim specified by the manufacturer as suitable 
for use with that tire." This means that, where the 
manufacturer specifies more than one rim as 
suitable for use with a tire, the tire must meet the 
requirements with whatever rim the Administra- 
tion selects from the specified group. 

"Any one of the items listed below may, at the 
option of the manufacturer, be substituted for the 
hardware specified in S4.1." Here the wording 



(Rev. 10/28/82) 



PART 571-3 



clearly indicates that the selection of items is at the 
manufacturer's option. 

§ 571.5 Matter incorporated by reference. 

(a) Incorporation. There are hereby incorpo- 
rated, by reference, into this part, all materials 
referred to in any standard in Subpart B of this 
part that are not set forth in full in the standard. 
These materials are thereby made part of this regu- 
lation. The Director of the Federal Register has ap- 
proved the materials incorporated by reference. 
For materials subject to change, only the specific 
version approved by the Director of the Federal 
Register and specified in the standard are incorpo- 
rated. A notice of any change in these materials will 
be published in the Federal Register. As a conven- 
ience to the reader, the materials incorporated by 
reference are listed in the Finding Aid Table found 
at the end of this volume of the Code of Federal 
Regulations. 

(b) Availability. The materials incorporated by 
reference, other than acts of Congress and matter 
published elsewhere in the Federal Register, are 
available as follows: 

(1) Standards of the Society of Automotive En- 
gineers (SAE). They are published by the Society of 
Automotive Engineers, Inc. Information and 
copies may be obtained by writing to: Society of 
Automotive Engineers, Inc., 400 Commonwealth 
Drive, Warrendale, Pennsylvania 15096. 

(2) Standards of the American Society for 
Testing and Materials. They are published by the 
American Society for Testing and Materials. Infor- 
mation on copies may be obtained by writing to the 
American Society for Testing and Materials, 1916 
Race Street, Philadelphia, Pennsylvania, 19103. 

(3) Standards of the American National 
Standards Institute. They are published by the 
American National Standards Institute. Infor- 
mation and copies may be obtained by writing to: 
American National Standards Institute, 1430 
Broadway, New York, New York 10018. 

(4) Data from the National Health Survey, 
Public Health Publication. No. 1000, Series 11, 
No. 8. This is published by the U.S. Department 
of Health, Education, and Welfare. Copies may 
be obtained for a price of 35 cents from the 
Superintendent of Documents, U.S. Government 
Printing Office, Washington, D.C., 20402. 

((5) Test methods of the Avfierican Association 
of Textile Chem,ists and Colorists. They are pub- 
lished by the American Association of Textile 
Chemists and Colorists. Information and copies 



can be obtained by writing to: American Associa- 
tion of Textile Chemists and Colorist, Post Office 
Box 886, Durham, NC. (48 F.R. 30138-June 30, 
1983. Effective: July 30, 1983)1 

(6) All of the above materials, as well as any 
other materials incorporated by reference, are 
available for inspection and copying at the Office 
of Vehicle Safety Standards, National Highway 
Traffic Safety Administration, 400 Seventh 
Street, S.W., Washington, D.C. 20590. The 
materials are also available for inspection and 
copying at the Office of the Federal Register, 
1100 L Street, N.W., Washington, D.C. 

§ 571.7 Applicability. 

(a) General. Except as provided in paragraphs (c) 
and (d) of this section, each standard set forth in Sub- 
part B of this part applies according to its terms to all 
motor vehicles or items of motor vehicle equipment 
the manufacture of which is completed on or after 
the effective date of the standard. 

(b) Chassis-cabs. Chassis-cabs, as defined in 
371.3(b), manufactured on or after January 1, 
1968, shall meet all standards in effect on the date 
of manufacture of the chassis-cab as are applicable 
to the principal end use intended by its manufac- 
turer except that where the chassis-cab is equipped 
with only part and not all of the items of lightmg 
equipment referred to in standard No. 108, it need 
not meet such standards. 

(Revoked 36 F.R. 7055. Effective: 4/14/71) 

(c) Military vehicles. No standard applies to a 
vehicle or item of equipment manufactured for, 
and sold directly to, the Armed Forces of the 
United States in conformity with contractural 
specifications. 

(d) Export. No standard applies to a vehicle or 
item of equipment in the circumstances provided in 
section 108(b) (5)of the Act(15U.S.C. 1397(b) (5)). 

(e) Combining and new used components. When a 
new cab is used in the assembly of a truck, the 
truck will be considered newly manufactured for 
purposes of paragraph (a) of this section, the 
application of the requirements of this chapter, and 
the Act, unless the engine, transmission, and drive 
axle(s) (as a minimum) of the assembled vehicle are 
not new, and at least two of these components 
were taken from the same vehicle. 

(f) Combining new and used components in 
trailer manufacture. When new materials are 
used in the assembly of a trailer, the trailer will be 
considered newly manufactured for purposes of 
paragraph (a) of this section, the application of the 



(Rev. 7/31/83) 



PART 571-4 



requirements of this chapter, and the Act, unless, 
at a minimum, the trailer running gear assembly 
(axle(s), wheels, braking and suspension) is not 
new, and was taken from an existing trailer— 

(1) Whose identity is continued in the reas- 
sembled vehicle with respect to the Vehicle Iden- 
tification Number; and 

(2) That is owned or leased by the user of the 
reassembled vehicle. 

§ 571.8 Effective date. 

Notwithstanding the effective date provisions of 
the motor vehicle safety standards in this part, the 
effective date of any standard or amendment of a 
standard issued after September 1, 1971, to which 
firefighting vehicles must conform shall be, with 
respect to such vehicles, either 2 years after the 
date on which such standard or amendment is 
published in the Rules and Regulations section of 
the Federal Register, or the effective date specified 
in the notice, whichever is later, except as such 
standard or amendment may otherwise specifically 
provide with respect to firefighting vehicles. 

§ 571.9 Separability. 

If any standard established in this part or its 
application to any person or circumstance is held 
invalid, the remainder of the part and the applica- 
tion of that standard to other persons or 
circumstances is not affected thereby. 

§571.13 Labeling of chassis-cabs. 

Each chassis-cab manufactured on or after Jan- 
uary 1, 1968, shall, at the time of sale, conspicu- 
ously display a label affixed by its manufacturer 
that— 

(a) Identifies it as a chassis-cab and shows the 
date of manufacture; 

(b) Identifies the Federal motor vehicle safety 
standards with which its manufacturer states the 
chassis-cab fully complied for the principal end 
uses of such vehicle: and 

(c) States in substance that the chassis-cab may 
be used on the public highways for the purpose of 
transit between its manufacturer and subsequent 
manufacturers (including distribution incidental 
thereto) and for no other purpose, until such time 
as the chassis-cab complies with all Federal motor 
vehicle safety standards applicable to any end use 
of such vehicle. This provision does not relieve the 
manufacturer or shipper from any applicable 
requirement imposed upon such chassis-cabs by 
Federal, State, or local authority. 



Interpretations 
General. Compliance with Initial Federal Motor 
Vehicle Safety Standards is determined by actual 
date of manufacture, rather than model year 
designation. 

Mini-bikes. 

A number of persons have asked the Federal 
Highway Administrator to reconsider his February 
4, 1969 interpretation of the National Traffic and 
Motor Vehicle Safety Act of 1966 concerning mini- 
bikes. In that interpretation, the Administrator con- 
cluded that mini-bikes are "motor vehicles" within 
the meaning of section 102(3) of the Act, and are 
regarded as "motorcycles" or "motor-driven 
cycles" under the Federal Highway Administration 
regulations. Under those regulations, motorcycles 
and motor-driven cycles must conform to Motor 
Vehicle Safety Standard No. 108, which imposes 
performance requirements relating to lamps, reflec- 
tive devices, and associated equipment. 

The primary basis for the conclusion of the 
February 4 interpretation, as stated therein, was 
that "[i]n the absence of clear evidence that as a 
practical matter a vehicle is not being, or will not 
be, used on the public streets, roads, or highways 
the operating capability of a vehicle is the most 
relevant fact in determining whether or not that 
vehicle is a motor vehicle under the Act ..." It was 
stated that if examination of a vehicle's operating 
capability revealed that the vehicle is "physically 
capable (either as offered for sale or without major 
additions or modifications) of being operated on 
the public streets, roads, or highways, the vehicle 
will be considered as having been 'manufactured 
primarily for use on the public streets, roads, and 
highways'." It was also stated that a manufacturer 
would need to show substantially more than that it 
has advertised a vehicle as a recreational or private 
property vehicle or that use of the vehicle on a 
public roadway, as manufactured and sold, would 
be illegal in order to overcome a conclusion based 
on examination of the vehicle's operating capability. 

Petitioners have urged the Administrator to 
abandon the operating capability test. They have 
argued that many vehicular types, such as self- 
propelled riding mowers, have an "operating 
capability" for use on the public roads and yet are 
obviously outside the class of vehicles which 
Congress subjected to safety regulation. True as 
that may be, the Administrator has decided to 
adhere to the view that the operating capability of 
a vehicle is an important criterion in determining 



PART 571-5 



whether it is a "motor vehicle" within the meaning 
of the statute. As the above-quoted portion of the 
February 4, 1969 interpretation states, however, 
the operating capability test is not reached if there 
is "clear evidence that as a practical matter the 
vehicle is not being used on the public streets, 
roads, or highways. In the case of self-propelled 
riding mowers, golf carts, and many other similar 
self-propelled vehicles, such clear evidence exists. 

It is clear from the definition of "motor vehicle" 
in section 102(3) of the Act* that the purpose for 
which a vehicle is manufactured is a basic factor in 
determining whether it was "manufactured 
primarily for use on the public streets, roads, and 
highways." However, this does not mean that the 
proper classification of a particular vehicle is wholly 
dependent on the manufacturer's subjective state 
of mind. Instead, the Administrator intends to 
invoke the familiar principle that the purpose for 
which an act, such as the production of a vehicle, is 
undertaken may be discerned from the actor's 
conduct in the light of the surrounding 
circumstances. Thus, if a vehicle is operationally 
capable of being used on public thoroughfares and 
if in fact a substantial proportion of the consuming 
public actually uses it that way, it is a "motor 
vehicle" without regard to the manufacturer's 
intent, however manifested. In such a case, it 
would be incumbent upon a manufacturer of such a 
vehicle either to alter the vehicle's design, con- 
figuration, and equipment to render it unsuitable 
for on-road use or, by compliance with applicable 
motor vehicle safety standards, to render the vehi- 
cle safe for use on public streets, roads, and 
highways. 

In borderline cases, other factors must also be 
considered. Perhaps the most important of these is 
whether state and local laws permit the vehicle in 
question to be used and registered for use on public 
highways. The nature of the manufacturer's pro- 
motional and marketing activities is also evidence 
of the use for which the vehicle is manufactured. 
Some relevant aspects of those activities are: (1) 
whether the vehicle is advertised for on-road use or 
whether the manufacturer represents to the public 
that the vehicle is not for use on public roads; (2) 
whether the vehicle is sold through retail outlets 
that also deal in conventional motor vehicles; and 



*" 'Motor vehicle' means any vehicle driven or drawn by 
mechanical power manufactured primarily for use on the 
public streets, roads, and highways, except any vehicle 
operated exclusively on a rail or rails." 15 U.S.C. 1391(3). 



(3) whether the manufacturer affixes a label warn- 
ing owners of the vehicle not to use it for travel 
over public roads. 

In the first instance, each manufacturer must 
decide whether his vehicles are manufactured 
primarily for use on the public streets, roads, and 
highways. His decision cannot be conclusive, 
however. Under the law, the authority to deter- 
mine whether vehicles are subject to the provisions 
of the National Traffic and Motor Vehicle Safety 
Act is vested in the Secretary. As delegee of the 
Secretary, the Administrator will exercise that 
power in the light of all of the relevant facts and 
circumstances (including the manufacturer's 
declaration of his intent) with the objective of 
reducing the toll of injuries and deaths on the 
public highways. 

Analysis of the available data about mini-bikes, 
including the contents of petitions for reconsidera- 
tion of the February 4, 1969 interpretation, has 
convinced the Administrator that, for the most 
part, mini-bikes should not be considered motor 
vehicles under the above criteria. Mini-bikes do 
have an operating capability for use on public 
roads. It now appears that incidents of their actual 
operation on public streets, roads, and highways, 
while undoubtably extant, are comparatively rare. 
What is more important, their use and registration 
for use on public thoroughfares is precluded by the 
laws of virtually every jurisdiction, unless the mini- 
bike is equipped with lamps, reflective devices, and 
associated equipment of the sort that Safety 
Standard No. 108 requires. Most manufacturers of 
mini-bikes do not advertise or otherwise promote 
them as being suitable for use on public roads, and 
some actually attach a label to their vehicles, warn- 
ing against on-road use. Those manufacturers do 
not furnish retail purchasers with the documenta- 
tion needed to register, title, and license the 
vehicles for use on public roads under the relevant 
State laws. Finally, mini-bikes are commonly sold 
to the public through retail outlets that are not 
licensed dealers in motor vehicles. 

Accordingly, so long as the great majority of the 
States do not permit the registration of mini-bikes 
for use on the public highways and streets, and 
until such time as there is clear evidence that mini- 
bikes are being used on public streets to a signifi- 
cant extent, the Administrator is of the view that, 
at a minimum, persons who manufacture mini- 
bikes are not manufacturers of "motor vehicles" 
within the meaning of the National Traffic and 
Motor Vehicle Safety Act of 1966 if they (1) do not 



PART 571-6 



requirements of this chapter, and the Act, unless, 
at a minimum, the trailer running gear assembly 
(axle(s), wheels, braking and suspension) is not 
new, and was taken from an existing trailer— 

(1) Whose identity is continued in the reas- 
sembled vehicle with respect to the Vehicle Iden- 
tification Number; and 

(2) That is owned or leased by the user of the 
reassembled vehicle. 

§ 571.8 Effective date. 

Notwithstanding the effective date provisions of 
the motor vehicle safety standards in this part, the 
effective date of any standard or amendment of a 
standard issued after September 1, 1971, to which 
firefighting vehicles must conform shall be, with 
respect to such vehicles, either 2 years after the 
date on which such standard or amendment is 
published in the Rules and Regulations section of 
the Federal Register, or the effective date specified 
in the notice, whichever is later, except as such 
standard or amendment may otherwise specifically 
provide with respect to firefighting vehicles. 

§ 571.9 Separability. 

If any standard established in this part or its 
application to any person or circumstance is held 
invalid, the remainder of the part and the applica- 
tion of that standard to other persons or 
circumstances is not affected thereby. 

§571.13 Labeling of chassis-cabs. 

Each chassis-cab manufactured on or after Jan- 
uary 1, 1968, shall, at the time of sale, conspicu- 
ously display a label affixed by its manufacturer 
that- 

(a) Identifies it as a chassis-cab and shows the 
date of manufacture; 

(b) Identifies the Federal motor vehicle safety 
standards with which its manufacturer states the 
chassis-cab fully complied for the principal end 
uses of such vehicle: and 

(c) States in substance that the chassis-cab may 
be used on the public highways for the purpose of 
transit between its manufacturer and subsequent 
manufacturers (including distribution incidental 
thereto) and for no other purpose, until such time 
as the chassis-cab complies with all Federal motor 
vehicle safety standards applicable to any end use 
of such vehicle. This provision does not relieve the 
manufacturer or shipper from any applicable 
requirement imposed upon such chassis-cabs by 
Federal, State, or local authority. 



Interpretations 
General. Compliance with Initial Federal Motor 
Vehicle Safety Standards is determined by actual 
date of manufacture, rather than model year 
designation. 

Mini-bikes. 

A number of persons have asked the Federal 
Highway Administrator to reconsider his February 
4, 1969 interpretation of the National Traffic and 
Motor Vehicle Safety Act of 1966 concerning mini- 
bikes. In that interpretation, the Administrator con- 
cluded that mini-bikes are "motor vehicles" within 
the meaning of section 102(3) of the Act, and are 
regarded as "motorcycles" or "motor-driven 
cycles" under the Federal Highway Administration 
regulations. Under those regulations, motorcycles 
and motor-driven cycles must conform to Motor 
Vehicle Safety Standard No. 108, which imposes 
performance requirements relating to lamps, reflec- 
tive devices, and associated equipment. 

The primary basis for the conclusion of the 
February 4 interpretation, as stated therein, was 
that "[i]n the absence of clear evidence that as a 
practical matter a vehicle is not being, or will not 
be, used on the public streets, roads, or highways 
the operating capability of a vehicle is the most 
relevant fact in determining whether or not that 
vehicle is a motor vehicle under the Act ..." It was 
stated that if examination of a vehicle's operating 
capability revealed that the vehicle is "physically 
capable (either as offered for sale or without major 
additions or modifications) of being operated on 
the public streets, roads, or highways, the vehicle 
will be considered as having been 'manufactured 
primarily for use on the pubHc streets, roads, and 
highways'." It was also stated that a manufacturer 
would need to show substantially more than that it 
has advertised a vehicle as a recreational or private 
property vehicle or that use of the vehicle on a 
public roadway, as manufactured and sold, would 
be illegal in order to overcome a conclusion based 
on examination of the vehicle's operating capability. 

Petitioners have urged the Administrator to 
abandon the operating capability test. They have 
argued that many vehicular types, such as self- 
propelled riding mowers, have an "operating 
capability" for use on the public roads and yet are 
obviously outside the class of vehicles which 
Congress subjected to safety regulation. True as 
that may be, the Administrator has decided to 
adhere to the view that the operating capability of 
a vehicle is an important criterion in determining 



PART 571-5 



whether it is a "motor vehicle" within the meaning 
of the statute. As the above-quoted portion of the 
February 4, 1969 interpretation states, however, 
the operating capabihty test is not reached if there 
is "clear evidence that as a practical matter the 
vehicle is not being used on the public streets, 
roads, or highways. In the case of self-propelled 
riding mowers, golf carts, and many other similar 
self-propelled vehicles, such clear evidence exists. 

It is clear from the definition of "motor vehicle" 
in section 102(3) of the Act* that the purpose for 
which a vehicle is manufactured is a basic factor in 
determining whether it was "manufactured 
primarily for use on the public streets, roads, and 
highways." However, this does not mean that the 
proper classification of a particular vehicle is wholly 
dependent on the manufacturer's subjective state 
of mind. Instead, the Administrator intends to 
invoke the familiar principle that the purpose for 
which an act, such as the production of a vehicle, is 
undertaken may be discerned from the actor's 
conduct in the light of the surrounding 
circumstances. Thus, if a vehicle is operationally 
capable of being used on public thoroughfares and 
if in fact a substantial proportion of the consuming 
public actually uses it that way, it is a "motor 
vehicle" without regard to the manufacturer's 
intent, however manifested. In such a case, it 
would be incumbent upon a manufacturer of such a 
vehicle either to alter the vehicle's design, con- 
figuration, and equipment to render it unsuitable 
for on-road use or, by compliance with applicable 
motor vehicle safety standards, to render the vehi- 
cle safe for use on public streets, roads, and 
highways. 

In borderline cases, other factors must also be 
considered. Perhaps the most important of these is 
whether state and local laws permit the vehicle in 
question to be used and registered for use on public 
highways. The nature of the manufacturer's pro- 
motional and marketing activities is also evidence 
of the use for which the vehicle is manufactured. 
Some relevant aspects of those activities are: (1) 
whether the vehicle is advertised for on-road use or 
whether the manufacturer represents to the public 
that the vehicle is not for use on public roads; (2) 
whether the vehicle is sold through retail outlets 
that also deal in conventional motor vehicles; and 



*" 'Motor vehicle' means any vehicle driven or drawn by 
mechanical power manufactured primarily for use on the 
public streets, roads, and liighways, except any vehicle 
operated exclusively on a rail or rails." 15 U.S.C. 1391(3). 



(3) whether the manufacturer affixes a label warn- 
ing owners of the vehicle not to use it for travel 
over public roads. 

In the first instance, each manufacturer must 
decide whether his vehicles are manufactured 
primarily for use on the public streets, roads, and 
highways. His decision cannot be conclusive, 
however. Under the law, the authority to deter- 
mine whether vehicles are subject to the provisions 
of the National Traffic and Motor Vehicle Safety 
Act is vested in the Secretary. As delegee of the 
Secretary, the Administrator will exercise that 
power in the light of all of the relevant facts and 
circumstances (including the manufacturer's 
declaration of his intent) with the objective of 
reducing the toll of injuries and deaths on the 
public highways. 

Analysis of the available data about mini-bikes, 
including the contents of petitions for reconsidera- 
tion of the February 4, 1969 interpretation, has 
convinced the Administrator that, for the most 
part, mini-bikes should not be considered motor 
vehicles under the above criteria. Mini-bikes do 
have an operating capability for use on public 
roads. It now appears that incidents of their actual 
operation on public streets, roads, and highways, 
while undoubtably extant, are comparatively rare. 
What is more important, their use and registration , 
for use on public thoroughfares is precluded by the I 
laws of virtually every jurisdiction, unless the mini- 
bike is equipped with lamps, reflective devices, and 
associated equipment of the sort that Safety 
Standard No. 108 requires. Most manufacturers of 
mini-bikes do not advertise or otherwise promote 
them as being suitable for use on public roads, and 
some actually attach a label to their vehicles, warn- 
ing against on-road use. Those manufacturers do 
not furnish retail purchasers with the documenta- 
tion needed to register, title, and license the 
vehicles for use on public roads under the relevant 
State laws. Finally, mini-bikes are commonly sold 
to the public through retail outlets that are not 
licensed dealers in motor vehicles. 

Accordingly, so long as the great majority of the 
States do not permit the registration of mini-bikes 
for use on the public highways and streets, and 
until such time as there is clear evidence that mini- 
bikes are being used on public streets to a signifi- 
cant extent, the Administrator is of the view that, 
at a minimum, persons who manufacture mini- 
bikes are not manufacturers of "motor vehicles" 
within the meaning of the National Traffic and 
Motor Vehicle Safety Act of 1966 if they (1) do not 



PART 571-6 



equip them with devices and accessories that 
render them lawful for use and registration for use 
on public highways under state and local laws; (2) 
do not otherwise participate or assist in making 
the vehicles lawful for operation on public roads (as 
by furnishing certificates of origin or other title 
documents, unless those documents contain a 
statement that the vehicles were not manufactured 
for use on public streets, roads, or highways); (3) 
do not advertise or promote them as vehicles 
suitable for use on public roads; (4) do not generally 
market them through retail dealers on motor 
vehicles; and (5) affix to the mini-bikes a notice 
stating in substance that the vehicles were not 
manufactured for use on public streets, roads, or 
highways and warning operators against such use. 
Cases of manufacturers who fulfill some, but not 
all, of the above criteria will be dealt with 
individually under those criteria and such others as 
may be relevant. 

A manufacturer of mini-bikes is, of course, at 
liberty to design and construct his products so that 
they conform to the provisions of the motor vehicle 
safety standards that are applicable to motorcycles 
and thereby to manufacture motor vehicles within 
the meaning of the National Traffic and Motor 
Vehicle Safety Act. 

In consideration of the foregoing, the petitions 
for reconsideration of the February 4, 1969 inter- 
pretation relating to mini-bikes are granted to the 
extent set forth above, and that interpretation is 
withdrawn. 

Issued on Sept. 30, 1969. 

Limits on State Enforcement Procedures 

The Japan Automobile Manufacturers Associa- 
tion has brought to the attention of the NHTSA, in 
a petition for reconsideration of Standard No. 209, 
some leadtime problems that may be caused by the 
safety standard enforcement practices of some of 
the States. These States require manufacturers to 
submit samples of motor vehicle equipment 
covered by one of the standards, such as seat belt 
assemblies, to a State-authorized test laboratory. 
The test reports from the laboratory are then 
submitted to a State agency or an outside agency 
such as the American Association of Motor Vehicle 
Administrators, which issues an "approval" to the 
manufacturer. The problem arises in cases where 
the State does not permit the manufacturer to sell 
the equipment in that State until the approval is 
received. If the leadtime between the issuance of a 



fairly short, the manufacturer may not have time 
to prepare and submit samples and to obtain the 
State-required approval before the effective date 
of the standard. Thus, the manufacturer may be 
prohibited from selling his product in the State on 
and after the effective date, even though it fully 
complies with all applicable Federal standards and 
regulations. 

The substantive relationship between Federal 
and State safety standards was established by 
Congress in section 103(d) of the National Traffic 
and Motor Vehicle Safety Act, which provides: 

"Whenever a Federal motor vehicle safety 
standard established under this title is in effect, 
no State or political subdivision of a State shall 
have any authority either to establish, or to con- 
tinue in effect, with respect to any motor vehicle 
or item of motor vehicle equipment any safety 
standard applicable to the same aspect of 
performance of such vehicle or item of equipment 
which is not identical to the Federal Standard." 

Although this section makes it clear that State 
standards must be "identical" to the Federal 
standards to the extent of the latter's coverage, 
the procedural relationship between State and 
Federal enforcement of the standard is not 
explicitly stated in the Act. It has been the position 
of this agency that the Act permits the States to 
enforce the standards, independently of the 
Federal enforcement effort, since otherwise there 
would have been no reason for the Act to allow the 
States to have even "identical" standards. The 
question raised by the JAMA petition is to what 
extent the States may utilize an enforcement 
scheme that differs from the Federal one established 
by the Act. 

The basic structure of the Act places the burden 
of conformity to the standards on the manufac- 
turers, who must exercise due care to determine 
that all their products comply with applicable 
standards (§§ 103, 108, 15 U.S.C. 1392, 1397). 
They must certify each vehicle and item of covered 
equipment as conforming to the standards (§ 114, 
15 U.S.C. 1403). No prior approval of a manufac- 
turer's products is provided for or contemplated by 
the Act. The NHTSA does not issue such 
approvals, but tests the products after they come 
onto the market to determine whether they con- 
form. Thus, the effective date of a standard is 
established on the basis of the agency's judgment 



PART 571-7 



as to the length of time it will take manufacturers 
to design and prepare to produce a vehicle or item 
of equipment, and is not intended to allow time for 
obtaining governmental approval after production 
begins. 

In this light, a State requirement of obtaining 
prior approval before a product may be sold con- 
flicts with the Federal regulatory scheme. The 
legislative history does not offer specific guidance 
on the question, except for general statements 
such as the following by Senator Magnuson: 

"Some States have more stringent laws than 
others, but concerning the car itself we must 
have uniformity. That is why the bill suggests to 
States that if we set a minimum standard, a car 
complying with such standard should be admitted 
to all States." 112 Cong. Rec. 13585, June 24, 
1966. 

"[W]e have provided in the bill for foreign cars, 
that they must comply with the standards: and 
we have even allowed them to come in under a 
free-port arrangement, where, if they are not in 
compliance, dealers can bring them up to the 
standard." 12 Cong. Rec. 13587, June 24, 1966. 
(Emphasis supplied.) 



It is true that Senator Magnuson in the above 
statements was not directly considering the ques- 
tion of State enforcement. But Congress does not 
appear to have contemplated the existence of State 
procedures that would restrict the free movement 
of vehicles and equipment, or place significant 
burdens on the manufacturers, in areas covered by 
the Federal standards, beyond those imposed by 
the standards themselves. 

It is the position of this agency, therefore, that 
under the Act and the regulatory scheme that has 
been established by its authority a State may not 
regulate motor vehicles or motor vehicle equip- 
ment, with respect to aspects of performance 
covered by Federal standards, by requiring prior 
State approval before sale or otherwise restricting 
the manufacture, sale, or movement within the 
State of products that conform to the standards. 
This interpretation does not preclude State 
enforcement of standards by other reasonable 
procedures that do not impose undue burdens on 
the manufacturers, including submission of pro- 
ducts for approval within reasonable time limits, as 
long as manufacturers are free to market their pro- 
ducts while the procedures are being followed, as 
they are under the Federal scheme. 

Issued on May 13, 1971. 



PART 571-8 



equip them with devices and accessories that 
render them lawful for use and registration for use 
on public highways under state and local laws; (2) 
do not otherwise participate or assist in making 
the vehicles lawful for operation on public roads (as 
by furnishing certificates of origin or other title 
documents, unless those documents contain a 
statement that the vehicles were not manufactured 
for use on public streets, roads, or highways); (3) 
do not advertise or promote them as vehicles 
suitable for use on public roads; (4) do not generally 
market them through retail dealers on motor 
vehicles; and (5) affix to the mini-bikes a notice 
stating in substance that the vehicles were not 
manufactured for use on public streets, roads, or 
highways and warning operators against such use. 
Cases of manufacturers who fulfill some, but not 
all, of the above criteria will be dealt with 
individually under those criteria and such others as 
may be relevant. 

A manufacturer of mini-bikes is, of course, at 
liberty to design and construct his products so that 
they conform to the provisions of the motor vehicle 
safety standards that are applicable to motorcycles 
and thereby to manufacture motor vehicles within 
the meaning of the National Traffic and Motor 
Vehicle Safety Act. 

In consideration of the foregoing, the petitions 
for reconsideration of the February 4, 1969 inter- 
pretation relating to mini-bikes are granted to the 
extent set forth above, and that interpretation is 
withdrawn. 

Issued on Sept. 30, 1969. 

Limits on State Enforcement Procedures 

The Japan Automobile Manufacturers Associa- 
tion has brought to the attention of the NHTSA, in 
a petition for reconsideration of Standard No. 209, 
some leadtime problems that may be caused by the 
safety standard enforcement practices of some of 
the States. These States require manufacturers to 
submit samples of motor vehicle equipment 
covered by one of the standards, such as seat belt 
assemblies, to a State-authorized test laboratory. 
The test reports from the laboratory are then 
submitted to a State agency or an outside agency 
such as the American Association of Motor Vehicle 
Administrators, which issues an "approval" to the 
manufacturer. The problem arises in cases where 
the State does not permit the manufacturer to sell 
the equipment in that State until the approval is 
received. If the leadtime between the issuance of a 



fairly short, the manufacturer may not have time 
to prepare and submit samples and to obtain the 
State-required approval before the effective date 
of the standard. Thus, the manufacturer may be 
prohibited from selling his product in the State on 
and after the effective date, even though it fully 
complies with all applicable Federal standards and 
regulations. 

The substantive relationship between Federal 
and State safety standards was established by 
Congress in section 103(d) of the National Traffic 
and Motor Vehicle Safety Act, which provides: 

"Whenever a Federal motor vehicle safety 
standard established under this title is in effect, 
no State or political subdivision of a State shall 
have any authority either to establish, or to con- 
tinue in effect, with respect to any motor vehicle 
or item of motor vehicle equipment any safety 
standard applicable to the same aspect of 
performance of such vehicle or item of equipment 
which is not identical to the Federal Standard." 

Although this section makes it clear that State 
standards must be "identical" to the Federal 
standards to the extent of the latter's coverage, 
the procedural relationship between State and 
Federal enforcement of the standard is not 
explicitly stated in the Act. It has been the position 
of this agency that the Act permits the States to 
enforce the standards, independently of the 
Federal enforcement effort, since otherwise there 
would have been no reason for the Act to allow the 
States to have even "identical" standards. The 
question raised by the JAMA petition is to what 
extent the States may utilize an enforcement 
scheme that differs from the Federal one established 
by the Act. 

The basic structure of the Act places the burden 
of conformity to the standards on the manufac- 
turers, who must exercise due care to determine 
that all their products comply with applicable 
standards (§§ 103, 108, 15 U.S.C. 1392, 1397). 
They must certify each vehicle and item of covered 
equipment as conforming to the standards (§ 114, 
15 U.S.C. 1403). No prior approval of a manufac- 
turer's products is provided for or contemplated by 
the Act. The NHTSA does not issue such 
approvals, but tests the products after they come 
onto the market to determine whether they con- 
form. Thus, the effective date of a standard is 
established on the basis of the agency's judgment 



PART 571-7 



as to the length of time it will take manufacturers 
to design and prepare to produce a vehicle or item 
of equipment, and is not intended to allow time for 
obtaining governmental approval after production 
begins. 

In this light, a State requirement of obtaining 
prior approval before a product may be sold con- 
flicts with the Federal regulatory scheme. The 
legislative history does not offer specific guidance 
on the question, except for general statements 
such as the following by Senator Magnuson: 

"Some States have more stringent laws than 
others, but concerning the car itself we must 
have uniformity. That is why the bill suggests to 
States that if we set a minimum standard, a car 
complying with such standard should be admitted 
to all States." 112 Cong. Rec. 13585, June 24, 
1966. 

"[W]e have provided in the bill for foreign cars, 
that they must comply with the standards: and 
we have even allowed them to come in under a 
free-port arrangem,ent, where, if they are not in 
compliance, dealers can bring them up to the 
standard." 12 Cong. Rec. 13587, June 24, 1966. 
(Emphasis supplied.) 



It is true that Senator Magnuson in the above 
statements was not directly considering the ques- 
tion of State enforcement. But Congress does not 
appear to have contemplated the existence of State 
procedures that would restrict the free movement 
of vehicles and equipment, or place significant 
burdens on the manufacturers, in areas covered by 
the Federal standards, beyond those imposed by 
the standards themselves. 

It is the position of this agency, therefore, that 
under the Act and the regulatory scheme that has 
been established by its authority a State may not 
regulate motor vehicles or motor vehicle equip- 
ment, with respect to aspects of performance 
covered by Federal standards, by requiring prior 
State approval before sale or otherwise restricting 
the manufacture, sale, or movement within the 
State of products that conform to the standards. 
This interpretation does not preclude State 
enforcement of standards by other reasonable 
procedures that do not impose undue burdens on 
the manufacturers, including submission of pro- 
ducts for approval within reasonable time limits, as 
long as manufacturers are free to market their pro- 
ducts while the procedures are being followed, as 
they are under the Federal scheme. 

Issued on May 13, 1971. 



PART 571-8 



SECTION TWO-PART 571 



standard No. Title 

101 Controls and Displays 

102 Transmission Shift Lever Sequence, Starter 
Interlock and Transmission Braking Effect 

103 Windshield Defrosting and Defogging 
Systems 

104 Windshield Wiping and Washing Systems 

105 Hydraulic Brake Systems 

106 Brake Hoses 

107 Reflecting Surfaces 

108 Lamps, Reflective Devices and Associated 
Equipment 

109 New Pneumatic Tires 

110 Tire Selection and Rims 

111 Rearview Mirrors 

112 Headlamp Concealment Devices 

113 Hood Latch System 

114 Theft Protection 

115 Vehicle Identification Number 

116 Motor Vehicle Brake Fluids 

117 Retreaded Pneumatic Tires 

118 Power-Operated Window Systems 

119 New Pneumatic Tires for Vehicles Other 
Than Passenger Cars 

120 Tire Selection and Rims for Motor Vehicles 
Other Than Passenger Cars 

121 Air Brake Systems 

122 Motorcycle Brake Systems 

123 Motorcycle Controls and Displays 

124 Accelerator Control Systems 



125 Warning Devices 

126 Truck-Camper Loading 

201 Occupant Protection in Interior Impact 

202 Head Restraints 

203 Impact Protection for the Driver From the 
Steering Control System 

204 Steering Control Rearward Displacement 

205 Glazing Materials 

206 Door Locks and Door Retention Compo- 
nents 

207 Seating Systems 

208 Occupant Crash Protection 

209 Seat Belt Assemblies 

210 Seat Belt Assembly Anchorages 

211 Wheel Nuts, Wheel Discs, and Hub Cabs 

212 Windshield Mounting 

213 Child Restraint Systems 

214 Side Door Strength 

215 [Reserved] 

216 Roof Crush Resistance 

217 Bus Window Retention and Release 

218 Motorcycle Helmets 

219 Windshield Zone Intrusion 

220 School Bus Rollover Protection 

221 School Bus Body Joint Strength 

222 School Bus Passenger Seating and Crash 
Protection 

301 Fuel System Integrity 

302 Flammability of Interior Materials 



CFR 49— October 1983 



PART 571-9-10 



f 



SECTION TWO— PART 571 



standard No. Title 

101 Controls and Displays 

102 Transmission Shift Lever Sequence, Starter 
Interlock and Transmission Braking Effect 

103 Windshield Defrosting and Defogging 
Systems 

104 Windshield Wiping and Washing Systems 

105 Hydraulic Brake Systems 

106 Brake Hoses 

107 Reflecting Surfaces 

108 Lamps, Reflective Devices and Associated 
Equipment 

109 New Pneumatic Tires 

110 Tire Selection and Rims 

111 Rearview Mirrors 

112 Headlamp Concealment Devices 

113 Hood Latch System 

114 Theft Protection 

115 Vehicle Identification Number 

116 Motor Vehicle Brake Fluids 

117 Retreaded Pneumatic Tires 

118 Power-Operated Window Systems 

119 New Pneumatic Tires for Vehicles Other 
Than Passenger Cars 

120 Tire Selection and Rims for Motor Vehicles 
Other Than Passenger Cars 

121 Air Brake Systems 

122 Motorcycle Brake Systems 

123 Motorcycle Controls and Displays 

124 Accelerator Control Systems 



125 Warning Devices 

126 Truck-Camper Loading 

201 Occupant Protection in Interior Impact 

202 Head Restraints 

203 Impact Protection for the Driver From the 
Steering Control System 

204 Steering Control Rearward Displacement 

205 Glazing Materials 

206 Door Locks and Door Retention Compo- 
nents 

207 Seating Systems 

208 Occupant Crash Protection 

209 Seat Belt Assemblies 

210 Seat Belt Assembly Anchorages 

211 Wheel Nuts, Wheel Discs, and Hub Cabs 

212 Windshield Mounting 

213 Child Restraint Systems 

214 Side Door Strength 

215 [Reserved] 

216 Roof Crush Resistance 

217 Bus Window Retention and Release 

218 Motorcycle Helmets 

219 Windshield Zone Intrusion 

220 School Bus Rollover Protection 

221 School Bus Body Joint Strength 

222 School Bus Passenger Seating and Crash 
Protection 

301 Fuel System Integrity 

302 Flammability of Interior Materials 



CFR 49-October 1983 



PART 571-9-10 



^f 



r 



Section Two 
Alphabetical Listing 

Tni9 standard No. 

Accelerator Control Systems 124 

Brake Fluids 116 

Brake Hoses 106 

Brakes, Air Systems 121 

Brakes, Hydraulic 105 

Brakes, Motorcycles 122 

Bus Window Retention and Release 217 

Child Restraint Systems 213 

Controls and Displays, Motorcycle 123 

Controls and Displays 101 

Door Locks and Door Retention Components 206 

Flammability of Interior Materials 302 

Fuel System Integrity 301 

Glazing Materials 205 

Headlamp Concealment Devices 112 

Head Restraints 202 

Hood Latch Systems 113 

Impact Protection for the Driver from the Steering Control System 203 

Lamps, Reflective Devices and Associated Equipment 108 

Mirrors, Rearview Ill 

Motorcycle Helmets 218 

Occupant Crash Protection 208 

Occupant Protection in Interior Impact 201 

Reflecting Surfaces 107 

Roof Crush Resistance 216 

School Bus Body Joint Strength 221 

School Bus Rollover Protection 220 

School Bus Seating and Crash Protection 222 

Seat Belt Assemblies 209 

Seat Belt Assembly Anchorages 210 

Seating Systems 207 

Side Door Strength 214 

Steering Control Rearward Displacement 204 

Theft Protection 114 

(Continued—) 

PART f;71_11 



Alphabetical Listing— Con f/nued 

Title Standard No. 

Tires, New Pneumatic 109 

Tires, New Pneumatic for Vehicles Other Than Passenger Cars 119 

Tires, Retreaded Pneumatic 117 

Tire Selection and Rims 110 

Tire Selection and Rims, for Vehicles Other Than for Passenger Cars 120 

Transmission Shift Lever Sequence, Starter Interlock and Transmission 

Braking Effect 102 

Truck . Camper Loading 126 

Vehicle Identification Number 115 

Warning Devices 125 

Wheel Nuts, Wheel Discs and Hub Caps 211 

Window Systems, Power-Operated 118 

Windshield Defrosting and Defogging Systems 103 

Windshield Mounting 212 

Windshield Wiping and Washing Systems 104 

Windshield Zone Intrusion 219 



PART 571-12 



Section Two 
Alphabetical Listing 

Title standard No. 

Accelerator Control Systems 124 

Brake Fluids 116 

Brake Hoses 106 

Brakes, Air Systems 121 

Brakes, Hydraulic 105 

Brakes, Motorcycles 122 

Bus Window Retention and Release 217 

Child Restraint Systems 213 

Controls and Displays, Motorcycle 123 

Controls and Displays 101 

Door Locks and Door Retention Components 206 

Flammability of Interior Materials 302 

Fuel System Integrity 301 

Glazing Materials 205 

Headlamp Concealment Devices 112 

Head Restraints 202 

Hood Latch Systems 113 

Impact Protection for the Driver from the Steering Control System 203 

Lamps, Reflective Devices and Associated Equipment 108 

Mirrors, Rearview Ill 

Motorcycle Helmets 218 

Occupant Crash Protection 208 

Occupant Protection in Interior Impact 201 

Reflecting Surfaces 107 

Roof Crush Resistance 216 

School Bus Body Joint Strength 221 

School Bus Rollover Protection 220 

School Bus Seating and Crash Protection 222 

Seat Belt Assemblies 209 

Seat Belt Assembly Anchorages 210 

Seating Systems 207 

Side Door Strength 214 

Steering Control Rearward Displacement 204 

Theft Protection 114 

(Continued—) 

PART 1^71-11 



Alphabetical UsWng— Continued 

Title Standard No. 

Tires, New Pneumatic 109 

Tires, New Pneumatic for Vehicles Other Than Passenger Cars 119 

Tires, Retreaded Pneumatic 117 

Tire Selection and Rims 110 

Tire Selection and Rims, for Vehicles Other Than for Passenger Cars 120 

Transmission Shift Lever Sequence, Starter Interlock and Transmission 

Braking Effect 102 

Truck . Camper Loading 126 

Vehicle Identification Number 115 

Warning Devices 125 

Wheel Nuts, Wheel Discs and Hub Caps 211 

Window Systems, Power-Operated 118 

Windshield Defrosting and Defogging Systems 103 

Windshield Mounting 212 

Windshield Wiping and Washing Systems 104 

Windshield Zone Intrusion 219 



PART 571-12 



PREAMBLE TO AN AMENDMENT TO 
FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 



101 



Federal Motor Vehicle Safety Standards; 

Controls and Displays 

[Docket No. 1-18, Notice 25; No. 70-27, Notice 29] 



ACTION: Final rule. 

SUMMARY: Standard No. 101, Controls and 
Displays, specifies requirements for the ac- 
cessibility, identification and illumination of con- 
trols and displays in passenger cars, trucks, and 
buses. This notice amends several of the identifi- 
cation requirements of the standard to improve 
safety by providing easily recognizable, interna- 
tional symbols and to relieve unnecessary restric- 
tions on manufacturers by providing additional 
flexibility in their ability to identify controls and 
displays. This notice also responds to manufac- 
turer petitions. The amendments include replace- 
ing the symbol specified for headlamp/tail lamp 
controls that are part of master lighting switches 
with the International Standards Organization 
(ISO) master lighting switch symbol, while making 
the identification for headlamp/taU lamp controls 
that are separate from master lighting switches at 
the option of the manufacturer; making a minor 
modification in the symbol specified for the 
clearance lamp system control; permitting several 
symbols to be used in solid or outline form; specify- 
ing that horn controls, with limited exceptions, be 
identified by the ISO horn symbol; permitting 
several heating and air conditioning controls to be 
identified by symbols as an alternative to words, 
with the choice of the particular symbols left to the 
discretion of the manufacturer; and making minor 
interpretive amendments. This notice also makes 
minor interpretive amendments in related iden- 
tification requirements of Standard No. 105, 
Hydraulic Brake Systems. 

EFFECTIVE DATE: The amendments are effective 
on July 27, 1984. Some amendments are of an 



optional nature. Others are optional now and 
become mandatory on September 1, 1987. 

SUPPLEMENTARY INFORMATION: Standard 
No. 101, Controls and Displays, speciiies require- 
ments for the accessibility, identification and Ulu- 
mination of controls and displays in passenger cars, 
multipurpose passenger vehicles, trucks and buses. 
The purpose of the standard is to ensure the acces- 
sibility and visibility of motor vehicle controls and 
displays to a driver and to facilitate their quick 
and proper identification and selection by a driver 
in order to reduce the safety hazards caused by the 
diversion of the driver's attention from the driving 
task, and by mistakes in selecting controls. 

On November 4, 1982, NHTSA published (47 FR 
49993) a notice of proposed rulemaking (NPRM) to 
update Standard No. 101 by adding or modifying 
several symbols to bring the standard into har- 
mony with recent documents promulgated by the 
International Standards Organization (ISO). The 
agency also proposed minor interpretive amend- 
ments. The November 1982 notice was issued in 
light of changing international standards specify- 
ing symbols for the identification of controls and 
displays. These standards include, in addition to 
the ISO standard, those of the United Nations 
Economic Commission for Europe (ECE) and the 
European Economic Community (EEC). The pro- 
posal resulted in part from a petition for rule- 
making submitted by Renault. 

NHTSA received numerous comments on the 
proposal, mostly from manufacturers. Since issu- 
ing the NPRM, the agency has received several 
other petitions for rulemaking from manufacturers 
concerning Standard No. 101, some of which 
followed directly from the proposal. During the 



PART 571; SlOl- PRE 11 



same time period, the agency has also been in the 
process of considering comments and related peti- 
tions concerning a separate earlier NPRM to 
amend other aspects (other than specific symbol 
identification) of Standard No. 101. That proposal 
was published in the Federal Register (47 FR 4541) 
on February 1, 1982. 

The various comments and petitions relating to 
one or the other proposal raise a number of issues, 
many of which are closely interrelated. After 
reviewing all of the comments and petitions, 
NHTSA has decided to adopt certain limited 
amendments at this time from the November 1982 
NPRM. This action will enable manufacturers to 
appropriately, and in a timely fashion, identify 
their controls and displays while maintaining and 
improving safety by adopting internationally ac- 
cepted symbols for identifying these devices. The 
agency is postponing a final decision on the rest of 
the amendments proposed by the two notices 
pending completion of an ongoing examination by 
the agency of issues related to Standard No. 101. 
This examination is expected to be complete this 
summer. Although this examination will broadly 
cover the requirements of Standard No. 101, it is 
anticipated to result in a Notice of Proposed 
Rulemaking, final action on which will not be 
timely to respond to the immediate needs of the 
manufacturers and the public. Thus, issuance of 
this final rule is necessary at this time. 

The amendments adopted at this time include: 
(1) replacing the symbol specified for headlamp/tail 
lamp controls that are part of master lighting swit- 
ches with the ISO master lighting switch symbol, 
while making the required identification for head- 
lamp/tail lamp controls that are separate from 
master lighting switches at the option of the 
manufacturer, (2) making a minor modification in 
the symbol specified for the clearance lamp system 
control, (3) permitting several symbols to be used 
in solid or outline form, (4) specifying that horn 
controls, with limited exceptions, be identified by 
the ISO horn symbol, (5) permitting heating and air 
conditioning controls to be identified by symbols 
as an alternative to words, with the symbols at the 
option of the manufacturer, and (6) making minor 
interpretive amendments. 

As discussed below, the effective date for certain 
new or changed symbols is September 1, 1987. An 
immediate effective date is established for optional 
use of the new or changed symbols and for the other 
amendments, all of which are of an optional nature. 



The discussion of issues and comments which 
follows is largely limited to those relating to the 
amendments adopted by this notice. Remaining 
issues will be addressed after the agency has com- 
pleted its comprehensive examination of issues 
related to Standard No. 101. 

Symbol Requirements 

The November 1982 notice explained that Stan- 
dard No. 101 specifies the mandatory use of cer- 
tain symbols for the identification of a number of 
controls and displays. Additional words and sym- 
bols are permitted to be used for purposes of in- 
creasing clarity of the identification. (Standard No. 
101 requires several other controls and displays, 
for which symbols are not specified, to be identi- 
fied by words. Also, the use of words instead of 
symbols is permitted in informational readout dis- 
plays.) The symbols specified by the standard are 
those developed by the International Standards 
Organization or similar symbols based on ISO stan- 
dards. In the notice adopting the use of these sym- 
bols (43 FR 27541, June 26, 1978), the agency ex- 
plained that the rationale for requiring symbols 
was that they can convey information more quick- 
ly and with less chance of human error than words. 
The agency noted that this was particularly true 
with respect to the large foreign language speak- 
ing population of this country. The agency also in- 
dicated that an additional benefit was that manu- 
facturers which sell vehicles both in and outside of 
the United States could realize cost savings by 
utilizing internationally acceptable symbols. 

As noted above, the November 1982 notice pro- 
posed to update Standard No. 101 by adding or 
modifying several symbols to bring the standard 
into harmony with the latest documents pro- 
mulgated by the ISO. The agency stated that the 
changes would reduce compliance costs by pro- 
moting international harmonization and would 
result in safety benefits. 

Almost all of the comments supported the con- 
cept of changing Standard No. 101 to facilitate in- 
ternational harmonization. The comments were 
mixed, however, with respect to some of the specific 
proposed amendments, especially to the extent that 
the number of required symbols would be increased. 

While some manufacturers strongly supported 
the amendments essentially as proposed, others 
questioned the underlying safety need for the 
standard's requirement for symbols. Concern was 
expressed by some manufacturers that an increased 



PART 571; SlOl -PRE 12 



PREAMBLE TO AN AMENDMENT TO 
FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 



101 



Federal Motor Vehicle Safety Standards; 

Controls and Displays 

[Docket No. M8, Notice 25; No. 70-27, Notice 29] 



ACTION: Final rule. 

SUMMARY: Standard No. 101, Controls and 
Displays, specifies requirements for the ac- 
cessibility, identification and illumination of con- 
trols and displays in passenger cars, trucks, and 
buses. This notice amends several of the identifi- 
cation requirements of the standard to improve 
safety by providing easily recognizable, interna- 
tional symbols and to relieve unnecessary restric- 
tions on manufacturers by providing additional 
flexibility in their ability to identify controls and 
displays. This notice also responds to manufac- 
turer petitions. The amendments include replace- 
ing the symbol specified for headlamp/taU lamp 
controls that are part of master lighting switches 
with the International Standards Organization 
(ISO) master lighting switch symbol, while making 
the identification for headlamp/tail lamp controls 
that are separate from master lighting switches at 
the option of the manufacturer; making a minor 
modification in the symbol specified for the 
clearance lamp system control; permitting several 
symbols to be used in solid or outline form; specify- 
ing that horn controls, with limited exceptions, be 
identified by the ISO horn symbol; permitting 
several heating and air conditioning controls to be 
identified by symbols as an alternative to words, 
with the choice of the particular symbols left to the 
discretion of the manufacturer; and making minor 
interpretive amendments. This notice also makes 
minor interpretive amendments in related iden- 
tification requirements of Standard No. 105, 
Hydraulic Brake Systems. 

EFFECTIVE DATE: The amendments are effective 
on July 27, 1984. Some amendments are of an 



optional nature. Others are optional now and 
become mandatory on September 1, 1987. 

SUPPLEMENTARY INFORMATION: Standard 
No. 101, Controls and Displays, specifies require- 
ments for the accessibility, identification and illu- 
mination of controls and displays in passenger cars, 
multipurpose passenger vehicles, trucks and buses. 
The purpose of the standard is to ensure the acces- 
sibility and visibility of motor vehicle controls and 
displays to a driver and to facilitate their quick 
and proper identification and selection by a driver 
in order to reduce the safety hazards caused by the 
diversion of the driver's attention from the driving 
task, and by mistakes in selecting controls. 

On November 4, 1982, NHTSA published (47 FR 
49993) a notice of proposed rulemaking (NPRM) to 
update Standard No. 101 by adding or modifying 
several symbols to bring the standard into har- 
mony with recent documents promulgated by the 
International Standards Organization (ISO). The 
agency also proposed minor interpretive amend- 
ments. The November 1982 notice was issued in 
light of changing international standards specify- 
ing symbols for the identification of controls and 
displays. These standards include, in addition to 
the ISO standard, those of the United Nations 
Economic Commission for Europe (ECE) and the 
European Economic Community (EEC). The pro- 
posal resulted in part from a petition for rule- 
making submitted by Renault. 

NHTSA received numerous comments on the 
proposal, mostly from manufacturers. Since issu- 
ing the NPRM, the agency has received several 
other petitions for rulemaking from manufacturers 
concerning Standard No. 101, some of which 
followed directly from the proposal. During the 



I 



PART 571; S 101 -PRE 11 



same time period, the agency has also been in the 
process of considering comments and related peti- 
tions concerning a separate earlier NPRM to 
amend other aspects (other than specific symbol 
identification) of Standard No. 101. That proposal 
was published in the Federal Register (47 FR 4541) 
on February 1, 1982. 

The various comments and petitions relating to 
one or the other proposal raise a number of issues, 
many of which are closely interrelated. After 
reviewing all of the comments and petitions, 
NHTSA has decided to adopt certain limited 
amendments at this time from the November 1982 
NPRM. This action will enable manufacturers to 
appropriately, and in a timely fashion, identify 
their controls and displays while maintaining and 
improving safety by adopting internationally ac- 
cepted symbols for identifying these devices. The 
agency is postponing a final decision on the rest of 
the amendments proposed by the two notices 
pending completion of an ongoing examination by 
the agency of issues related to Standard No. 101. 
This examination is expected to be complete this 
summer. Although this examination will broadly 
cover the requirements of Standard No. 101, it is 
anticipated to result in a Notice of Proposed 
Rulemaking, final action on which will not be 
timely to respond to the immediate needs of the 
manufacturers and the public. Thus, issuance of 
this final rule is necessary at this time. 

The amendments adopted at this time include: 
(1) replacing the symbol specified for headlamp/tail 
lamp controls that are part of master lighting swit- 
ches with the ISO master lighting switch symbol, 
while making the required identification for head- 
lamp/tail lamp controls that are separate from 
master lighting switches at the option of the 
manufacturer, (2) making a minor modification in 
the symbol specified for the clearance lamp system 
control, (3) permitting several symbols to be used 
in solid or outline form, (4) specifying that horn 
controls, with limited exceptions, be identified by 
the ISO horn symbol, (5) permitting heating and air 
conditioning controls to be identified by symbols 
as an alternative to words, with the symbols at the 
option of the manufacturer, and (6) making minor 
interpretive amendments. 

As discussed below, the effective date for certain 
new or changed symbols is September 1, 1987. An 
immediate effective date is established for optional 
use of the new or changed symbols and for the other 
amendments, all of which are of an optional nature. 



The discussion of issues and comments which 
follows is largely limited to those relating to the 
amendments adopted by this notice. Remaining 
issues will be addressed after the agency has com- 
pleted its comprehensive examination of issues 
related to Standard No. 101. 

Symbol Requirements 

The November 1982 notice explained that Stan- 
dard No. 101 specifies the mandatory use of cer- 
tain symbols for the identification of a number of 
controls and displays. Additional words and sym- 
bols are permitted to be used for purposes of in- 
creasing clarity of the identification. (Standard No. 
101 requires several other controls and displays, 
for which symbols are not specified, to be identi- 
fied by words. Also, the use of words instead of 
symbols is permitted in informational readout dis- 
plays.) The symbols specified by the standard are 
those developed by the International Standards 
Organization or similar symbols based on ISO stan- 
dards. In the notice adopting the use of these sym- 
bols (43 FR 27541, June 26, 1978), the agency ex- 
plained that the rationale for requiring symbols 
was that they can convey information more quick- 
ly and with less chance of human error than words. 
The agency noted that this was particularly true 
with respect to the large foreign language speak- 
ing population of this country. The agency also in- 
dicated that an additional benefit was that manu- 
facturers which sell vehicles both in and outside of 
the United States could realize cost savings by 
utilizing internationally acceptable symbols. 

As noted above, the November 1982 notice pro- 
posed to update Standard No. 101 by adding or 
modifying several symbols to bring the standard 
into harmony with the latest documents pro- 
mulgated by the ISO. The agency stated that the 
changes would reduce compliance costs by pro- 
moting international harmonization and would 
result in safety benefits. 

Almost all of the comments supported the con- 
cept of changing Standard No. 101 to facilitate in- 
ternational harmonization. The comments were 
mixed, however, with respect to some of the specific 
proposed amendments, especially to the extent that 
the number of required symbols would be increased. 

While some manufacturers strongly supported 
the amendments essentially as proposed, others 
questioned the underlying safety need for the 
standard's requirement for symbols. Concern was 
expressed by some manufacturers that an increased 



PART 571; SlOl-PRE 12 



number of required symbols could result in 
greater risk of producing non-conforming vehicles, 
with the possibility of having to recall vehicles. 

General Motors expressed concern that either 
requiring an overabundance of symbols, or re- 
quiring symbols that offer no intuitive recogniz- 
ability, would not be in the best interests of its 
customers or the marketability of its products. 
That company stated that while the existing set of 
required symbols does not present a significant 
problem, the addition of more mandatory symbols 
could lead to increased customer resistance and 
driver confusion. On this last point, General 
Motors stated that the symbols most recently 
adopted by the ISO have been adopted without 
testing to assure immediate recognizability, with a 
gfreater probability that the meaning of the sym- 
bols must be learned. 

The agency agrees that too many symbols, or 
s3rmbols that are not easily recognizable, are not in 
the public's or industry's interest. For this reason, 
the agency has postponed action on some of the ad- 
ditional requirements proposed in the November 
1982 notice. These will be addressed in the 
agency's forthcoming evaluating of Standard No. 
101. Thus, this final rule adds one completely new 
symbol (the horn symbol) to the standard and 
changes or modifies several others. The agency 
believes, based on the comments to the docket and 
the work of the ISO, that each of the new and 
modified symbols is easily recognizable. The 
agency also believes that the amendments will not 
create confusion or any other problems related to 
a possible "overabundance" of symbols, because of 
their limited nature. The agency will consider the 
broader issues of possible "overabundance" of 
symbols and of new sjrmbols which may not offer 
intuitive recognizability as part of its comprehen- 
sive examination of Standard No. 101 issues. 

Master Lighting Switch Symbol 
As explained in the November 1982 notice, the 
proposal to replace the symbol specified for the 
headlamp/tail lamp control with the master 
lighting symbol resulted in part from a petition for 
rulemaking submitted by Renault. Renault's peti- 
tion had pointed out that the symbol specified by 
Standard No. 101 for that control is different from 
that used elsewhere in the world. That petitioner 
noted that the Standard No. 101 symbol is that 
designated by the ISO for high beam headlamps, 
rather than for the headlamp/tail lamp control. 



Most of the commenters supported changing to 
the master lighting symbol. General Motors stated 
that it supports the proposal to revise the symbols 
for those control and display functions which al- 
ready require identification in order to bring them 
into harmonization with European requirements, 
including replacing the headlamp symbol with the 
master lighting symbol. Several other manufac- 
turer comments specifically supported the change. 

Renault stated that while it approves without 
reservation the introduction of the master lighting 
symbol into the standard, the list of functions cor- 
responding to the symbol g^ven in column 1 of 
Table 1 should be expanded or at best omitted 
altogether. The proposed wording in column 1 
referred to by Renault was "Master Lighting 
Switch, Headlamp and Tail Lamps." 

One commenter, Grumman Flxible, disagreed 
with changing to the master lighting symbol. That 
company argued that the symbol is too ambiguous, 
does not specifically indicate that the lamps it 
represents include headlamps, and also represents 
additional components not specifically indicated. 
Grumman Flxible also argued that the symbol is 
not immediately recognizable, due to both an ini- 
tial unfamiliarity with the symbol in this country 
and because the pictogram is too abstract in 
nature. That commenter also stated that the sym- 
bol does not allow for any distinction between the 
headlamp mode and parking light mode, and that 
that issue should be addressed. Finally, Grunmian 
Flxible stated that it finds no evidence that the 
symbol is used by the rest of the world for head- 
lamps and that most foreign vehicles it is familiar 
with use the current Standard No. 101 headlamp 
symbol. 

Fiat stated that identification for the headlamp 
control has been omitted from Table 1. According 
to that commenter, the headlamp symbol should be 
required for the identification of the high beam/low 
beam switch if this is separate from the master 
lighting switch. 

This notice adopts the master lighting switch 
symbol for headlamp/tail lamp controls that are 
also master lighting switches, Le., single controls 
that operate several different lamp systems. The 
agency continues to require identification of head- 
lamp/tail lamp controls that are separate from the 
master lighting switch. However, the agency has 
decided that the method of identifying headlamp/ 
tail lamp controls should be at the option of the 
manufacturer. 



PART 571; SlOl-PRE 13 



Standard No. 101 currently specifies the same 
symbol for headlamp/tail lamp controls whether or 
not such controls are also master lighting switches. 
The description of the control designated in col- 
umn 1 of Table 1 is "Headlamps and Tail Lamps." 
A footnote indicates that the symbol must also be 
used when clearance, identification, parking and/or 
side marker lamps are controlled with the head- 
lamp switch. The type of control described by the 
footnote is a master lighting switch. Typical pas- 
senger cars, as well as many other vehicles, have 
master lighting switches instead of separate con- 
trols for various types of lamps. 

The November 1982 notice proposed the use of 
the master lighting switch symbol for both master 
lighting switches and separate headlamp/tail lamp 
controls. The proposed description for column 1 of 
Table 1 referred to by Renault, "Master Lighting 
Switch, Headlamp and Tail Lamps", indicated that 
the symbol was to apply to both types of controls. 
Thus, the words "Headlamp and Tail Lamps" were 
not intended to be a list of functions corresponding 
to the master lighting switch. 

The agency believes that the master lighting 
switch symbol is the most appropriate and easily 
recognizable symbol to identify master lighting 
switches. The agency does not agree with Grum- 
man Flxible that the symbol is not immediately 
recognizable or that the pictogram is too abstract. 
The symbol in question obviously resembles a light 
bulb with lines representing rays of light going out 
in all directions. Since the control operates several 
different lamps, typically including at least head- 
lamps and tail lamps, parking lamps and side 
marker lamps, the agency considers such a general 
lighting symbol to be more appropriate than one 
which more specifically indicates a single par- 
ticular type of lamp, i.e., headlamps. With regard 
to Grumman Flxible's statement that the symbol 
does not allow for any distinction between the 
headlamp mode and parking mode, the agency 
notes that Standard No. 101 permits the use of 
words or symbols in addition to those required, for 
purposes of clarity. Thus, a manufacturer may, but 
is not required to, use such words or symbols to 
distinguish between different modes. 

The agency does not understand Grumman Flxi- 
ble's statement that it finds no evidence that the 
symbol is used by the rest of the world for head- 
lamps and that most foreign vehicles it is familiar 
with use the current Standard No. 101 headlamp 
symbol. The master lighting switch symbol is 



specified by both the ISO and European Economic 
Community and is required for vehicles produced 
for sale in the European market. 

The agency has decided that it would not be ap- 
propriate to require the master lighting switch 
symbol to be used for headlamp/tail lamp controls 
that are separate from a master lighting switch. 
The general master lighting switch symbol could 
be confusing in such instances. For example, a 
driver might see the master lighting switch sym- 
bol and believe that it operated all of the vehicle's 
lamps instead of only the headlamps. Also, iden- 
tification which more specifically indicates head- 
lamps, such as the symbols specified by the ISO, 
might be more appropriate. The agency has de- 
cided that identification should continue to be re- 
quired for a separate headlamp/tail lamp control 
and has therefore included that control in Table 1. 
The agency has decided, however, that the specific 
identification for such a control should be at the op- 
tion of the manufacturer. 

Clearance Lamp Symbol 

The November 1982 notice proposed a minor 
modification in the symbol specified for the 
clearance lamp system control. The notice also pro- 
posed a change in the applicability of the symbol to 
identification lamp and side marker lamp controls. 

The notice explained that there are three very 
similar versions of this symbol. The reason for the 
multiple versions appears to be that the symbol 
was still under consideration by the ISO when the 
United States and Europe established their iden- 
tification requirements, and it was not clear which 
specific symbol would be adopted. The agency pro- 
posed in November 1982 deleting the version cur- 
rently included in Standard No. 101 and adopting 
the version finally specified by the ISO in the in- 
terests of cost minimization through harmoniza- 
tion. That is the same version specified by the 
European Economic Community (EEC). The third 
version is specified by the United Nations 
Economic Commission for Europe (ECE). The 
agency explained that, as essentially the same 
symbol, all three versions are equally effective at 
presenting their message. The agency added, how- 
ever, that for purposes of optimal driver recogni- 
tion and cost minimization through international 
harmonization, it believed that it was desirable to 
specify the use of only one of the three versions. 

Several manufacturer commenters agreed that 
the ISO/EEC version should be specified by 



PART 571; SlOl -PRE 14 



number of required symbols could result in 
greater risk of producing non-conforming vehicles, 
with the possibility of having to recall vehicles. 

General Motors expressed concern that either 
requiring an overabundance of symbols, or re- 
quiring symbols that offer no intuitive recogniz- 
ability, would not be in the best interests of its 
customers or the marketabUity of its products. 
That company stated that while the existing set of 
required symbols does not present a significant 
problem, the addition of more mandatory symbols 
could lead to increased customer resistance and 
driver confusion. On this last point. General 
Motors stated that the symbols most recently 
adopted by the ISO have been adopted without 
testing to assure immediate recognizability, with a 
greater probability that the meaning of the sym- 
bols must be learned. 

The agency agrees that too many symbols, or 
symbols that are not easily recognizable, are not in 
the public's or industry's interest. For this reason, 
the agency has postponed action on some of the ad- 
ditional requirements proposed in the November 
1982 notice. These will be addressed in the 
agency's forthcoming evaluating of Standard No. 
101. Thus, this final rule adds one completely new 
symbol (the horn symbol) to the standard and 
changes or modifies several others. The agency 
believes, based on the comments to the docket and 
the work of the ISO, that each of the new and 
modified symbols is easily recognizable. The 
agency also believes that the amendments will not 
create confusion or any other problems related to 
a possible "overabundance" of symbols, because of 
their limited nature. The agency will consider the 
broader issues of possible "overabundance" of 
symbols and of new symbols which may not offer 
intuitive recognizability as part of its comprehen- 
sive examination of Standard No. 101 issues. 

Master Lighting Switch Symbol 

As explained in the November 1982 notice, the 
proposal to replace the symbol specified for the 
headlamp/tail lamp control with the master 
lighting symbol resulted in part from a petition for 
rulemaking submitted by Renault. Renault's peti- 
tion had pointed out that the symbol specified by 
Standard No. 101 for that control is different from 
that used elsewhere in the world. That petitioner 
noted that the Standard No. 101 symbol is that 
designated by the ISO for high beam headlamps, 
rather than for the headlamp/tail lamp control. 



Most of the commenters supported changing to 
the master lighting symbol. General Motors stated 
that it supports the proposal to revise the symbols 
for those control and display functions which al- 
ready require identification in order to bring them 
into harmonization with European requirements, 
including replacing the headlamp symbol with the 
master lighting symbol. Several other manufac- 
turer comments specifically supported the change. 

Renault stated that while it approves without 
reservation the introduction of the master lighting 
symbol into the standard, the list of functions cor- 
responding to the symbol given in column 1 of 
Table 1 should be expanded or at best omitted 
altogether. The proposed wording in column 1 
referred to by Renault was "Master Lighting 
Switch, Headlamp and Tail Lamps." 

One commenter, Grumman Flxible, disagreed 
with changing to the master lighting symbol. That 
company argued that the symbol is too ambiguous, 
does not specifically indicate that the lamps it 
represents include headlamps, and also represents 
additional components not specificaUy indicated. 
Grumman Flxible also argued that the symbol is 
not immediately recognizable, due to both an ini- 
tial unfamiliarity with the symbol in this country 
and because the pictogram is too abstract in 
nature. That commenter also stated that the sym- 
bol does not allow for any distinction between the 
headlamp mode and parking light mode, and that 
that issue should be addressed. Finally, Grumman 
Flxible stated that it finds no evidence that the 
symbol is used by the rest of the world for head- 
lamps and that most foreign vehicles it is familiar 
with use the current Standard No. 101 headlamp 
symbol. 

Fiat stated that identification for the headlamp 
control has been omitted from Table 1. According 
to that commenter, the headlamp symbol should be 
required for the identification of the high beamAow 
beam switch if this is separate from the master 
lighting switch. 

This notice adopts the master lighting switch 
symbol for headlamp/tail lamp controls that are 
also master lighting switches, i.e., single controls 
that operate several different lamp systems. The 
agency continues to require identification of head- 
lamp/tail lamp controls that are separate from the 
master lighting switch. However, the agency has 
decided that the method of identifying headlamp/ 
tail lamp controls should be at the option of the 
manufacturer. 



PART 571; SlOl-PRE 13 



standard No. 101 currently specifies the same 
symbol for headlamp/tail lamp controls whether or 
not such controls are also master lighting switches. 
The description of the control designated in col- 
umn 1 of Table 1 is "Headlamps and Tail Lamps." 
A footnote indicates that the symbol must also be 
used when clearance, identification, parking and/or 
side marker lamps are controlled with the head- 
lamp switch. The type of control described by the 
footnote is a master lighting switch. Typical pas- 
senger cars, as well as many other vehicles, have 
master lighting switches instead of separate con- 
trols for various types of lamps. 

The November 1982 notice proposed the use of 
the master lighting switch symbol for both master 
lighting switches and separate headlamp/tail lamp 
controls. The proposed description for column 1 of 
Table 1 referred to by Renault, "Master Lighting 
Switch, Headlamp and Tail Lamps", indicated that 
the symbol was to apply to both types of controls. 
Thus, the words "Headlamp and TaU Lamps" were 
not intended to be a list of functions corresponding 
to the master lighting switch. 

The agency believes that the master lighting 
switch symbol is the most appropriate and easily 
recognizable symbol to identify master lighting 
switches. The agency does not agree with Grum- 
man Flxible that the symbol is not immediately 
recognizable or that the pictogram is too abstract. 
The symbol in question obviously resembles a light 
bulb with lines representing rays of light going out 
in all directions. Since the control operates several 
different lamps, typically including at least head- 
lamps and tail lamps, parking lamps and side 
marker lamps, the agency considers such a general 
lighting symbol to be more appropriate than one 
which more specifically indicates a single par- 
ticular type of lamp, i.e., headlamps. With regard 
to Grumman Flxible's statement that the symbol 
does not allow for any distinction between the 
headlamp mode and parking mode, the agency 
notes that Standard No. 101 permits the use of 
words or symbols in addition to those required, for 
purposes of clarity. Thus, a manufacturer may, but 
is not required to, use such words or symbols to 
distinguish between different modes. 

The agency does not understand Grumman Flxi- 
ble's statement that it finds no evidence that the 
symbol is used by the rest of the world for head- 
lamps and that most foreign vehicles it is familiar 
with use the current Standard No. 101 headlamp 
symbol. The master lighting switch symbol is 



specified by both the ISO and European Economic 
Community and is required for vehicles produced 
for sale in the European market. 

The agency has decided that it would not be ap- 
propriate to require the master lighting switch 
symbol to be used for headlamp/tail lamp controls 
that are separate from a master lighting switch. 
The general master lighting switch symbol could 
be confusing in such instances. For example, a 
driver might see the master lighting switch sym- 
bol and believe that it operated all of the vehicle's 
lamps instead of only the headlamps. Also, iden- 
tification which more specifically indicates head- 
lamps, such as the symbols specified by the ISO, 
might be more appropriate. The agency has de- 
cided that identification should continue to be re- 
quired for a separate headlamp/tail lamp control 
and has therefore included that control in Table 1. 
The agency has decided, however, that the specific 
identification for such a control should be at the op- 
tion of the manufacturer. 

Clearance Lamp Symbol 

The November 1982 notice proposed a minor 
modification in the symbol specified for the 
clearance lamp system control. The notice also pro- 
posed a change in the applicability of the symbol to 
identification lamp and side marker lamp controls. 

The notice explained that there are three very 
similar versions of this symbol. The reason for the 
multiple versions appears to be that the symbol 
was still under consideration by the ISO when the 
United States and Europe established their iden- 
tification requirements, and it was not clear which 
specific symbol would be adopted. The agency pro- 
posed in November 1982 deleting the version cur- 
rently included in Standard No. 101 and adopting 
the version finally specified by the ISO in the in- 
terests of cost minimization through harmoniza- 
tion. That is the same version specified by the 
European Economic Community (EEC). The third 
version is specified by the United Nations 
Economic Commission for Europe (ECE). The 
agency explained that, as essentially the same 
symbol, all three versions are equally effective at 
presenting their message. The agency added, how- 
ever, that for purposes of optimal driver recogni- 
tion and cost minimization through international 
harmonization, it believed that it was desirable to 
specify the use of only one of the three versions. 

Several manufacturer commenters agreed that 
the ISO/EEC version should be specified by 



PART 571; SlOl- PRE 14 



Standard No. 101. Some commenters stated that 
the ECE version should not be permitted as an al- 
ternative, since it would be contrary to the antici- 
pated goal of harmonization. It was also pointed 
out that the ECE version is in a draft regulation 
and may not be finally adopted by that organization. 

GM agreed that it is desirable to have one sym- 
bol ultimately prevaU and suggested that NHTSA 
work within the ECE to resolve differences. GM 
argued, however, that resolving the differences is 
a harmonization issue rather than a safety issue 
and suggested that all three versions be permitted 
in the meantime. GM commented that all three 
versions are reasonably recognizable and similar 
enough in form that confusion should not result. 
Volkswagen similarly commented that the ver- 
sions are virtually identical. 

While it is true that the three versions are 
similar, the agency believes that for purposes of 
easy recognition only one should be specified. The 
leadtime provided by this notice gives adequate 
time for manufacturers to make the very minor 
changes necessitated by adoption of the ISO ver- 
sion, as proposed. 

Grumman Flxible suggested that the ECE sym- 
bol for parking lights be adopted in place of the 
clearance lamp symbol. (The ECE symbol is the 
same as the ISO symbol.) That commenter ap- 
peared to believe that the clearance lamp symbol 
must be used for the master lighting switch when 
it is adjusted so that all lights except the 
headlamps are on, or for a separate parking light 
control. The clearance lamp symbol need not be 
used in either instance. The clearance lamp symbol 
is only specified for a separate control for iden- 
tification, side marker and/or clearance lamps. As 
indicated above, manufacturers may, but need not, 
supplement the master lighting switch symbol 
with additional symbols to identify the lights 
operated by the different adjustment positions of 
that switch. Thus, a manufacturer could use the 
ISO parking light symbol, not specified by Stan- 
dard No. 101, for a particular position of a master 
lighting switch. Similarly, since Standard No. 101 
does not specify identification for a separate park- 
ing light control, a manufacturer could use the ISO 
parking light symbol to identify such a control. 

As noted above, the agency also proposed a 
change in the applicability of the symbol to iden- 
tification lamp and side marker lamp controls. 
Standard No. 101 currently specifies the symbol 
for clearance lamp controls, with a footnote in 



Table 1 indicating that the symbol should also be 
used when clearance lamps, identification lamps, 
and/or side marker lamps are controlled with one 
switch other than the headlamp switch. No sym- 
bols are specified for identification of separate con- 
trols for identification lamps or side marker lamps. 
The notice proposed that the symbol be specified 
for all controls operating these three types of 
lamps, except for a master lighting switch. This 
notice adopts the amendment as proposed. If 
separate controls are provided for these types of 
lamps, a manufacturer may use additional words 
or symbols for purposes of clarity. 

Shading of Symbols 

Tables 1 and 2 of Standard No. 101 include foot- 
notes that permit framed areas of certain symbols 
to be filled in. Recently, the ISO adopted variants 
of certain other symbols to essentially permit solid 
areas of those symbols to be in outline form. The 
November 1982 notice requested comments on 
whether manufacturers should be permitted to use 
those variant symbols. All of the comments re- 
ceived on this issue supported allowing the variant 
symbols. Some commenters stated that the ISO 
symbols shown in outline form are sufficiently 
recognizable. 

The agency agrees that the outline symbols are 
recognizable. Therefore, this notice permits those 
variant symbols to be used for the heating and/or 
air conditioning fan, the seat belt telltale, and fuel 
level. 

Horn Control 

In proposing a requirement that the horn con- 
trol be identified, the November 1982 notice ex- 
plained that NHTSA has received a number of 
complaints over the years about difficulty in 
locating the horn, especially in panic situations. 
The agency noted that since location of the horn is 
not standardized either by industry practice or by 
regulation, identification of the horn can provide 
important safety benefits at a minimal cost. The 
agency proposed that horn controls be identified 
by the ISO horn symbol, which is a picture of a 
horn (or bugle). 

Comments received on this issue were mixed. 
Some manufacturers supported the horn require- 
ment essentially as proposed. Several manufac- 
turers stated that identification is unnecessary 
when the horn is located in the usual place, i.e., on 
or near the steering wheel. Also, as indicated 



PART 571; SlOl- PRE 15 



above, some manufacturers opposed any expan- 
sion of Standard No. lOl's requirements. 

This notice adopts the requirement that the 
horn control be identified by the ISO horn symbol, 
with limited exceptions discussed below. The horn 
is an important device in accident avoidance. Ac- 
cordingly, the agency believes it is esential that 
drivers be able to quickly locate the horn control. 
In adopting this symbol, the agency concludes that 
it is clearly and intuitively recognizable. 

For other than heavy duty vehicles, the agency 
does not agree that identification is unnecessary 
when the horn control is located on or near the 
steering wheel. First, horn control location within 
the steering wheel area may vary significantly 
from vehicle to vehicle, making it difficult to find 
the horn control in an emergency situation. Second, 
to the extent that manufacturers locate the horn 
control elsewhere, e.g., on various stalks, drivers 
are less likely to expect the horn in what was once 
the traditional location. Moreover, the absence of a 
horn symbol in the steering wheel area will alert 
drivers to look elsewhere. Finally, controls other 
than the horn, such as a cruise control, may be 
located on or near the steering wheel, making it 
more difficult to find a horn control in that same 
general area. 

Some commenters expressed concern about how 
Standard No. lOl's requirement that symbols be 
perceptually upright might apply to horn controls 
located on the steering wheel. It was noted that it 
is impossible for these horn symbols to be percep- 
tually upright at all times. In response to these 
comments, the agency has included a provision 
that the horn symbol need be perceptually upright 
only when the vehicle, aligned to the manufac- 
turer's specification, has its wheels positioned for 
the vehicle to travel straight forward, i.e., when 
the steering wheel is centered. 

Volkswagen stated that the horns on some of its 
vehicles are actuated by pressing virtually 
anywhere on a large, cushioned pad extending 
over almost the entire area inside the steering 
wheel. That commenter stated that the proposal 
was unclear where a horn symbol should be placed 
in that situation. The agency does not agree that 
this is unclear. Standard No. 101 generally pro- 
vides that the identification for controls be placed 
on or adjacent to the control. Accordingly, Volks- 
wagen could place a single horn symbol anywhere 
on or adjacent to the cushioned pad. 

The November 1982 notice proposed to exclude 



narrow ring-type horn controls from the identifica- 
tion requirement since there may not be sufficient 
space on or adjacent to such controls for the horn 
symbol. One commenter pointed out that the re- 
quirements of Standard No. 203, Impact protection 
for the driver from the steering control system, 
have largely eliminated that type of control. That 
standard requires that the steering control system 
be constructed so that no components or at- 
tachments, including horn actuating mechanisms, 
can catch the driver's clothing or jewelry during 
normal driving maneuvers. While some ring-type 
horn control designs are prohibited by that re- 
quirement since they can catch the driver's 
clothing or jewelry during normal driving 
maneuvers, other designs do not have that prob- 
lem. The agency has therefore adopted that pro- 
posed exclusion. 

Several manufacturers commented that most 
heavy duty vehicles, unlike passenger cars, have 
both a standard horn and an air horn. The air horn 
is typically activated by pulling on a lanyard, i.e., 
chain, cable or rope, above the driver's head. Ac- 
cording to these commenters, placing a symbol on 
such a device would be difficult due to the small 
area of the lanyard. These commenters also stated 
that identification of such horns is unnecessary 
since professional heavy duty vehicle operators 
are familiar with this type of control. These com- 
menters also argued that the location of the stan- 
dard (electric) horn on these vehicles is stan- 
dardized in the center of the steering wheel hub 
and that identification of these horns is also un- 
necessary. 

The agency agrees with these commenters con- 
cerning air horns and has excluded lanyard- 
operated horns from Standard No. Id's identifica- 
tion requirements. The agency also agrees with 
the commenters concerning electric horns in 
heavy duty vehicles. Manufacturers of those vehi- 
cles have traditionally placed the electric horn in 
the center of the steering wheel hub and the agen- 
cy therefore sees no need to regulate in this area. 

Heating and Air Conditioning Controls 

Standard No. 101 currently requires identifica- 
tion for each function of any heating and air condi- 
tioning control, and for the extreme positions of 
any such control that regulates a function over a 
quantitative range. If a symbol is not specified by 
the standard for such a function, the identification 
must be in word form (unless color coding is used.) 



PART 571; SlOl -PRE 16 



Standard No. 101. Some commenters stated that 
the ECE version should not be permitted as an al- 
ternative, since it would be contrary to the antici- 
pated goal of harmonization. It was also pointed 
out that the ECE version is in a draft regulation 
and may not be finally adopted by that organization. 

GM agreed that it is desirable to have one sym- 
bol ultimately prevaU and suggested that NHTSA 
work within the ECE to resolve differences. GM 
argued, however, that resolving the differences is 
a harmonization issue rather than a safety issue 
and suggested that all three versions be permitted 
in the meantime. GM commented that all three 
versions are reasonably recognizable and similar 
enough in form that confusion should not result. 
Volkswagen similarly commented that the ver- 
sions are virtually identical. 

While it is true that the three versions are 
similar, the agency believes that for purposes of 
easy recognition only one should be specified. The 
leadtime provided by this notice gives adequate 
time for manufacturers to make the very minor 
changes necessitated by adoption of the ISO ver- 
sion, as proposed. 

Grumman Flxible suggested that the ECE sym- 
bol for parking lights be adopted in place of the 
clearance lamp symbol. (The ECE symbol is the 
same as the ISO symbol.) That commenter ap- 
peared to believe that the clearance lamp symbol 
must be used for the master lighting switch when 
it is adjusted so that all lights except the 
headlamps are on, or for a separate parking light 
control. The clearance lamp symbol need not be 
used in either instance. The clearance lamp symbol 
is only specified for a separate control for iden- 
tification, side marker and/or clearance lamps. As 
indicated above, manufacturers may, but need not, 
supplement the master lighting switch symbol 
with additional symbols to identify the lights 
operated by the different adjustment positions of 
that switch. Thus, a manufacturer could use the 
ISO parking light symbol, not specified by Stan- 
dard No. 101, for a particular position of a master 
lighting switch. Similarly, since Standard No. 101 
does not specify identification for a separate park- 
ing light control, a manufacturer could use the ISO 
parking light symbol to identify such a control. 

As noted above, the agency also proposed a 
change in the applicability of the symbol to iden- 
tification lamp and side marker lamp controls. 
Standard No. 101 currently specifies the symbol 
for clearance lamp controls, with a footnote in 



Table 1 indicating that the symbol should also be 
used when clearance lamps, identification lamps, 
and/or side marker lamps are controlled with one 
switch other than the headlamp switch. No sym- 
bols are specified for identification of separate con- 
trols for identification lamps or side marker lamps. 
The notice proposed that the symbol be specified 
for all controls operating these three types of 
lamps, except for a master lighting switch. This 
notice adopts the amendment as proposed. If 
separate controls are provided for these types of 
lamps, a manufacturer may use additional words 
or symbols for purposes of clarity. 

Shading of Symbols 

Tables 1 and 2 of Standard No. 101 include foot- 
notes that permit framed areas of certain symbols 
to be filled in. Recently, the ISO adopted variants 
of certain other symbols to essentially permit solid 
areas of those symbols to be in outline form. The 
November 1982 notice requested comments on 
whether manufacturers should be permitted to use 
those variant symbols. All of the comments re- 
ceived on this issue supported allowing the variant 
symbols. Some commenters stated that the ISO 
symbols shown in outline form are sufficiently 
recognizable. 

The agency agrees that the outline symbols are 
recognizable. Therefore, this notice permits those 
variant symbols to be used for the heating and/or 
air conditioning fan, the seat belt telltale, and fuel 
level. 

Horn Control 

In proposing a requirement that the horn con- 
trol be identified, the November 1982 notice ex- 
plained that NHTSA has received a number of 
complaints over the years about difficulty in 
locating the horn, especially in panic situations. 
The agency noted that since location of the horn is 
not standardized either by industry practice or by 
regulation, identification of the horn can provide 
important safety benefits at a minimal cost. The 
agency proposed that horn controls be identified 
by the ISO horn symbol, which is a picture of a 
horn (or bugle). 

Comments received on this issue were mixed. 
Some manufacturers supported the horn require- 
ment essentially as proposed. Several manufac- 
turers stated that identification is unnecessary 
when the horn is located in the usual place, i.e., on 
or near the steering wheel. Also, as indicated 



PART 571; SlOl -PRE 15 



above, some manufacturers opposed any expan- 
sion of Standard No. lOl's requirements. 

This notice adopts the requirement that the 
horn control be identified by the ISO horn symbol, 
with limited exceptions discussed below. The horn 
is an important device in accident avoidance. Ac- 
cordingly, the agency believes it is esential that 
drivers be able to quickly locate the horn control. 
In adopting this symbol, the agency concludes that 
it is clearly and intuitively recognizable. 

For other than heavy duty vehicles, the agency 
does not agree that identification is unnecessary 
when the horn control is located on or near the 
steering wheel. First, horn control location within 
the steering wheel area may vary significantly 
from vehicle to vehicle, making it difficult to find 
the horn control in an emergency situation. Second, 
to the extent that manufacturers locate the horn 
control elsewhere, e.g., on various stalks, drivers 
are less likely to expect the horn in what was once 
the traditional location. Moreover, the absence of a 
horn symbol in the steering wheel area will alert 
drivers to look elsewhere. Finally, controls other 
than the horn, such as a cruise control, may be 
located on or near the steering wheel, making it 
more difficult to find a horn control in that same 
general area. 

Some commenters expressed concern about how 
Standard No. lOl's requirement that symbols be 
perceptually upright might apply to horn controls 
located on the steering wheel. It was noted that it 
is impossible for these horn symbols to be percep- 
tually upright at all times. In response to these 
comments, the agency has included a provision 
that the horn symbol need be perceptually upright 
only when the vehicle, aligned to the manufac- 
turer's specification, has its wheels positioned for 
the vehicle to travel straight forward, i.e., when 
the steering wheel is centered. 

Volkswagen stated that the horns on some of its 
vehicles are actuated by pressing virtually 
anywhere on a large, cushioned pad extending 
over almost the entire area inside the steering 
wheel. That commenter stated that the proposal 
was unclear where a horn symbol should be placed 
in that situation. The agency does not agree that 
this is unclear. Standard No. 101 generally pro- 
vides that the identification for controls be placed 
on or adjacent to the control. Accordingly, Volks- 
wagen could place a single horn symbol anywhere 
on or adjacent to the cushioned pad. 

The November 1982 notice proposed to exclude 



narrow ring-type horn controls from the identifica- 
tion requirement since there may not be sufficient 
space on or adjacent to such controls for the horn 
symbol. One commenter pointed out that the re- 
quirements of Standard No. 203, Impact protection 
for the driver from the steering control system, 
have largely eliminated that type of control. That 
standard requires that the steering control system 
be constructed so that no components or at- 
tachments, including horn actuating mechanisms, 
can catch the driver's clothing or jewelry during 
normal driving maneuvers. While some ring-type 
horn control designs are prohibited by that re- 
quirement since they can catch the driver's 
clothing or jewelry during normal driving 
maneuvers, other designs do not have that prob- 
lem. The agency has therefore adopted that pro- 
posed exclusion. 

Several manufacturers commented that most 
heavy duty vehicles, unlike passenger cars, have 
both a standard horn and an air horn. The air horn 
is typically activated by pulling on a lanyard, i.e., 
chain, cable or rope, above the driver's head. Ac- 
cording to these commenters, placing a symbol on 
such a device would be difficult due to the small 
area of the lanyard. These commenters also stated 
that identification of such horns is unnecessary 
since professional heavy duty vehicle operators 
are familiar with this type of control. These com- 
menters also argued that the location of the stan- 
dard (electric) horn on these vehicles is stan- 
dardized in the center of the steering wheel hub 
and that identification of these horns is also un- 
necessary. 

The agency agrees with these commenters con- 
cerning air horns and has excluded lanyard- 
operated horns from Standard No. lOl's identifica- 
tion requirements. The agency also agrees with 
the commenters concerning electric horns in 
heavy duty vehicles. Manufacturers of those vehi- 
cles have traditionally placed the electric horn in 
the center of the steering wheel hub and the agen- 
cy therefore sees no need to regulate in this area. 

Heating and Air Conditioning Controls 

Standard No. 101 currently requires identifica- 
tion for each function of any heating and air condi- 
tioning control, and for the extreme positions of 
any such control that regulates a function over a 
quantitative range. If a symbol is not specified by 
the standard for such a function, the identification 
must be in word form (unless color coding is used.) 



PART 571; SlOl- PRE 16 



Standard No. 101 currently specifies symbols for 
several functions of a heating and air conditioning 
system, including the fan, defrosting and defog- 
ging, and rear window defrosting and defogging. 
The November 1982 NPRM proposed to add sev- 
eral ISO symbols to cover additional functions, in- 
cluding heating, air conditioning, various types of 
vents, and heated seat. 

The agency received numerous comments which 
were opposed to adding these symbols to Standard 
No. 101. Some commenters stated that the sym- 
bols in question were inexplicit and had been 
adopted hastily by the ISO, without testing for 
recognizability. According to some commenters, 
there are efforts within the ISO to change the sym- 
bols. Concern was also expressed that the symbols 
are difficult to apply to many of the complex 
heating and air conditioning systems in use today 
or planned for the future. Several manufacturers 
submitted drawings of heating and air condition- 
ing systems to illustrate the problems associated 
with the application of the proposed symbols. GM 
stated that questions of interpretation raise the 
concern that these particular proposed changes 
are not objective, since manufacturers would not 
have the requisite assurance that they have met 
the standard with any specific design. 

Ford requested that control? for automatic 
temperature control systems be exempted from 
the proposed requirements. Other manufacturers 
expressed concern about how to identify controls 
with multiple functions. 

Volkswagen recommended that manufacturers 
be permitted to use words or symbols, of their own 
choosing, for heating and air conditioning controls. 
That company argued that such flexibility would 
result in more meaningful symbols being utilized 
for various functions. Volkswagen acknowledged 
that such flexibility could result in lack of uniform 
use of the same symbol for the same control by all 
manufacturers and in use of symbols not consis- 
tent with international recommendations. That 
commenter did not believe that these would be 
significant problems, however, noting among other 
things that there is so much variety in heating and 
air conditioning systems that each car would still 
be unique, even if the proposed symbols were used. 

This notice adopts an approach along the lines 
suggested by Volkswagen. NHTSA continues to 
believe that, as currently required, each function 
of a heating or air conditioning system should be 
identified. Based on its review of comments. 



however, the agency agrees that the proposed 
symbols are not adequate for defining the func- 
tions of all heating and air conditioning systems. 
While the agency considered simply maintaining 
the current requirement that words be used for 
functions where symbols are not specified, the 
agency has decided instead that both safety and 
cost reduction through harmonization are best 
served by permitting manufacturers to identify 
such functions by words or symbols, with the 
specific words or symbols at the discretion of the 
manufacturer. 

As discussed above, the agency has previously 
concluded that symbols can convey information 
more quickly and with less chance of human error 
than words, resulting in safety benefits. Use of 
symbols appears to be particularly appropriate for 
identifying some functions of complex heating and 
air conditioning systems. For example, a relatively 
simple symbol can convey information about such 
things as the direction of air flow more readily and 
clearly than words. 

The agency continues to believe that, for pur- 
poses of optimum recognizability, standardized in- 
ternational symbols should be used wherever 
possible. In the case of symbols for some functions 
of heating and air conditioning systems, however, 
where the agency has concluded that standardized 
symbols are not fully or adequately developed, the 
agency considers it appropriate to permit manu- 
facturers to use symbols of their own choosing. 
This action may not only result in safety benefits, 
as manufacturers develop and use symbols for 
these functions, but also promotes harmonization. 
Manufacturers which produce vehicles for sale in 
non-English-speaking countries using symbols wUl 
not need to develop special designs using English 
words. 

The agency will monitor the continued develop- 
ment of international symbols in this area, as well 
as the symbols actually used by manufacturers on 
their vehicles' heating and air conditioning 
systems. If circumstances should warrant, the 
agency may consider specifying standardized sym- 
bols in the future. 

The agency declines to exempt automatic tem- 
perature control systems from the standard's iden- 
tification requirements. The need for identification 
of controls for this type of system is no different 
than for traditional heating and air conditioning 
systems. However, the option of using words or 
symbols of the manufacturer's choosing should 



PART 571; SlOl- PRE 17 



provide ample flexibility in identifying the con- 
trols of these systems. 

Manufacturers will continue to be required to 
use the symbols specified by Standard No. 101 for 
the fan, windshield defrosting and defogging, and 
rear window defrosting and defogging. The option 
of using words or symbols of the manufacturer's 
choosing applies only to other functions. The addi- 
tion of this option does not impose any new 
requirements since manufacturers are already re- 
quired to identify those other functions by words. 

Interpretive Amendments 

This notice adopts several interpretive amend- 
ments, as proposed by the November 1982 notice 
and in accord with previous agency interpreta- 
tions. Two footnotes concerning the turn signal 
control symbol are added to Table 1. That symbol, 
a pair of horizontal arrows pointing to the left and 
right, is ordinarily a single symbol. One footnote 
makes it clear that the two arrows may be consi- 
dered separate symbols where there are indepen- 
dent controls for the left and right turn signals. 
The other footnote makes it clear that framed 
areas of that symbol or symbols may be filled in. 

Section S5.3.5 of Standard No. 105 is amended to 
indicate that the words "Brake Fluid" need not be 
used for a separate indicator lamp for brake fluid 
where a vehicle uses hydraulic system mineral oil 
rather than conventional brake fluid. (A manufac- 
turer is instead required to use the word "Brake" 
and appropriate additional labeling.) 

This notice also makes related interpretive 
amendments of a minor nature in section S5.3.5 of 
Standard No. 105 and Table 2 of Standard No. 101 
that were not proposed by the November 1982 
notice. Section S5.3.5 currently requires that a 
malfunction in an anti lock system be identified by 
the word "Antilock". Table 2 specifies the same 
word but in a hyphenated form, i.e., "Anti-Lock." 
This notice amends the two standards to make it 
clear that a manufacturer may use either form of 
the word. Since these amendments are interpre- 
tive, notice and comment is not required. 

The November 1982 notice also proposed other 
changes in section S5.3.5 of Standard No. 105. 
While the agency is not adopting any other 
substantive changes in that section at this time, it 
is adopting a new format for that section along the 
lines proposed by that notice. 

The November 1982 notice proposed to drop the 
words listed by column 2 of Table 1 for controls for 



which a symbol is also specified. Section S5.2.1(a) 
provides that while the symbol specified by Table 
1 for such a control is mandatory, the words listed 
by column 2 may be used in addition to the symbol. 
That same section provides further, however, that 
any additional words or symbols may be used at 
the manufacturer's discretion for purposes of clari- 
ty. Since manufacturers may use any words in ad- 
dition to the required symbol, the provision that a 
manufacturer may use the words specified by col- 
umn 2 has no legal effect. Accordingly, this notice 
drops those words from column 2 and makes a con- 
forming amendment to section S5.2.1(a). 

Leadtime 

The amendments are effective immediately. 
However, some amendments are of an optional 
nature until September 1, 1987. The agency finds 
good cause for an immediate effective date for the 
optional identification requirements since the 
amendments relieve restrictions, while reducing 
compliance costs and promoting safety. 

The November 1982 notice proposed an effec- 
tive date of September 1, 1985, for mandatory use 
of the new symbols. Several commenters sug- 
gested that date was too early. In promulgating 
this final rule, the agency has determined that a 
date of September 1, 1987 provides adequate lead- 
time. The agency also finds it is in the public in- 
terest to establish such a relatively long leadtime 
for mandatory use of the new symbols, given the 
nature of the changes and since such a leadtime 
minimizes compliance costs. 

In consideration of the foregoing, §571.101 and 
§571.105, Chapter V of Title 49, Code of Federal 
Regulations, are amended as follows: 

%571.101 [AmendedJ 

1. Section S5 is revised to read as follows: 

S5. Requirements, (a) Except as provided in 
paragraph (b) of this section, each passenger car, 
multipurpose passenger vehicle, truck and bus 
manufactured with any control listed in S5.1 or in 
column 1 of Table 1, and each passenger car, multi- 
purpose passenger vehicle and truck or bus less 
than 10,000 pounds GVWR with any display listed 
in S5.1 or in column 1 of Table 2, shall meet the re- 
quirements of this standard for the location, identi- 
fication, and illumination of such control or display. 

(b) For vehicles manufactured before Septem- 
ber 1, 1987, a manufacturer may, at its option — 

(1) Meet the requirements in this standard to use 
identifying words or abbreviation or identifying 



PART 571; SlOl- PRE 18 



Standard No. 101 currently specifies symbols for 
several functions of a heating and air conditioning 
system, including the fan, defrosting and defog- 
ging, and rear window defrosting and defogging. 
The November 1982 NPRM proposed to add sev- 
eral ISO symbols to cover additional functions, in- 
cluding heating, air conditioning, various types of 
vents, and heated seat. 

The agency received numerous comments which 
were opposed to adding these symbols to Standard 
No. 101. Some commenters stated that the sym- 
bols in question were inexplicit and had been 
adopted hastily by the ISO, without testing for 
recognizability. According to some commenters, 
there are efforts within the ISO to change the sym- 
bols. Concern was also expressed that the symbols 
are difficult to apply to many of the complex 
heating and air conditioning systems in use today 
or planned for the future. Several manufacturers 
submitted drawings of heating and air condition- 
ing systems to illustrate the problems associated 
with the application of the proposed symbols. GM 
stated that questions of interpretation raise the 
concern that these particular proposed changes 
are not objective, since manufacturers would not 
have the requisite assurance that they have met 
the standard with any specific design. 

Ford requested that control? for automatic 
temperature control systems be exempted from 
the proposed requirements. Other manufacturers 
expressed concern about how to identify controls 
with multiple functions. 

Volkswagen recommended that manufacturers 
be permitted to use words or symbols, of their own 
choosing, for heating and air conditioning controls. 
That company argued that such flexibility would 
result in more meaningful symbols being utilized 
for various functions. Volkswagen acknowledged 
that such flexibUity could result in lack of uniform 
use of the same symbol for the same control by all 
manufacturers and in use of symbols not consis- 
tent with international recommendations. That 
commenter did not believe that these would be 
significant problems, however, noting among other 
things that there is so much variety in heating and 
air conditioning systems that each car would still 
be unique, even if the proposed symbols were used. 

This notice adopts an approach along the lines 
suggested by Volkswagen. NHTSA continues to 
believe that, as currently required, each function 
of a heating or air conditioning system should be 
identified. Based on its review of comments, 



however, the agency agrees that the proposed 
symbols are not adequate for defining the func- 
tions of all heating and air conditioning systems. 
While the agency considered simply maintaining 
the current requirement that words be used for 
functions where symbols are not specified, the 
agency has decided instead that both safety and 
cost reduction through harmonization are best 
served by permitting manufacturers to identify 
such functions by words or symbols, with the 
specific words or symbols at the discretion of the 
manufacturer. 

As discussed above, the agency has previously 
concluded that symbols can convey information 
more quickly and with less chance of human error 
than words, resulting in safety benefits. Use of 
symbols appears to be particularly appropriate for 
identifying some functions of complex heating and 
air conditioning systems. For example, a relatively 
simple symbol can convey information about such 
things as the direction of air flow more readUy and 
clearly than words. 

The agency continues to believe that, for pur- 
poses of optimum recognizability, standardized in- 
ternational symbols should be used wherever 
possible. In the case of symbols for some functions 
of heating and air conditioning systems, however, 
where the agency has concluded that standardized 
symbols are not fully or adequately developed, the 
agency considers it appropriate to permit manu- 
facturers to use symbols of their own choosing. 
This action may not only result in safety benefits, 
as manufacturers develop and use symbols for 
these functions, but also promotes harmonization. 
Manufacturers which produce vehicles for sale in 
non-English-speaking countries using symbols will 
not need to develop special designs using English 
words. 

The agency will monitor the continued develop- 
ment of international symbols in this area, as well 
as the symbols actually used by manufacturers on 
their vehicles' heating and air conditioning 
systems. If circumstances should warrant, the 
agency may consider specifying standardized sym- 
bols in the future. 

The agency declines to exempt automatic tem- 
perature control systems from the standard's iden- 
tification requirements. The need for identification 
of controls for this type of system is no different 
than for traditional heating and air conditioning 
systems. However, the option of using words or 
symbols of the manufacturer's choosing should 



PART 571; SlOl -PRE 17 



provide ample flexibility in identifying the con- 
trols of these systems. 

Manufacturers will continue to be required to 
use the symbols specified by Standard No. 101 for 
the fan, windshield defrosting and defogging, and 
rear window defrosting and defogging. The option 
of using words or symbols of the manufacturer's 
choosing applies only to other functions. The addi- 
tion of this option does not impose any new 
requirements since manufacturers are already re- 
quired to identify those other functions by words. 

Interpretive Amendments 

This notice adopts several interpretive amend- 
ments, as proposed by the November 1982 notice 
and in accord with previous agency interpreta- 
tions. Two footnotes concerning the turn signal 
control symbol are added to Table 1. That symbol, 
a pair of horizontal arrows pointing to the left and 
right, is ordinarily a single symbol. One footnote 
makes it clear that the two arrows may be consi- 
dered separate symbols where there are indepen- 
dent controls for the left and right turn signals. 
The other footnote makes it clear that framed 
areas of that symbol or symbols may be filled in. 

Section S5.3.5 of Standard No. 105 is amended to 
indicate that the words "Brake Fluid" need not be 
used for a separate indicator lamp for brake fluid 
where a vehicle uses hydraulic system mineral oil 
rather than conventional brake fluid. (A manufac- 
turer is instead required to use the word "Brake" 
and appropriate additional labeling.) 

This notice also makes related interpretive 
amendments of a minor nature in section S5.3.5 of 
Standard No. 105 and Table 2 of Standard No. 101 
that were not proposed by the November 1982 
notice. Section S5.3.5 currently requires that a 
malfunction in an anti lock system be identified by 
the word "Antilock". Table 2 specifies the same 
word but in a hyphenated form, i.e., "Anti-Lock." 
This notice amends the two standards to make it 
clear that a manufacturer may use either form of 
the word. Since these amendments are interpre- 
tive, notice and comment is not required. 

The November 1982 notice also proposed other 
changes in section S5.3.5 of Standard No. 105. 
WhUe the agency is not adopting any other 
substantive changes in that section at this time, it 
is adopting a new format for that section along the 
lines proposed by that notice. 

The November 1982 notice proposed to drop the 
words listed by column 2 of Table 1 for controls for 



which a symbol is also specified. Section S5.2.1{a) 
provides that while the symbol specified by Table 
1 for such a control is mandatory, the words listed 
by column 2 may be used in addition to the symbol. 
That same section provides further, however, that 
any additional words or symbols may be used at 
the manufacturer's discretion for purposes of clari- 
ty. Since manufacturers may use any words in ad- 
dition to the required symbol, the provision that a 
manufacturer may use the words specified by col- 
umn 2 has no legal effect. Accordingly, this notice 
drops those words from column 2 and makes a con- 
forming amendment to section S5.2.1(a). 

Leadtime 

The amendments are effective immediately. 
However, some amendments are of an optional 
nature until September 1, 1987. The agency finds 
good cause for an immediate effective date for the 
optional identification requirements since the 
amendments relieve restrictions, while reducing 
compliance costs and promoting safety. 

The November 1982 notice proposed an effec- 
tive date of September 1, 1985, for mandatory use 
of the new symbols. Several commenters sug- 
gested that date was too early. In promulgating 
this final rule, the agency has determined that a 
date of September 1, 1987 provides adequate lead- 
time. The agency also finds it is in the public in- 
terest to establish such a relatively long leadtime 
for mandatory use of the new symbols, given the 
nature of the changes and since such a leadtime 
minimizes compliance costs. 

In consideration of the foregoing, §571.101 and 
§571.105, Chapter V of Title 49, Code of Federal 
Regulations, are amended as follows: 

§571.101 [Amended] 

1. Section S5 is revised to read as follows: 

S5. Requirements, (a) Except as provided in 
paragraph (b) of this section, each passenger car, 
multipurpose passenger vehicle, truck and bus 
manufactured with any control listed in S5.1 or in 
column 1 of Table 1, and each passenger car, multi- 
purpose passenger vehicle and truck or bus less 
than 10,000 pounds GVWR with any display listed 
in S5.1 or in column 1 of Table 2, shall meet the re- 
quirements of this standard for the location, identi- 
fication, and illumination of such control or display. 

(b) For vehicles manufactured before Septem- 
ber 1, 1987, a manufacturer may, at its option — 

(1) Meet the requirements in this standard to use 
identifying words or abbreviation or identifying 



PART 571; SlOl -PRE 18 



symbol for a control by using those specified in 
Table 1(a) instead of Table 1. If none are specified 
in Table 1(a), none need be used for the control. 

(2) Meet the requirements in this standard to 
use identifying words or abbreviation or identify- 
ing symbol for a display by using those specified in 
Table 2(a) instead of Table 2. If none are specified 
in Table 2(a), none need be used for the display. 

2. Section S5.2.1(a) is revised to read as follows: 
(a) Except as specified in S5.2.1(b), any hand- 
operated control listed in column 1 of Table 1 that 
has a symbol designated in column 3 shall be iden- 
tified by that symbol. Any such control for which 
no symbol is shown in Table 1 shall be identified by 
the word or abbreviation shown in column 2, if 
such word or abbreviation is shown. Words or 
symbols in addition to the required symbol, word 
or abbreviation may be used at the manufacturer's 
discretion for the purpose of clarity. Any such con- 
trol for which column 2 of Table 1 and/or column 3 
of Table 1 specifies "Mfr. Option" shall be iden- 
tified by the manufacturer's choice of a symbol, 
word or abbreviation, as indicated by that speci- 
fication in column 2 and/or column 3. The iden- 
tification shall be placed on or adjacent to the con- 
trol. The identification shall, under the conditions 
of S6, be visible to the driver and, except as pro- 
vided in S5.2.1.1 and S5.2.1.2, appear to the driver 
perceptually upright. 

3. Section S5.2.1.1 is revised to read as follows: 
S5.2.1.1 The identification of a master lighting 

switch or headlamp and taU lamp control that ad- 
justs control and display illumination by means of 
rotation, or of any other rotating control that does 
not have an off position, need not appear to the 
driver perceptually upright. The identification of a 
horn control need not appear to the driver percep- 
tually upright except when the vehicle, aligned to 
the manufacturer's specifications, has its wheels 
positioned for the vehicle to travel in a straight 
forward direction. 

4. The second sentence of section S5.2.2 is re- 
vised to read as follows: 

If this identification is not specified in Tables 1 
or 2, it shall be in word or symbol form unless color 
coding is used. 

5. A new Table 1 is added following section S6 
to read as set forth below. 

6. The existing Table 1 is redesignated Table 
1(a). 

7. A new Table 2 is added following Table 1(a) to 
read as set forth below. 



8. The existing Table 2 is redesignated Table 
2(a). 

%57 1.105 [Amended] 

1. Section S5.3.5 is revised to read as follows: 

S5.3.5(a) Each indicator lamp shall display word 
or words, in accordance with the requirements of 
Standard No. 101 (49 CFR 571.101) and/or this sec- 
tion, which shall be legible to the driver in daylight 
when lighted. The words shall have letters not less 
than 1/8-inch high. Words in addition to those re- 
quired by Standard No. 101 and/or this section and 
symbols may be provided for purposes of clarity. 

(b) If a single common indicator is used, the 
lamp shall display the word "Brake". The letters 
and background of a single common indicator shall 
be of contrasting colors, one of which is red. 

(cKl) If separate indicator lamps are used for 
one or more than one of the functions described in 
S5.3.1(a) through S5.3.1(d), the display shall, except 
as provided in (cKlKA) through (D) of this section, 
include the word "Brake" and appropriate addi- 
tional labeling. 

(A) If a separate indicator lamp is provided for 
gross loss of pressure, the words "Brake Pressure" 
shall be used for S5.3.1(a). 

(B) If a separate indicator lamp is provided for 
low brake fluid, the words "Brake Fluid" shall be 
used for S5.3.1(b), except for vehicles using 
hydraulic system mineral oil. 

(C) If a separate indicator lamp is provided for 
an anti lock system, the single word "Antilock" or 
"Anti-Lock" may be used for S5.3.1(c). 

(D) If a separate indicator lamp is provided for 
application of the parking brake, the single word 
"Park" may be used for S5.3.1(d). 

(2) Except for a separate indicator lamp for an 
antilock system, the letters and background of 
each separate indicator lamp shall be of con- 
trasting colors, one of which is red. The letters and 
background of a separate indicator lamp for an 
anti lock system shall be of contrasting colors, one 
of which is yellow. 

Issued on July 24, 1984 



Diane K. Steed 
Administrator 

49 FR 30191 
July 27, 1984 



PART 571; SlOl- PRE 19 



Table 1 
Identification and Illumination of Controls 



Column 1 


Column 2 


Column 3 


Column 4 


Hand Operated Controls 


Ident'fying Words 
or Abbreviation 


Identifying 
Symbol 


Illumination 


• 
Master Liphiing 
Switch 




-Pr 


^^^^"' 






Headlamps and 
Tail lamps 


(Mfr Option)' 


(Mfr Option)' 






Horn 




kr ' 








Turn Signal 




<">: 








Hazard Warning 
Signal 




A' 


Yes 




Windshield Wiping 
System 




V 


Yes 




Windshield Washing 
System 




<p 


Yes 




Windshield Washing 
and Wiping Combined 




jp^ 

^ 


Yes 




Heating and or Air 
Conditioning Fan 




*.^ 


Yes 




Windshield Defrosting 
and Defogging System 




^ 


Yes 




Rear Window Defrosting 
and Defogging System 




(¥1 


Yes 




jjj 


Identification, Side 

Marker and or Clearance 

Lamps 




-00- 


Yes 




Manual Choke 


Choke 










Engine Start 


Engine Start^ 










Engine Stop 


Engine Stop' 




Yes 




Hand Thronie 


Throttle 










Automatic Vehicle Speed 


(Mfr Option) 




Yes 




Heating and Air 

Conditioning 

System 


(Mfr Option) 


(Mfr Option) 


Yes 



' Use when engine control is separate from the key locking system. 
' Separate identification not required if controlled by master lighting switch. 

' The pair of arrows is a single symbol. When the controls for left and right turn operate independently, 
however, the two arrows may be considered separate symbols and be spaced accordingly 

* Identification not required for vehicles with a GVWR greater than 10,000 lbs., or for narrow ring-type controls. 

* Framed areas may be filled 

PART 571: SlOl-PRE 20 



symbol for a control by using those specified in 
Table 1(a) instead of Table 1. If none are specified 
in Table 1(a), none need be used for the control. 

(2) Meet the requirements in this standard to 
use identifying words or abbreviation or identify- 
ing symbol for a display by using those specified in 
Table 2(a) instead of Table 2. If none are specified 
in Table 2(a), none need be used for the display. 

2. Section S5.2.1(a) is revised to read as follows: 
(a) Except as specified in S5.2.1(b), any hand- 
operated control listed in column 1 of Table 1 that 
has a symbol designated in column 3 shall be iden- 
tified by that symbol. Any such control for which 
no symbol is shown in Table 1 shall be identified by 
the word or abbreviation shown in column 2, if 
such word or abbreviation is shown. Words or 
symbols in addition to the required symbol, word 
or abbreviation may be used at the manufacturer's 
discretion for the purpose of clarity. Any such con- 
trol for which column 2 of Table 1 and/or column 3 
of Table 1 specifies "Mfr. Option" shall be iden- 
tified by the manufacturer's choice of a symbol, 
word or abbreviation, as indicated by that speci- 
fication in column 2 and/or column 3. The iden- 
tification shall be placed on or adjacent to the con- 
trol. The identification shall, under the conditions 
of S6, be visible to the driver and, except as pro- 
vided in S5.2.1.1 and S5.2.1.2, appear to the driver 
perceptually upright. 

3. Section S5.2.1.1 is revised to read as follows: 
S5.2.1.1 The identification of a master lighting 

switch or headlamp and taU lamp control that ad- 
justs control and display illumination by means of 
rotation, or of any other rotating control that does 
not have an off position, need not appear to the 
driver perceptually upright. The identification of a 
horn control need not appear to the driver percep- 
tually upright except when the vehicle, aligned to 
the manufacturer's specifications, has its wheels 
positioned for the vehicle to travel in a straight 
forward direction. 

4. The second sentence of section S5.2.2 is re- 
vised to read as follows: 

If this identification is not specified in Tables 1 
or 2, it shall be in word or symbol form unless color 
coding is used. 

5. A new Table 1 is added following section S6 
to read as set forth below. 

6. The existing Table 1 is redesignated Table 
1(a). 

7. A new Table 2 is added following Table 1(a) to 
read as set forth below. 



8. The existing Table 2 is redesignated Table 
2(a). 

%571.105 [Amended] 

1. Section S5.3.5 is revised to read as follows: 

S5.3.5(a) Each indicator lamp shall display word 
or words, in accordance with the requirements of 
Standard No. 101 (49 CFR 571.101) and/or this sec- 
tion, which shall be legible to the driver in daylight 
when lighted. The words shall have letters not less 
than 1/8-inch high. Words in addition to those re- 
quired by Standard No. 101 and/or this section and 
symbols may be provided for purposes of clarity. 

(b) If a single common indicator is used, the 
lamp shall display the word "Brake". The letters 
and background of a single common indicator shall 
be of contrasting colors, one of which is red. 

(cKl) If separate indicator lamps are used for 
one or more than one of the functions described in 
S5.3.1(a) through S5.3.1(d), the display shall, except 
as provided in (cKlKA) through (D) of this section, 
include the word "Brake" and appropriate addi- 
tional labeling. 

(A) If a separate indicator lamp is provided for 
gross loss of pressure, the words "Brake Pressure" 
shall be used for S5.3.1(a). 

(B) If a separate indicator lamp is provided for 
low brake fluid, the words "Brake Fluid" shall be 
used for S5.3.1(b), except for vehicles using 
hydraulic system mineral oil. 

(C) If a separate indicator lamp is provided for 
an anti lock system, the single word "Antilock" or 
"Anti-Lock" may be used for S5.3.1(c). 

(D) If a separate indicator lamp is provided for 
application of the parking brake, the single word 
"Park" may be used for S5.3.1(d). 

(2) Except for a separate indicator lamp for an 
antilock system, the letters and background of 
each separate indicator lamp shall be of con- 
trasting colors, one of which is red. The letters and 
background of a separate indicator lamp for an 
anti lock system shall be of contrasting colors, one 
of which is yellow. 

Issued on July 24, 1984 



Diane K. Steed 
Administrator 

49 FR 30191 
July 27, 1984 



PART 571; SlOl -PRE 19 



Table 1 
Identification and Illumination of Controls 



Column 1 


Column 2 


Column 3 


Column 4 


Hand Operated Controls 


Identifying Words 
or Abbreviation 


Identifying 
Symbol 


Illumination 


• 
Master Ligiiling 
Switch 




-Pr 








Headlamps and 
Tail lamps 


(Mfr Option)-' 


(Mfr Option)' 






Horn 




kr ' 








Turn Signal 




<"^: 








Hazard Warning 
Signal 




A' 


Yes 




Windshield Wiping 
System 




V 


Yes 




Windshield Washing 
System 




.p^ 

^ 


Yes 




Windshield Washing 
and Wiping Combined 






Yes 




Heating and or Air 
Conditioning Fan 




9t.^ 


Yes 




Windshield Defrosting 
and Defogging System 




<W 


Yes 




Rear Window Defrosting 
and Defogging System 






Yes 


41 




))) 


Identification, Side 

Marker and or Clearance 

Lamps 




-00- 


Yes 




Manual Choke 


Choke 










Engine Start 


Engine Start' 










Engine Stop 


Engine Stop' 




Yes 




Hand Throttle 


Throttle 










Automatic Vehicle Speed 


(Mfr OptionI 




Yes 




Heating and Air 

Conditioning 

System 


(Mfr Option) 


(Mfr Option) 


Yes 



' Use when engine control is separate from the key locking system 

' Separate identification not required if controlled by master lighting switch. 

' The pair of arrows is a single symbol When the controls for left and right turn operate independently, 
however, the two arrows maybe considered separate symbols and be spaced accordingly 
Identification not required for vehicles with a GVWR greater than 10,000 lbs., or for narrow ring-type controls. 

' Framed areas may be filled. 

PART 571; SlOl-PRE 20 



Table z 



Identification and Illumination of Displays 



Column 1 


Column 2 


Column 3 


Column 4 


Column 5 


Display 

• 


Telltale 
Color 


Identifying Words 
or Abbreviation 


Identifying 
Symbol 


Illumination 


Turn Signal 
Telltale 


Green 


Also see 
FMVSS 108 


«*; 




Hazard Warning 
Telltale 


Red" 


Also see 
FMVSS 108 


a; 




Seat 

Belt 

Telltale 


Red" 


Also see 
FMVSS 208 


^rr o' ^^ 




Fuel Level 
Telltale 


Yellow 


Fuel 


».B 


k— ^— ^— ^— ^— «■» 

Yes 


Gauge 




Oil Pressure 
Telltale 


Red" 


Oil 


«&r. 


Yes 


Gauge 




Coolant Temperature 
Telltale 


Red" 


Temp 


J, 


Yes 


Gauge 




Electrical Charge 
Telltale 


Red" 


Volts, Charge 
or Amp 


n 


Yes 


Gauge 






Highbeam 
Telltale 


Blue or 
Green" 


Also see 
FMVSS 108 


ID" 




Malfunction in 
Anti-Lock or 


Yellow 


Antilock or Anti-lock 
Also see FMVSS 105 






Brake System 


Red" 


Brake. Also 
see FMVSS 105 






Brake Air Pressure 
Position Telltale 


Red" 


Brake Air Also 
see FMVSS 121 






Speedometer 




MPH^ 




Yes 


Odometer 




3 






Automatic Gear 
Position 




Also see 
FMVSS 102 




Ves 



' The pair of arrows is a single symbol. When the indicator for left and right turn operate independently, however, the two arrows 

will be considered separate symbols and may be spaced accordingly. 

Not required when arrows of turn signal tell-tales that otherwise operate independently flash simultaneously as hazard warning 

tell-tale. 
' If the odometer indicates kilometers, then "KILOMETERS" or "km" shall appear, othenwise, no identification is required. 

Red can be red-orange. Blue can be blue-green. 

If the speedometer is graduated in miles per hour and in kilometers per hour, the identifying words or abbreviations shall be 

"MPH and km/h" in any combination of upper or lower case letters. 

Framed areas may be filled. 

PART 571; SlOl-PRE 21-22 



iBDie £ 



Identification and illumination of Displays 



Column 1 


Column 2 


Column 3 


Column 4 


Column 5 


Display 

• 


Telltale 
Color 


Identifying Words 
or Abbreviation 


Identifying 
Symbol 


Illumination 


Turn Signal 
Telltale 


Green 


Also see 
FMVSS 108 


«*: 




Hazard Warning 
Telltale 


Rerf' 


Also see 
FMVSS 108 


a: 




Seat 
Belt 

Telltale 


Red* 


Also see 
FMVSS 208 


^rr " ^cr 




Fuel Level 
Telltale 


Yellow 


Fuel 


B.a 


Yes 


Gauge 




Oil Pressure 
Telltale 


Red* 


Oil 


*e:7*. 


Yes 


Gauge 






Coolant Temperature 
Telltale 


Red* 


Temp 


J, 


Yes 


Gauge 




Electrical Charge 
Telltale 


Red* 


Volts, Charge 
or Amp 


n\ 


Yes 


Gauge 






Highbeam 
Telltale 


Blue or 
Greerf 


Also see 
FMVSS 108 


ID' 




Malfunction in 
Anti-Lock or 


Yellow 


Antilock or Anti-lock 
Also see FMVSS 105 






Brake System 


Red* 


Brake. Also 
see FMVSS 105 






Brake Air Pressure 
Position Telltale 


Red* 


Brake Air. Also 
see FMVSS 121 






Speedometer 




MPH^ 




Yes 


Odometer 




3 






Automatic Gear 




Also see 
FMVSS 102 




Yes 



' The pair of arrows is a sir>gle symbol. When the indicator for left and right turn operate independently, however, the two arrows 

will be considered separate symbols and may be spaced accordingly. 
' Not required when arrows of turn signal tell-tales that otherwise operate independently flash simultaneously as hazard warning 

tell-tale. 
1^ If tt>e odometer indicates kilometers, then "KILOMETERS" or "km" shall appear, otherwise, no identification is required. 

Red can be red-orange. Blue can be blue-green. 
^ If the speedometer is graduated in miles per hour and in kilometers per hour, the identifying words or abbreviations shall be 

"MPH and km/h" in any combination of upper or lower case letters. 

Framed areas may be filled. 

PART 571; 8101 -PRE 21-22 



FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 101 



Controls and Displays 

(Docket No. 1-18; Notice 13) 



51. Scope. This standard specifies require- 
ments for the location, identification, and illumina- 
tion of motor vehicle controls and displays. 

52. Purpose. The purpose of this standard is to 
ensure the accessibility and visibility of motor vehi- 
cle controls and displays and to facilitate their 
selection under daylight and nighttime conditions, 
in order to reduce the safety hazards caused by the 
diversion of the driver's attention from the driving 
task, and by mistakes in selecting controls. 

53. Application. This standard applies to 
passenger cars, multipurpose passenger vehicles, 
trucks, and buses. 

54. Definitions. 

"Telltale" means a display that indicates, by 
means of a light-emitting signal, the actuation of a 
device, a correct or defective functioning or condi- 
tion, or a failure to function. 

"Gauge" means a display that is listed in S5.1 or 
in Table 2 and is not a telltale. 

"Informational readout display" means a display 
using light-emitting diodes, liquid crystals, or 
other electro illuminating devices where one or 
more than one type of information or message may 
be displayed. 

55. Requirements, ((a) Except as provided in 
paragraph (b) of this section, each passenger car, 
multipurpose passenger vehicle, truck, and bus 
manufactured with any control listed in S5.1 or in 
column 1 of Table 1, and each passenger car, 
multipurpose passenger vehicle and truck or bus 
less than 10,000 pounds GVWR with any display 
hsted in S5.1 or in column 1 of Table 2, shall meet 
the requirements of this standard for the location, 
identification, and illumination of such control or 
display. 

(b) For vehicles manufactured before September 
1, 1987, a manufacturer may, at its option— 



(1) Meet the requirements in this standard to 
use identifying words or abbreviation or identify- 
ing symbol for a control by using those specified 
in Table 1(a) instead of Table 1. If none are 
specified in Table 1(a), none need be used for the 
control. 

(2) Meet the requirements in this standard to 
use identifying words or abbreviation or identify- 
ing symbol for a display by using those specified 
in Table 2(a) instead of Table 2. If none are 
specified in Table 2(a), none need by used for the 
display. (49 F.R. 30191-July 27, 1984. Effec- 
tive: July 27, 1984)1 

S5.1 Location. Under the conditions of S6, 
each of the following controls that is furnished 
shall be operable by the driver and each of the 
following displays that is furnished shall be visi- 
ble to the driver. Under conditions of S6, 
telltales and informational readout displays are 
considered visible when activated. 

Hand-Operated Controls 

(a) Steering wheel. 

(b) Horn. 

(c) Ignition. 

(d) Headlamp. 

(e) Tail lamp. 

(f) Turn signal. 

(g) Illumination intensity, 
(h) Windshield wiper. 

(i) Windshield washer. 

(j) Manual transmission shift lever, except 
transfer case. 

(k) Windshield defrosting, and defogging 
system. 

(1) Rear window defrosting and defogging 
system. 

(m) Manual choke. 

(n) Driver's sun visor. 



(Rev. 7/27/84) 



PART 571; S 101-1 



(0) 

(p) 

(q) 



Automatic vehicle speed system. 

Highbeam. 

Hazard warning signal, 
(r) Clearance lamps, 
(s) Hand throttle, 
(t) Identification lamps. 

Foot-Operated Controls 

(a) Service brake. 

(b) Accelerator. 

(c) Clutch. 

(d) Highbeam. 

(e) Windshield washer. 

(f) Windshield wiper. 

Displays 

(a) Speedometer. 

(b) Turn signal. 

(c) Gear position. 

(d) Brake failure warning. 

(e) Fuel. 

(f) Engine coolant temperature. 

(g) Oil. 

(h) Highbeam. 
(i) Electrical Charge. 
S5.2 Identification. 

S5.2.1 Vehicle controls shall be identified as 
follows: 

[(a) Except as specified in S5.2.1(b), any hand- 
operated control listed in column 1 of Table 1 that 
has a symbol designated in column 3 shall be iden- 
tified by that symbol. Any such control for which 
no symbol is shown in Table 1 shall be identified by 
the word or abbreviation shown in column 2, if 
such word or abbreviation is shown. Words or sym- 
bols in addition to the required symbol, word or ab- 
breviation may be used at the manufacturer's 
discretion for the purpose of clarity. Any such con- 
trol for which column 2 of Table 1 and/ or column 3 
of Table 1 specifies "Mfr. Option" shall be iden- 
tified by the manufacturer's choice of a symbol, 
word or abbreviation, as indicated by that 
specification in column 2 and/ or column 3. The 
identification shall be placed on or adjacent to the 
control. The identification shall, under the condi- 
tions of S6, be visible to the driver and, except as 
provided in S5.2.1.1 and S5.2.1.2, appear to the 
driver perceptually upright. (49 F.R. 30191— July 
27, 1984. Effective: July 27, 1984)1 

(b) S5.2.1(a) does not apply to a turn signal con- 
trol which is operated in a plane essentially parallel 
to the face plane of the steering wheel in its normal 
driving position and which is located on the left 



side of the steering column so that it is the control 
on that side of the column nearest to the steering 
wheel face plane. 

55.2.1.1 [The identification of a master lighting 
switch or headlamp and tail lamp control that ad- 
justs control and display illumination by means of 
rotation, or of any other rotating control that does 
not have an off position, need not appear to the 
driver perceptually upright. The identification of a 
horn control need not appear to the driver percep- 
tually upright except when the vehicle, aligned to 
the manufacturer's specifications, has its wheels 
positioned for the vehicle to travel in a straight for- 
ward direction. (49 F.R. 30191-July 27, 1984. Ef- 
fective: July 27, 1984)1 

55.2.1 .2 The identification of a rotating control 
other than one described by S5.2.1.1 shall appear 
to the driver perceptually upright when the control 
is in the off position. 

S.5.2.2 Identification shall be provided for each 
function of any automatic vehicle speed system 
control and any heating and air conditioning 
system control, and for the extreme positions of 
any such control that regulates a function over a 
quantitative range. If this identification is not 
specified in Tables 1 or 2, it shall be in word [or 
symbol] form unless color coding is used. If color 
coding is used to identify the extreme positions of a 
temperature control, the hot extreme shall be iden- 
tified by the color red and the cold extreme by the 
color blue. 

Example 1 A slide lever controls the 
temperature of the air in the vehicle heating 
system over a continuous range, from no heat 
to maximum heat. Since the control regulates a 
single function over a quantitative range, only 
the extreme positions require identification. 

Example 2 A switch has three positions, for 
heat, defrost, and air conditioning. Since each 
position regulates a different function, each 
position must be identified. 

S5.2.3 Except for informational readout 
displays, any display located within the passenger 
compartment and listed in column 1 of Table 2 that 
has a symbol designated in column 4, shall be iden- 
tified by that symbol. Such display may, in addition 
be identified by the word or abbreviation shown in 
column 3. Any such display for which no symbol is 
provided in Table 2 shall be identified by the word 
or abbreviation shown in column 3. Informational 
readout displays may be identified by the symbol 



(Rev. 7/27/84) 



PART 571; S 101-2 



FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 101 



Controls and Displays 

(Docket No. 1-18; Notice 13) 



51. Scope. This standard specifies require- 
ments for the location, identification, and illumina- 
tion of motor vehicle controls and displays. 

52. Purpose. The purpose of this standard is to 
ensure the accessibility and visibility of motor vehi- 
cle controls and displays and to facilitate their 
selection under daylight and nighttime conditions, 
in order to reduce the safety hazards caused by the 
diversion of the driver's attention from the driving 
task, and by mistakes in selecting controls. 

53. Application. This standard applies to 
passenger cars, multipurpose passenger vehicles, 
trucks, and buses. 

54. Definitions. 

"Telltale" means a display that indicates, by 
means of a light-emitting signal, the actuation of a 
device, a correct or defective functioning or condi- 
tion, or a failure to function. 

"Gauge" means a display that is listed in S5.1 or 
in Table 2 and is not a telltale. 

"Informational readout display" means a display 
using light-emitting diodes, liquid crystals, or 
other electro illuminating devices where one or 
more than one type of information or message may 
be displayed. 

55. Requirements, [(a) Except as provided in 
paragraph (b) of this section, each passenger car, 
multipurpose passenger vehicle, truck, and bus 
manufactured with any control listed in S5.1 or in 
column 1 of Table 1, and each passenger car, 
multipurpose passenger vehicle and truck or bus 
less than 10,000 pounds GVWR with any display 
listed in S5.1 or in column 1 of Table 2, shall meet 
the requirements of this standard for the location, 
identification, and illumination of such control or 
display. 

(b) For vehicles manufactured before September 
1, 1987, a manufacturer may, at its option— 



(1) Meet the requirements in this standard to 
use identifying words or abbreviation or identify- 
ing symbol for a control by using those specified 
in Table 1(a) instead of Table 1. If none are 
specified in Table 1(a), none need be used for the 
control. 

(2) Meet the requirements in this standard to 
use identifying words or abbreviation or identify- 
ing symbol for a display by using those specified 
in Table 2(a) instead of Table 2. If none are 
specified in Table 2(a), none need by used for the 
display. (49 F.R. 30191-July 27, 1984. Effec- 
tive: July 27, 1984)1 

S5.1 Location. Under the conditions of S6, 
each of the following controls that is furnished 
shall be operable by the driver and each of the 
following displays that is furnished shall be visi- 
ble to the driver. Under conditions of S6, 
telltales and informational readout displays are 
considered visible when activated. 

Hand-Operated Controls 

(a) Steering wheel. 

(b) Horn. 

(c) Ignition. 

(d) Headlamp. 

(e) Tail lamp. 

(f) Turn signal. 

(g) Illumination intensity, 
(h) Windshield wiper. 

(i) Windshield washer. 

(j) Manual transmission shift lever, except 
transfer case. 

(k) Windshield defrosting, and defogging 
system. 

(1) Rear window defrosting and defogging 
system. 

(m) Manual choke. 

(n) Driver's sun visor. 



(Rev. 7/27/84) 



PART 571; S 101-1 



(o) Automatic vehicle speed system. 

(p) Highbeam. 

(q) Hazard warning signal. 

(r) Clearance lamps. 

(s) Hand throttle. 

(t) Identification lamps. 

Foot-Operated Controls 

(a) Service brake. 

(b) Accelerator. 

(c) Clutch. 

(d) Highbeam. 

(e) Windshield washer. 

(f ) Windshield wiper. 

Displays 

(a) Speedometer. 

(b) Turn signal. 

(c) Gear position. 

(d) Brake failure warning. 

(e) Fuel. 

(f) Engine coolant temperature. 

(g) Oil. 

(h) Highbeam. 
(i) Electrical Charge. 
S5.2 Identification. 

S5.2.1 Vehicle controls shall be identified as 
follows: 

1(a) Except as specified in S5.2.1(b), any hand- 
operated control listed in column 1 of Table 1 that 
has a symbol designated in column 3 shall be iden- 
tified by that symbol. Any such control for which 
no symbol is shown in Table 1 shall be identified by 
the word or abbreviation shown in column 2, if 
such word or abbreviation is shown. Words or sym- 
bols in addition to the required symbol, word or ab- 
breviation may be used at the manufacturer's 
discretion for the purpose of clarity. Any such con- 
trol for which column 2 of Table 1 and/ or column 3 
of Table 1 specifies "Mfr. Option" shall be iden- 
tified by the manufacturer's choice of a symbol, 
word or abbreviation, as indicated by that 
specification in column 2 and/ or column 3. The 
identification shall be placed on or adjacent to the 
control. The identification shall, under the condi- 
tions of S6, be visible to the driver and, except as 
provided in S5.2.1.1 and S5.2.1.2, appear to the 
driver perceptually upright. (49 F.R. 30191— July 
27, 1984. Effective: July 27, 1984)1 

(b) S5.2.1(a) does not apply to a turn signal con- 
trol which is operated in a plane essentially parallel 
to the face plane of the steering wheel in its normal 
driving position and which is located on the left 



side of the steering column so that it is the control 
on that side of the column nearest to the steering 
wheel face plane. 

55.2.1 .1 [The identification of a master lighting 
switch or headlamp and tail lamp control that ad- 
justs control and display illumination by means of 
rotation, or of any other rotating control that does 
not have an off position, need not appear to the 
driver perceptually upright. The identification of a 
horn control need not appear to the driver percep- 
tually upright except when the vehicle, aligned to 
the manufacturer's specifications, has its wheels 
positioned for the vehicle to travel in a straight for- 
ward direction. (49 F.R. 30191 -July 27, 1984. Ef- 
fective: July 27, 1984)1 

55.2.1 .2 The identification of a rotating control 
other than one described by S5.2.1.1 shall appear 
to the driver perceptually upright when the control 
is in the off position. 

S.5.2.2 Identification shall be provided for each 
function of any automatic vehicle speed system 
control and any heating and air conditioning 
system control, and for the extreme positions of 
any such control that regulates a function over a 
quantitative range. If this identification is not 
specified in Tables 1 or 2, it shall be in word [or 
symboll form unless color coding is used. If color 
coding is used to identify the extreme positions of a 
temperature control, the hot extreme shall be iden- 
tified by the color red and the cold extreme by the 
color blue. 

Example 1 A slide lever controls the 
temperature of the air in the vehicle heating 
system over a continuous range, from no heat 
to maximum heat. Since the control regulates a 
single function over a quantitative range, only 
the extreme positions require identification. 

Example 2 A switch has three positions, for 
heat, defrost, and air conditioning. Since each 
position regulates a different function, each 
position must be identified. 

S5.2.3 Except for informational readout 
displays, any display located within the passenger 
compartment and listed in column 1 of Table 2 that 
has a symbol designated in column 4, shall be iden- 
tified by that symbol. Such display may, in addition 
be identified by the word or abbreviation shown in 
column 3. Any such display for which no symbol is 
provided in Table 2 shall be identified by the word 
or abbreviation shown in column 3. Informational 
readout displays may be identified by the symbol 



(Rev. 7/27/84) 



PART 571; S 101-2 



designated in column 4 of Table 2 or by the word or 
abbreviation shown in column 3. Additional words 
or symbols may be used at the manufacturer's dis- 
cretion for the purpose of clarity. The identifica- 
tion required or permitted by this section shall be 
placed on or adjacent to the display that it iden- 
tifies. The identification of any display shall, under 
the conditions of S6, be visible to the driver and 
appear to the driver perceptually upright. 
S5.3 Illumination. 

55.3.1 Except for foot-operated controls or 
hand-operated controls mounted upon the floor, 
floor console, or steering column, or in the wind- 
shield header area, the identification required by 
§ 5.2.1 or § 5.2.2 of any control listed in column 1 
of Table 1 and accompanied by the word "yes" in 
the corresponding space in column 4 shall be 
capable of being illuminated whenever the 
headlights are activated. However, control iden- 
tification for a heating and air-conditioning system 
need not be illuminated if the system does not 
direct air directly upon windshield. If a gauge is 
listed in column 1 of Table 2 and accompanied by 
the word "yes" in column 5, then the gauge and its 
identification required by § 5.2.3 shall be 
illuminated whenever the ignition switch and /or 
the headlamps are activated. Controls, gauges, and 
their identifications need not be illuminated when 
the headlamps are being flashed. A telltale shall 
not emit light except when identifying the mal- 
function or vehicle condition for whose indication it 
is designed or during a bulb check upon vehicle 
starting. 

55.3.2 Except for informational readout 
displays, each discrete and distinct telltale shall be 
of the color shown in column 2 of Table 2. The iden- 



tification of each telltale shall be in a color that con- 
trasts with the lens, if a telltale with a lens is used. 
Any telltale used in conjunction with a gauge need 
not be identified. The color of informational 
readout displays will be at the option of the 
manufacturer. 

S5.3.3 Light intensities for controls, gauges, 
and their identification shall be continuously 
variable from: (a) a position at which either there is 
no light emitted or the light is barely discernible to 
a driver who has adapted to dark ambient roadway 
conditions to (b) a position providing illumination 
sufficient for the driver to identify the control or 
display readily under conditions of reduced visi- 
bility. Light intensities for informational readout 
systems shall have at least two values, a higher one 
for day, and a lower one for nighttime that is pro- 
vided in the passenger compartment when and 
only when the headlights are activated shall also be 
variable in a manner that complies with this 
paragraph. The light intensity of each telltale shall 
not be variable and shall be such that, when ac- 
tivated, that telltale and its identification are visi- 
ble to the driver under all daytime and nighttime 
conditions. 

S6. Conditions. The driver is restrained by the 
crash protection equipment installed in accord- 
ance with the requirements of § 57L208 of this 
part (Standard No. 208), adjusted in accordance 
with the manufacturer's instructions. 

Joan Claybrook 
Administrator 

43 F.R. 27541 
June 26, 1978 



PART 571; S 101-3-4 



e 



designated in column 4 of Table 2 or by the word or 
abbreviation shown in column 3. Additional words 
or symbols may be used at the manufacturer's dis- 
cretion for the purpose of clarity. The identifica- 
tion required or permitted by this section shall be 
placed on or adjacent to the display that it iden- 
tifies. The identification of any display shall, under 
the conditions of S6, be visible to the driver and 
appear to the driver perceptually upright. 
S5.3 Illumination. 

55.3.1 Except for foot-operated controls or 
hand-operated controls mounted upon the floor, 
floor console, or steering column, or in the wind- 
shield header area, the identification required by 
§ 5.2.1 or § 5.2.2 of any control listed in column 1 
of Table 1 and accompanied by the word "y^s" in 
the corresponding space in column 4 shall be 
capable of being illuminated whenever the 
headlights are activated. However, control iden- 
tification for a heating and air-conditioning system 
need not be illuminated if the system does not 
direct air directly upon windshield. If a gauge is 
listed in column 1 of Table 2 and accompanied by 
the word "yes" in column 5, then the gauge and its 
identification required by § 5.2.3 shall be 
illuminated whenever the ignition switch and /or 
the headlamps are activated. Controls, gauges, and 
their identifications need not be illuminated when 
the headlamps are being flashed. A telltale shall 
not emit light except when identifying the mal- 
function or vehicle condition for whose indication it 
is designed or during a bulb check upon vehicle 
starting. 

55.3.2 Except for informational readout 
displays, each discrete and distinct telltale shall be 
of the color shown in column 2 of Table 2. The iden- 



tification of each telltale shall be in a color that con- 
trasts with the lens, if a telltale with a lens is used. 
Any telltale used in conjunction with a gauge need 
not be identified. The color of informational 
readout displays will be at the option of the 
manufacturer. 

S5.3.3 Light intensities for controls, gauges, 
and their identification shall be continuously 
variable from: (a) a position at which either there is 
no light emitted or the light is barely discernible to 
a driver who has adapted to dark ambient roadway 
conditions to (b) a position providing illumination 
sufficient for the driver to identify the control or 
display readily under conditions of reduced visi- 
bility. Light intensities for informational readout 
systems shall have at least two values, a higher one 
for day, and a lower one for nighttime that is pro- 
vided in the passenger compartment when and 
only when the headlights are activated shall also be 
variable in a manner that complies with this 
paragraph. The light intensity of each telltale shall 
not be variable and shall be such that, when ac- 
tivated, that telltale and its identification are visi- 
ble to the driver under all daytime and nighttime 
conditions. 

S6. Conditions. The driver is restrained by the 
crash protection equipment installed in accord- 
ance with the requirements of § 57L208 of this 
part (Standard No. 208), adjusted in accordance 
with the manufacturer's instructions. 

Joan Claybrook 
Administrator 

43 F.R. 27541 
June 26, 1978 



PART 571; S 101-3-4 



TABLE 1 
Identification and Illumination of Controls 



Column 1 


Column 2 


Column 3 


Column 4 


Hand Operated Controls 


Identifying Words 
or Abbreviation 


Identifying 
Symbol 


Illumination 


Master Lighting 
Switch 




-n-- 








Headlamps and 
Tail lamps 


(Mfr Option)' 


(Mfr Option)' 






Horn 




kr ' 








Turn Signal 




0*; 








Hazard Warning 
Signal 




A^ 


Yes 




Windshield Wiping 
System 




V 


Yes 




Windshield Washing 
System 




.P^ 

^ 


Yes 




Windshield Washing 
and Wiping Combined 






Yes 




Heating and or Air 
Conditioning Fan 




:t.% 


Yhs 




Windshield Defrosting 
and Defogging System 




^ 


Yes 




Rear Window Defrosting 
and Defogging System 






Yes 


M- 




) J) 


Identification, Side 

Marker and or Clearance 

Lamps 






Yes 




Manual Choke 


Choke 










Engine Start 


Engine Start' 










Engine Stop 


Engine Stop' 




Yes 




Hand Throttle 


Throttle 










Automatic Vehicle Speed 


(Mfr OptionI 




Yes 




Heating and Air 

Conditioning 

System 


(Mfr OptionI 


(Mfr Option) 


Yes 



' Use when engine control is separate from the key locking system, 
' Separate identification not required if controlled by master lighting switch. 

^ The pair of arrows is a single symbol When the controls for left and right turn operate independently, 
however, the two arrows maybe considered separate symbols and be spaced accordingly 

* Identification not required for vehicles with a GVWR greater the 10.000 lbs , or for narrow ring-type controls 

* Framed areas may be filled. 



PART 571; S 101-5 



TABLE 1A 
Identification and Illumination of Controls 



Column 1 


Column 2 


Column 3 


Column 4 


Hand Operated Controls 


Identifying Words or Abbreviation 


Identifying Symbol 


Illumination 


Headlamps and 
Tail Lamps 


Lights 


^r>. 2 4 




Turn Signal 




oo 




Hazard Warning 
Signal 


Hazard 


A ' 


Yes 


Clearance Lamps 
System 


Clearance Lamps or CI Lps 


-:cd:- ' ' 


Yes 


Windshield Wiping 
System 


Wiper or Wipe 


V 


Yes 


Windshield Washing 
System 


Washer or Wash 


^ 


Yes 


Windshield Washing and 
Wiping Combined 


Wash-Wipe 


^ 


Yes 


Heating and/or Air 
Conditioning Fan 


Fan 


§g 


Yes 


Windshield Defrosting & 
Defogging System 


Defrost, Defog or Def 


w 


Yes 


Rear Window Defrosting 
and Defogging System 


Rear Defrost, Rear Defog 
or Rear Def 




Yes 


^ 


nil 


Engine Start 


Engine Start' 






Engine Stop 


Engine Stop' 




Yes 


Manual Choke 


Choke 






Hand Throttle 


Throttle 






Automatic Vehicle Speed 


(Mfg Option) 




Yes 


Identification Lamps 


Identification Lamps or Lps 




Yes 


Heating and Air 
Conditioning System 


(Mfg Option) 




Yes 



1. Use when engine control is separate from the key locking system. 

2. Use also when clearance, identification, parking and/or side marker lamps are controlled with the 
headlamp switch. 

3. Use also when clearance lamps, identification lamps and/or side marker are controlled with one 
switch other than the headlamp switch. 

4. Framed areas may be filled. 



(Rev. 7/27«84) 



PART 571; S 101-6 



TABLE 1 
Identification and Illumination of Controls 



Column 1 


Column 2 


Column 3 


Column 4 


Hand Operated Controls 


Identifying Words 
or Abbreviation 


Identifying 
Symbol 


Illumination 


Master Lighting 
Switch 




-Py 








Headlamps and 
Tail lamps 


iMfr Optionl^ 


(Mfr, Option)' 






Horn 




kr ' 








Turn Signal 




<i"!> ] 








Hazard Warning 
Signal 




A 


Yes 




Windshield Wiping 
System 




V 


Yes 




Windshield Washing 
System 




a 


Yes 




Windshield Washing 
and Wiping Combined 




«« «% 

^ 


Yes 




Heating and or Air 
Conditioning Fan 




9i..^88 


Yes 




Windshield Defrosting 
and Defogging System 




^ 


Yes 




Rear Window Defrosting 
and Defogging System 






Yes 


M- 




))) 


Identification, Side 

Marker and or Clearance 

Lamps 




-00- 


Yes 




Manual Choke 


Choke 










Engine Start 


Engine Start' 










Engine Stop 


Engine Stop' 




Yes 




Hand Throttle 


Throttle 










Automatic Vehicle Speed 


(Mfr Option) 




Yes 




Heating and Air 

Conditioning 

System 


(Mfr, Option) 


iMfr Option) 


Yes 

... 



' Use when engine control is separate from the key locking system 
' Separate identification not required if controlled by master lighting switch 

' The pair of arrows is a single symbol. When the controls for left and right turn operate independently, 
however, the two arrows may be considered separate symbols and be spaced accordingly 

* Identification not required for vehicles with a GVWR greater the 10,000 lbs . or for narrow ring-type controls 
' Framed areas may be filled 

PART 571; S 101-5 



TABLE 1A 
Identification and Illumination of Controls 



Column 1 


Column 2 


Column 3 


Column 4 


Hand Operated Controls 


Identifying Words or Abbreviation 


Identifying Symbol 


Illumination 










Headlamps and 
Tail Lamps 


Lights 


ID ' 




Turn Signal 




<><> 




Hazard Warning 
Signal 


Hazard 


A ' 


Yes 


Clearance Lamps 
System 


Clearance Lamps or CI Lps 


-:aDc ' ^ 


Yes 


Windshield Wiping 
System 


Wiper or Wipe 


V 


Yes 


Windshield Washing 
System 


Washer or Wash 


^ 


Yes 


Windshield Washing and 
Wiping Combined 


Wash-Wipe 


^ 


Yes 


Heating and/or Air 
Conditioning Fan 


Fan 


m 


Yes 


Windshield Defrosting & 
Defogging System 


Defrost, Defog or Def 


<w 


Yes 


Rear Window Defrosting 
and Defogging System 


Rear Defrost, Rear Defog 
or Rear Def 




Yes 


C¥ 


))) 


Engine Start 


Engine Start' 






Engine Stop 


Engine Stop' 




Yes 


Manual Choke 


Choke 






Hand Throttle 


Throttle 






Automatic Vehicle Speed 


(Mfg Option) 




Yes 


Identification Lamps 


Identification Lamps or Lps 




Yes 


Heating and Air 
Conditioning System 


(Mfg Option) 




Yes 



1. Use when engine control is separate from the key locking system. 

2. Use also when clearance, identification, parking and/or side marker lamps are controlled with the 
headlamp switch. 

3. Use also when clearance lamps, identification lamps and/or side marker are controlled with one 
switch other than the headlamp switch. 

4. Framed areas may be filled. 



(Rev. 7/27/84) 



PART 571; S 101-6 



TABLE 2 
Identification and Illumination of Displays 



Column 1 


Column 2 


Column 3 


Column 4 


Column b 


Display 


Telltale 
Color 


Identifying Words 
or Abbreviation 


Identifying 
Symbol 


Illumination 


Turn Signal 
Telltale 


Green 


Also see 
FMVSS 108 


<^'=i>: 




Hazard Warning 
Telltale 


Red' 


Also see 
FMVSS 108 


a: 




Seat 
Belt 

Telltale 


Red" 


Also see 
FMVSS 208 


'Tr - ^^ 






Fuel Level 
Telltale 


Yellow 


Fuel 


»,B 




Yes 


Gauge 






Oil Pressure 
Telltale 


Red" 


Oil 


*&r. 




Yes 


Gauge 






Coolant Temperature 
Telltale 


Red" 


Temp 


-,K 


Yes 


Gauge 






Electrical Charge 
Telltale 


Red" 


Volts, Charge 
or Amp 


n\ 




Yes 


Gauge 








Highbeam 
Telltale 


Blue or 
Green" 


Also see 
FMVSS 108 


ID" 




Malfunction in 
Anti-Lock or 


Yellow 


Antilock or Anti lock 
Also see FMVSS 105 








Brake System 


Red" 


Brake. Also 
see FMVSS 105 










Brake Air Pressure 
Position Telltale 


Red" 


Brake Air Also 
see FMVSS 121 








Speedometer 




MPH* 




Yes 




Odometer 




. 3 










Automatic Gear 
Position 




Also see 
FMVSS 102 




Yes 







' The pair of arrows Is a single symbol. When the indicator for left and right turn operate independently, however, the two arrows 

will be considered separate symbols and may be spaced accordingly 
^ Not required when arrows of turn signal tell -tales that otherwise operate independently flash simultaneously as hazard warning 

tell-tale. 

If the odometer indicates kilometers, then "KILOMETERS" or "km" shall appear, otherwise, no identification is required. 

Red can be red-orange Blue can be blue-green 
^ If the speedometer is graduated in miles per hour and in kilometers per hour, the identifying words or abbreviations shall be 

"MPH and km h" in any combination of upper or lower case letters 

Framed areas may be filled. 



PART 571; S 101-7 



TABLE 2A 
Identification and Illumination of Internal Displays 



Column 1 


Column 2 


Column 3 


Column 4 


Column 5 


Display 


Tell-Tale 
Color 


Identifying Words or 
Abbreviation 


Identifying Symbol 


Illuminate 


Turn Signal 
Tell-Tale 


Green 


Also see 
FMVSS 108 


<p<> : 




Hazard Warning 
Tell-Tale 


Red^ 


Also see 
FMVSS 108 


A : 




Seat Bell 
Tell-Tale 


Red-* 


Also see 
FMVSS 208 


-i 


— 


Fuel Level, Tell-Tale 


Yellow 


Fuel 


ffi 




Gauge 




Fuel 


Yes 


Oil Pressure 
Tell-Tale 


Red4 


Oil 


'^^i 




Gauge 




Oil 


Yes 


Coolant Temperature 
Tell-Tale 


Red-* 


Temp 


-t 




Gauge 




Temp 


Yes 


Electrical Charge 
Tell-Tale 


Red-* 


Volts, Charge or Amp 







1- * 


Gauge 




Volts, Charge or Amp 


Yes 




Speedometer 




MPH« 




Yes 


Odometer 




T, 






Automatic Gear 
Position 




Also see 
FMVSS 102 




Yes 


High Beam 
Tell-Tale 


Blue or 
(ireen'' 


Also see 
FMVSS 108 


iO . 




Brake Air Pressure 
Position, Tell-Tale 


Red-* 


Brake Air Also see 
FMVSS 121 






Malfunction in 
Anti-Lock or 


Yellow 


Anti-Lock Also see 
FMVSS 105-75 






Brake System 


Red-* 


Brake Also see 
FMVSS 105-75 







1. The pair of arrows is a single symbol. When the indicator for left and right turn operate independently, 
however, the two arrows will be considered separate symbols and may be spaced accordingly. 

2. Not required when arrows of turn signal tell-tales that otherwise operate independently flash simul- 
taneously as hazard warning tell-tale. 

3. If the odometer indicates kilometers, then "KILOMETERS" or "km" shall appear otherwise, no 
identification is required. 

4. Red can be red-orange. Blue can be blue-green. 

5. Framed areas may be filled. 

6. If the speedometer is graduated in miles per hour and in kilometers per hour, the identifying words or 
abbreviations shall be "MPH and km/h" in any combination of upper or lower case letters. 



(Rev. 7/27/84) 



PART 571; S 101-8 



TABLE 2 
Identification and Illumination of Displays 



Column 1 


Column 2 


Column 3 


Column 4 


Column 5 


Display 


Telltale 
Color 


Identifying Words 
or Abbreviation 


Identifying 
Symbol 


Illumination 


Turn Signal 
Telltale 


Green 


Also see 
FMVSS 108 


<p'^: 






Hazard Warning 
Telltale 


Red-* 


Also see 
FMVSS 108 


a; 






Seat 

Belt 

Telltale 


Red^ 


Also see 
FMVSS 208 


^\r ■•• -Tz^ 






Fuel Level 
Telltale 


Yellow 


Fuel 


».ffi 




Yes 


Gauge 






Oil Pressure 
Telltale 


Red" 


Oil 


*fe^ 




Yes 


Gauge 






Coolant Temperature 
Telltale 


Red" 


Temp 


-R- 




Yes 


Gauge 






Electrical Charge 
Telltale 


Red" 


Volts, Charge 
or Amp 


n\ 




Yes 


Gauge 








Highbeam 
Telltale 


Blue or 
Green 


Also see 
FMVSS 108 


ID" 






Malfunction in 
Anti-Lock or 


Yellow 


Antilock or Anti lock 
Also see FMVSS 105 








Brake System 


Red" 


Brake. Also 
see FMVSS 105 










Brake Air Pressure 
Position Telltale 


Red" 


Brake Air Also 
see FfVIVSS 121 








Speedometer 




mph"" 




Yes 






3 










Automatic Gear 
Position 




Also see 
FMVSS 102 




Yes 







The pair of arrows is a single symbol When the indicator for left and right turn operate independently, however, the two arrows 
will be considered separate symbols and may be spaced accordingly 

Not required when arrows of turn signal tell-tales that otherwise operate independently flash simultaneously as hazard warning 

tell-tale. 

If the odometer indicates kilometers, then "KILOMETERS" or "km" shall appear, otherwise, no identification is required. 

Red can be red orange Blue can be blue green. 

If the speedometer is graduated in miles per hour and in kilometers per hour, the identifying words or abbreviations shall be 

"MPH and km h" in any combination of upper or lower case letters 

Framed areas may be filled. 



PART 571; S 101-7 



TABLE 2A 
Identification and Illumination of Internal Displays 



Column I 


Column 2 


Column 3 


Column 4 


Column 5 


Display 


Tell-Tale 
Color 


Identifying Words or 
Abbreviation 


Identifying Symbol 


Illuminate 


Turn Signal 
Tell-Tale 


Green 


Also see 
FMVSS 108 


oo ; 




Hazard Warning 
Tell-Tale 


Red-* 


Also see 
FMVSS 108 


A : 




Seat Bell 
Tell-Tale 


Red-* 


Also see 
FMVSS 208 


4 




Fuel Level, Tell-Tale 


Yellow 


Fuel 


B 




Gauge 




Fuel 


Yes 


Oil Pressure 
Tell-Tale 


Red'* 


Oil 


'r^i 




Gauge 




Oil 


Yes 


Coolant Temperature 
Tell-Tale 


Red-* 


Temp 


X 




Gauge 




Temp 


Yes 


Electrical Charge 
Tell-Tale 


Red-* 


Volts, Charge or Amp 






£3 


Gauge 




Volts, Charge or Amp 


Yes 




Speedometer 




MPH<^ 




Yes 


Odometer 




, 1 






Automatic Gear 
Position 




Also see 
FMVSS 102 




Yes 


High Beam 
Tell-Tale 


Blue or 
(Ireen* 


Also see 
FMVSS 108 


iO . 




Brake Air Pressure 
Position, Tell-Tale 


Red-* 


Brake Air Also see 
FMVSS 121 






Malfunction in 
Ami-Lock or 


Yellow 


Anti-Lock Also see 
FMVSS 105-75 






Brake System 


Red-* 


Brake Also see 
FMVSS 105-75 







1 . The pair of arrows is a single symbol. Wlien the indicator for left and right turn operate independently, 
however, the two arrows will be considered separate symbols and may be spaced accordmgly. 

2. Not required when arrows of turn signal tell-tales that otherwise operate independently flash simul- 
taneously as hazard warning tell-tale. 

3. If the odometer indicates kilometers, then -'KILOMETERS" or "km" shall appear otherwise, no 
identification is required. 

4. Red can be red-orange. Blue can be blue-green. 

5. Framed areas may be filled. 

6. If the speedometer is graduated in miles per hour and in kilometers per hour, the identifying words or 
abbreviations shall be "MPH and km/h" in any combination of upper or lower case letters. 



(Rev. 7/27/84) 



PART 571; S 101-8 



i 



PREAMBLE TO FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 101-80 



Controls and Displays 
(Docket No. 1-18; Notice 13) 



Action: Final rule. 



Summary: This notice expands the applica- 
tion of the standard for the location, identifica- 
tion, and illumination of driver controls and 
displays (e.g., gauges and meters) by establishing 
requirements for additional controls and by in- 
troducing selected displays which, if furnished, 
must be located and illuminated under specified 
conditions and identified by a specified symbol 
and/or selected word. The purpose of the re- 
quirements is to encourage international stand- 
ardization and harmonization of controls and 
displays in order to convey information more 
quickly to drivers and with less chance of human 
error. This will reduce the interval during which 
a driver's attention is diverted from the roadway 
to his controls and displays, thus decreasing the 
possibility of an accident. 

Effective date: September 1, 1980. 

For further information contact : 

Mr. Nelson Erickson, Office of Motor Vehicle 
Programs, 400 Seventh Street, S.W., "Wash- 
ington, D.C. 20590, 202-426-2155. 

Supplementary information: This notice estab- 
lishes new requirements for the location, identifi- 
cation, and illumination of controls and displays 
in passenger cars, multipurpose passenger ve- 
hicles, trucks, and buses. The new rule is desig- 
nated 49 CFR 571.101-80, Controls and Displays, 
and becomes effective September 1, 1980. The 
existing rule on this subject, 49 CFR 571.101, 
Control Location, /dentif cation, and Illumina- 
tion, is amended to permit, at the vehicle 
manufacturer's option, compliance with that 
standard or the new requirements of Standard 
No. 101-80 before September 1, 1981. 



On October 21, 1976, the National Highway 
Traffic Safety Administration published (41 FR 
46460) a notice proposing to update the existing 
controls and displays standard (Standard 101) 
by incorporating all pertinent amendments and 
interpretations published since the original issu- 
ance on January 31, 1967. It also proposed to 
consolidate the control and display requirements 
of other standards in one regulation. This notice 
takes final action on that proposal. All com- 
ments were considered and the major ones are 
discussed below. 

The notice issued in October 1976 proposed 
that most controls and displays be required to 
be identified with specified symbols which are 
internationally standardized. Words would have 
been permitted in addition to the symbols, 
although the choice of words would have been 
limited to ensure uniformity. Specified words 
would have been required for those controls and 
displays for which no symbols had been estab- 
lished. 

The rationale behind the proposed requirement 
of symbols was that they can convey information 
more quickly and with less chance of human 
error than words. This is particularly true with 
respect to the large foreign language speaking 
population of this country. By simplifying the 
identification of controls and displays, the stand- 
ard should reduce the problems resulting from 
driver's attention being diverted from the road- 
way to his controls and displays. An individual 
benefit cited in the proposed notice is that manu- 
facturers who sell vehicles both in and outside 
of the United States could realize significant 
cost savings by utili2nng internationally stand- 
ardized symbols. 



PART 571; S 101-80— PRE 1 



The National Motor Vehicle Advisory Council 
and the Vehicle Equipment Safety Commission 
did not take positions on the proposal. The ma- 
jority of commenters favored the use of symbols 
in the interest of international standardization 
and harmonization. The final rule, therefore, re- 
quires the use of symbols and allows the use of 
additional words if the manufacturer so chooses. 

One of the major concerns of manufacturers 
commenting was that the proposed rule would 
inhibit the design and development of electronic 
"readout" panels which can effectively present 
to the driver specific information concerning ve- 
hicle and environmental conditions affecting 
safety. These displays are currently capable of 
exhibiting information and warnings with word 
messages and not with symbols. The optional 
use of symbols or words will permit the con- 
tinued development of informational readout 
displays. The NHTSA supports the develop- 
ment of more efiicient and effective control and 
display information systems and has, conse- 
quently, permitted informational readout dis- 
plays to be identified by words only so as to not 
impede the development of electronic displays. 

The symbols that are permitted by this rule 
to identify controls and displays are those de- 
veloped by the International Standards Organi- 
zation (ISO). By specifying symbols adopted 
by the ISO, this agency is facilitating the 
achieveinent of an international uniform identifi- 
cation system. New symbols for five controls 
and eight displays are added to those presently 
designated in the existing standard. Additional 
symbols will be added when the NHTSA deter- 
mines which ones will be readily recognizable, 
thus reducing driver diversion. 

Some commenters noted that a few of the 
symbols such as the clearance lamp symbol, de- 
viate slightly from those adopted by the ISO. 
The NHTSA, while basing its symbols on those 
developed by the ISO, is not specifying ISO 
symbols which it determines will not adequately 
convey the intended message. Thus, the symbols 
proposed in the October notice are adopted, 
even though some of them deviate from the ISO 
symbols. Some existing ISO symbols are not 
included in this final rule due to the fact that 
additional data are needed on their recogniza- 
bility. When such data have been accumulated 



and analyzed, the NHTSA will determine 
whether the symbols should be added to Stand- 
ard 101-80. 

A few commenters suggested the deletion of 
the symbols for the turn signal and high beam 
telltales because these have long been identified 
by color and operate only after deliberate opera- 
tion by the driver. It is the belief of the 
NHTSA that these symbols should be retained. 
They are necessary to educate new drivers, to 
act as reminders to those who drive infrequently, 
and to further the uniformity and harmoniza- 
tion of symbols. It should be noted that the 
turn signal was inadvertently omitted from Table 
I. It was, however, listed in S5.1 as one of the 
hand-operated controls and discussed in the pre- 
amble. 

Another question that was raised was whether 
the manufacturers could use symbols that deviate 
from those designated in the standard. As stated 
in previous notices on controls and displays, 
minor deviations are allowed, as long as the 
symbol used substantially resembles that specified 
in the standard. 

Several commenters raised concerns about the 
color of various symbols. The hazard warning 
telltale was inadvertently designated as green 
in the proposed rule. That color should be red 
and the final rule has been corrected to reflect 
this. Several commenters mentioned that because 
of the technology of light emitting diodes, tell- 
talas are technologically feasible only in yellow, 
green, or red. One commenter noted that neon 
gas discharge displays emit a characteristic neon 
red-orange light, rather than red. These dis- 
plays rate high in intensity, durability, and 
reliability and are low in cost. Because of these 
factors, the final rule has been amended so that 
a designation of the color red can be either red 
or red-orange and the color blue may be either 
blue or blue-green. 

Many of those commenting objected to the 
prohibition of any words other than the words 
specified in the table. The NHTSA has decided, 
to permit the manufacturer to use additional 
words, but only for clarification. For example, 
tlie manufacturer may combine an instruction 
with the specified identification, such as "pull to 
defrost," or it may use another word for the 
purpose of clarity, such as "unleaded fuel only." 



PART 571; S 101-80— PRE 2 



PREAMBLE TO FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 101-80 



Controls and Displays 
(Docket No. 1-18; Notice 13) 



Action: Final rule. 



Summary: This notice expands the applica- 
tion of the standard for the location, identifica- 
tion, and illumination of driver controls and 
displays (e.g., gauges and meters) by establishing 
requirements for additional controls and by in- 
troducing selected displays which, if furnished, 
must be located and illuminated under specified 
conditions and identified by a specified symbol 
and/or selected word. The purpose of the re- 
quirements is to encourage international stand- 
ardization and liarmonization of controls and 
displays in order to convey information more 
quickly to drivers and with less chance of human 
error. This will reduce the interval during which 
a driver's attention is diverted from the roadway 
to his controls and displays, thus decreasing the 
possibility of an accident. 

E-ffective date: September 1, 1980. 

For further informatwn contact : 

Mr. Nelson Erickson, Office of Motor Vehicle 
Programs, 400 Seventh Street, S.W., "Wash- 
ington, D.C. 20590, 202-426-2155. 

Supplementary infoy^mation: This notice estab- 
lishes new requirements for the location, identifi- 
cation, and illumination of controls and displays 
in passenger care, multipui-pose passenger ve- 
hicles, trucks, and buses. The new rule is desig- 
nated 49 CFR 571.101-80, Controls and Displays, 
and becomes effective September 1, 1980. The 
existing rule on this subject, 49 CFR 571.101, 
Control Location, Identification, and Illumina- 
tion, is amended to permit, at the vehicle 
manufacturer's option, compliance with that 
standard or the new requirements of Standard 
No. 101-80 before September 1, 1981. 



On October 21, 1976, the National Highway 
Traffic Safety Administration published (41 FR 
46460) a notice proposing to update the existing 
controls and displays standard (Standard 101) 
by incorporating all pertinent amendments and 
interpretations published since the original issu- 
ance on January 31, 1967. It also proposed to 
consolidate the control and display requirements 
of other standards in one regulation. This notice 
takes final action on that proposal. All com- 
ments were considered and the major ones are 
discussed below. 

The notice issued in October 1976 proposed 
that most controls and displays be required to 
be identified with specified symbols which are 
internationally standardized. Words would have 
been permitted in addition to the symbols, 
although the choice of words would have been 
limited to ensure uniformity. Specified words 
would have been required for those controls and 
displays for which no symbols had been estab- 
lished. 

The rationale behind the proposed requirement 
of symbols was that they can convey information 
more quickly and with less chance of human 
error than words. This is particularly true with 
respect to the large foreign language speaking 
population of this country. By simplifying the 
identification of controls and displays, the stand- 
ard should reduce the problems resulting from 
driver's attention being diverted from the road- 
way to his controls and displays. An individual 
benefit cited in the proposed notice is that manu- 
facturers wlio sell vehicles both in and outside 
of the United States could realize significant 
cost savings by utilizing internationally stand- 
ardized symbols. 



PART 571; S 101-80— PRE 1 



The National Motor Vehicle Advisory Council 
and the Vehicle Equipment Safety Commission 
did not take positions on the proposal. The ma- 
jority of commenters favored the use of symbols 
in the interest of international standardization 
and hannonization. The final rule, therefore, re- 
quires the use of symbols and allows the use of 
additional words if the manufacturer so chooses. 

One of the major concerns of manufacturers 
commenting was that the proposed rule would 
inhibit the design and development of electronic 
"readout" panels which can effectively present 
to the driver specific information concerning ve- 
hicle and environmental conditions affecting 
safety. These displays are currently capable of 
exhibiting information and warnings with word 
messages and not with symbols. The optional 
use of symbols or words will permit the con- 
tinued development of informational readout 
displays. The NHTSA supports the develop- 
ment of more efficient and effective control and 
display information systems and has, conse- 
quently, permitted informational readout dis- 
plays to be identified by words only so as to not 
impede the development of electronic displays. 

The symbols that are permitted by this rule 
to identify controls and displays are those de- 
veloped by the International Standards Organi- 
zation (ISO). By specif3ang symbols adopted 
by the ISO, this agency is facilitating the 
achievement of an international unifomi identifi- 
cation system. New symbols for five controls 
and eight displays are added to those presently 
designated in the existing standard. Additional 
symbols will be added when the NHTSA deter- 
mines which ones will be readily recognizable, 
thus reducing driver diversion. 

Some commenters noted that a few of the 
symbols such as the clearance lamp symbol, de- 
viate slightly from those adopted by the ISO. 
The NHTSA, while basing its symbols on those 
developed by the ISO, is not specifying ISO 
symbols which it determines will not adequately 
convey the intended message. Thus, the symbols 
proposed in the October notice are adopted, 
even though some of them deviate from the ISO 
symbols. Some existing ISO symljols are not 
included in this final rule due to the fact that 
additional data are needed on their recogniza- 
bility. When such data have been accumulated 



and analyzed, the NHTSA will determine 
whether the symbols should be added to Stand- 
ard 101-80. 

A few commenters suggested the deletion of 
the symbols for the turn signal and high beam 
telltales because these have long been identified 
by color and operate only after deliberate opera- 
tion by the driver. It is the belief of the 
NHTSA that these symbols should be retained. 
They are necessary to educate new drivers, to 
act as reminders to those who drive infrequently, 
and to further the uniformity and harmoniza- 
tion of symbols. It should be noted that the 
turn signal was inadvertently omitted from Table 
I. It was, however, listed in S5.1 as one of the 
hand-operated controls and discussed in the pre- 
amble. 

Another question that was raised was whether 
the manufacturers could use symbols that deviate 
from those designated in the standard. As stated 
in previous notices on controls and displays, 
minor deviations are allowed, as long as the 
symbol used substantially resembles that specified 
in the standard. 

Several commenters raised concerns about the 
color of various symbols. The hazard warning 
telltale was inadvertently designated as green 
in the proposed rule. That color should be red 
and the final rule has been corrected to reflect 
this. Several commenters mentioned that because 
of the teclmology of light emitting diodes, tell- 
tales are technologically feasible only in yellow, 
green, or red. One commenter noted that neon 
gas discharge displays emit a characteristic neon 
red-orange light, rather than red. These dis- 
plays rate high in intensity, durability, and 
reliability and are low in cost. Because of these 
factors, the final rule has been amended so that 
a designation of the color red can be either red 
or red-orange and tlie color blue may be either 
blue or blue-green. 

Many of those commenting objected to the 
prohibition of any words other than the words 
specified in the table. The NHTSA has decided, 
to permit the manufacturer to use additional 
words, but only for clarification. For example, 
tlie manufacturer may combine an instruction 
with the specified identification, such as "pull to 
defrost," or it may use another word for the 
purpose of clarity, such as "unleaded fuel only." 



PART 571; S 101-80— PRE 2 



The manufacturer will be permitted to describe 
the "automatic vehicle speed system" in words 
of his choosing because over the years customers 
have become used to the various descriptors, such 
as "cruise control" and "speed control," which 
manufacturers have used. The NHTSA does 
not believe that either descriptor is superior to 
the other. In addition, the manufacturer will 
be permitted to describe the "automatic gear posi- 
tion" by words of his choosing since these con- 
trols are conspicuous and automatic transmissions 
are not imiform, some not providing a park (P) 
position and others with additional gears. In 
response to one question, it should be noted that 
"automatic gear position" by virtue of its being 
automatic is not a hand-operated control as re- 
ferred to in S5.3.1. 

In accordance with the suggestions of com- 
menters, the final rule adopts the use of "volts" 
or "charge" in addition to "amp" for the elec- 
trical charge telltale and gauge. Many other 
alternate words were suggested, but the NHTSA 
believes that the ones adopted in the final rule 
best convey the appropriate information. With 
the allowance of additional words, objection to 
those required should no longer remain. 

Manufacturers of vehicles over 10,000 pounds 
gross vehicle weight rating (GVWR) objected 
to the application of this rule to their vehicles. 
They emphasized that with the increased number 
of gauges and expanded level of display infor- 
mation utilized by such vehicles, the application 
of this rule would result in panels that are a 
"hodgepodge of symbols." It was also asserted 
that this application would necessitate redesign 
of the instrument panels, possibly increasing 
driver diversion instead of decreasing it. Most 
heavy duty trucks comply with SAE recom- 
mendations for the location standardization of 
controls and displays in the operator's compart- 
ment. The operators of vehicles in the heavy 
duty category are professionals who are familiar 
with these standardized locations and do not need 
to read a legend or symbol. In addition, heavy 
duty trucks are not subject to yearly redesign 
or model changes. Because of these concerns, 
the agency has decided that vehicles over 10,000 
pounds GVWR need not meet display require- 
ments of this standard. They must, however, 
meet the control requirements. 



A large number of commenters requested that 
the location of the controls and displays be uni- 
form. An additional request was made to require 
common carriers to maintain illumination devices 
on all equipment. While these recommendations 
are noteworthy, they are not the subject of this 
rulemaking action, but will be considered for 
possible future rulemaking. 

In the October proposal, it was specfied that 
the control identification be placed on or adjacent 
to the particular control. The display identifica- 
tion, on the other hand, was to be placed on the 
display, unless the exposed portion of the lens 
was in the shape of the required identification. 
The proposal also stated that the identification 
of the high-beam indicator and of any gauge 
could be placed on or adjacent to the display 
that it identified. In response to the comments 
that identification could be met equally well by 
placing the symbol adjacent to the telltale, the 
NHTSA has decided to leave it up to the manu- 
facturer to determine whether the identification 
should be placed directly on the control or dis- 
play or whether an adjacent position would be 
satisfactory. The final rule does require that the 
identification be visible to the driver. In re- 
sponse to one commenter, the NHTSA does 
recognize that the spokes of the steering wheel 
may at times interfere with the visibility of the 
controls and displays. The visibility require- 
ment will be satisfied even if the driver needs 
to make minimal movements toward the front, 
to the left, and to the right to see the identifica- 
tions. The NHTSA has determined that these 
minor necessary movements will have virtually 
no effect on the safe operation of the vehicle. 

The designation of "Km" for kilometres has 
been corrected in the final rule to read "km". 
Any odometer that records distance in kilometres 
must be labeled "KILOMETRES" or "km" so 
as to avoid confusion. The October 1976 pro- 
posal provided an option regarding English or 
metric units for labeling speedometers. Any 
proposal setting forth alternatives implicitly car- 
ries with it the possibility that one or more of 
the alternatives may become mandatory. In 
light of this and in light of the decision in Fed- 
eral Motor Veliicle Safety Standard No. 127, 
43 FR 10919, to require speedometers to record 
speed in both English and in metric, this rule 



PART 571; S 101-80— PRE 3 



requires that both speed scales be labeled so as 
to avoid confusion. Therefore, for dual readings 
of MPH and kmA on speedometers the manu- 
facturer is required to clearly label the appro- 
priate display. 

The proposed effective date for this rule was 
September 1, 1979. Due to the numerous com- 
ments received, indicating that more lead time 
would be desirable in order to permit the conver- 
sion of controls and displays to coincide with 
routine redesign of various vehicle models, an 
effective dat« of September 1, 1980, has been 
adopted. 

The primary authors of this notice are Mr. 
Nelson Erickson, Office of Motor Vehicle Pro- 



grams, and Ms. Kathleen DeMeter, OflSce of the 
Chief Counsel. 

In consideration of the foregoing. Part 571 
of Title 49 of the Code of Federal Regulations 
is amended. . . . 

(Sees. 103, 119, Pub. L. 89-563, 80 Stat. 718 
(15 U.S.C. 1392, 1407) ; delegation of authority 
at 49 CFR 1.50.) 

Issued on June 21, 1978. 

Joan Claybrook 
Administrator 

43 F.R. 27541 
June 26, 1978 



PART 571; S 101-80— PRE 4 



The manufacturer will be permitted to describe 
the "automatic vehicle speed system" in words 
of his choosing because over the years customers 
have become used to the various descriptors, such 
as "cruise control" and "speed control," which 
manufacturers have used. The NHTSA does 
not believe that either descriptor is superior to 
the other. In addition, the manufacturer will 
be permitted to describe the "automatic gear posi- 
tion" by words of his choosing since these con- 
trols are conspicuous and automatic transmissions 
are not uniform, some not providing a park (P) 
position and others with additional gears. In 
response to one question, it should be noted that 
"automatic gear position" by virtue of its being 
automatic is not a hand-operated control as re- 
ferred to in S5.3.1. 

In accordance with the suggestions of com- 
menters, the final rule adopts the use of "volts" 
or "charge" in addition to "amp" for the elec- 
trical charge telltale and gauge. Many other 
alternate words were suggested, but the NHTSA 
believes that the ones adopted in the final rule 
best convey the appropriate information. With 
the allowance of additional words, objection to 
those required should no longer remain. 

Manufacturers of vehicles over 10,000 pounds 
gross vehicle weight rating (GVWK) objected 
to the application of this rule to their vehicles. 
They emphasized that with the increased number 
of gauges and expanded level of display infor- 
mation utilized by such vehicles, the application 
of this rule would result in panels that are a 
"hodgepodge of symbols." It was also asserted 
that this application would necessitate redesign 
of the instrument panels, possibly increasing 
driver diversion instead of decreasing it. Most 
heavy duty trucks comply with SAE recom- 
mendations for the location standardization of 
controls and displays in the operator's compart- 
ment. The operators of vehicles in the heavy 
duty category are professionals who are familiar 
with these standardized locations and do not need 
to read a legend or symbol. In addition, heavy 
duty trucks are not subject to yearly redesign 
or model changes. Because of these concerns, 
the agency has decided that vehicles over 10,000 
pounds GVWR need not meet display require- 
ments of this standard. They must, however, 
meet the control requirements. 



A large number of commenters requested that 
the location of the controls and displays be uni- 
form. An additional request was made to require 
common carriers to maintain illumination devices 
on all equipment. While these recommendations 
are noteworthy, they are not the subject of this 
rulemaking action, but will be considered for 
possible future rulemaking. 

In the October proposal, it was specfied that 
the control identification be placed on or adjacent 
to the particular control. The display identifica- 
tion, on the other hand, was to be placed on the 
display, unless the exposed portion of the lens 
was in the shape of the required identification. 
The proposal also stated that the identification 
of the high-beam indicator and of any gauge 
could be placed on or adjacent to the display 
that it identified. In response to the comments 
that identification could be met equally well by 
placing the symbol adjacent to the telltale, the 
NHTSA has decided to leave it up to the manu- 
facturer to determine whether the identification 
should be placed directly on the control or dis- 
play or whether an adjacent position would be 
satisfactory. The final rule does require that the 
identification be visible to the driver. In re- 
sponse to one commenter, the NHTSA does 
recognize that the spokes of the steering wheel 
may at times interfere with the visibility of the 
controls and displays. The visibility require- 
ment will be satisfied even if the driver needs 
to make minimal movements toward the front, 
to the left, and to the right to see the identifica- 
tions. The NHTSA has determined that the,se 
minor necessary movements will have virtually 
no effect on the safe operation of the vehicle. 

The designation of "Km" for kilometres has 
been corrected in the final rule to read "km". 
Any odometer that records distance in kilometres 
must be labeled "KILOMETRES" or "km" so 
as to avoid confusion. The October 1976 pro- 
posal provided an option regarding English or 
metric units for labeling speedometers. Any 
proposal setting forth alternatives implicitly car- 
ries with it the possibility that one or more of 
the alternatives may become mandatory. In 
light of this and in light of the decision in Fed- 
eral Motor Vehicle Safety Standard No. 127, 
43 FR 10919, to require speedometers to record 
speed in both English and in metric, this rule 



PART 571; S 101-80— PRE 3 



requires that both speed scales be labeled so as 
to avoid confusion. Therefore, for dual readings 
of MPH and km/h on speedometers the manu- 
facturer is required to clearly label the appro- 
priate display. 

The proposed effective date for this rule was 
September 1, 1979. Due to the numerous com- 
ments received, indicating that more lead time 
would be desirable in order to permit the conver- 
sion of controls and displays to coincide with 
routine redesign of various vehicle models, an 
effective date of September 1, 1980, has been 
adopted. 

The primary authors of this notice are Mr. 
Nelson Erickson, Office of Motor Vehicle Pro- 



grams, and Ms. Kathleen DeMeter, OflSce of the 
Chief Counsel. 

In consideration of the foregoing, Part 571 
of Title 49 of the Code of Federal Regulations 
is amended. . . . 

(Sees. 103, 119, Pub. L. 89-563, 80 Stat. 718 
(15 U.S.C. 1392, 1407); delegation of authority 
at 49 CFR 1.50.) 

Issued on June 21, 1978, 

Joan Claybrook 
Administrator 

43 F.R. 27541 
June 26, 1978 



PART 571; S 101-80— PRE 4 



PREAMBLE TO AN AMENDMENT TO 
FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 101-80 



Control and Display 
(Docket 1-18; Notice 18) 



ACTION: Interpretative amendment. 



SUMMARY: Standard No. 101-80, Controls and 
Displays, requires various safety-related controls 
to be identified by specific symbols. The standard 
requires identification of the turn signal control 
unless it is the only control on the left hand side of 
the steering column. In addition to the turn signal 
control, some vehicles have additional controls, 
such as a lever to adjust the position of a tilting 
steering wheel, on the left hand side of the col- 
umn. This notice clarifies the identification re- 
quirement to provide that a turn signal control 
does not have to be identified if it is the topmost 
control on the left side of the steering column, the 
traditional position for such controls (i.e., the 
closest control to the steering wheel). 

EFFECTIVE DATE: Date of Publication in the Oc- 
tober 30, 1980 Federal Register. 

FOR FURTHER INFORMATION CONTACT: 

John Carson, Office of Vehicle Safety 
Standards, National Highway Traffic Safety 
Administration, 400 Seventh Street, S.W., 
Washington, D.C. 20590 (202-426-2715) 

SUPPLEMENTARY INFORMATION: On June 26, 
1978, the agency published a final rule establish- 
ing Standard No. 101-80, Controls and Displays 
(43 FR 27541). The standard, which went into 
effect on September 1, 1980, established new 
identification and illumination requirements for 
controls and displays in passenger cars, multipur- 
pose passenger vehicles, trucks and buses. 

One provision of the standard requires the turn 
signal control to be identified by a specific sym- 
bol, two horizontal arrowheads, placed on or adja- 
cent to the control. American Motors Corporation 
(AMC) filed a petition for reconsideration arguing 



that the turn signal identification requirement 
was unnecessary. AMC said that the location and 
operation of column-mounted turn signal control 
levers has been standardized by industry practice 
and is well known to drivers. In response to the 
AMC petition, NHTSA amended the standard to 
delete the identification requirement for vehicles 
in which the turn signal control is the only lever 
mounted on the left side of the steering column. 
The agency explained that it was taking this ac- 
tion because the turn signal control has become 
standardized at that location and there have been 
no reported crashes caused by the driver's un- 
familiarity with the position and use of the turn 
signal control (Sept. 27, 1979, 44 FR 55580). 

Subsequent to the publication of the response 
to the AMC petition for reconsideration. General 
Motors (GM) wrote the agency concerning an in- 
terpretation of the modified requirements. GM 
said that on its vehicles equipped with tilt steer- 
ing columns, there is a tilt mechanism release 
lever located on the same side of the steering col- 
umn as the turn signal control lever. GM said that 
the tilt release lever is "shorter and significantly 
farther from the steering wheel than the turn sig- 
nal lever and consequently is out of the imme- 
diate finger tip reach of a hand remaining on the 
steering wheel." GM said that the tilt wheel 
mechanism is a customer convenience, not a safe- 
ty feature. 

GM argued that its understanding of the agen- 
cy's interpretation of the modified identification 
requirement was that the turn signal control only 
had to be identified "if it is not located and 
operated in what has become to be considered the 
standardized manner or if another functional con- 
trol lever related to vehicle safety could be easily 
confused with it." GM said that based on that in- 
terpretation, it believed that "the presence or 
absence of a tilt column release lever does not 



PART 571; S101-80-PRE 5 



determine whether the turn signal control must be 
identified." To assist all interested parties in inter- 
preting the requirement, GM requested the agency 
to consider revising the language of the standard 
to clarify the agency's intent. 

The purpose of this notice is to make an inter- 
pretative amendment to Standard No. 101-80 to 
clarify the circumstances under which the turn 
signal control must be identified. As an inter- 
pretative amendment, there is no need for notice 
and comment. 

The purpose of the identification requirement is 
to make it easier for the driver to quickly and cor- 
rectly locate various safety-related vehicle con- 
trols. One of the controls that has been standard- 
ized in its location and operation for a number of 
years is the turn signal control. In every car, that 
control is mounted on the left hand side of the 
steering column, is located so that it is the control 
closest to the rim of the steering wheel, and is 
operated in a standardized manner, up for right, 
down for left. Since the turn signal control has 
been standardized for such a long time, it is not 
necessary for the control to include an identifying 
symbol. 



As long as the turn signal control is in its 
standardized location, it will be instantly recog- 
nized by drivers even if there are other controls 
mounted on the same side of the column, farther 
away from the rim of the steering wheel. Thus, to 
clarify the iden-tification requirements, the agency 
is amending the standard. The amendment pro- 
vides that if the turn signal control is mounted on 
the left side of the steering column, in a plane 
essentially parallel to the steering wheel, it need 
not be identified if it is the control mounted closest 
to the rim of the steering wheel. 

In consideration of the foregoing, Standard No. 
101-80 (49 CFR 571.101-80) is revised accordingly. 

Issued on October 22, 1980. 



Frank Berndt 
Acting Administrator 

45 FR 71803 
October 30, 1980 



PART 571; S101-80-PRE 6 



PREAMBLE TO AN AMENDMENT TO 
FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 101-80 



Control and Display 
(Docket 1-18; Notice 18) 



ACTION: Interpretative amendment. 



SUMMARY: Standard No. 101-80, Controls and 
Displays, requires various safety-related controls 
to be identified by specific symbols. The standard 
requires identification of the turn signal control 
unless it is the only control on the left hand side of 
the steering column. In addition to the turn signal 
control, some vehicles have additional controls, 
such as a lever to adjust the position of a tilting 
steering wheel, on the left hand side of the col- 
umn. This notice clarifies the identification re- 
quirement to provide that a turn signal control 
does not have to be identified if it is the topmost 
control on the left side of the steering column, the 
traditional position for such controls (i.e., the 
closest control to the steering wheel). 

EFFECTIVE DATE: Date of Publication in the Oc- 
tober 30, 1980 Federal Register. 

FOR FURTHER INFORMATION CONTACT: 

John Carson, Office of Vehicle Safety 
Standards, National Highway Traffic Safety 
Administration, 400 Seventh Street, S.W., 
Washington, D.C. 20590 (202-426-2715) 

SUPPLEMENTARY INFORMATION: On June 26, 
1978, the agency published a final rule establish- 
ing Standard No. 101-80. Controls and Displays 
(43 FR 27541). The standard, which went into 
effect on September 1, 1980, established new 
identification and illumination requirements for 
controls and displays in passenger cars, multipur- 
pose passenger vehicles, trucks and buses. 

One provision of the standard requires the turn 
signal control to be identified by a specific sym- 
bol, two horizontal arrowheads, placed on or adja- 
cent to the control. American Motors Corporation 
(AMC) filed a petition for reconsideration arguing 



that the turn signal identification requirement 
was unnecessary. AMC said that the location and 
operation of column-mounted turn signal control 
levers has been standardized by industry practice 
and is well known to drivers. In response to the 
AMC petition, NHTSA amended the standard to 
delete the identification requirement for vehicles 
in which the turn signal control is the only lever 
mounted on the left side of the steering column. 
The agency explained that it was taking this ac- 
tion because the turn signal control has become 
standardized at that location and there have been 
no reported crashes caused by the driver's un- 
familiarity with the position and use of the turn 
signal control (Sept. 27, 1979, 44 FR 55580). 

Subsequent to the publication of the response 
to the AMC petition for reconsideration, General 
Motors (GM) wrote the agency concerning an in- 
terpretation of the modified requirements. GM 
said that on its vehicles equipped with tilt steer- 
ing columns, there is a tilt mechanism release 
lever located on the same side of the steering col- 
umn as the turn signal control lever. GM said that 
the tilt release lever is "shorter and significantly 
farther from the steering wheel than the turn sig- 
nal lever and consequently is out of the imme- 
diate finger tip reach of a hand remaining on the 
steering wheel." GM said that the tilt wheel 
mechanism is a customer convenience, not a safe- 
ty feature. 

GM argued that its understanding of the agen- 
cy's interpretation of the modified identification 
requirement was that the turn signal control only 
had to be identified "if it is not located and 
operated in what has become to be considered the 
standardized manner or if another functional con- 
trol lever related to vehicle safety could be easily 
confused with it." GM said that based on that in- 
terpretation, it believed that "the presence or 
absence of a tilt column release lever does not 



PART 571; S101-80-PRE 5 



determine whether the turn signal control must be 
identified." To assist all interested parties in inter- 
preting the requirement, GM requested the agency 
to consider revising the language of the standard 
to clarify the agency's intent. 

The purpose of this notice is to make an inter- 
pretative amendment to Standard No. 101-80 to 
clarify the circumstances under which the turn 
signal control must be identified. As an inter- 
pretative amendment, there is no need for notice 
and comment. 

The purpose of the identification requirement is 
to make it easier for the driver to quickly and cor- 
rectly locate various safety-related vehicle con- 
trols. One of the controls that has been standard- 
ized in its location and operation for a number of 
years is the turn signal control. In every car, that 
control is mounted on the left hand side of the 
steering column, is located so that it is the control 
closest to the rim of the steering wheel, and is 
operated in a standardized manner, up for right, 
down for left. Since the turn signal control has 
been standardized for such a long time, it is not 
necessary for the control to include an identifying 
symbol. 



As long as the turn signal control is in its 
standardized location, it will be instantly recog- 
nized by drivers even if there are other controls 
mounted on the same side of the column, farther 
away from the rim of the steering wheel. Thus, to 
clarify the iden-tification requirements, the agency 
is amending the standard. The amendment pro- 
vides that if the turn signal control is mounted on 
the left side of the steering column, in a plane 
essentially parallel to the steering wheel, it need 
not be identified if it is the control mounted closest 
to the rim of the steering wheel. 

In consideration of the foregoing. Standard No. 
101-80 (49 CFR 571.101-80) is revised accordingly. 

Issued on October 22, 1980. 



Frank Berndt 
Acting Administrator 

45 FR 71803 
October 30, 1980 



PART 571; S101-80-PRE 6 



PREAMBLE TO AN AMENDMENT TO PART 571 STANDARD NO. 101-80 

Controls and Displays 
(Docket No. 1-18; Notice 20) 



ACTION: Final rule. 

SUMMARY: This notice amends Standard No. 
101-80, Controls and Displays. The standard 
currently requires the light indicating the 
actuation of the headlamp high beam to be blue. 
(Blue is defined by the standard to include blue- 
green.) This amendment permits manufacturers 
to use the color green as an alternative to blue. 
The purpose of the change is to allow the use of 
light emitting diode technology, which at the 
present time cannot produce the color blue or 
blue-green. 

EFFECTIVE DATE: January 21. 1982. 

SUPPLEMENTARY INFORMATION: Standard 
No. 101-80, Controls and Displays, specifies 
requirements for the identification and 
illumination of controls and displays in passenger 
cars, multipurpose passenger vehicles, trucks and 
buses. The purpose of the standard is to ensure the 
accessibility and visibility of motor vehicle 
controls and displays and to facilitate their quick 
and proper identification and selection by a 
driver in order to reduce the safety hazards 
caused by the diversion of the driver's attention 
from the driving task, and by mistakes in 
selecting controls. 

Among its requirements. Standard No. 101-80 
specifies colors for various vehicle displays. Blue 
is specified for the headlamp high beam telltale 
(i.e., the light indicating that the high beams of 
the headlamps have been activated). A footnote to 
the standard's color requirements (contained in 
Table 2 of the standard) states that blue can be 
blue-green. 

This final rule amends the standard by adding 
green as an alternative to blue and blue-green for 
the headlamp high beam telltale. This final rule 



was preceded by a notice proposing the 
amendment of Standard No. 101-80 in October 1980 
(45 F.R. 71832). Several comments were received 
that supported the proposal, including those 
submitted by General Motors, Ford and Chrysler. 
Only one comment opposed the proposal. The 
NHTSA has considered all of the comments and 
the most significant ones are discussed below. 

The agency proposed to allow the use of green 
as an alternative to blue in response to a petition 
for rulemaking from Volkswagen (VW). Blue had 
been selected by the agency for the headlamp 
high beam telltale primarily to promote 
international harmonization of standards 
regulating vehicle controls and displays. That 
color requirement was the same as that adopted 
by the International Standards Organization, the 
Economic Commission for Europe and the 
European Economic Community. VW petitioned 
for green as an alternative to blue in order to 
enable it to use light emitting diodes (LED's) for 
its telltales. VW stated that its testing has 
demonstrated that LED's are more reliable than 
incandescent bulbs when used for telltales and 
are, thus, very desirable. At present, however, 
LED's cannot be produced in either blue or white 
(which could be used with a blue filter to produce 
blue). VW stated that green is the only color akin 
to blue or blue-green which LED technology is 
capable of producing. 

Ford stated that it supports the proposed 
amendment since it recognizes current 
technological limitations and would allow 
manufacturers to introduce new designs at these 
limits. Ford did express concern, however, that 
the proposed relaxation of the color requirement 
is in conflict with international harmonization of 
U.S. and European motor vehicle standards. That 
company recommended that the proposed 
amendment is issued for an interim period only — 



PART 571: S101-80-PRE 7 



until LED technology can provide commercially 
acceptable blue LED's. Ford's comment stated 
that it believes that blue LED's will become 
commercially feasible for automotive application 
within the next year. 

A comment submitted by General Motors (GM), 
also supporting the proposed amendment, stated 
that it believes that the allowance of a green high 
beam telltale will effectively present the message 
of that telltale, particularly since it must also be 
identified by a symbol. According to GM, the 
amendment will allow incorporation of the current 
electronic technology involving light emitting 
diodes into automotive panel displays. GM stated 
that the allowance of green as a high beam telltale 
color will not affect international harmonization 
since blue will remain an alternative. That 
company noted that any manufacturer desiring to 
market a product worldwide can still choose to 
use a blue telltale and thereby meet the 
international requirements. 

The issue of conflict with international 
harmonization was the basis for the only 
comment received in opposition to the proposed 
amendment. The U.S. Technical Research 
Company (U.S. Technical Representatives of 
Peugeot) stated that under the present state of 
technology, LED's can only display yellow, green 
or red. That company stated that it believes that 
in the near future an amendment of European 
regulations wUl require that the high beam telltale 
shall be either blue or yellow. According to that 
commenter, if NHTSA chooses to adopt green for 
the high beam telltale, harmonization in this field 
will no longer exist and domestic and foreign 
manufacturers will be equally affected. The U.S. 
Technical Research Company therefore requested 
that NHTSA retain the blue requirement because 
it is identical to the current European 
requirement. Alternatively, that company asked 
the agency to require that either blue or yellow 
telltales be used in anticipation of the possible 
change in the European requirements. 

In the interest of international harmonization 
of standards, Renault also supported permitting 
the use of yellow. However, it also supported 
allowing the use of green as an alternative to 
blue. 

The purpose of requiring telltales to be of a 
particular color is to promote standardization and 
thereby improve driver performance. As noted 



above, the agency adopted blue for the high beam 
telltale primarily to promote international 
harmonization. The International Standards 
Organization, the Economic Commission for 
Europe and the European Economic Community 
all maintain that color requirement. 

The agency does not believe that permitting 
the use of green as an alternative to blue is in 
conflict with international harmonization. As 
noted by GM, any manufacturer desiring to 
market a product worldwide can still choose to 
use a blue telltale and thereby meet the 
international requirements. While the agency is 
aware that some manufacturers and some 
countries in Europe have sought to have 
international standards amended to permit use of 
yellow as an alternative to blue, it is by no means 
certain that those efforts will succeed. Indeed, 
the International Standards Organization rejected 
such a proposal in April 1980. 

In light of the uncertainty of the direction in 
which international requirements will move on 
this matter, the agency determined that yellow 
should not be adopted as an alternative to blue. 
The agency agrees with VW's petition that green 
is the closest color akin to blue or blue-green that 
LED's can produce and thus, in the agency's . 
judgment, is the best alternative color to permit. ' 
To permit use of yellow as well would defeat the 
purpose of having a color requirement in the first 
place, that of promoting standardization and 
thereby improving driver performance. Therefore, 
that alternative was rejected. 

The agency recognizes that the cause of 
international harmonization may make amendment 
of Standard No. 101-80 appropriate if international 
organizations adopt yellow as an alternative to 
blue. The agency will monitor developments in 
this area. 

In the interest of both standardization and 
international harmonization, the agency believes 
that use of green as an alternative to blue should 
only be permitted until LED technology develops 
to the point that it is possible to produce 
commercially acceptable blue LED's. The agency 
considered amending the standard to permit use 
of green for a specified period of time, such as 
three years. However, without more definite 
information indicating when commercially 
acceptable blue LED's will be available, the 
agency determined that it would be more 



PART 571: S101-80-PRE 8 



PREAMBLE TO AN AMENDMENT TO PART 571 STANDARD NO. 101-80 

Controls and Displays 
(Docket No. 1-18; Notice 20) 



ACTION: Final rule. 

SUMMARY: This notice amends Standard No. 
101-80, Controls and Displays. The standard 
currently requires the light indicating the 
actuation of the headlamp high beam to be blue. 
(Blue is defined by the standard to include blue- 
green.) This amendment permits manufacturers 
to use the color green as an alternative to blue. 
The purpose of the change is to allow the use of 
light emitting diode technology, which at the 
present time cannot produce the color blue or 
blue-green. 

EFFECTIVE DATE: January 21, 1982. 

SUPPLEMENTARY INFORMATION: Standard 
No. 101-80, Controls and Displays, specifies 
requirements for the identification and 
illumination of controls and displays in passenger 
cars, multipurpose passenger vehicles, trucks and 
buses. The purpose of the standard is to ensure the 
accessibility and visibility of motor vehicle 
controls and displays and to facilitate their quick 
and proper identification and selection by a 
driver in order to reduce the safety hazards 
caused by the diversion of the driver's attention 
from the driving task, and by mistakes in 
selecting controls. 

Among its requirements. Standard No. 101-80 
specifies colors for various vehicle displays. Blue 
is specified for the headlamp high beam telltale 
(i.e., the light indicating that the high beams of 
the headlamps have been activated). A footnote to 
the standard's color requirements (contained in 
Table 2 of the standard) states that blue can be 
blue-green. 

This final rule amends the standard by adding 
green as an alternative to blue and blue-green for 
the headlamp high beam telltale. This final rule 



was preceded by a notice proposing the 
amendment of Standard No. 101-80 in October 1980 
(45 F.R. 71832). Several comments were received 
that supported the proposal, including those 
submitted by General Motors, Ford and Chrysler. 
Only one comment opposed the proposal. The 
NHTSA has considered all of the comments and 
the most significant ones are discussed below. 

The agency proposed to allow the use of green 
as an alternative to blue in response to a petition 
for rulemaking from Volkswagen (VW). Blue had 
been selected by the agency for the headlamp 
high beam telltale primarily to promote 
international harmonization of standards 
regulating vehicle controls and displays. That 
color requirement was the same as that adopted 
by the International Standards Organization, the 
Economic Commission for Europe and the 
European Economic Community. VW petitioned 
for green as an alternative to blue in order to 
enable it to use light emitting diodes (LED's) for 
its telltales. VW stated that its testing has 
demonstrated that LED's are more reliable than 
incandescent bulbs when used for telltales and 
are, thus, very desirable. At present, however, 
LED's cannot be produced in either blue or white 
(which could be used with a blue filter to produce 
blue). VW stated that green is the only color akin 
to blue or blue-green which LED technology is 
capable of producing. 

Ford stated that it supports the proposed 
amendment since it recognizes current 
technological limitations and would allow 
manufacturers to introduce new designs at these 
limits. Ford did express concern, however, that 
the proposed relaxation of the color requirement 
is in conflict with international harmonization of 
U.S. and European motor vehicle standards. That 
company recommended that the proposed 
amendment is issued for an interim period only — 



PART 571; S101-80-PRE 7 



until LED technology can provide commercially 
acceptable blue LED's. Ford's comment stated 
that it believes that blue LED's will become 
commercially feasible for automotive application 
within the next year. 

A comment submitted by General Motors (GM), 
also supporting the proposed amendment, stated 
that it believes that the allowance of a green high 
beam telltale will effectively present the message 
of that telltale, particularly since it must also be 
identified by a symbol. According to GM, the 
amendment will allow incorporation of the current 
electronic technology involving light emitting 
diodes into automotive panel displays. GM stated 
that the allowance of green as a high beam telltale 
color will not affect international harmonization 
since blue will remain an alternative. That 
company noted that any manufacturer desiring to 
market a product worldwide can still choose to 
use a blue telltale and thereby meet the 
international requirements. 

The issue of conflict with international 
harmonization was the basis for the only 
comment received in opposition to the proposed 
amendment. The U.S. Technical Research 
Company (U.S. Technical Representatives of 
Peugeot) stated that under the present state of 
technology, LED's can only display yellow, green 
or red. That company stated that it believes that 
in the near future an amendment of European 
regulations will require that the high beam telltale 
shall be either blue or yellow. According to that 
commenter, if NHTSA chooses to adopt green for 
the high beam telltale, harmonization in this field 
will no longer exist and domestic and foreign 
manufacturers will be equally affected. The U.S. 
Technical Research Company therefore requested 
that NHTSA retain the blue requirement because 
it is identical to the current European 
requirement. Alternatively, that company asked 
the agency to require that either blue or yellow 
telltales be used in anticipation of the possible 
change in the European requirements. 

In the interest of international harmonization 
of standards, Renault also supported permitting 
the use of yellow. However, it also supported 
allowing the use of green as an alternative to 
blue. 

The purpose of requiring telltales to be of a 
particular color is to promote standardization and 
thereby improve driver performance. As noted 



above, the agency adopted blue for the high beam 
telltale primarily to promote international 
harmonization. The International Standards 
Organization, the Economic Commission for 
Europe and the European Economic Community 
all maintain that color requirement. 

The agency does not believe that permitting 
the use of green as an alternative to blue is in 
conflict with international harmonization. As 
noted by GM, any manufacturer desiring to 
market a product worldwide can still choose to 
use a blue telltale and thereby meet the 
international requirements. While the agency is 
aware that some manufacturers and some 
countries in Europe have sought to have 
international standards amended to permit use of 
yellow as an alternative to blue, it is by no means 
certain that those efforts will succeed. Indeed, 
the International Standards Organization rejected 
such a proposal in April 1980. 

In light of the uncertainty of the direction in 
which international requirements will move on 
this matter, the agency determined that yellow 
should not be adopted as an alternative to blue. 
The agency agrees with VW's petition that green 
is the closest color akin to blue or blue-green that 
LED's can produce and thus, in the agency's 
judgment, is the best alternative color to permit. 
To permit use of yellow as well would defeat the 
purpose of having a color requirement in the first 
place, that of promoting standardization and 
thereby improving driver performance. Therefore, 
that alternative was rejected. 

The agency recognizes that the cause of 
international harmonization may make amendment 
of Standard No. 101-80 appropriate if international 
organizations adopt yellow as an alternative to 
blue. The agency will monitor developments in 
this area. 

In the interest of both standardization and 
international harmonization, the agency believes 
that use of green as an alternative to blue should 
only be permitted until LED technology develops 
to the point that it is possible to produce 
commercially acceptable blue LED's. The agency 
considered amending the standard to permit use 
of green for a specified period of time, such as 
three years. However, without more definite 
information indicating when commercially 
acceptable blue LED's will be available, the 
agency determined that it would be more 



PART 571; S101-80-PRE 8 



appropriate to issue the amendment for an 
indefinite period of time. The agency will 
consider limiting high beam telltales to blue after 
blue LED technology has been developed. 

The agency does not believe that this 
amendment will have any adverse effect on 
safety. Even if it did, the effect would be more 
than outweighed by the advantages offered by 
permitting industry the flexibility to use LED 
technology for telltales. As VW pointed out, there 
is evidence that LED's are more reliable than 
incandescent bulbs. 

Comments submitted by Ford and VDO-ARGO 
stated that they see no adverse effect on safety as 
a result of this amendment. Further, as noted 
above, GM stated that it believes that a green 
high beam telltale will effectively present the 
message of that telltale, particularly since it must 
also be identified by symbol. No comments were 
received that suggested any adverse effect. 

Also, there may be cost savings and other 
advantages associated with permitting LED's to 
be used for telltales. Standard No. 101-80 already 
permits LED's to be used for other displays. The 
standard defines displays that use LED's to give 
one or more than one type of information or 
message (i.e., using words or symbols) as 
informational readout displays. Recently the 
agency granted a petition for rulemaking from 
GM that requested modification in Standard No. 
101-80's light intensity requirements to permit 
informational readout displays to be used for 
telltales. According to GM, such an amendment 
would permit integration of telltales with other 
instrument displays in a single electronic display 
panel. This step would alleviate instrument panel 
design problems caused by reduced space available 
due to vehicle downsizing and increasing amounts 
and types of information to be presented to the 
driver, offer potential for weight and cost 
reduction, and facilitate placing telltales adjacent 
to displays often consulted by the driver, making 



the telltales more readily noticeable. These same 
types of advantages are offered by permitting 
displays which use LED's, but are not informational 
readout displays (since they consist only of a 
colored light and do not display words or symbols), 
as telltales. 

The agency has assessed the economic and 
other impacts of this final rule and determined 
that it is neither a major rule within the meaning 
of Executive Order 12291 nor a significant rule 
under the Department of Transportation's 
regulatory policies and procedures. Further, the 
agency concludes that the economic and other 
consequences of this final rule are so minimal as 
not to require preparation of a regulatory 
evaluation. The impact is minimal because the 
amendment does not impose any new requirements 
and does not affect compliance costs. Rather, it 
merely permits manufacturers to use an alternate 
color for the high beam telltale. For the same 
reasons, the agency finds that the amendment 
will have no significant environmental impact. 

Although NHTSA has considered the effects of 
this amendment on small businesses, the agency 
has not prepared a regulatory flexibility analysis. 
Such an analysis is not necessary in this case, 
since the Regulatory Flexibility Act applies only 
to rules for which an NPRM was issued on or 
after January 1, 1981. The NPRM for this final 
rule was published in October 1980. 

Issued on January 2, 1982. 



Raymond A. Peck, Jr. 
Administrator 

47 F.R. 2996 
January 21, 1982 



PART 571; S101-80-PRE 9-10 



i 



appropriate to issue the amendment for an 
indefinite period of time. The agency will 
consider limiting high beam telltales to blue after 
blue LED technology has been developed. 

The agency does not believe that this 
amendment will have any adverse effect on 
safety. Even if it did, the effect would be more 
than outweighed by the advantages offered by 
permitting industry the flexibUity to use LED 
technology for telltales. As VW pointed out, there 
is evidence that LED's are more reliable than 
incandescent bulbs. 

Comments submitted by Ford and VDO-ARGO 
stated that they see no adverse effect on safety as 
a result of this amendment. Further, as noted 
above, GM stated that it believes that a green 
high beam telltale will effectively present the 
message of that telltale, particularly since it must 
also be identified by symbol. No comments were 
received that suggested any adverse effect. 

Also, there may be cost savings and other 
advantages associated with permitting LED's to 
be used for telltales. Standard No. 101-80 already 
permits LED's to be used for other displays. The 
standard defines displays that use LED's to give 
one or more than one type of information or 
message (i.e., using words or symbols) as 
informational readout displays. Recently the 
agency granted a petition for rulemaking from 
GM that requested modification in Standard No. 
101-80's light intensity requirements to permit 
informational readout displays to be used for 
telltales. According to GM, such an amendment 
would permit integration of telltales with other 
instrument displays in a single electronic display 
panel. This step would alleviate instrument panel 
design problems caused by reduced space available 
due to vehicle downsizing and increasing amounts 
and types of information to be presented to the 
driver, offer potential for weight and cost 
reduction, and facilitate placing telltales adjacent 
to displays often consulted by the driver, making 



the telltales more readily noticeable. These same 
types of advantages are offered by permitting 
displays which use LED's, but are not informational 
readout displays (since they consist only of a 
colored light and do not display words or symbols), 
as telltales. 

The agency has assessed the economic and 
other impacts of this final rule and determined 
that it is neither a major rule within the meaning 
of Executive Order 12291 nor a significant rule 
under the Department of Transportation's 
regulatory policies and procedures. Further, the 
agency concludes that the economic and other 
consequences of this final rule are so minimal as 
not to require preparation of a regulatory 
evaluation. The impact is minimal because the 
amendment does not impose any new requirements 
and does not affect compliance costs. Rather, it 
merely permits manufacturers to use an alternate 
color for the high beam telltale. For the same 
reasons, the agency finds that the amendment 
will have no significant environmental impact. 

Although NHTSA has considered the effects of 
this amendment on small businesses, the agency 
has not prepared a regulatory flexibility analysis. 
Such an analysis is not necessary in this case, 
since the Regulatory Flexibility Act applies only 
to rules for which an NPRM was issued on or 
after January 1, 1981. The NPRM for this final 
rule was published in October 1980. 

Issued on January 2, 1982. 



Raymond A. Peck, Jr. 
Administrator 

47 F.R. 2996 
January 21, 1982 



PART 571; S101-80-PRE 9-10 



MOTOR VEHICLE SAFETY STANDARD NO. 102 

Transmission Shift Lever Sequence, Starter Interlock, and Transmission Braking Effect- 
Passenger Cars, Multipurpose Passenger Vehicles, Trucks, and Buses 



51. Purpose and scope. This standard spec- 
ifies the requirements for the transmission shift 
lever sequence, a starter interlock, and for a 
braking effect of automatic transmissions, to re- 
duce the likelihood of shifting errors, starter 
engagement with vehicle in drive position, and to 
provide supplemental braking at speeds below 25 
miles per hour. 

52. Application. This standard applies to pas- 
senger cars, multipurpose passenger vehicles, 
trucks, and buses. 

53. Requirements. 

S3.1 Automatic transmissions. 

S3.1.1 Location of transmission shift lever posi- 
tions on passenger cars. A neutral position shall 
be located between forward drive and reverse 
drive positions. If a steering-column-mounted 
transmission shift lever is used, movement from 
neutral position to forward drive position shall 
be clockwise. If the transmission shift lever 
sequence includes a park position, it shall be lo- 



cated at the end, adjacent to the reverse drive 
position. 

53.1.2 Transmission braking effect. In vehicles 
having more than one forward transmission gear 
ratio, one forward drive position shall provide 
a greater degree of engine braking than the 
highest speed transmission ratio at vehicle speeds 
below 25 miles per hour. 

53.1.3 Starter interlock. The engine starter 
shall be inoperative when the transmission shift 
lever is in a forward or reverse drive position. 

S3.2 Automatic and manual transmissions. 

Indentification of shift lever positions of auto- 
matic transmissions, and of the shift lever pat- 
tern of manual transmissions, except three 
forward speed manual transmissions having the 
standard "H" pattern, shall be permanently dis- 
played in view of the driver. 

32 F.R. 2410 
February 3, 1967 



i 



i 



MOTOR VEHICLE SAFETY STANDARD NO. 102 



Transmission Shift Lever Sequence, Starter Interlock, and Transmission Braking Effect- 
Passenger Cars, Multipurpose Passenger Vehicles, Trucks, and Buses 



51. Purpose and scope. This standard spec- 
ifies the requirements for the transmission shift 
lever sequence, a starter interlock, and for a 
braking effect of automatic transmissions, to re- 
duce the likelihood of shifting errors, starter 
engagement with vehicle in drive position, and to 
provide supplemental braking at speeds below 25 
miles per hour. 

52. Application. This standard applies to pas- 
senger cars, multipurpose passenger vehicles, 
trucks, and buses. 

53. Requirements. 

S3.1 Automatic transmissions. 

S3.1.1 Location of transmission shift lever posi- 
tions on passenger cars. A neutral position shall 
be located between forward drive and reverse 
drive positions. If a steering-column-mounted 
transmission shift lever is used, movement from 
neutral position to forward drive position shall 
be clockwise. If the transmission shift lever 
sequence includes a park position, it shall be lo- 



cated at the end, adjacent to the reverse drive 
position. 

53.1.2 Transmission braking effect. In vehicles 
having more than one forward transmission gear 
ratio, one forward drive position shall provide 
a greater degree of engine braking than the 
highest speed transmission ratio at vehicle speeds 
below 25 miles per hour. 

53.1.3 Starter interlock. The engine starter 
shall be inoperative when the transmission shift 
lever is in a forward or reverse drive position. 

S3.2 Automatic and manual transmissions. 

Indentification of shift lever positions of auto- 
matic transmissions, and of the shift lever pat- 
tern of manual transmissions, except three 
forward speed manual transmissions having the 
standard "H" pattern, shall be permanently dis- 
played in view of the driver. 

32 F.R. 2410 
February 3, 1967 



EffKtlv*: January 1, 1*«* 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 

Windshield Defrosting and Defogging Systems — Passenger Cars, 
Multipurpose Passenger Vehicles, Trucks and Buses 

(Docket Nos. 9, 1-12) 



103 



Motor Vehicle Safety Standard No. 103 (32 
F.R. 2410) requires .that each passenger car and 
multipurpose passenger vehicle manufactured for 
sale in the Continental United States be provided 
with a windshield defrosting and defogging sys- 
tem. A proposal to amend section 371.21 of 
Part 371, Federal Motor Vehicle Safety Stand- 
ards, by amending Standard No. 103, was pub- 
lished in the Federal Register on December 28, 
1967 (32 F.R. 20867). 

Interested persons have been afforded an op- 
portunity to participate in the making of the 
amendment. Their comments, as well as other 
available information, have been carefully con- 
sidered. 

The purpose of the amendment is to increase 
driver visibility, and thereby enhance safe ve- 
hicle performance, by (1) adding test conditions 
and performance requirements for passenger car 
defrosting and defogging systems; and (2) 
broadening the standard's application to cover 
trucks and buses, which were not subject to the 
initial standard. In addition, the standard was 
modified to improve its clarity. 

Paragraph S4.3 in the notice of proposed rule- 
making required testing of passenger car wind- 
shield defrosting and defogging systems in ac- 
cordance with the test conditions specified in 
paragraph 4 of SAE Recommended Practice 
J902, August 1964. Several comments asked that 
this requirement be modified to permit optional 
use of the test conditions set out in paragraph 4 
of SAE Recommended Practice J902a, March 
1967, a revised version of the Recommended Prac- 
tice. The Administrator has determined that 
there are only minor differences between the test 
equipment, instrumentation, conditions and pro- 
cedures in paragraphs 4.1 through 4.4.7 of these 



two versions, and that these minor differences do 
not affect the level of safety attained with the 
use of either one. Accordingly, S4.3 of the notice 
has been changed to permit the use of the demon- 
stration procedures described in paragraphs 4.1 
through 4.4.7 of either SAE Recommended Prac- 
tice J902 or SAE Recommended Practice J902a. 

Another feature of paragraph S4.3 which 
evoked comments was its provision for use of 
the test procedures in section 4 of Recommended 
Practice J902 to the extent they are "applicable 
to" the particular system being tested. Any pos- 
sible ambiguity that might appear upon super- 
ficial examination of the quoted words disappears 
when this requirement is read in conjunction with 
the operative provisions of section 4 of the SAE 
Recommended Practices. Section 4 makes refer- 
ence to certain components that are not incor- 
porated in every passenger car (e.g. defroster 
blowers) . The use of the section 4 test procedures 
is restricted to those procedures "applicable to" 
the particular passenger car system being tested 
to make it clear that procedures which, by their 
terms, apply to components that are not a part 
of the car being tested need not be complied with. 

Three comments asked that paragraph S4.2 
of the standard be changed to permit optional 
use of the defrosted area and defrosting time 
requirements prescribed in section 3 of SAE 
Recommended Practice J902a in lieu of those set 
forth in section 3 of Recommended Practice 
J902. In the notice of proposed rulemaking, 
paragraph S4.2 incorporated, with minor modi- 
fications, the defrosted area and defrosting time 
requirements of Recommended Practice J902. 
Comparison of the two versions of the SAE 
Recommended Practice reveals that there are 
great differences between the areas and times 



PART 571; S 103— PRE 1 



EffKtiva: January I, 1969 



prescribed by J902 and those prescribed by 
J902a. The requests for a change in paragraph 
S4.2 acknowledged that compliance with one pro- 
cedure is not necessarily more difficult than com- 
pliance with the other. The submissions did not 
indicate that adherence to the J902 requirements 
would impose any significant burden or would 
be impracticable in any sense. In view of the 
absence of sufficient substantiation to justify 
changing the standard, paragraph S4.2 has not 
been modified to allow alternative defrosted area 
and defrosting time requirements. 

One comment requested that the standard be 
changed to allow 5 minutes more to meet the 
defrosted area requirements of the critical or "C" 
area. It was said that reasonable performance 
tolerances should be taken into account, and that, 
therefore, the requirement of paragraph 3.1 of 
SAE Recommended Practice J902, as adopted 
in modified form in paragraph S4.2 of the stand- 
ard, that the "C" area must be 80 percent de- 
frosted after 20 minutes of operation should be 
changed to allow manufacturers 25 minutes to 
attain the 80 percent defrosted goal. Such a 
modification would permit a significant reduc- 
tion of the defrosting performance of defrosting 
and defogging systems and this, in turn, would 
be contrary to the interest of safety. While it 
is true that variations in such things as the per- 
formance of the thermostat and the outlet nozzle 
will affect the system's capability to defrost a 
given windshield area within a stated time, there 



is no apparent reason why it is impracticable to 
design and construct the system so that, at a 
minimum performance level, it will comply with 
the requirements of paragraph S4.2. For these 
reasons, the Administrator has rejected this re- 
quest for modification of the standard. 

Many comments submitted suggestions that 
went beyond the scope of the notice. For ex- 
ample, submissions that discussed the problems 
of establishing performance requirements for de- 
frosting and defogging systems on multipur- 
pose passenger vehicles, trucks, and buses were 
received. These, and other comments of this 
nature, will be considered in connection with 
future rulemaking action. 

In consideration of the foregoing, § 371.21 of 
Part 371, Federal Motor Vehicle Safety Stand- 
ards, is amended, effective January 1, 1969, by 
amending Motor Vehicle Safety Standard No. 
103 ... . 

This amendment is made under the authority 
of sections 103 and 119 of the National Traffic 
and Motor Vehicle Safety Act of 1966 (15 U.S.C. 
1392, 1407) and the delegation of authority of 
April 24, 1968. 

Issued in Washington, D. C. on April 24, 1968. 

Lowell K. Bridwell, 

Federal Highway Administrator. 

33 F.R. 6468 
April 27, 1968 



PART 571; S 103— PRE 2 



MMttv*: January 1, }9W 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 

Windshield Defrosting and Defogging Systems — Passenger Cars, 
Multipurpose Passenger Vehicles, Trucks and Buses 

(Docket Nos. 9, 1-12) 



103 



Motor Vehicle Safety Standard No. 103 (32 
F.R 2410) requires .that each passenger car and 
multipurpose passenger vehicle manufactured for 
sale in the Continental United States be provided 
with a windshield defrosting and defogging sys- 
tem. A proposal to amend section 371.21 of 
Part 271, Federal Motor Vehicle Safety Stand- 
ards, by amending Standard No. 103, was pub- 
lished in the Federal Register on December 28, 
1967 (32 F.R. 20867). 

Interested persons have been afforded an op- 
portunity to participate in the making of the 
amendment. Their comments, as well as other 
available information, have been carefully con- 
sidered. 

The purpose of the amendment is to increase 
driver visibility, and thereby enhance safe ve- 
hicle performance, by (1) adding test conditions 
and performance requirements for passenger car 
defrosting and defogging systems; and (2) 
broadening the standard's application to cover 
trucks sind buses, which were not subject to the 
initial standard. In addition, the standard was 
modified to improve its clarity. 

Paragraph S4.8 in the notice of proposed rule- 
making required testing of passenger car wind- 
shield defrosting and defogging systems in ac- 
cordance with the test conditions specified in 
paragraph 4 of SAE Recomimended Practice 
J902, August 1964. Several comments asked that 
this requirement be modified to permit optional 
use of the test conditions set out in paragraph 4 
of SAE Recommended Practice J902a, March 
1967, a revised version of the Recommended Prac- 
tice. The Administrator has determined that 
there are only minor differences between the test 
equipment, instrumentation, conditions and pro- 
cedures in paragraphs 4.1 through 4.4.7 of these 



two versions, and that these minor differences do 
not affect the level of safety attained with the 
use of either one. Accordingly, S4.3 of the notice 
has been changed to permit the use of the demon- 
stration procedures described in paragraphs 4.1 
through 4.4.7 of either SAE Recommended Prac- 
tice J902 or SAE Recommended Practice J902a. 

Another feature of paragraph S4.8 which 
evoked comments was its provision for use of 
the test procedures in section 4 of Recommended 
Practice J902 to the extent they are "applicable 
to" the particular system being tested. Any pos- 
sible ambiguity that might appear upon super- 
ficial examination of the quoted words disappears 
when this requirement is read in conjunction with 
the operative provisions of section 4 of the SAE 
Recommended Practices. Section 4 makes refer- 
ence to certain components that are not incor- 
porated in every passenger car (e.g. defroster 
blowers) . The use of the section 4 test procedures 
is restricted to those procedures "applicable to" 
the particular passenger car system being tested 
to make it clear that procedures which, by their 
terms, apply to components that are not a part 
of the car being tested need not be complied with. 

Three comments asked that paragraph S4.2 
of the standard be changed to permit optional 
use of the defrosted area and defrosting time 
requirements prescribed in section 8 of SAE 
Recommended Practice J902a in lieu of those set 
forth in section 3 of Recommended Practice 
J902. In the notice of proposed rulemaking, 
paragraph S4.2 incorporated, with minor modi- 
fications, the defrosted area and defrosting time 
requirements of Recommended Practice J902. 
Comparison of the two versions of the SAE 
Recommended Practice reveals that there are 
great differences between the areas and times 



PART 571; S 103— PRE 1 



Eff«<tiv*: January 1, 1969 



prescribed by J902 and those prescribed by 
J902a. The requests for a change in paragraph 
S4.2 acknowledged that compliance with one pro- 
cedure is not necessarily more difficult than com- 
pliance with the other. The submissions did not 
indicate that adherence to the J902 requirements 
would impose any significant burden or would 
be impracticable in any sense. In view of the 
absence of sufficient substantiation to justify 
changing the standard, paragraph S4.2 has not 
been modified to allow alternative defrosted area 
and defrosting time requirements. 

One comment requested that the standard be 
changed to allow 5 minutes more to meet the 
defrosted area requirements of the critic^il or "C" 
area. It was said that reasonable performance 
tolerances should be taken into account, and that, 
therefore, the requirement of paragraph 3.1 of 
SAE Recommended Practice J902, as adopted 
in modified form in paragraph S4.2 of the stand- 
ard, that the "C" area must be 80 percent de- 
frosted after 20 minutes of operation should be 
changed to allow manufacturers 25 minutes to 
attain the 80 percent defrosted goal. Such a 
modification would permit a significant reduc- 
tion of the defrosting performance of defrosting 
and defogging systems and this, in turn, would 
be contrary to the interest of safety. While it 
is true that variations in such things as the per- 
formance of the thermostat and the outlet nozzle 
will affect the system's capability to defrost a 
given windshield area within a stated time, there 



is no apparent reason why it is impracticable to 
design and construct the system so that, at a 
minimum performance level, it will comply with 
the requirements of paragraph S4.2. For these 
reasons, the Administrator has rejected this re- 
quest for modification of the standard. 

Many conunents submitted suggestions that 
went beyond the scope of the notice. For ex- 
ample, submissions that discussed the problems 
of establishing performance requirements for de- 
frosting and defogging systems on multipur- 
pose passenger vehicles, trucks, and buses were 
received. These, and other comments of this 
nature, will be considered in connection with 
future rulemaking action. 

In consideration of the foregoing, § 371.21 of 
Part 371, Federal Motor Vehicle Safety Stand- 
ards, is amended, effective January 1, 1969, by 
amending Motor Vehicle Safety Standard No. 
103 

This amendment is made under the authority 
of sections 103 and 119 of the National Traffic 
and Motor Vehicle Safety Act of 1966 (15 U.S.C. 
1392, 1407) and the delegation of authority of 
April 24, 1968. 

Issued in Washington, D. C. on April 24, 1968. 

Lowell K. Bridwell, 

Federal Highway Administrator. 

33 F.R. 6468 
April 27, 1968 



PART 571; S 103— PRE 2 



Eff«cHv«: Septambar I, 197S 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 103 

Windshield Defrosting and Defogging Systems 

(Docket No. 73-6; Notice 2) 



The purpose of this notice is to amend Motor 
Vehicle Safety Standard No. 103, Windshield 
Defrosting and Defogging Systems, to revise the 
wind test condition. 

On March 20, 1973, the National Highway 
Traffic Safety Administration published a notice 
(38 F.R. 7339) proposing a change in the stand- 
ard's wind velocity test condition which would 
clarify the NHTSA's intent that the perform- 
ance requirements be met at all levels within the 
specified wind speed range. The present provi- 
sion specifying that "the wind velocity may not 
exceed 5 mph" may be interpreted by manufac- 
turers as requiring compliance at only one point 
within the range. Such an interpretation could 
result in enforcement problems if the NHTSA 
discovered a failure to comply when testing a 
vehicle at one point within the range while the 
manufacturer had attained compliance during 
testing at another point within the specified wind 
speed range. Perpetuation of this type of en- 
forcement situation might retard the develop- 
ment of complying vehicle systems and under- 
mine the level of performance the NHTSA 
intends to accomplish. Therefore, the NHTSA 
proposed in its March 20, 1973, notice that the 
standard specify that the wind velocity test con- 
dition be at any level from to 2 mph. Reading 
this requirement together with the interpretive 
provisions of § 571.4, the vehicle would be re- 
quired to be capable of complying with the 
standard when the wind velocity is at any speed 
within that range. This would prevent any dis- 
crepancy between the manufacturers' and the 
NHTSA's conception of what the standard 
actually requires. 



Several comments submitted in response to the 
proposal to revise the wind speed test condition 
asserted that wind speeds cannot be accurately 
measured below 2 mph, and therefore the require- 
ment should remain unchanged. This objection 
lacks merit, since the standard only requires that 
a vehicle be capable of complying with the stand- 
ard at wind speeds from to 2 mph. A manu- 
facturer may generally conduct his testing at 
higher wind speeds to determine compliance, 
since the greater the wind speed, the more diffi- 
cult it is to defrost the windsliield within the 
specified time span. 

The March 20, 1973, notice also proposed that 
the test chamber temperature sensor be located 
in a position not substantially affected by the 
heat from the engine. Comments from Ford and 
Greneral Motors, submitted in response to this 
aspect of the proposal, objected to the proposed 
temperature location as unobjective and ambig- 
uous and suggested establishment of a more 
specific location. The NHTSA is in tentative 
agreement with commenters' suggestion and is 
proposing in a separate notice issued today an 
exact location for the temperature sensor. 

In consideration of the foregoing, in S4.3 of 
49 CFR § 571.103, Motor Vehicle Safety Stand- 
ard No. 103, paragraph (g) is amended. . . . 

Effective date: September 1, 1975. 

(Sees. 103, 119, Pub. L. 89-563, 80 Stat. 718, 
15 U.S.C. 1392, 1407; delegation of authority 
at 49 CFR 1.51.) 

Issued on March 17, 1975. 

James B. Gregory 
Administrator 

40 F.R. 12991 
March 24, 1975 



PART 571; S 103— PRE 3-4 



EffMllv*: Scptambar 1, 1975 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 
Windshield Defrosting and Defogging Systems 
(Docket No. 73-6; Notico 2) 



103 



The purpose of this notice is to amend Motor 
Vehicle Safety Standard No. 103, Windshield 
Defrosting and Defogging Systems, to revise the 
wind test condition. 

On March 20, 1973, the National Highway 
TraflSc Safety Administration published a notice 
(38 F.R. 7339) proposing a change in the stand- 
ard's wind velocity test condition which would 
clarify the NHTSA's intent that the perform- 
ance requirements be met at all levels within the 
specified wind speed range. The present provi- 
sion specifying that "the wind velocity may not 
exceed 5 mph" may be interpreted by manufac- 
turers as requiring compliance at only one point 
within the range. Such an interpretation could 
result in enforcement problems if the NHTSA 
discovered a failure to comply when testing a 
vehicle at one point within the range while the 
manufacturer had attained compliance during 
testing at another point within the specified wind 
speed range. Perpetuation of this type of en- 
forcement situation might retard the develop- 
ment of complying vehicle systems and under- 
mine the level of performance the NHTSA 
intends to accomplish. Therefore, the NHTSA 
proposed in its March 20, 1973, notice that the 
standard specify that the wind velocity test con- 
dition be at any level from to 2 mph. Reading 
this requirement together with the interpretive 
provisions of § 571.4, the vehicle would be re- 
quired to be capable of complying with the 
standard when the wind velocity is at any speed 
within tha* range. This would prevent any dis- 
crepancy between the manufacturers' and the 
NHTSA's conception of what the standard 
actually requires. 



Several comments submitted in response to the 
proposal to revise the wind speed test condition 
asserted that wind speeds cannot be accurately 
measured below 2 mph, and therefore the require- 
ment should remain unchanged. This objection 
lacks merit, since the standard only requires that 
a vehicle be capable of complying with the stand- 
ard at wind speeds from to 2 mph. A manu- 
facturer may generally conduct his testing at 
higher wind speeds to determine compliance, 
since the greater the wind speed, the more diffi- 
cult it is to defrost the windsliield within the 
specified time span. 

The March 20, 1973, notice also proposed that 
the test chamber temperature sensor be located 
in a position not substantially affected by the 
heat from the engine. Comments from Ford and 
General Motors, submitted in response to this 
aspect of the proposal, objected to the proposed 
temperature location as unobjective and ambig- 
uous and suggested establishment of a more 
specific location. The NHTSA is in tentative 
agreement with commenters' suggestion and is 
proposing in a separate notice issued today an 
exact location for the temperature sensor. 

In consideration of the foregoing, in S4.3 of 
49 CFR § 571.103, Motor Vehicle Safety Stand- 
ard No. 103, paragraph (g) is amended. . . • 

Effective date : September 1, 1975. 

(Sees. 103, 119, Pub. L. 89-563, 80 Stat. 718, 
15 U.S.C. 1392, 1407; delegation of authority 
at 49 CFR 1.51.) 



Issued on March 17, 1975. 



James B. Gregory 
Administrator 

40 F.R. 12991 
March 24, 1975 



PART 571; S 103— PRE 3-4 



1, 1*7S 



PREAMBLE TO AMB40MENT TO MOTOR VEHiaE SAFETY STANDARD NO. 103 

Windshield Defrosting and Defogging Systems 
(Docket No. 73-6; Notice 4) 



The purpose of this notice is to amend Motor 
Vehicle Safety Standard No. 103, Windshield 
Defrosting and Defogging Systems, 49 CFR 
571.103, to specify a relocation of the test cham- 
ber temperature and wind velocity sensors. 

On llkfarch 24, 1975, the National Highway 
Traffic Safety Administration published a notice 
(40 F.R. 13002) proposing a change in the loca- 
tion of the test chamber temperature and wind 
velocity sensors to a position where they would 
not be affected by air released from vehicle en- 
gines during testing. A petition from Jaguar 
Cars Division of British Leyland UK Limited, 
describing compliance problems for vehicles that 
direct engine heat at the windshield as part of 
the defrosting process, prompted the rulemaking 
action. 

It was proposed that the temperature and 
wind sensors be positioned at the forwardmost 
point of the vehicle or 36 inches from the base 
of the windshield, whichever is farther forward, 
at a level halfway between top and bottom of the 
windshield. At tiiis location, the NHTSA con- 
cluded that the temperature measurement would 
not be affected by expelled engine heat and the 
wind measurement would not be affected by air 
released from hood ducts. 

Comments to the proposal were received from 
Chrysler, Jaguar, and General Motors. Both 
Chrysler and General Motors supported adop- 
tion of the amendment. 



Jaguar took issue with the proposed thermo- 
couple location and asked that the sensors be 
placed 3 feet forward of the vehicle. The 
NHTSA denies this request, having found that 
the proposed thermocouple position provides for 
reliable and objective temperature and wind ve- 
locity measurements. Location of the sensors at 
the position suggested by Jaguar is therefore 
unnecessary and would tend to penalize those 
manufacturers using short cold chambers for 
compliance testing. The purpose of the amend- 
ment is to relocate the temperature and wind 
sensors to locations where they will not be af- 
fected by air released from vehicle engines. The 
agency concludes that the proposed location ac- 
complishes this goal and should therefore be 
adopted. 

In consideration of the foregoing, Standard 
No. 103 (49 CFR 571.103) is amended by adding 
in S4.3 a new paragraph (h) 

Effective date : September 1, 1975. 

(Sees. 103, 119, Pub. L. 89-563, 80 Stat. 718, 
15 U.S.C. 1392, 1407; delegation of authority at 
49 CFR 1.51.) 

Issued on July 28, 1975. 

James B. Gregory 
Administrator 

40 F.R. 32336 
August 1, 1975 



PART 571; S 103— PRE 5-6 



Efbctiv*: S«pl«mb«r 1, 1975 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 103 

Windshisld Defrosting and Defogging Systems 
(Docket No. 73-6; Notice 4) 



The purpose of this notice is to amend Motor 
Vehicle Safety Standard No. 103, Windshield 
Defrosting and Defogging Systems, 49 CFR 
571.103, to specify a relocation of the test cham- 
ber temperature and wind velocity sensors. 

On March 24, 1975, the National Highway 
Traffic Safety Administration published a notice 
(40 F.R. 13002) proposing a change in the loca- 
tion of the test chamber temperature and wind 
velocity sensors to a position where they would 
not be affected by air released from vehicle en- 
gines during testing. A petition from Jaguar 
Cars Division of British Leyland UK Limited, 
describing compliance problems for vehicles that 
direct engine heat at the windshield as part of 
the defrosting process, prompted the rulemaking 
action. 

It was proposed that the temperature and 
wind sensors be positioned at the forwardmost 
point of the vehicle or 36 inches from the base 
of the windshield, whichever is farther forward, 
at a level halfway between top and bottom of the 
windshield. At this location, the NHTSA con- 
cluded that the temperature measurement would 
not be affected by expelled engine heat and the 
wind measurement would not be affected by air 
released from hood ducts. 

Comments to the proposal were received from 
Chrysler, Jaguar, and General Motors. Both 
Chrysler and General Motors supported adop- 
tion of the amendment. 



Jaguar took issue with the proposed thermo- 
couple location and asked that the sensors be 
placed 3 feet forward of the vehicle. The 
NHTSA denies this request, having found that 
the proposed thermocouple position provides for 
reliable and objective temperature and wind ve- 
locity measurements. Location of the sensors at 
the position suggested by Jaguar is therefore 
unnecessary and would tend to penalize those 
manufacturers using short cold chambers for 
compliance testing. The purpose of the amend- 
ment is to relocate the temperature and wind 
sensors to locations where they will not be af- 
fected by air released from vehicle engines. The 
agency concludes that the proposed location ac- 
complishes this goal and should therefore be 
adopted. 

In consideration of the foregoing, Standard 
No. 103 (49 CFR 571.103) is amended by adding 
in S4.3 a new paragraph (h). . . . 

Effective date: September 1, 1975. 

(Sees. 103, 119, Pub. L. 89-563, 80 Stat. 718, 
15 U.S.C. 1392, 1407; delegation of authority at 
49 CFR 1.51.) 

Issued on July 28, 1975. 

James B. Gregory 
Administrator 

40 F.R. 32336 
August 1, 1975 



PART 571; S 103— PRE 5-6 



MOTOR VEHICLE SAFETY STANDARD NO. 103 

Windshield Defrosting and Defogging Systems— Passenger Cars, Multipurpose 
Passenger Vehicles, Trucks, and Buses 



51. Scope. This standard specifies require- 
ments for windshield defrosting and defogging 
systems. 

52. Application. This standard applies to pas- 
senger cars, multipurpose passenger vehicles, 
trucks, and buses, manufactured for sale in the 
Continental United States. 

53. Definitions. "Road load" means the power 
output required to move a given motor vehicle 
at curb weight plus 400 pounds on level, clean, 
dry, smooth Portland cement concrete pavement 
(or other surface with equivalent coefficient of 
surface friction) at a specified speed through still 
air at 68°F and standard barometric pressure 
(29.92" of Hg.) and includes driveline friction, 
rolling friction, and air resistance. 

54. Requirements. 

54.1 Each vehicle shall have a windshield de- 
frosting and defogging system. 

54.2 Each passenger car windshield defrost- 
ing and defogging system shall meet the re- 
quirements of section 3 of SAE Recommended 
Practice J902, "Passenger Car Windshield De- 
frosting Systems," August 1964, when tested in 
accordance with S4.3, except that "the critical 
area" specified in paragraph 3.1 of SAE Recom- 
mended Practice J902 shall be that established 
as Area C in accordance with Motor Vehicle 
Safety Standard No. 104, "Windshield Wiping 
and Washing Systems," and "the entire wind- 
shield" specified in paragraph 3.3 of SAE Recom- 
mended Practice J902 shall be that established 
as Area A in accordance with Motor Vehicle 
Safety Standard No. 104. 

54.3 Demonstration procedure. The passenger 
car windshield defrosting and defogging system 
shall be tested in accordance with the portions of 
paragraphs 4.1 through 4.4.7 of SAE Recom- 



mended Practice J902, August 1964, or SAE 
Recommended Practice J902a, March 1967, ap- 
plicable to that system, except that— 

(a) During the first five minutes of the test, 
the engine speed or speeds may be those which 
the manufacturer recommends as the warm-up 
procedure for cold weather starting; 

(b) During the last 35 minutes of the test 
period (or the entire test period if the five-minute 
warm-up procedure is not used), either— 

(i) The engine speed shall not exceed 1500 
rpm in neutral gear; or 

(ii) The engine speed and load shall not ex- 
ceed the speed and load at 25 mph in the manu- 
facturer's recommended gear with road load; 

(c) A room air change of 90 times per hour is 
not required; 

(d) The windshield wipers may be used dur- 
ing the test if they are operated without manual 
assist; 

(e) One or two windows may be open a total 
of one inch; 

(f) The defroster blower may be turned on at 
any time; and 

(g) The wind velocity is at any level from 
to 2 mph. 

(h) The test chamber temperature and the 
wind velocity shall be measured, after the engine 
has been started, at the forwardmost point of 
the vehicle or a point 36 inches from the base of 
the windshield, whichever is farther forward, at 
a level halfway between the top and bottom of 
the windshield on the vehicle centerline. 



33 F.R. 6469 
Aprii 27,1968 



PART 571; S 103-1 



^b 



MOTOR VEHICLE SAFETY STANDARD NO. 103 

Windshield Defrosting and Defogging Systems— Passenger Cars, Multipurpose 
Passenger Vehicles, Trucks, and Buses 



51. Scope. This standard specifies require- 
ments for windshield defrosting and defogging 
systems. 

52. Application. This standard applies to pas- 
senger cars, multipurpose passenger vehicles, 
trucks, and buses, manufactured for sale in the 
Continental United States. 

53. Definitions. "Road load" means the power 
output required to move a given motor vehicle 
at curb weight plus 400 pounds on level, clean, 
dry, smooth Portland cement concrete pavement 
(or other surface with equivalent coefficient of 
surface friction) at a specified speed through still 
air at 68°F and standard barometric pressure 
(29.92" of Hg.) and includes driveline friction, 
rolling friction, and air resistance. 

54. Requirements. 

54.1 Each vehicle shall have a windshield de- 
frosting and defogging system. 

54.2 Each passenger car windshield defrost- 
ing and defogging system shall meet the re- 
quirements of section 3 of SAE Recommended 
Practice J902, "Passenger Car Windshield De- 
frosting Systems," August 1964, when tested in 
accordance with S4.3, except that "the critical 
area" specified in paragraph 3.1 of SAE Recom- 
mended Practice J902 shall be that established 
as Area C in accordance with Motor Vehicle 
Safety Standard No. 104, "Windshield Wiping 
and Washing Systems," and "the entire wind- 
shield" specified in paragraph 3.3 of SAE Recom- 
mended Practice J902 shall be that established 
as Area A in accordance with Motor Vehicle 
Safety Standard No. 104. 

54.3 Demonstration procedure. The passenger 
car windshield defrosting and defogging system 
shall be tested in accordance with the portions of 
paragraphs 4.1 through 4.4.7 of SAE Recom- 



mended Practice J902, August 1964, or SAE 
Recommended Practice J902a, March 1967, ap- 
plicable to that system, except that— 

(a) During the first five minutes of the test, 
the engine speed or speeds may be those which 
the manufacturer recommends as the warm-up 
procedure for cold weather starting; 

(b) During the last 35 minutes of the test 
period (or the entire test period if the five-minute 
warm-up procedure is not used), either— 

(i) The engine speed shall not exceed 1500 
rpm in neutral gear; or 

(ii) The engine speed and load shall not ex- 
ceed the speed and load at 25 mph in the manu- 
facturer's recommended gear with road load; 

(c) A room air change of 90 times per hour is 
not required; 

(d) The windshield wipers may be used dur- 
ing the test if they are operated without manual 
assist; 

(e) One or two windows may be open a total 
of one inch; 

(f) The defroster blower may be turned on at 
any time; and 

(g) The wind velocity is at any level from 
to 2 mph. 

(h) The test chamber temperature and the 
wind velocity shall be measured, after the engine 
has been started, at the forwardmost point of 
the vehicle or a point 36 inches from the base of 
the windshield, whichever is farther forward, at 
a level halfway between the top and bottom of 
the windshield on the vehicle centerline. 



33 F.R. 6469 
April 27,1968 



I 



PART 571; S 103-1 



Ellacflv*: Jonuaiy 1, 1969 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 104 

Windshield Wiping and Washing Systems — Passenger Cars, Multipurpose 
Passenger Vehicles, Trucks, and Buses 

(Docket No. 7) 



Motor Vehicle Safety Standard No. 104 (32 
F.R. 2410) specifies requirements for windshield 
wiping and washing systems for passenger cars 
68 or more inches in overall width. A proposal 
to amend section 371.21 of Part 371, Federal 
Motor Vehicle Safety Standards, by amending 
Standard No. 104 was published in the Federal 
Register on December 28, 1967 (32 F.R. 20867). 

Interested persons have been afforded an oppor- 
tunity to participate in the making of the amend- 
ment. Their comments, as well as other avail- 
able information, have been carefully considered. 

The primary purpose of the amendment is to 
broaden the application of the Initial Standard 
to cover smaller passenger cars, multipurpose pas- 
senger vehicles, trucks, and buses. The wiped- 
area performance requirements have been ex- 
tended to cars smaller than 68 inches wide, and 
tables which prescribe the minimum size of wiped 
areas have been added for such cars. The 
overall effect is that the wiper systems of various 
passenger cars must wipe areas to provide ap- 
proximately equivalent driver vision. The wiper 
frequency requirement, modified to prescribe that 
the highest and lowest frequencies must differ by 
at least 15 cycles per minute, has been extended 
to multipurpose passenger vehicles, trucks, and 
buses. A requirement for a windshield washing 
system has also been extended to smaller cars, 
multipurpose passenger vehicles, trucks, and 
buses. Other modifications to the standard were 
made in order to improve its clarity. 

The material received in response to the notice 
of proposed rulemaking evinced almost universal 
acknowledgement that broadening of the cover- 
age of the standard wotUd improve overall driver 
visibility and thus contribute to safety on the 
highways. With a few minor exceptions, dis- 



cussed below, there was no suggestion that manu- 
facturers would have any difficulty in complying 
with the revised requirements by the January 
1, 1969, effective date. 

Some of the comments indicated some misim- 
derstanding of the reference to SAE Recom- 
mended Practice J903a, "Passenger Car Wind- 
shield Wiper Systems," May 1966, in paragraph 
S4.1.2 of the standard. Paragraph S4.1.2 is part 
of the wiped area requirement and it provides, 
among other things, for testing "in accordance 
with" SAE Recommended Practice J903a. This 
does not mean that all of section 4, "Test Meth- 
ods," of SAE Recommended Practice J903a is 
incorporated by reference into the wiped area 
requirements of the standard. The reference to 
the SAE Recommended Practice relates only to 
its procedure for testing wiper systems for com- 
pliance with wiped area requirements. Therefore, 
the ozone test, wiper system stall test, 1,500,000- 
cycle durability test, and other details of section 
4 of SAE Recommended Practice J903a are not 
included in the scope of Standard No. 104. 

Several comments asked that the standard con- 
tain a demonstration procedure for testing wind- 
shield wiper systems for compliance with the 
45-<5ycle-per-minute frequency requirement and 
the 15-cycle-per-minute frequency differential re- 
quirement. Apparently, these persons were con- 
cerned that the ability of systems to meet both 
requirements might be judged under abnormal 
conditions rather than under those encountered 
in normal driving. Considering these requests 
reasonable, the Administrator has provided that 
windshield wiper systems will be deemed to have 
met the frequency differential requirements of the 
standard (sections S4.1.2 and S4.1.1.3) if they 
meet those requirements when tested in accor- 



\ 



PART 571; S 104^PRE 1 



Mvctiva: January 1, 1969 



dance with sections 4.1.1 and 4.1.2 of SAE Rec- 
ommended Practice J903a. 

One comment requested clarification of the lo- 
cation of the plan view reference line in the 
"eyellipse." The "eyellipse" is the "95 percent 
eye range contour" specified in SAE Recom- 
mended Practice J941, "Passenger Car Driver's 
Eye Range," November 1965. The author of this 
comment pointed out that Figure 2 in Recom- 
mended Practice J903a incorrectly shows the plan 
view reference line as located through the geo- 
metric center of the 95 percent eye range con- 
tour. The drawings referred to in Recommended 
Practice J941 show the "eyellipse" centerline as 
disecting the left ellipse of the two intersecting 
ellipses in the plan view. In paragraph S3 of the 
standard, the definition of the "95 percent eye 
range contour" makes reference to SAE Recom- 
mended Practice J941, which correctly positions 
the plan view reference line in the left-hand 
ellipse of the "eyellipse." Accordingly, the Ad- 
ministrator has determined that subparagraph 
(a) of the definition of "plan view reference line" 
in paragraph S3 of the standard correctly reflects 
this position as defined, but subparagraph (b) 
of the same definition has been modified to 
clarify the location of the "eyellipse." Sub- 
paragraph (b), as revised by this amendment, 
places the plan view reference line outboard of 
the longitudinal centerline of the driver's desig- 
nated seating position, thus locating the "eyel- 
lipse" itself geometrically in the center of the 
seat. 

In the notice of proposed rulemaking, para- 
graph S4.2 required a windshield washing system 
meeting the requirements of SAE Recommended 
Practice J942, "Passenger Car Windshield 
Washer Systems," November 1965. Section 3.1 of 
that Recommended Practice sets washer system 
capability requirements by reference to the pas- 
senger car wiped area requirements of SAE Rec- 
ommended Practice J903. Several comments 
pointed this out and requested modification of 
the standard in view of the fact that the wiped 
area requirements of the standard are different 
from those of Recommended Practice J903. In 
addition, some comments sought revision of this 
particular provision on the ground that the wiped 
areas of Recommended Practice J903 were created 
for passenger cars, while the washer provisions 

PART 571; 



of the standard apply to multipurpose passenger 
vehicles, trucks, and buses as well. In view of 
these comments, the Administrator has deleted the 
cross-reference, and S4.2 of the standard has 
been modified. The passenger car wiped-area re- 
quirement is now defined as that established 
under paragraph S4.1.2.1 of the standard; the 
wiped area for multipurpose passenger vehicles, 
trucks, and buses is now defined as the wiped 
area pattern designed by the manufacturer for 
the windshield wiping system on the exterior of 
the windshield glazing. 

One comment sought a change in the wiper 
frequency differential requirement from 16 cycles 
per minute to 10 cycles per minute, claiming that 
production tolerances did not permit exact com- 
pliance with the 15-cycle-per-minute differential 
requirement. The comment did not indicate why, 
assuming a 5-cycle-per-minute tolerance is 
needed, the system could not be constructed to 
operate in the frequency differential range of be- 
tween 15 and 20 cycles per minute rather than a 
10-15 cycle range. The standard, like all stand- 
ards, is a minimum one, and nothing in it pro- 
hibits a higher standard of performance than the i 
one specified as minimal. For these reasons, and \ 
because the deviation requested would, if granted, 
lower the safety performance of this segment of 
the standard, the request has been denied. 

Similarly, the Administrator has denied a re- 
quest for deletion of the requirement that wind- 
shield washing systems must, when tested, deliver 
approximately 15 cc. of fluid to the windshield 
glazing surface. The requirement is embodied 
in section 2.11 of SAE Recommended Practice 
J942, which is incorporated by reference in para- 
graph 4.2 of the standard. The amount of fluid 
placed on the windshield's exterior is a central 
performance characteristic of a washing system, 
and a decrease in the required amount would 
clearly diminish the capability of the system to 
promote safety. Neither the comments in gen- 
eral nor any other known data indicate that the 
requirement incorporated in the standard is un- 
feasible. The one comment that sought a change 
in this aspect of the standard contained no detail 
demonstrating that systems in current production 
would be unable to meet the requirement by the 
effective date of the amendment. Consequently, 
the Administrator has decided not to deviate ^ 

S 104— PRE 2 



EffMNva: Jonuaiy I, 194* 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 104 

Windshield Wiping and Washing Systems — Passenger Cars, Multipurpose 
Passenger Vehicles, Trucks, and Buses 

(Docket No. 7) 



Motor Vehicle Safety Standard No. 104 (32 
F.R. 2410) specifies requirements for windshield 
wiping and washing systems for passenger cars 
68 or more inches in overall width. A proposal 
to amend section 371.21 of Part 371, Federal 
Motor Vehicle Safety Standards, by amending 
Standard No. 104 was published in the Federal 
Register on December 28, 1967 (32 F.R. 20867). 

Interested persons have been afforded an oppor- 
tunity to participate in the making of the amend- 
ment. Their comments, as well as other avail- 
able information, have been carefully considered. 

The primary purpose of the amendment is to 
broaden the application of the Initial Standard 
to cover smaller passenger cars, multipurpose pas- 
senger vehicles, trucks, and buses. The wiped- 
area performance requirements have been ex- 
tended to cars smaller than 68 inches wide, and 
tables which prescribe the minimum size of wiped 
areas have been added for such cars. The 
overall effect is that the wiper systems of various 
passenger cars must wipe areas to provide ap- 
proximately equivalent driver vision. The wiper 
frequency requirement, modified to prescribe that 
the highest and lowest frequencies must differ by 
at least 15 cycles per minute, has been extended 
to multipurpose passenger vehicles, trucks, and 
buses. A requirement for a windshield washing 
system has also been extended to smaller cars, 
multipurpose passenger vehicles, trucks, and 
buses. Other modifications to the standard were 
made in order to improve its clarity. 

The material received in response to the notice 
of proposed rulemaking evinced almost universal 
acknowledgement that broadening of the cover- 
age of the standard would improve overall driver 
visibility and thus contribute to safety on the 
highways. With a few minor exceptions, dis- 



cussed below, there was no suggestion that manu- 
facturers would have any difficulty in complying 
with the revised requirements by the January 
1, 1969, effective date. 

Some of the comments indicated some misun- 
derstanding of the reference to SAE Recom- 
mended Practice J903a, "Passenger Car Wind- 
shield Wiper Systems," May 1966, in paragraph 
S4.1.2 of the standard. Paragraph S4.1.2 is part 
of the wiped area requirement and it provides, 
among other things, for testing "in accordance 
with" SAE Recommended Practice J903a. This 
does not mean that all of section 4, "Test Meth- 
ods," of SAE Recommended Practice J903a is 
incorporated by reference into the wiped area 
requirements of the standard. The reference to 
the SAE Recommended Practice relates only to 
its procedure for testing wiper systems for com- 
pliance with wiped area requirements. Therefore, 
the ozone test, wiper system stall test, 1,500,000- 
cycle durability test, and other drtails of section 
4 of SAE Recommended Practice J903a are not 
included in the scope of Standard No. 104. 

Several comments asked that the standard con- 
tain a demonstration procedure for testing wind- 
shield wiper systems for compliance with the 
45-cycle-per-minute frequency requirement and 
the 15-cycle-per-minute frequency differential re- 
quirement. Apparently, these persons were con- 
cerned that the ability of systems to meet both 
requirements might be judged under abnormal 
conditions rather than under those encountered 
in normal driving. Considering these requests 
reasonable, the Administrator has provided that 
windshield wiper systems will be deemed to have 
met the frequency differential requirements of the 
standard (sections S4.1.2 and S4.1.1.3) if they 
meet those requirements when tested in accor- 



PAUT 571; S 104— PRE 1 



Mm«v«: January 1, 1969 



dance with sections 4.1.1 and 4.1.2 of SAE Rec- 
ommended Practice J903a. 

One comment requested clarification of the lo- 
cation of the plan view reference line in the 
"eyellipse." The "eyellipse" is the "95 percent 
eye range contour" specified in SAE Recom- 
mended Practice J941, "Passenger Car Driver's 
Eye Range," November 1965. The author of this 
comment pointed out that figure 2 in Recom- 
mended Practice J903a incorrectly shows the plan 
view reference line as located through the geo- 
metric center of the 95 percent eye range con- 
tour. The drawings referred to in Recommended 
Practice J941 show the "eyellipse" centerline as 
disecting the left ellipse of the two intersecting 
ellipses in the plan view. In paragraph S3 of the 
standard, the definition of the "95 percent eye 
range contour" makes reference to SAE Recom- 
mended Practice J941, which correctly positions 
the plan view reference line in the left-hand 
ellipse of the "eyellipse." Accordingly, the Ad- 
ministrator has determined that subparagraph 
(a) of the definition of "plan view reference line" 
in paragraph S3 of the standard correctly reflects 
this position as defined, but subparagraph (b) 
of the same definition has been modified to 
clarify the location of the "eyellipse." Sub- 
paragraph (b), as revised by this amendment, 
places the plan view reference line outboard of 
the longitudinal centerline of the driver's desig- 
nated seating position, thus locating the "eyel- 
lipse" itself geometrically in the center of the 
seat. 

In the notice of proposed rulemaking, para- 
graph S4.2 required a windshield washing system 
meeting the requirements of SAE Recommended 
Practice J942, "Passenger Car Windshield 
Washer Systems," November 1965. Section 3.1 of 
that Recommended Practice sets washer system 
capability requirements by reference to the pas- 
senger car wiped area requirements of SAE Rec- 
ommended Practice J903. Several comments 
pointed this out and requested modification of 
the standard in view of the fact that the wiped 
area requirements of the standard are different 
from those of Recommended Practice J903. In 
addition, some comments sought revision of this 
particular provision on the ground that the wiped 
areas of Recommended Practice J903 were created 
for passenger cars, while the washer provisions 



of the standard apply to multipurpose passenger 
vehicles, trucks, and buses as well. In view of 
these comments, the Administrator has deleted the 
cross-reference, and S4.2 of the standard has 
been modified. The passenger car wiped-area re- 
quirement is now defined as that established 
under paragraph S4.1.2.1 of the standard; the 
wiped area for multipurpose passenger vehicles, 
trucks, and buses is now defined as the wiped 
area pattern designed by the manufacturer for 
the windshield wiping system on the exterior of 
the windshield glazing. 

One comment sought a change in the wiper 
frequency differential requirement from 16 cycles 
per minute to 10 cycles per minut«, claiming that 
production tolerances did not permit exact com- 
pliance with the 15-cycle-per-minute differentia! 
requirement. The comment did not indicate why, 
assuming a 5-cycle-per-minute tolerance is 
needed, the system could not be constructed to 
operate in the frequency differential range of be- 
tween 15 and 20 cycles per minute rather than a 
10-15 cycle range. The standard, like all stand- 
ards, is a minimum one, and nothing in it pro- 
hibits a higher standard of performance than the / 
one specified as minimal. For these reasons, and (^ 
because the deviation requested would, if granted, 
lower the safety performance of this segment of 
the standard, the request has been denied. 

Similarly, the Administrator has denied a re- 
quest for deletion of the requirement that wind- 
shield washing systems must, when tested, deliver 
approximately 15 cc. of fluid to the windshield 
glazing surface. The requirement is embodied 
in section 2.11 of SAE Recommended Practice 
J942, which is incorporated by reference in para- 
graph 4.2 of the standard. The amount of fluid 
placed on the windshield's exterior is a central 
performance characteristic of a washing system, 
and a decrease in the required amount would 
clearly diminish the capability of the system to 
promote safety. Neither the comments in gen- 
eral nor any other known data indicate that the 
requirement incorporated in the standard is un- 
feasible. The one comment that sought a change 
in this aspect of the standard contained no detail 
demonstrating that systems in current production 
would be unable to meet the requirement by the 
effective date of the amendment. Consequently, 
the Administrator has decided not to deviate / 



PART 571; S 104^PRE 2 



IffacHva: Januoiy 1, 19M 



from the adoption of section 2.11 of Recom- 
mended Practice J942, as announced in the notice 
of proposed rulemaking. 

Several comments pointed out the difficulties 
involved in prescribing wiped-area requirements 
for multipurpose passenger vehicles, trucks, and 
buses. The Administrator is cognizant of the 
problems that arise because of the wide variety 
of windshield sizes and configurations as well as 
the differing relationships between the drivers' 
positions and the windshields in these vehicles. 
Owing to these factors, he has concluded that it 
is not possible to prescribe uniform wiped areas 
for the wiper systems of these vehicles generally 
or for vehicles within any generic type at this 
time. Hence, the standard's minimum wiped- 
area requirements apply only to passenger cars. 
The possibility of prescribing such requirements 
for other vehicular types will continue to be 
studied. 

In addition, the Administration will also study 
the question of whether there should be standards 
applicable to so-called "hidden" windshield wipers 



to insure their operability under snow and ice 
conditions. Although a number of comments 
sought the inclusion of such a provision in this 
standard, it was deemed inadvisable to do so 
in view of the absence of any such provision from 
the notice of proposed rulemaking. 

In consideration of the foregoing, § 371.21 of 
Part 371, Federal Motor Vehicle Safety Stand- 
ards, is amended effective January 1, 1969, by 
amending Motor Vehicle Safety Standard No. 
104 

This amendment is made under the authority 
of sections 103 and 119 of the National Traffic 
and Motor Vehicle Safety Act of 1966 (15 U.S.C. 
1392, 1407) and the delegation of authority of 
April 24, 1968. 

Issued in Washington, D.C., on April 24, 1968. 

Lowell K. Bridwell 

Federal Highway Administrator. 

33 F.R. 6466 
April 27, 1968 



PAUT 571 ; S 104— PRE a-4 



i 



f 



ElhcHv*: January 1, 19<9 



from the adoption of section 2.11 of Recom- 
mended Practice J942, as announced in the notice 
of proposed rulemaking. 

Several comments pointed out the difficulties 
involved in prescribing wiped-area requirements 
for multipurpose passenger vehicles, trucks, and 
buses. The Administrator is cognizant of the 
problems that arise because of the wide variety 
of windshield sizes and configurations as well as 
the differing relationships between the drivers' 
positions and the windshields in these vehicles. 
Owing to these factors, he has concluded that it 
is not possible to prescribe uniform wiped areas 
for the wiper systems of these vehicles generally 
or for vehicles within any generic type at this 
time. Hence, the standard's minimum wiped- 
area requirements apply only to passenger cars. 
The possibility of prescribing such requirements 
for other vehicular types will continue to be 
studied. 

In addition, the Administration will also study 
the question of whether there should be standards 
applicable to so-called "hidden" windshield wipers 



to insure their operability under snow and ice 
conditions. Although a number of comments 
sought the inclusion of such a provision in this 
standard, it was deemed inadvisable to do so 
in view of the absence of any such provision from 
the notice of proposed rulemaking. 

In consideration of the foregoing, § 371.21 of 
Part 371, Federal Motor Vehicle Safety Stand- 
ards, is amended effective January 1, 1969, by 
amending Motor Vehicle Safety Standard No. 
104 

This amendment is made under the authority 
of sections 103 and 119 of the National Traffic 
and Motor Vehicle Safety Act of 1966 (15 U.S.C. 
1392, 1407) and the delegation of authority of 
April 24, 1968. 

Issued in Washington, D.C., on April 24, 1968. 

Lowell K. Bridwell 

Federal Highway Administrator. 

33 F.R. 6466 
April 27, 1968 



\) 



PART 571; S 104^PRE 3-4 



i 



MmMv*i Jonuofy 1, l*6f 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 104 

Windshield Wiping and Washing Systems— Passenger Cars, Multipurpose 

Passenger Vehicles, Trucks, and Buses 

(Docket No. 7) 



An amendment to Motor Vehicle Standard No. 
104, which specifies requirements for windshield 
wiping and washing systems in passenger cars, 
multipurpose passenger vehicles, trucks, and 
buses, was issued on April 24, 1968 (33 F.R. 
6466). The amendment is eflfective January 1, 
1969. 

Paragraph S3 of the amended standard, en- 
titled "Definitions," contains a definition of the 
"plan view reference line" which, as it applies 
to vehicles with individual-type seats, locates the 
line parallel to the vehicle's longitudinal center- 
line so that the 95 percent eye range contour, or 
eyellipse, is geometrically positioned around the 
longitudinal centerline of the driver's designated 
seating position. 

The purpose of the definition, as stated in the 
preamble to the standard, was to position the 
eyellipse geometrically in the center of the seat. 
The Administrator has determined that the defini- 
tion may be construed to permit a different loca- 
tion of the eyellipse, since it provides that the 95 
percent eye range contour must be geometrically 
positioned "around" the longitudinal centerline of 
the driver's seat. Therefore, the definition is 
being amended to clarify the location of the 
eyellipse by requiring its geometric center to be 
positioned on the longitudinal centerline of the 
driver's designated seating position. 

Several petitions for reconsideration of the 
amendment have raised the possibility that the 
definition of plan view reference line may im- 
pose an unintended hardship on manufacturers of 
smaller cars. The effect of the definition is to 
relocate the eyellipse slightly outboard of the 
location prescribed in the standard prior to the 
amendment. This change may make it imprac- 
ticable for manufacturers of smaller cars to com- 



ply with the wiped-area requirements of the 
standard. Therefore, the definition is being 
further amended to permit optional positioning of 
the eyellipse on the plan view reference line in 
the manner prescribed in the standard prior to 
the previous amendment. 

Neither of these revisions appreciably alters 
the amount of the windshield surface which wip- 
ing systems must wipe under the standard. Hence 
the amendments will have no adverse effect on 
motor vehicle safety. 

Paragraph S4.1.1.3 of the amendment provides, 
in part, that the lowest frequency or speed of 
windshield wiping systems must be at least 20 
cycles per minute regardless of engine speed and 
engine load. The Administrator has received 
petitions asking that a frequency or speed lower 
than 20 cycles per minute be allowed. The peti- 
tioners state that such a lower frequency or speed 
will be useful under conditions of very light 
precipitation or wheel spray, and that retention 
of the 20-cycle-per-minute minimum will preclude 
the use of so-called "intermittent" windshield 
wiping systems. The Administrator has con- 
cluded that the standard should be amended to 
allow manufacturers to use systems which can 
operate at a frequency or speed of less than 20 
cycles per minute so long as the driver of the 
vehicle has available a system capable of op- 
erating at at least two other frequencies or speeds, 
differing by at least 15 cycles per minute, the 
lower of which is at least 20 cycles per minute. 
The net effect of this change is to allow as 
many different frequencies or speeds as the manu- 
facturer desires as long as at least two of these 
speeds or frequencies meet the specified require- 
ments. 



PART 671; S 104^PRE 6 



M««tlv«: January 1, 1969 

Since these amendments provide clarification, (Sees. 103, 119, National Traffic and Motor 

relieve a hardship and impose no additional Vehicle Safety Act of 1966 (15 U.S.C. 1392, 

burden on any person, notice and public proce- 1470) ; delegation of authority of April 24, 1968 

dure thereon are unnecessary. (33 F.R. 6538) ). 

In consideration of the foregoing, § 371.21 of j^^^^ ^^ Washington, D.C., on July 31, 1968. 
Part 371, Federal Motor Vehicle Safety Stand- 
ards, Motor Vehicle Safety Standard No. 104 (32 

F.R. 2410), as amended (33 F.R. 6466), is Lowell K. Bnd well, 

amended, effective July 31, 1968. . . . F«<*e™l Highway Administrator. 

It is found, for good cause shown, that an eflfec- 

tive date sooner than 180 days after the issuance 33 F.R. 11117 

of these amendments is in the public interest. August 6, 1968 



PART 571; S 104^PRE 6 



1, 11 



PREAMBLE TO AMENDMENT TO MOTOR VEHiaE SAFETY STANDARD NO. 104 

Windthi«ld Wiping and Washing Systems— Passenger Cars, Multipurpose 

Passenger Vehicles, Trucks, and Buses 

(Docket No. 7) 



An amendment to Motor Vehicle Standard No. 
104, which specifies requirements for windshield 
wiping and washing systems in passenger cars, 
multipurpose passenger vehicles, trucks, and 
buses, was issued on April 24, 1968 (33 F.R. 
6466). The amendment is effective January 1, 
1969. 

Paragraph S3 of the amended standard, en- 
titled "Definitions," contains a definition of the 
"plan view reference line" which, as it applies 
to vehicles with individual-type seats, locates the 
line parallel to the vehicle's longitudinal center- 
line so that the 95 percent eye range contour, or 
eyellipse, is geometrically positioned around the 
longitudinal centerline of the driver's designated 
seating positioiL 

The purpose of the definition, as stated in the 
preamble to the standard, was to position the 
eyellipse geometrically in the center of the seat. 
The Administrator has determined that the defini- 
tion may be construed to permit a different loca- 
tion of the eyellipse, since it provides that the 95 
percent eye range contour must be geometrically 
positioned "around" the longitudinal centerline of 
the driver's seat. Therefore, the definition is 
being amended to clarify the location of the 
eyellipse by requiring its geometric center to be 
positioned on the longitudinal centerline of the 
driver's designated seating position. 

Several petitions for reconsideration of the 
amendment have raised the possibility that the 
definition of plan view reference line may im- 
pose an unintended hardship on manufacturers of 
smaller cars. The effect of the definition is to 
relocate the eyellipse slightly outboard of the 
location prescribed in the standard prior to the 
amendment. This change may make it imprac- 
ticable for manufacturers of smaller cars to com- 



ply with the wiped-area requirements of the 
standard. Therefore, the definition is being 
further amended to permit optional positioning of 
the eyellipse on the plan view reference line in 
the manner prescribed in the standard prior to 
the previous amendment. 

Neither of these revisions appreciably alters 
the amount of the windshield surface which wip- 
ing systems must wipe under the standard. Hence 
the amendments will have no adverse effect on 
motor vehicle safety. 

Paragraph S4.1.1.3 of the amendment provides, 
in part, that the lowest frequency or speed of 
windshield wiping systems must be at least 20 
cycles per minute regardless of engine speed and 
engine load. The Administrator has received 
petitions asking that a frequency or speed lower 
than 20 cycles per minute be allowed. The peti- 
tioners state that such a lower frequency or speed 
will be useful under conditions of very light 
precipitation or wheel spray, and that retention 
of the 20-cycle-per-minut« minimum will preclude 
the use of so-called "intermittent" windshield 
wiping systems. The Administrator has con- 
cluded that the standard should be amended to 
allow manufacturers to i»e systems which can 
operate at a frequency or speed of less than 20 
cycles per minute so long as the driver of the 
vehicle has available a system capable of op- 
erating at at least two other frequencies or speeds, 
differing by at least 15 cycles per minute, the 
lower of which is at least 20 cycles per minute. 
The net effect of this change is to allow as 
many different frequencies or speeds as the manu- 
facturer desires as long as at least two of these 
speeds or frequencies meet the specified require- 
ments. 



PART 671; S 104— PRE 6 



l**cHv*t January 1, 1969 

Since these amendments provide clarification, (Sees. 103, 119, National Traffic and Motor 

relieve a hardship and impose no additional Vehicle Safety Act of 1966 (15 U.S.C. 1392, 

burden on any person, notice and public proce- 1470) ; delegation of authority of April 24, 1968 

dure thereon are unnecessary. (33 F.R. 6538)). 

In consideration of the foregoing, § 371.21 of ^^^^ -^ Washington, D.C., on July 31, 1968. 

Part 371, Federal Motor Vehicle Safety Stand- s » > j ^ 

ards. Motor Vehicle Safety Standard No. 104 (32 n • 

F.R. 2410), as amended (33 F.R. 6466), is Lowell K. Bndwell, 

amended, effective July 31, 1968. . . . F«ie™l Highway Administrator. 

It is found, for good cause shown, that an effec- 
tive date sooner than 180 days after the issuance 33 F.R. 11117 
of these amendments is in the public interest. August 6, 1968 



PART 571 ; S 104^PRE 6 " 



MOTOR VEHICLE SAFETY STANDARD NO. 104 
Windshield Wiping and Washing Systems— Passenger Cars, Multipurpose Passenger 

Vehicles, Trucks, and Buses 



51. Scope. This standard specifies 
requirements for windshield wiping and washing 
systems. 

52. Application. This standard applies to 
passenger cars, multipurpose passenger vehicles, 
trucks, and buses. 

53. Definitions. The term "seating reference 
point" is substituted for the terms "manikin H 
point" and "H point" wherever either of those 
terms appears in any SAE Standard or SAE 
Recommended Practice referred to in this 
standard. 

"Daylight opening" means the maximum un- 
obstructed opening through the glazing surface, 
as defined in paragraph 2.3.12 of section E, 
Ground Vehicle Practice, SAE Aerospace-Auto- 
motive Drawing Standards, September 1963. 

"Glazing surface reference line" means the line 
resulting from the intersection of the glazing sur- 
face and a horizontal plane 25 inches above the 
seating reference point, as shown in Figure 1 of 
SAE Recommended Practice J903a, "Passenger 
Car Windshield Wiper Systems," May 1966. 

"Overall width" means the maximum overall 
body width dimension "W116," as defined in 
section E, Ground Vehicle Practice, SAE 
Aerospace-Automotive Drawing Standards, 
September 1963. 

"Plan view reference line" means— 

(a) For vehicles with bench-type seats, a line 
parallel to the vehicle longitudinal centerline out- 
board of the steering wheel centerline 0.15 times 
the difference between one-half of the shoulder 
room dimension and the steering wheel center- 
line-to-car-centerline dimension as shown in 
Figure 2 of SAE Recommended Practice J903a, 
May 1966; or 



(b) For vehicles with individual-type seats, 
either— 

(i) A line parallel to the vehicle longitudinal 
centerline which passes through the center of 
the driver's designated seating position; or 

(ii) A line parallel to the vehicle longitu- 
dinal centerline located so that the geometric 
center of the 95 percent eye range contour is 
positioned on the longitudinal centerline of the 
driver's designated seating position. 
"Shoulder room dimension" means the front 
shoulder room dimension "W3" as defined in 
section E, Ground Vehicle Practice, SAE 
Aerospace-Automotive Drawing Standards, 
September 1963. 

"95% eye range contour" means th 95th percen- 
tile tangential cutoff specified in SAE Recom- 
mended Practice J941, "Passenger Car Driver's 
Eye Range," November 1965. 

S4. Requirements. 

S.41 Windshield wiping system. Each vehicle 
shall have a power-driven windshield wiping 
system that meets the requirements of S4.1.1. 

S4.1 .1 Frequency. 

54.1.1.1 Each windshield wiping system shall 
have at least two frequencies or speeds. 

54.1.1.2 One frequency or speed shall be at 
least 45 cycles per minute regardless of engine 



load and engine speed. 



S4.1 .1 .3 Regardless of engine speed and engine 
load, the highest and one lower frequency or speed 
shall differ by at least 15 cycles per minute. Such 
lower frequency or speed shall be at least 20 cycles 
per minute regardless of engine speed and engine 
load. 



PART 571; S 104-1 



Table I. Passenger cars of less than 60 inches in overall 
width. 



Column 1 


Column 2 


Column 3 


Column 4 


Column 5 


Column 6 




Minimum 




Angles in 


Degrees 






Percent 

TO BE 










Area 












Wiped 


Left 


Right 


Up 


Down 


A 


80 


16 


49 


7 


5 


B 


94 


13 


46 


4 


3 


C 


99 


7 


15 


3 


1 



Table II. Passenger cars of 60 or more but less than 
64 inches in overall width. 



Column 1 


Column 2 


Column 3 


Column 4 


Column 5 


Column 6 




Minimum 




Angles in 


Degrees 






Percent 

TO BE 










Area 












Wiped 


Left 


Right 


Up 


Down 


A 


80 


17 


51 


8 


5 


B 


94 


13 


49 


4 


3 


C 


99 


7 


15 


3 


1 



Table III. Passenger cars of 64 or more but less than 
68 inches in overall width. 



Column 1 


Column 2 


Column 3 


Column 4 


Column 5 


Column 6 




Minimum 




Angles in 


Degrees 






Percent 
to be 










Area 












Wiped 


Left 


Right 


Up 


Down 


A 


80 


17 


53 


9 


5 


B 


94 


14 


51 


5 


3 


C 


99 


8 


15 


4 


1 



Table IV. Passenger cars of 68 or more inches in 
overall width. 

Column 1 Column 2 Column 3 Column 4 Column 5 Column 6 



Minimum 
Perce.nt 
Area to be 



Angles in Degrees 





Wiped 


Left 


Right 


Up 


IDOWN 


A 


80 


18 


56 


10 


5 


B 


94 


14 


53 


5 


3 


C 


99 


10 


15 


5 


1 



S4.1.1.4 Compliance with subparagraphs 
S4.1.1.2 and S4.1.1.3 may be demonstrated by 
testing under the conditions specified in sections 
4.1.1 and 4.1.2 of SAE Recommended Practice 
J903a, May 1966. 

S4.1.2 Wiped area. When tested wet in ac- 
cordance with SAE Recommended Practice 
J903a, May 1966, each passenger car windshield 
wiping system shall wipe the percentage of 
Areas A, B, and C of the windshield (established 
in accordance with S4. 1.2.1) that (1) is specified 
in column 2 of the applicable table following 
subparagraph S4. 1.2.1; and (2) is within the 
area bounded by a perimeter line on the glazing 
surface one inch from the edge of the daylight 
opening. 

S4.1.2.1 Areas A, B, and C shall be estab- 
lished as shown in Figures 1 and 2 of SAE 
Recommended Practice J903a, May 1966, using 
the angles specified in Columns 3 through 6 of 
Table I, II, III or IV, as applicable. 

S4.2 Windshield washing system. 

54.2.1 Each passenger car shall have a wind- 
shield washing system that meets the require- 
ments of SAE Recommended Practice J942, 
"Passenger Car Windshield Washer Systems" 
November 1965, except that the reference to "the 
effective wipe pattern defined in SAE J903, para- 
graph 3.1.2" in paragraph 3.1 of SAE Recom- 
mended Practice J942 shall be deleted and "the 
areas established in accordance with subpara- 
graph S4. 1.2.1 of Motor Vehicle Safety Standard 
No. 104" shall be inserted in lieu thereof. 

54.2.2 Each multipurpose passenger vehicle, 
truck and bus shall have a windshield washing 
system that meets the requirements of SAE 
Recommended Practice J942, November 1965, 
except that the reference to "the effective wipe 
pattern defined in SAE J903, paragraph 3.1.2" in 
paragraph 3.1 of SAE Recommended Practice 
J942 shall be deleted and "the pattern design by 
the manufacturer for the windshield wiping sys- 
tem on the exterior surface of the windshield 
glazing" shall be inserted in lieu thereof. 

33 F.R. 6467 
April 27, 1968 



PART 571; S 104-2 



MOTOR VEHICLE SAFETY STANDARD NO. 104 
Windshield Wiping and Washing Systems— Passenger Cars, Multipurpose Passenger 

Vehicles, Trucks, and Buses 



51. Scope. This standard specifies 
requirements for windshield wiping and washing 
systems. 

52. Application. This standard applies to 
passenger cars, multipurpose passenger vehicles, 
trucks, and buses. 

53. Definitions. The term "seating reference 
point" is substituted for the terms "manikin H 
point" and "H point" wherever either of those 
terms appears in any SAE Standard or SAE 
Recommended Practice referred to in this 
standard. 

"Daylight opening" means the maximum un- 
obstructed opening through the glazing surface, 
as defined in paragraph 2.3.12 of section E, 
Ground Vehicle Practice, SAE Aerospace-Auto- 
motive Drawing Standards, September 1963. 

"Glazing surface reference line" means the line 
resulting from the intersection of the glazing sur- 
face and a horizontal plane 25 inches above the 
seating reference point, as shown in Figure 1 of 
SAE Recommended Practice J903a, "Passenger 
Car Windshield Wiper Systems," May 1966. 

"Overall width" means the maximum overall 
body width dimension "W116," as defined in 
section E, Ground Vehicle Practice, SAE 
Aerospace-Automotive Drawing Standards, 
September 1963. 

"Plan view reference line" means— 

(a) For vehicles with bench-type seats, a line 
parallel to the vehicle longitudinal centerline out- 
board of the steering wheel centerline 0.15 times 
the difference between one-half of the shoulder 
room dimension and the steering wheel center- 
line-to-car-centerline dimension as shown in 
Figure 2 of SAE Recommended Practice J903a, 
May 1966; or 



(b) For vehicles with individual-type seats, 
either— 

(i) A line parallel to the vehicle longitudinal 
centerline which passes through the center of 
the driver's designated seating position; or 

(ii) A line parallel to the vehicle longitu- 
dinal centerline located so that the geometric 
center of the 95 percent eye range contour is 
positioned on the longitudinal centerline of the 
driver's designated seating position. 
"Shoulder room dimension" means the front 
shoulder room dimension "W3" as defined in 
section E, Ground Vehicle Practice, SAE 
Aerospace-Automotive Drawing Standards, 
September 1963. 

"95% eye range contour" means th 95th percen- 
tile tangential cutoff specified in SAE Recom- 
mended Practice J941, "Passenger Car Driver's 
Eye Range," November 1965. 

S4. Requirements. 

S.41 Windshieid wiping system. Each vehicle 
shall have a power-driven windshield wiping 
system that meets the requirements of S4.1.1. 

S4.1.1 Frequency. 

54.1.1.1 Each windshield wiping system shall 
have at least two frequencies or speeds. 

54.1.1.2 One frequency or speed shall be at 
least 45 cycles per minute regardless of engine 
load and engine speed. 

54.1 .1 .3 Regardless of engine speed and engine 
load, the highest and one lower frequency or speed 
shall differ by at least 15 cycles per minute. Such 
lower frequency or speed shall be at least 20 cycles 
per minute regardless of engine speed and engine 
load. 



PART 571; S 104-1 



Table I. Passenger cars of less than 60 inches in overall 
width. 



Column l 


Column 2 


Column 3 


Column 4 


Column 5 


Column 6 




Minimum 




Angles in 


Degrees 






Percent 

TO BE 










Area 












Wiped 


Left 


Right 


Up 


Down 


A 


80 


16 


49 


7 


5 


B 


94 


13 


46 


4 


3 


C 


99 


7 


15 


3 


1 



Table II. Passenger cars of 60 or more but less than 
64 inches in overall width. 



Column 1 


Column 2 


Column 3 


Column 4 


Column 5 


Column 6 




Minimum 




Angles in 


Degrees 






Percent 

TO BE 










Area 












Wiped 


Left 


Right 


Up 


Down 


A 


80 


17 


51 


8 


5 


B 


94 


13 


49 


4 


3 


C 


99 


7 


15 


3 


1 



Table III. Passenger cars of 64 or more but less than 
68 inches in overall width. 



Column i 


Column 2 


Column 3 


Column 4 


Column 5 


Column 6 




Minimum 




Ancles in 


Degrees 






Percent 
to be 










Area 












Wiped 


Left 


Right 


Up 


Down 


A 


80 


17 


53 


9 


5 


B 


94 


14 


51 


5 


3 


C 


99 


8 


15 


4 


1 



Table IV. Passenger cars of 68 or more inches in 
overall width. 



Column 1 


Column 2 


Column 3 


Column 4 


Column 5 


Column 6 




Minimum 




Angles in 


Degrees 






Percent 
to be 










Area 












Wiped 


Left 


Right 


Up 


Down 


A 


80 


18 


56 


10 


5 


B 


94 


14 


53 


5 


3 


C 


99 


10 


15 


5 


1 



S4. 1.1.4 Compliance with subparagraphs 
S4.1.1.2 and S4.1.1.3 may be demonstrated by 
testing under the conditions specified in sections 
4.1.1 and 4.1.2 of SAE Recommended Practice 
J903a, May 1966. 

S4.1.2 Wiped area. When tested wet in ac- 
cordance with SAE Recommended Practice 
J903a, May 1966, each passenger car windshield 
wiping system shall wipe the percentage of 
Areas A, B, and C of the windshield (established 
in accordance with S4. 1.2.1) that (1) is specified 
in column 2 of the applicable table following 
subparagraph S4. 1.2.1; and (2) is within the 
area bounded by a perimeter line on the glazing 
surface one inch from the edge of the daylight 
opening. 

S4.1.2.1 Areas A, B, and C shall be estab- 
lished as shown in Figures 1 and 2 of SAE 
Recommended Practice J903a, May 1966, using 
the angles specified in Columns 3 through 6 of 
Table I, II, III or IV, as applicable. 

S4.2 Windshield washing system. 

54.2.1 Each passenger car shall have a wind- 
shield washing system that meets the require- 
ments of SAE Recommended Practice J942, 
"Passenger Car Windshield Washer Systems" 
November 1965, except that the reference to "the 
effective wipe pattern defined in SAE J903, para- 
graph 3.1.2" in paragraph 3.1 of SAE Recom- 
mended Practice J942 shall be deleted and "the 
areas established in accordance with subpara- 
graph S4. 1.2.1 of Motor Vehicle Safety Standard 
No. 104" shall be inserted in lieu thereof. 

54.2.2 Each multipurpose passenger vehicle, 
truck and bus shall have a windshield washing 
system that meets the requirements of SAE 
Recommended Practice J942, November 1965, 
except that the reference to "the effective wipe 
pattern defined in SAE J903, paragraph 3.1.2" in 
paragraph 3.1 of SAE Recommended Practice 
J942 shall be deleted and "the pattern design by 
the manufacturer for the windshield wiping sys- 
tem on the exterior surface of the windshield 
glazing" shall be inserted in lieu thereof. 

33 F.R. 6467 
April 27, 1968 



PART 571; S 104-2 



Effective: September 1. 1974 



PREAMBLE TO MOTOR VEHICLE SAFETY STANDARD NO. 105a 

Hydraulic Brake Systems 
(Docket No. 70-27; Notice 5) 



This notice amends Part 571 of Title 49, Code 
of Federal Regulations, to add a new Motor 
Vehicle Safety Standard No. 105a (49 CFR 
§ 571. 105a) that establishes requirements for 
motor vehicle hydraulic brake systems and park- 
ing brake systems. A notice of proposed rule- 
making on this subject was published on Novem- 
ber 11, 1970 (35 F.R. 17345). 

Federal Standard No. 105, in effect since Jan- 
uary 1, 1968, represents the initial Federal effort 
to specify braking requirements for motor ve- 
hicles. The standard requires that passenger 
cars be equipped with a split service brake sys- 
tem, and have stopping ability based upon de- 
celeration rates specified in an SAE Recom- 
mended Practice. Requirements for fade and 
recovery, water recovery, and stability while 
braking are also included in the standard. These 
requirements do not, however, represent the full 
capabilities of modern braking technology. 
Braking continues to be the most important 
single element of accident avoidance from the 
standpoint of vehicle performance. The full 
utilization of the industry's technological capa- 
bility in this area, within the limits of reasonable 
cost, is therefore of highest importance to the 
safety effort. 

The requirements of this standard are specified 
in terms of performance on a surface of rela- 
tively high skid number. The NHTSA recog- 
nizes the importance to safety of good braking 
performance on surfaces such as wet or icy roads. 
It is monitoring closely the development work 
in progress en methods, such as antilock systems, 
designed to enhance vehicle performance over a 
wide variety of surfaces, in preparation for fu- 
ture rulemaking action adding performance re- 
quirements in this area. Until such requirements 
are made effective, this agency assumes that 



manufacturers will design their vehicles for safe 
braking performance on all types of road sur- 
faces, while continuing to work on, and make 
provision for, more advanced braking systems. 

The notice issued in November 1970 proposed 
extension of applicability of Standard No. 105 
to other vehicle types and covered the same fac- 
tors deemed important in the earlier standard. 
These include stopping distance, Imear stability 
while stopping, fade resistance, and fade recov- 
ery. The notice also proposed features in hy- 
draulic braking systems that could warn against 
malfunction, and stop the vehicle should a mal- 
function appear in the normal service system. 
The amended standard covers each of these as- 
pects as discussed below. 

1. Applicability. Standard No. 105 applies to 
passenger cars, and has been extended to specify 
requirements for the first time for multipurpose 
passenger vehicles, trucks, and buses equipped 
with hydraulic brake systems. A definition of 
brake power unit has been adopted and appro- 
priate modifications made in the text to clarify 
that vehicles with central hydraulic power sys- 
tems were included in the Notice. Standard No. 
105a does not apply to vehicles equipped with 
"air over hydraulic" systems, which remain 
within the purview of Standard No. 121, Air 
Brake Systems. 

2. Effective date: to meet the proposed effec- 
tive date of October 1, 1972, equipment and 
performance requirements would have been sub- 
stantially weaker than those that have been 
adopted and the NHTSA has determined that a 
later effective date is, overall, in the public in- 
terest. It is therefore set at September 1, 1974. 

3. Service brake system. All vehicles with hy- 
draulic brake systems are reouired to have a 



PART 671; S 105 —PRE 1 



EihcHv*: S*pl*mb«r 1, 1974 



split service brake system, with partial failure 
or "emergency" braking features. Effectiveness 
of the system is demonstrated by a series of road 
tests covering stopping distance, stability, and 
fade and recovery, water recovery, and spike 
stops. 

A. Stopping distance. As the proposal noted, 
"perhaps the most important indication of brake 
performance is the distance in which a brake 
system can stop a vehicle from a given speed." 
Stopping distances were proposed from 30 mph, 
60 mph, and 80 mph and maximum attainable 
vehicle speed, under various load and system 
conditions, based upon vehicle category or weight. 
These tests included stops with the vehicle at a 
lightly loaded weight, and stops under partial 
failure conditions. The following illustrate ex- 
amples of the proposal and amendment. In ad- 
dition to the stopping distances discussed below, 
stopping distances from 30 mph, 80 mph, and 
maximum attainable vehicle speed are also speci- 
fied. 

Passenger cars. It was proposed that passen- 
ger cars demonstrate the ability to stop in 185 
feet from 60 mph under adverse loading condi- 
tions. The stopping distance adopted, 194 feet, 
is only slightly longer. According to Consumer 
Information data submitted by manufacturers of 
1972 passenger cars, contemporary vehicles 
ranked 26th to 61st would be unable to meet this 
stopping distance requirement. This new re- 
quirement will result in a substantial upgrading 
of passenger car stopping ability. Currently 
under Standard No. 105, passenger cars must 
demonstrate the ability to stop in 646 feet from 
60 mph under partial failure conditions. The 
new standard lowers this distance to 431 feet, 
an increase from the proposed 388 feet. The 
same stopping distance requirement must be met 
with an inoperative brake power assist or brake 
power unit. 

Vehicles with GVWR of 10,000 pounds or less. 
Vehicles other than passenger cars with a gross 
vehicle weight rating of 10,000 ix>unds or less, 
must demonstrate the ability to stop from 60 
mph in 216 feet under adverse loading condi- 
tions, and in 484 feet under partial failure 
conditions. 

Vehicles with GVWE greater than 10,000 
pounds. • Vehicles in this category must demon- 



strate an ability to stop from 60 mph in 245 feet 
under adverse loading conditions, and in 553 feet 
under partial failure conditions. 

B. Stability of vehicle while stopping. As 
proposed, a vehicle will be required to stop 
(other than in spike stops) without any part of 
it leaving a 12- foot- wide lane. Wheel lockup is 
permitted at a speed below 10 mph and lockup 
of only one wheel not controlled by an antilock 
system is permissible at speeds in excess of 
10 mph. 

C. Fade and recovery. Brake fade character- 
istics are critical from the standpoint of retaining 
adequate stopping power despite the high tem- 
peratures created by prolonged or severe use. A 
vehicle will demonstrate fade and recovery capa- 
bility in two tests, by making a number of fade 
stops from 60 mph if it is a vehicle with a GVWR 
of 10,000 pounds or less, or fade snubs from 40 
mph to 20 mph, if it is a heavier vehicle. The 
latter represents a modification of the proposed 
snub speed range of 50 mph to 15 mph. The 
proposed maximum speed fade recovery test has 
not been adopted; the effectiveness test at maxi- 
mum attainable vehicle speed should indicate 
whether a brake system will experience problems 
with fade. 

D. Water recovery. Service brake systems must 
also demonstrate an acceptable recovery after 
exposure to water. The method of imjnersion 
has been modified on the basis of comments that 
the method proposed would necessitate use of a 
trough 880 feet long. Instead, the amendment 
specifies that the vehicle shall be driven for not 
less than 2 minutes at a speed of 5 mph, in any 
combination of forward and reverse directions, 
through a trough having a water depth of 6 
inches. This change should clarify the test re- 
quirement as well as simplifying enforcement 
procedures. 

E. Spike stops. The spike stop proposal has 
been adopted, with a revision to allow 6 check 
stops (instead of one), at least one of which 
meets the requirements of the specified distance 
and pedal force. This allowance recognizes 
variability of test drivers and vehicles. 

4. Parking brake system. The parking brake 
system proposal has also been adopted. When 
the parking brakes are applied, with a force not 
exceeding 90 pounds for a hand-operated system 



PART 571; S 105 —PRE 2 



Effactiv*: S*ptemb*r 1, 1974 



PREAMBLE TO MOTOR VEHICLE SAFETY STANDARD NO. 105a 

Hydraulic Brake Systems 
(Docket No. 70-27; Notice 5) 



This notice amends Part 571 of Title 49, Code 
of Federal Regulations, to add a new Motor 
Vehicle Safety Standard No. 105a (49 CFR 
§ 571.105a) that establishes requirements for 
motor vehicle hydraulic brake systems and park- 
ing brake systems. A notice of proposed rule- 
making on this subject was published on Novem- 
ber 11, 1970 (35 F.R. 17345). 

Federal Standard No. 105, in effect since Jan- 
uary 1, 1968, represents the initial Federal effort 
to specify braking requirements for motor ve- 
hicles. The standard requires that passenger 
cars be equipped with a split service brake sys- 
tem, and have stopping ability based upon de- 
celeration rates specified in an SAE Recom- 
mended Practice. Requirements for fade and 
recovery, water recovery, and stability while 
braking are also included in the standard. These 
requirements do not, however, represent the full 
capabilities of modern braking technology. 
Braking continues to be the most important 
single element of accident avoidance from the 
standpoint of vehicle performance. The full 
utilization of the industry's technological capa- 
bility in this area, within the limits of reasonable 
cost, is therefore of highest importance to the 
safety effort. 

The requirements of this standard are specified 
in terms of performance on a surface of rela- 
tively high skid number. The NHTSA recog- 
nizes the importance to safety of good braking 
performance on surfaces such as wet or icy roads. 
It is monitoring closely the development work 
in progress en methods, such as antilock systems, 
designed to enhance vehicle performance over a 
wide variety of surfaces, in preparation for fu- 
ture rulemaking action adding performance re- 
quirements in this area. Until such requirements 
are made effective, this agency assumes that 



manufacturers will design their vehicles for safe 
braking performance on all types of road sur- 
faces, while continuing to work on, and make 
provision for, more advanced braking systems. 

The notice issued in November 1970 proposed 
extension of applicability of Standard No. 105 
to other vehicle types and covered the same fac- 
tors deemed important in the earlier standard. 
These include stopping distance, hnear stability 
while stopping, fade resistance, and fade recov- 
ery. The notice also proposed features in hy- 
draulic braking systems that could warn against 
malfunction, and stop the vehicle should a mal- 
function appear in the normal service system. 
The amended standard" covers each of these as- 
pects as discussed below. 

1. Applicability. Standard No. 105 applies to 
passenger cars, and has been extended to specify 
requirements for the first time for multipurpose 
passenger vehicles, trucks, and buses equipped 
with hydraulic brake systems. A definition of 
brake power unit has been adopted and appro- 
priate modifications made in the text to clarify 
that vehicles with central hydraulic power sys- 
tems were included in the Notice. Standard No. 
105a does not apply to vehicles equipped with 
"air over hydraulic" systems, which remain 
within the purview of Standard No. 121, Air 
Brake Systems. 

2. Effective date: to meet the proposed effec- 
tive date of October 1, 1972, equipment and 
performance requirements would have been sub- 
stantially weaker than those that have been 
adopted and the NHTSA has determined that a 
later effective date is, overall, in the public in- 
terest. It is therefore set at September 1, 1974. 

3. Service brake system. All vehicles with hy- 
draulic brake systems are reauired to have a 



PART 571; S 105 —PRE 1 



EffacHva: Saptombar I, 1974 



split service brake system, with partial failure 
or "emergency" braking features. Effectiveness 
of the system is demonstrated by a series of road 
tests covering stopping distance, stability, and 
fade and recovery, water recovery, and spike 
stops. 

A. Stopping distance. As the proposal noted, 
"perhaps the most important indication of brake 
performance is the distance in which a brake 
system can stop a vehicle from a given speed." 
Stopping distances were proposed from 30 mph, 
60 mph, and 80 mph and maximum attainable 
vehicle speed, under various load and system 
conditions, based upon vehicle category or weight. 
These tests included stops with the vehicle at a 
lightly loaded weight, and stops under partial 
failure conditions. The following illustrate ex- 
amples of the proposal and amendment. In ad- 
dition to the stopping distances discussed below, 
stopping distances from 30 mph, 80 mph, and 
maximum attainable vehicle speed are also speci- 
fied. 

Passenger cars. It was proposed that passen- 
ger cars demonstrate the ability to stop in 185 
feet from 60 mph under adverse loading condi- 
tions. The stopping distance adopted, 194 feet, 
is only slightly longer. According to Consumer 
Information data submitted by manufacturers of 
1972 passenger cars, contemporary vehicles 
ranked 26th to 61st would be unable to meet this 
stopping distance requirement. This new re- 
quirement will result in a substantial upgrading 
of passenger car stopping ability. Currently 
imder Standard No. 105, passenger cars must 
demonstrate the ability to stop in 646 feet from 
60 mph under partial failure conditions. The 
new standard lowers this distance to 431 feet, 
an increase from the proposed 388 feet. The 
same stopping distance requirement must be met 
with an inoperative brake power assist or brake 
power unit. 

Vehicles with GVWR of 10,000 pounds or less. 
Vehicles other than passenger cars with a gross 
vehicle weight rating of 10,000 {wunds or less, 
must demonstrate the ability to stop from 60 
mph in 216 feet under adverse loading condi- 
tions, and in 484 feet under partial failure 
conditions. 

Vehicles with GVWR greater than 10,000 
pounds. • Vehicles in this category must demon- 



strate an ability to stop from 60 mph in 245 feet 
under adverse loading conditions, and in 553 feet 
under partial failure conditions. 

B. Stability of vehicle while stopping. As 
proposed, a vehicle will be required to stop 
(other than in spike stops) without any part of 
it leaving a 12-foot-wide lane. Wheel lockup is 
permitted at a speed below 10 mph and lockup 
of only one wheel not controlled by an antilock 
system is permissible at speeds in excess of 
10 mph. 

C. Fade and recovery. Brake fade character- 
istics are critical from the standpoint of retaining 
adequate stopping power despite the high tem- 
peratures created by prolonged or severe use. A 
vehicle will demonstrate fade and recovery capa- 
bility in two tests, by making a number of fade 
stops from 60 mph if it is a vehicle with a GVWR 
of 10,000 pounds or less, or fade snubs from 40 
mph to 20 mph, if it is a heavier vehicle. The 
latter represents a modification of the proposed 
snub speed range of 50 mph to 15 mph. The 
proposed maximum speed fade recovery test has 
not been adopted; the effectiveness test at maxi- 
mum attainable vehicle speed should indicate 
whether a brake system will experience problems 
with fade. 

D. Water recovery. Service brake systems must 
also demonstrate an acceptable recovery after 
exposure to water. The method of immersion 
has been modified on the basis of comments that 
the method proposed would necessitate use of a 
trough 880 feet long. Instead, the amendment 
specifies that the vehicle shall be driven for not 
less than 2 minutes at a speed of 5 mph, in any 
combination of forward and reverse directions, 
through a trough having a water depth of 6 
inches. This change should clarify the test re- 
quirement as well as simplifying enforcement 
procedures. 

E. Spike stops. The spike stop proposal has 
been adopted, with a revision to allow 6 check 
stops (instead of one), at least one of which 
meets the requirements of the specified distance 
and pedal force. This allowance recognizes 
variability of test drivers and vehicles. 

4. Parkhig brake system. The parking brake 
system proposal has also been adopted. AVhen 
the parking brakes are applied, with a force not 
exceeding 90 pounds for a hand-operated system 



PART 571; S 105 —PRE 2 



ill««Nv«i S«pMmb«r 1, 1974 



or 125 pounds for a foot-operated system, the 
parking brake system shall be capable of holding 
the vehicle stationary for 5 minutes on a 30 per- 
cent grade (20 per cent for vehicles of more 
than 10,000 pounds GVWR) in both forward 
and reverse directions. Optional requirements 
have been adopted for vehicles with a GVWR 
of 10,000 pounds or less, equipped with a trans- 
mission utilizing a parking pawl or detent mech- 
anism within the transmission assembly. "Vehicles 
so equipped may demonstrate compliance by 
(1) parking with both the parking brake and 
pawl engaged on a 30 per cent grade, (2) park- 
ing on a 20 per cent grade with only the parking 
brake engaged, and (3) being impacted front 
and rear, on a level surface, by a 4,000 pound 
moving barrier without disengagement or frac- 
ture of the pawl or detent mechanism. 

5. Reservoirs. The master cylinder reservoir 
proposal has been adopted with modifications 
that allow balance ports and compartmentalized 
reservoirs in a single integrated master cylinder 
body and reservoir assembly, and that reduce 
fluid reservoir capacity requirements from 150 
per cent to 100 per cent. The proposed cover, 
seal, and retention devices have not been adopted 
since pressure differential warning and low fluid 
level warning should provide a sufficient safety 
factor. The proposal was intended also to cover 
reservoir requirements in systems not using 
master cylinders and the revised wording of the 
section clarifies this point. 

6. Brake system indicator lamp. The proposal 
would have required separate lamps to indicate 
when the parking brake is applied, and when a 
failure has occurred in the service brake system. 
Standard No. 105a requires only one lamp to 
serve these functions, to be labeled "Brake". 
Either the wording or the lens may be the color 
red. The lamp must light in the event of pres- 
sure failure in any part of the service brake 
system, other than a structural failure of a hous- 
ing that is common to two or more subsystems, 
before or upon application of 50 pounds of pedal 
force upon a manually-operated service brake, 
or 25 pounds upon a service brake with a brake 
power assist unit, or when the supply pressure 
in a brake power unit drops to not less than one- 
half of the normal system pressure. The lamp 
must also light, without the application of pedal 



force, when the level of brake fluid in the master 
cylinder reservoir drops to less than the recom- 
mended safe level specified by the manufacturer, 
or to not less than one-fourth the fluid reservoir 
capacity in any reservoir compartment, which- 
ever is greater. This does not preclude the use 
of translucent covers or sight gauges in addition 
to the required lamp. Additionally, the lamp 
must illuminate when there is a total electrical 
failure in an antilock or brake proportioning 
system. All indicator lamps shall be activated 
when the ignition switch is turned from the "on" 
to the "start" position, which includes the air 
start condition on diesel-engine vehicles. The 
lamps will be deactivated upon return of the 
switch to the "on" position. No time interval is 
specified for deactivation, as the NHTSA recog- 
nizes that instant deactivation is impracticable 
for continuous sensing units. 

7. Miscellaneous. The NHTSA proposed that 
service brakes be installed so that the lining 
thickness of drum brake shoes and disc brake 
pads might be visually inspected without remov- 
ing the drums or pads. The possibility that 
contaminants may enter the system if plugs are 
removed, the differences between riveted and 
bonded lining thickness, and the location of in- 
spection ports, were some of the technical and 
safety factors weighing in the conclusion to 
abandon this proposal. 

The agency decided against the proposal that 
would have established suspension system dur- 
ability requirements to be met following comple- 
tion of tests. Since the vehicle must remain 
within a 12-foot-wide lane as a condition of the 
stopping distance tests, this will be a satisfactory 
demonstration of suspension system integrity. 

Effective date: September 1, 1974. Because 
of the necessity to allow manufacturers sufficient 
production leadtime, it is found for good cause 
shown that an effective date later than one year 
after issuance of this rule is in the public interest. 

In consideration of the foregoing, Title 49, 
Code of Federal Regulations, is amended by 
adding § 571.105a, Motor Vehicle Safety Stand- 
ard No. 105a, Hydraulic Brake Systems, as set 
forth below. 

This notice is issued under the authority of 
sections 103 and 119 of the National Traffic and 



PART 671; S 105 —PRE 8 



I, I9M 

Motor Vehicle Safety Act of 1966 (15 U.S.C. Issued on : August 23, 1972. 

1392, 1407) and the delegation of authority tnm Douglas W. Toms 

the Secretary of Transportation to the National Administrator 

Highway Traffic Safety Administrator, 49 CFR 37 f.R. 17970 

1-51. Soptambtr 2, 1972 



PART 571; S 105 —PRE 4 



i4f«cHv«i S«ptamb*r I, 1974 



or 125 pounds for a foot-operated system, the 
parking brake system shall be capable of holding 
the vehicle stationary for 5 minutes on a 30 per- 
cent grade (20 per cent for vehicles of more 
than 10,000 pounds GVWR) in both forward 
and reverse directions. Optional requirements 
have been adopted for vehicles with a GVWR 
of 10,000 pounds or less, equipped with a trans- 
mission utilizing a parking pawl or detent mech- 
anism within the transmission assembly. Vehicles 
so equipped may demonstrate compliance by 
(1) parking with both the parking brake and 
pawl engaged on a 30 per cent grade, (2) park- 
ing on a 20 per cent grade with only the parking 
brake engaged, and (3) being impacted front 
and rear, on a level surface, by a 4,000 pound 
moving barrier without disengagement or frac- 
ture of the pawl or detent mechanism. 

5. Reservoirs. The master cylinder reservoir 
proposal has been adopted with modifications 
that allow balance ports and compartmentalized 
reservoirs in a single integrated master cylinder 
body and reservoir assembly, and that reduce 
fluid reservoir capacity requirements from 150 
per cent to 100 per cent. The proposed cover, 
seal, and retention devices have not been adopted 
since pressure differential warning and low fluid 
level warning should provide a sufficient safety 
factor. The proposal was intended also to cover 
reservoir requirements in systems not using 
master cylinders and the revised wording of the 
section clarifies this point. 

6. Brake system indicator lamp. The proposal 
would have required separate lamps to indicate 
when the parking brake is applied, and when a 
failure has occurred in the service brake system. 
Standard No. 105a requires only one lamp to 
serve these fimctions, to be labeled "Brake". 
Either the wording or the lens may be the color 
red. The lamp must light in the event of pres- 
sure failure in any part of the service brake 
system, other than a structural failure of a hous- 
ing that is common to two or more subsystems, 
before or upon application of 50 pounds of pedal 
force upon a manually-operated service brake, 
or 25 pounds upon a service brake with a brake 
power assist unit, or when the supply pressure 
in a brake power unit drops to not less than one- 
half of the normal system pressure. The lamp 
must also light, without the application of pedal 



force, when the level of brake fluid in the master 
cylinder reservoir drops to less than the recom- 
mended safe level specified by the manufacturer, 
or to not less than one-fourth the fluid reservoir 
capacity in any reservoir compartment, which- 
ever is greater. This does not preclude the use 
of translucent covers or sight gauges in addition 
to the required lamp. Additionally, the lamp 
must illuminate when there is a total electrical 
failure in an antilock or brake proportioning 
system. All indicator lamps shall be activated 
when the ignition switch is turned from the "on" 
to the "start" position, which includes the air 
start condition on diesel-engine vehicles. The 
lamps will be deactivated upon return of the 
switch to the "on" position. No time interval is 
specified for deactivation, as the NHTSA recog- 
nizes that instant deactivation is impracticable 
for continuous sensing units. 

7. Miscellaneous. The NHTSA proposed that 
service brakes be installed so that the lining 
thickness of drum brake shoes and disc brake 
pads might be visually inspected without remov- 
ing the drums or pads. The possibility that 
contaminants may enter the system if plugs are 
removed, the differences between riveted and 
bonded lining thickness, and the location of in- 
spection ports, were some of the technical and 
safety factors weighing in the conclusion to 
abandon this proposal. 

The agency decided against the proposal that 
would have established suspension system dur- 
ability requirements to be met following comple- 
tion of tests. Since the vehicle must remain 
within a 12-foot-wide lane as a condition of the 
stopping distance tests, this will be a satisfactory 
demonstration of suspension system integrity. 

Effective date: September 1, 1974. Because 
of the necessity to allow manufacturers sufficient 
production leadtime, it is found for good cause 
shown that an effective date later than one year 
after issuance of this rule is in the public interest. 

In consideration of the foregoing, Title 49, 
Code of Federal Regulations, is amended by 
adding § 571.105a, Motor Vehicle Safety Stand- 
ard No. 105a, Hydraulic Brake System^., as set 
forth below. 

This notice is issued under the authority of 
sections 103 and 119 of the National Traffic and 



PART 571; S 105 —PRE 3 



MmHv«i S«ptMiib*r I, 19X4 

Motor Vehicle Safety Act of 1966 (16 U.S.C. Issued on : August 23, 1972. 

1392, 1407) and the delegation of authority frcHn Douglas W. Toms 

the Secretary of Transportation to the National Administrator 

Highway Traffic Safety Administrator, 49 CFR 37 F.R. 17970 

1.51. Septombar 2, 1972 



i 

PART 571; S 105 —PRE 4 



MmHv«i Saptambar 1, 1975 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105a 

Hydraulic Brak* Syttwm 
(Docket No. 70-27; Notic* 7) 



The purpose of this notice is to announce that 
the effective date of Motor Vehicle Safety Stand- 
ard No. 105a will be September 1, 1975. Full 
response to petitions for reconsideration is sched- 
uled for May 1, 1973. 

Standard No. 105a, Hydraulic Brake Syatema, 
was published on September 2, 1972 (37 F.R. 
17970 with corrections at 37 F.R. 19138) with an 
effective date of September 1, 1974. On Decem- 
ber 19, 1972, the NHTSA advised (37 F.R. 
27629) that it intended to issue a notice by Feb- 
ruary 1, 1973, in response to petitions for recon- 
sideration of the standard. The volume of the 
petitions received and the complexity of the 
issues involved are such that the agency has not 
found it possible to publish a full response to the 
petitions by the date indicated. 

The NHTSA has, however, decided to grant 
petitions requesting a delay in the effective date, 
to the extent of a one-year postponement. Peti- 
tioners have demonstrated to the satisfaction of 
the agency that because of critical lead-time 



problems the original effective date is impractic- 
able. The NHTSA believes that in the addi- 
tional year provided the industry will have 
sufficient time to increase the reliability of the 
systems that otherwise would have been incor- 
porated beginning September 1, 1974, with the 
result that consumers will be provided with brak- 
ing systems that have been optimized with re- 
spect to safety, performance, and cost. 

The full response and discussion of issues raised 
by the petitioners is planned for issuance by 
May 1, 1978. 

(Sec. 103, 119 P.L. 89-563, 80 Stat. 718, 15 
use 1392, 1407; delegation of authority at 49 
CFR 1.51). 

Issued on January 30, 1973. 

Douglas W. Toms 
Administrator 

38 F.R. 3047 
February 1. 1973 



PART 571; S 106 —PRE 6-6 



MmHv«i SapttmlMr 1, 197S 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105a 

Hydraulic Broke Systmm 

(Docket No. 70-27; Notico 7) 



The purpose of this notice is to announce that 
the effective date of Motor Vehicle Safety Stand- 
ard No. 105a will be September 1, 1975. Full 
response to petitions for reconsideration is sched- 
uled for May 1, 1973. 

Standard No. 105a, Hydraulic Brake Systems, 
was published on September 2, 1972 (37 F.R. 
17970 with corrections at 37 F.R. 19138) with an 
effective date of September 1, 1974. On Decem- 
ber 19, 1972, the NHTSA advised (37 F.R. 
27629) that it intended to issue a notice by Feb- 
ruary 1, 1973, in response to petitions for recon- 
sideration of the standard. The volume of the 
petitions received and the complexity of the 
issues involved are such that the agency has not 
found it possible to publish a full response to the 
petitions by the date indicated. 

The NHTSA has, however, decided to grant 
petitions requesting a delay in the effective date, 
to the extent of a one-year postponement. Peti- 
tioners have demonstrated to the satisfaction of 
the agency that because of critical lead-time 



problems the original effective date is impractic- 
able. The NHTSA believes that in the addi- 
tional year provided the industry will have 
sufficient time to increase the reliability of the 
systems that otherwise would have been incor- 
porated beginning September 1, 1974, with the 
result that consumers will be provided with brak- 
ing systems that have been optimized with re- 
spect to safety, performance, and cost. 

The full response and discussion of issues raised 
by the petitioners is planned for issuance by 
May 1, 1978. 

(Sec. 103, 119 P.L. 89-663, 80 Stat. 718, 15 
use 1392, 1407; delegation of authority at 49 
CFR 1.61). 

Issued on January 30, 1973. 

Douglas W. Toms 
Administrator 

38 F.R. 3047 
Fobrvary 1, 1973 



PART 671; S 106 —PRE 6-6 



Effective: Seplamber 1, 1 975 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105a 

Hydraulic Brake Systems 
(Docket No. 70-27; Notice 8) 



This notice responds to petitions for reconsid- 
eration of Motor Vehicle Safety Standard No. 
105a and amends the standard in certain re- 
spects, effective September 1, 1975. 

Federal Motor Vehicle Safety Standard No. 
105a, 49 CFR § 571.105a, was published on 
September 2, 1972 (37 F.R. 17970). Thereafter, 
pursuant to 49 CFR § 553.35 petitions for recon- 
sideration of the rule were received from many 
interested corporations. A discussion of the 
major issues raised by the petitions and their 
resolution follows. 

1. Policy. Several petitioners questioned the 
need for stringent braking requirements. The 
claim was made that NHTSA has shown neither 
a need based on accident data relating brake 
performance to deaths, injuries, or property 
damage, nor the benefits to be obtained from 
changed braking systems. Additionally, com- 
ments were received that most consumers could 
not utilize enhanced braking capabilities under 
most circumstances. Some also questioned the 
cost to implement the standard (allegedly $40 
an average per vehicle as a minimum, and up to 
$75 in some instances for passenger cars). 

The NHTSA does not agree with its critics on 
these policy issues. Braking system performance 
has consistently rated high on the safety critical- 
ity list. The dominance of the role of braking 
systems in accident avoidance maneuvers has 
long been recognized and undisputed. The im- 
portance of braking in motor vehicle safety is 
evidenced by the fact that of all vehicle defects 
which cause or contribute to accidents, brake 
failures lead the list. In the Consumer Infor- 
mation data on braking stopping distances pro- 
vided by the automobile manufacturers, the 
better performing vehicles are reported to stop 



from 60 mph in slightly more than one half the 
distance of the poorer performing vehicles. 
Large stopping distance differentials among ve- 
hicles operating in a common traffic stream are 
recognized as creating serious hazards to the 
motorist. 

Data have shown that in many accidents a 
more effective service brake system would have 
lessened the severity of the collision or possibly 
averted it. Existing vehicles in many instances 
do have good braking capabilities but require 
excessive control forces to utilize these capabili- 
ties. Many drivers are not able to exert these 
forces and hence do not utilize existing systems 
to the fullest. With reduced stopping distances 
within the specified pedal forces required by 
Standard No. 105a, it is the opinion of NHTSA 
that deaths, injuries, and property damage will 
be reduced. 

Since the requirements also specify that the 
stopping distances shall be achieved with the 
vehicle under control, stopping without locked 
wheels in a 12-foot-wide roadway lane, motorists 
will be afforded a greater opportunity to operate 
their brakes effectively in accident avoidance 
maneuvers. 

Cost estimates submitted by petitioners are in 
agreement with those of the NHTSA. Based 
upon the information received from petitioners 
and the changes made as a consequence thereof, 
however, it is the opinion of this agency that the 
cost of implementation will be reduced to a figure 
commensurate with the safety benefits expected 
to be derived. 

With respect to the performance levels speci- 
fied, the NHTSA has determined that the values 
are reasonable and do not exceed the inherent 
capabilities of any of the various vehicle classes. 



PART 571; S 105 —PRE 7 



Effective: September 1, 1975 



The values specified for vehicles other than pas- 
senger cars will considerably reduce the existing 
stopping distance differentials among vehicle 
classes. 

Several petitioners commented on what they 
considered to be a lack of consistency in perform- 
ance levels between vehicle types. For example, 
in the second effectiveness test, passenger cars, 
light trucks and heavy trucks have different per- 
formance requirements based upon weight and 
speed. Standard No. 105a was criticized also 
because the required stopping distances for heavy 
trucks with hydraulic brakes were more stringent 
than re(juirements for heavy trucks with air 
brakes (Standard No. 121, Air Brake Systems). 
It was argued that requirements should be the 
same for similar vehicles regardless of the type 
of brake system. Petitioners requested that par- 
tial failure system requirements, and require- 
ments for failed power units, be identical to 
those for air-braked vehicles. 

Other petitioners requested that emergency- 
type tests should allow locked wheels as in Stand- 
ard No. 121. Petitioners, in several instances, 
requested changes in light load test requirements 
for the various vehicles. These requests were 
based on differences in load conditions, inertia 
load differences in stopping, center of gravity 
locations, and braking balance differences. 

The standard has been amended to recognize 
the changes in performance due to vehicle weight 
differences, considering the effects of center of 
gravity location and weight shifts occurring 
during decelerations. Also, speed sensitivity 
effects have been recognized as occurring in all 
vehicles and appropriate modifications in re- 
quirements at the various test speeds have been 
made. Heavy vehicle requirements have been 
adjusted where appropriate to make them identi- 
cal to those existing in Standard No. 121. Some 
differences have been retained, however. For 
example, fade tests in Standard No. 105a are run 
on the vehicle in a road test as compared with a 
dynamometer test in Standard No. 121. Dyna- 
mometer tests were selected in Standard No. 121 
since vehicles used primarily in combinations are 
included in that standard. Compatibility be- 
tween vehicles (tractor and trailer) was consid- 
ered to be an important factor in the brake 



system evaluation and could most easily be de- 
termined on the dynamometer. 

Revisions to Standard 105a also have been 
made to allow wheel lockup on emergency-type 
tests such as spike stops, tests with failed power 
units, and partial system tests. Also, in the 
parking brake test, the limit of traction of the 
braked wheels is used in specifying parking 
brake system performance on a 30 per cent grade. 
There are no changes in parking braking .system 
requirements because of weight differences. The 
NHTSA is of the opinion that all vehicles, re- 
gardlass of weight class, are frequently parked 
in a lightly loaded condition and hence should 
be tested under this condition. 

2. Effective date. The NHTSA has previously 
announced an overall delay of one year in the 
effective date of Standard No. 105a (38 F.R. 
3097). 

Petitioners generally considered the original 
effective date of September 1, 1974, to be un- 
reasonable and impracticable. The earlier effec- 
tive date as it applied to trucks, buses and 
multipurpose passenger vehicles coincided with 
the same effective date for Standard No. 121, 
issued some time before Standard No. 105a. The 
air brake systems will generally have new and 
larger foundation brakes, new suspensions and 
other related components, antilock or brake pro- 
portioning systems and new split systems as well 
as controls. Hydraulic-braked vehicles require 
in most instances similar changes to meet 105a 
requirements. However, manufacturers and sup- 
pliers had prior commitments to concentrate 
much of their available manpower, equipment 
and facilities to the development of conforming 
air brake systems. These manpower, equipment, 
and facilities are generally the same required for 
the development of conforming hydraulic-braked 
vehicles, and thus the changes to hydraulic- 
braked vehicles cannot be made simultaneously 
with air brake system changes. In addition, 
sufficient recognition must be given to the lead- 
time necessary for application studies, production 
standardization in areas where this is possible, 
drawing and specification preparation, tooling 
design time and procurement, and establishing 
manufacturing facilities. In some instances, 
plant facilities must be built along with con- 



PART 571; S 105 —PRE 8 



Effective: September ), )97S 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105a 

Hydraulic Brake Systems 
(Docket No. 70-27; Notice 8) 



This notice responds to petitions for reconsid- 
eration of Motor Vehicle Safety Standard No. 
105a and amends the standard in certain re- 
spects, effective September 1, 1975. 

Federal Motor Vehicle Safety Standard No. 
105a, 49 CFR § 571.105a, was published on 
September 2, 1972 (37 F.R. 17970). Thereafter, 
pursuant to 49 CFR § 553.35 petitions for recon- 
sideration of the rule were received from many 
interested corporations. A discussion of the 
major issues raised by the petitions and their 
resolution follows. 

1. Policy. Several petitioners questioned the 
need for stringent braking requirements. The 
claim was made that NHTSA has shown neither 
a need based on accident data relating brake 
performance to deaths, injuries, or property 
damage, nor the benefits to be obtained from 
changed braking systems. Additionally, com- 
ments were received that most consumers could 
not utilize enhanced braking capabilities imder 
most circumstances. Some also questioned the 
cost to implement the standard (allegedly $40 
an average per vehicle as a minimum, and up to 
$75 in some instances for passenger cars). 

The NHTSA does not agree with its critics on 
these policy issues. Braking system performance 
has consistently rated high on the safety critical- 
ity list. The dominance of the role of braking 
systems in accident avoidance maneuvers has 
long been recognized and undisputed. The im- 
portance of braking in motor vehicle safety is 
evidenced by the fact that of all vehicle defects 
which cause or contribute to accidents, brake 
failures lead the list. In the Consumer Infor- 
mation data on braking stopping distances pro- 
vided by the automobile manufacturers, the 
better performing vehicles are reported to stop 



from 60 mph in slightly more than one half the 
distance of the poorer performing vehicles. 
Large stopping distance differentials among ve- 
hicles operating in a common traffic stream are 
recognized as creating serious hazards to the 
motorist. 

Data have shown that in many accidents a 
more effective service brake system would have 
lessened the severity of the collision or possibly 
averted it. Existing vehicles in many instances 
do have good braking capabilities but require 
excessive control forces to utilize these capabili- 
ties. Many drivers are not able to exert these 
forces and hence do not utilize existing systems 
to the fullest. With reduced stopping distances 
within the specified pedal forces required by 
Standard No. 105a, it is the opinion of NHTSA 
that deaths, injuries, and property damage will 
be reduced. 

Since the requirements also specify that the 
stopping distances shall be achieved with the 
vehicle under control, stopping without locked 
wheels in a 12-foot-wide roadway lane, motorists 
will be afforded a greater opportunity to operate 
their brakes effectively in accident avoidance 
maneuvers. 

Cost estimates submitted by petitioners are in 
agreement with those of the NHTSA. Based 
upon the information received from petitioners 
and the changes made as a consequence thereof, 
however, it is the opinion of this agency that the 
cost of implementation will be reduced to a figure 
commensurate with the safety benefits expected 
to be derived. 

With respect to the performance levels speci- 
fied, the NHTSA has determined that the values 
are reasonable and do not exceed the inherent 
capabilities of any of the various vehicle classes. 



PART 571; S 105 —PRE 7 



Effective: September 1, 1975 



The values specified for vehicles other than pas- 
senger cars will considerably reduce the existing 
stopping distance differentials among vehicle 
classes. 

Several petitioners commented on what they 
considered to be a lack of consistency in perform- 
ance levels between vehicle types. For example, 
in the second effectiveness test, passenger cars, 
light trucks and heavy trucks have different per- 
formance requirements based upon weight and 
speed. Standard No. 105a was criticized also 
because the required stopping distances for heavy 
trucks with hydraulic brakes were more stringent 
than recjuirements for heavy trucks with air 
brakes (Standard No. 121, Air Btvke Systems). 
It was argued that requirements should be the 
same for similar vehicles regardless of the type 
of brake system. Petitioners requested that par- 
tial failure system requirements, and require- 
ments for failed power units, be identical to 
those for air-braked vehicles. 

Other petitioners requested that emergency- 
type tests should allow locked wheels as in Stand- 
ard No. 121. Petitioners, in several instances, 
requested changes in light load test requirements 
for the various vehicles. These requests were 
based on differences in load conditions, inertia 
load differences in stopping, center of gravity 
locations, and braking balance differences. 

The standard has been amended to recognize 
the changes in performance due to vehicle weight 
differences, considering the effects of center of 
gravity location and weight shifts occurring 
during decelerations. Also, speed sensitivity 
effects have been recognized as occurring in all 
vehicles and appropriate modifications in re- 
quirements at the various test speeds have been 
made. Heavy vehicle requirements have been 
adjusted where appropriate to make them identi- 
cal to those existing in Standard No. 121. Some 
differences have been retained, however. For 
example, fade tests in Standard No. 105a are run 
on the vehicle in a road test as compared with a 
dynamometer test in Standard No. 121. Dyna- 
mometer tests were selected in Standard No. 121 
since vehicles used primarily in combinations are 
included in that standard. Compatibility be- 
tween vehicles (tractor and trailer) was consid- 
ered to be an important factor in the brake 



system evaluation and could mo.st easily be de- 
termined on the dynamometer. 

Revisions to Standard 105a also have been 
made to allow wheel lockup on emergency-type 
tests such as spike stops, tests with failed power 
units, and partial system tests. Also, in the 
parking brake test, the limit of traction of the 
braked wheels is used in specifying parking 
brake system performance on a 30 per cent grade. 
There are no changes in parking braking .system 
requirements because of weight differences. The 
NHTSA is of the opinion that all vehicles, re- 
gardless of weight class, are frequently parked 
in a lightly loaded condition and hence should 
be tested under this condition. 

2. Effective date. The NHTSA has previously 
announced an overall delay of one year in the 
effective date of Standard No. 105a (38 F.R. 
3097). 

Petitioners generally considered the original 
effective date of September 1, 1974, to be un- 
reasonable and impracticable. The earlier effec- 
tive date as it applied to trucks, buses and 
multipurpose passenger vehicles coincided with 
the same effective date for Standard No. 121, 
issued some time before Standard No. 105a. The 
air brake systems will generally have new and 
larger foundation brakes, new suspensions and 
other related components, antilock or brake pro- 
portioning systems and new split systems as well 
as controls. Hydraulic-braked vehicles require 
in most instances similar changes to meet 105a 
requirements. However, manufacturers and sup- 
pliers had prior commitments to concentrate 
much of their available manpower, equipment 
and facilities to the development of conforming 
air brake systems. These manpower, equipment, 
and facilities are generally the same required for 
the development of conforming hydraulic-braked 
vehicles, and thus the changes to hydraulic- 
braked vehicles cannot be made simultaneously 
with air brake system changes. In addition, 
sufficient recognition must be given to the lead- 
time necessary for application studies, production 
standardization in areas where this is possible, 
drawing and specification preparation, tooling 
design time and procurement, and establishing 
manufacturing facilities. In some instances, 
plant facilities must be built along with con- 



PART 571; S 105 —PRE 8 



EffKriva: S*pt«mb«r 1, 197S 



struction of development and test facilities. Pe- 
titioners also mentioned the significance of 
reduced product reliability if it is necessary to 
completely redesign entire vehicle lines simul- 
taneously. Additional problems that can arise 
are related to the capability of the manufactur- 
ers to train adequately technical personnel to 
assemble, service, and maintain the new vehicles. 

Several petitioners requested an extension of 
the effective date for vehicles other than passen- 
ger cars beyond September 1, 1975. International 
Harvester requested a date of September 1, 1976 
for these vehicles. Others would not predict a 
date on which they could meet the requirements. 

Several commenters stressed the fact that me- 
tallic, semi-metallic, or ceramic linings, considered 
exotic materials presently, would probably be 
required to meet Standard No. 10.5a as of Sep- 
tember 1, 1974. Resulting penalties would occur 
in cost (high wear, scoring, etc.) and poor or 
erratic performance under normal conditions. 

Comments were also received concerning four- 
wheel drive vehicles. Low volume and conse- 
quent high costs for necessary changes are prob- 
lems in this segment of the industry. Suppliers 
of components for these vehicles are allegedly 
reluctant to design and tool parts. In addition, 
manpower and facilities are not available for 
these jobs since most time and efforts must be 
utilized for the higher volume vehicles. An in- 
definite delay in an effective date for these ve- 
hicles has been requested. 

After careful evaluation of all the petitions, 
the NHTSA considered that good cause had been 
shown for a delay of one year in the effective 
date of the standard. But it has been determined 
that a further delay, either for the standard or 
for separate vehicle categories is not in the in- 
terest of motor vehicle safety, and those petitions 
for a further extension of time are denied. 

3. Definitions. Numerous comments were re- 
ceived on the definitions. In some instances 
amendments are made, in others, none. Clarifi- 
cations have been provided where they were 
requested. 

Questions relating to brake power assist units 
and brake power units have been raised. The 
distinction between the two Is that a brake power 
assist unit has a push-through capability, i.e., the 



operator can apply additional muscular effort and 
obtain braking action. A brake power unit does 
not have this capability. If power is lost, a 
driver cannot increase braking force by addi- 
tional muscular effort on the control. 

Some petitioners mentioned units which func- 
tion in both modes, i.e., as a brake power unit in 
one condition, and as a brake power assist unit 
in a second condition. For example, a unit may 
function as a brake power unit under normal 
operating conditions, but when a power failure 
occurs, it operates as a brake power assist unit. 
For purposes of compliance, the failed mode of 
operation would be the critical mode. Therefore, 
with inoperative power units, the test require- 
ments should be met depending on how the sys- 
tem, operates in the failed mode. The example 
discussed above would be tested as a brake power 
assist unit. 

The definition of "brake proportioning system" 
raised the question whether a fixed or variable 
system was intended. The term has been redes- 
ignated 'variable brake proportioning system" to 
clarify the agency's intent. 

The definition of "lightly loaded vehicle" does 
not specify an additional weight allowance for a 
load platform or body to be added to an incom- 
plete vehicle, but in the opinion of some peti- 
tioners it should. Since the standard applies to 
complete vehicles, a manufacturer must use his 
discretion in applying additional weight to in- 
complete vehicles, taking into account the result- 
ing changes in weight and center of gravity, 
when providing information on Standard No. 
105a to subsequent multistage vehicle manufac- 
turers. 

Some manufacturers questioned the adequacy 
of the test surface specification : the "skid num- 
ber" produced by American Society for Testing 
and Materials Method E-274, using a test trailer 
to measure the coefficient of friction. The com- 
plaint was made that the measurement results 
vary from one trailer to another, and vehicle 
performance results vary from one surface to 
another with supposedly the same skid number, 
on the order of 20 percent. It was also argued 
that the ASTM test was qualitatively inadequate, 
in that it measured sliding friction rather than 
peak or incipient friction. 



PART 571; S 105 —PRE 9 



EffecHv*: September 1, 1975 



The NHTSA does not accept these arguments. 
In the first place, it should be noted that thrust 
of the manufacturers' arguments is not only to 
abort this rulemaking, but to cast doubt on the 
validity of the existing braking standard. What- 
ever its shortcoming.., the ASTM test is the only 
one to the knowledge of th.is agency that provides 
an objective and quantitative measure of the 
frictional characteristics of a road surface, and 
no other was suggested by petitioners. The 
present passenger car braking standard incor- 
porates an SAE Recommended Practice (J843d) 
that specifies only a "dry, smooth, hard-surfaced 
roadway of Portland cement concrete (or other 
surface with equivalent coefficient of surface 
friction) that is free from loose materials," a far 
vaguer description. 

Furthermore, the NHTSA does not find the 
argument based on variations in test results to 
be persuasive. The variations of 15 and 20 per- 
cent cited are extreme figures. With carefully 
calibrated and controlled test instruments and 
conditions, as specified in the standard, evidence 
before this agency indicates that the normally 
experienced variations are much smaller. Manu- 
facturers have attempted to impose a criterion 
of perfect repeatability on the safety standards. 
Perfect repeatability, however, is an illusion. In 
the "real world" of materials testing, particularly 
of gross characteristics such as vehicle brakmg 
capability or crashworthiness, variation in re- 
sults is inevitable; the question is not whether, 
but how much, variation is acceptable. Ob- 
viously, the standard should be designed to rea- 
sonably minimize the variability of test results, 
from the standpoint both of manufacturing costs 
and of effective regulation. 

In this case, the ASTM method chosen was 
developed in 1965, and has been widely used since 
then for the purpose of vehicle performance 
testing. Moreover, it has been in force since 
1970 in a closely similar NHTSA regulation : 
the Consumer Information regulation on Vehicle 
Stopping Distance (49 CFR 575.101), under 
which manufacturers have been required to test 
their vehicles' stopping-distance capabilities, and 
report them to consumers and to the NHTSA. 
The same statutory penalties have applied to a 
failure to meet these reported stopping distances 
when tested by the government as would apply 



to a failure to meet the stopping distance re- ^ 
quired by a standard. In light of these factors, 
the arguments that the method for specifying 
the test surface is inadequate are found to be 
without merit. 

The NHTSA also rejects the suggestion by the 
Recreational Vehicle Institute that this agency 
should supply or measure the test surface, be- 
cause of the limited capabilities of motor home 
manufacturers. The clearly intended result of 
the National Traffic and Motor Vehicle Safety 
Act is that the private sector should bear the 
cost of regular conformity and certification test- 
ing. There is no requirement that each vehicle 
manufacturer have his own measured test track. 
Small manufacturers can have their vehicles 
tested by contract with testing companies; they 
can use their trade associations to arrange for 
use of measured test tracks in convenient regional 
locations; or they can work with the chassis 
manufacturer and use his test results. 

The sudden application of force in a "spike 
stop" is 200 pounds applied in 0.08 second. 
Chrysler Corporation suggested a "band" of m 
0.05-0.20 seconds as permitted in SAE Recom- fl 
mended Practice J229 Service Brake Stnu:tural 
Integrity Test Procedure, March 1971. The 
purpose and legal significance of a test condition 
in a Federal motor vehicle safety standard are 
different from those of an industry test practice, 
and a band or tolerance as requested by Chrysler 
is inappropriate and unnecessary in the former. 
Assuming that a faster application is more de- 
manding of vehicle performance, Chrysler in 
effect has a band from to 0.08 second for its 
tests, which should be designed to show that the 
vehicle is capable of meeting the requirements 
with spike stops of 0.08 second. 

The definition of "stopping distance" varied 
from the notice of proposed rulemaking in that 
the phrase "start of the brake application" was 
changed to "point of application of force to the 
brake control." Wagner Electric Co. considers 
the modified definition as more stringent since, 
in its view, the notice allowed both "force" and 
"movement" while the amendment allows only 
the former. The NHTSA disagrees with Wag- 
ner. Both versions refer purely to the brake 
pedal, and not to more remote parts of the brake M 



PART 571; S 105 —PRE 10 



Effcctiv*: September 1, 1975 



struction of development and test facilities. Pe- 
titioners also mentioned the significance of 
reduced product reliability if it is necessary to 
completely redesign entire vehicle lines simul- 
taneously. Additional problems that can arise 
are related to the capability of the manufactur- 
ers to train adequately technical personnel to 
assemble, service, and maintain the new vehicles. 

Several petitioners requested an extension of 
the effective date for vehicles other than passen- 
ger cars beyond September 1, 1975. International 
Harvester requested a date of September 1, 1976 
for these vehicles. Others would not predict a 
date on which they could meet the requirements. 

Several commenters stressed the fact that me- 
tallic, semi-metallic, or ceramic linings, considered 
exotic materials presently, would probably be 
required to meet Standard No. 105a as of Sep- 
tember 1, 1974. Resulting penalties would occur 
in cost (high wear, scoring, etc.) and poor or 
erratic performance under normal conditions. 

Comments were also received concerning four- 
wheel drive vehicles. Low volume and conse- 
quent hi<^h costs for necessary changes are prob- 
lems in this segment of the industry. Suppliers 
of components for these vehicles are allegedly 
reluctant to design and tool parts. In addition, 
manpower and facilities are not available for 
these jobs since most time and efforts must be 
utilized for the higher volume vehicles. An in- 
definite delay in an effective date for these ve- 
hicles has been requested. 

After careful evaluation of all the petitions, 
the NHTSA considered that good cause had been 
shown for a delay of one year in the effective 
date of the standard. But it has been determined 
that a further delay, either for the standard or 
for separate vehicle categories is not in the in- 
terest of motor vehicle safety, and those petitions 
for a further extension of time are denied. 

3. Definitions. Numerous comments were re- 
ceived on the definitions. In some instances 
amendments are made, in others, none. Clarifi- 
cations have been provided where they were 
requested. 

Questions relating to brake power assist units 
and brake power units have been raised. The 
distinction between the two is that a brake power 
assist unit has a push-through capability, i.e., the 



operator can apply additional muscular effort and 
obtain braking action. A brake power unit does 
not have this capability. If power is lost, a 
driver cannot increase braking force by addi- 
tional muscular effort on the control. 

Some petitioners mentioned units which func- 
tion in both modes, i.e., as a brake power unit in 
one condition, and as a brake power assist unit 
in a second condition. For example, a unit may 
function as a brake power unit under normal 
operating conditions, but when a power failure 
occurs, it operates as a brake power assist unit. 
For purposes of compliance, the failed mode of 
operation would be the critical mode. Therefore, 
with inoperative power units, the test require- 
ments should be met depending on how the sys- 
tem operates in the failed mode. The example 
discussed above would be tested as a brake power 
assist unit. 

The definition of "brake proportioning system" 
raised the question whether a fixed or variable 
system was intended. The term has been redes- 
ignated 'variable brake proportioning system" to 
clarify the agency's intent. 

The definition of "lightly loaded vehicle" does 
not specify an additional weight allowance for a 
load platform or body to be added to an incom- 
plete vehicle, but in the opinion of some peti- 
tioners it should. Since the standard applies to 
complete vehicles, a manufacturer must use his 
discretion in applying additional weight to in- 
complete vehicles, taking into account the result- 
ing changes in weight and center of gravity, 
when providing information on Standard No. 
105a to subsequent multistage vehicle manufac- 
turers. 

Some manufacturers questioned the adequacy 
of the test surface specification : the "skid num- 
ber" produced by American Society for Testing 
and Materials Method E-274, using a test trailer 
to measure the coefficient of friction. The com- 
plaint was made that the measurement results 
vary from one trailer to another, and vehicle 
performance results vary from one surface to 
another with supposedly the same skid number, 
on the order of 20 percent. It was also argued 
that the ASTM test was qualitatively inadequate, 
in that it measured sliding friction rather than 
peak or incipient friction. 



PART 571; S 105 —PRE 9 



Effacllvo: Saplamber 1, 1975 



The NHTSA does not accept these arguments. 
In the first place, it should be noted that thrust 
of the manufacturers' arguments is not only to 
abort this rulemaking, but to cast doubt on the 
validity of the existing braking standard. What- 
ever its shortcoming", tiie ASTM test is the only 
one to the knowledge of tiiis agency that provides 
an objective and quantitative measure of the 
frictional characteristics of a road surface, and 
no other was suggested by petitioners. The 
present passenger car braking standard incor- 
porates an SAE Recommended Practice (J843d) 
that specifies only a "dry, smooth, hard-surfaced 
roadway of Portland cement concrete (or other 
surface with equivalent coefficient of surface 
friction) that is free from loose materials," a far 
vaguer description. 

Furthermore, the NHTSA does not find the 
argument based on variations in test results to 
be persuasive. The variations of 15 and 20 per- 
cent cited are extreme figures. With carefully 
calibrated and controlled test instruments and 
conditions, as specified in the standard, evidence 
before this agency indicates that the normally 
experienced variations are much smaller. Manu- 
facturers have attempted to impose a criterion 
of perfect repeatability on the safety standards. 
Perfect repeatability, however, is an illusion. In 
the "real world" of materials testing, particularly 
of gross characteristics such as vehicle brakmg 
capability or crashworthiness, variation in re- 
sults is inevitable; the question is not whether, 
but how much, variation is acceptable. Ob- 
viously, the standard should be designed to rea- 
sonably minimize the variability of test results, 
from the standpoint both of manufacturing costs 
and of effective regulation. 

In this case, the ASTM method chosen was 
developed in 1965, and has been widely used since 
then for the purpose of vehicle performance 
testing. Moreover, it has been in force since 
1970 in a closely similar NHTSA regulation: 
the Consumer Information regulation on Vehicle 
Stopping Distance (49 CFR 575.101), under 
which manufacturers have been required to test 
their vehicles' stopping-distance capabilities, and 
report them to consumers and to the NHTSA. 
The same statutory penalties have applied to a 
failure to meet these reported stopping distances 
when tested by the government as would apply 



to a failure to meet the stopping distance re- 
quired by a standard. In light of these factors, 
the arguments that the method for specifying 
the test surface is inadequate are found to be 
without merit. 

The NHTSA also rejects the suggestion by the 
Recreational Vehicle Institute that this agency 
should supply or measure the t«st surface, be- 
cause of the limited capabilities of motor home 
manufacturers. The clearly intended result of 
the National Traffic and Motor Vehicle Safety 
Act is that the private sector should bear the 
cost of regular conformity and certification test- 
ing. There is no requirement that each vehicle 
manufacturer have his own measured test track. 
Small manufacturers can have their vehicles 
tested bj' contract with testing companies; they 
can use their trade associations to arrange for 
use of measured test tracks in convenient regional 
locations; or they can work with the chassis 
manufacturer and use his test results. 

The sudden application of force in a "spike 
stop" is 200 pounds applied in 0.08 second. 
Chrysler Corporation suggested a "band" of 
0.05-0.20 seconds as permitted in SAE Recom- 
mended Practice J229 Service Brake Structural 
Integrity Test Procedure, March 1971. The 
purpose and legal significance of a test condition 
in a Federal motor vehicle safety standard are 
different from those of an industry test practice, 
and a band or tolerance as requested by Chrysler 
is inappropriate and unnecessary in the former. 
Assuming that a faster application is more de- 
manding of vehicle performance, Chrysler in 
effect has a band from to 0.08 second for its 
tests, which should be designed to show that the 
vehicle is capable of meeting the requirements 
with spike stops of 0.08 second. 

The definition of "stopping distance" varied 
from the notice of proposed rulemaking in that 
the phrase "start of the brake application" was 
changed to "point of application of force to the 
brake control." Wagner Electric Co. considers 
the modified definition as more stringent since, 
in its view, the notice allowed both "force" and 
"movement" while the amendment allows only 
the former. The NHTSA disagrees with Wag- 
ner. Both versions refer purely to the brake 
pedal, and not to more remote parts of the brake 



PART 671; S 105 —PRE 10 



Effactiv*: S*pl*mb*r 1, I97S 



system. This agency is unaware of any measur- 
able difference in time between the introduction 
of force to the pedal and the initiation of pedal 
movement, and Wagner has supplied no evidence 
to the contrary. The modified wording has been 
adopted for purposes of clarity. 

General Motors objected to stopping distances 
as performance requirements, and expressed its 
views that deceleration rates provide more ob- 
jective performance criteria. This represented a 
departure from GM's previous views that build- 
up and maintenance of a fixed deceleration 
depended upon varying driver skills, affecting 
reproducibility. The variety in driver skills is 
one reason the NHTSA considers measurement 
of a specified distance more desirable than main- 
tenance of a fixed deceleration rate. Insertion 
of a fixed build-up time would introduce a com- 
plication. The stopping distances specified do 
not include a fixed build-up time but instead 
allow use of various characteristics, including 
greater or lesser build-up times, as long as the 
vehicle does not exceed the stopping distance 
specified. A specified maximum (but not fixed) 
build-up time is used in fade tests where decele- 
rations are specified. Further, the distances 
expressed in Standard No. 105a are maximum 
distances, and manufacturers will necessarily 
design their vehicles to perform with a margin 
within those limits, thus reducing problems of 
objective measurement. 

4. Required stopping distances and pedal con- 
trol forces. The stopping distance values, in 
most instances, were considered by petitioners to 
require redesigned braking systems. In some 
cases, larger brake systems would be required, 
incorporating front disc brakes with power assist 
and larger rear drum brakes. Other vehicles, 
particularly trucks, buses, and multipurpose pas- 
senger vehicles, would require the addition of 
antilock systems or brake proportioning systems, 
along with new types of split systems (or com- 
pletely redundant systems). These systems, it 
is alleged, would be required to meet the full 
system effectiveness and the partial system effec- 
tiveness requirements. 

The 30 mph and maximum speed stopping 
distances were considered too stringent by most 
petitioners. The very short stops involved, along 



with the buildup or actuation time necessary, 
were the main problems in the 30-mph tests. 
The problem of the speed sensitivity of lining 
materials was the main factor noted in comments 
relating to the high speed and maximum speed 
tests. 

For first effectiveness test, recommended 
changes in stopping distances ranged at 30 mph 
from no increase to an increase of 9 feet for 
passenger cars, 7 feet for light trucks, and 20 
feet for heavy trucks. At 60 mph, requests for 
increases of up to 17 feet for passenger cars, 
7 feet for light trucks, and 75 feet for heavy 
trucks were received. Two petitioners suggested 
deleting heavy truck requirements, either to be 
consistent with Standard No. 121 or until "more 
realistic data" was available. 

The second through fourth effectiveness tests 
were more severely criticized by petitioners. 
Several suggested that fourth effectiveness test 
values be increased to at least those used in the 
first effectiveness tests (involving increases of 
5, 7 and 10 feet at 30 mph, and changes of 20, 
26, and 32' feet at 60 mph, for passenger cars, 
light trucks and heavy trucks, respectively). 
Several commenters recommended deletion of 
tests at speeds greater than 80 mph. For light 
and heavy trucks, maximum speeds of 60 mph 
to 80 mph were recommended. 

Certain modifications in stopping distances 
and test speeds have been made in response to 
these comments. The maximum test speed for a 
vehicle with a GVWR that exceeds 10,000 pounds 
has been reduced from 80 mph to 60 mph. The 
maximum test speed will be 100 mph, specified 
only for those passenger cars which attain a 
speed of 104 mph or greater in 2 miles. If the 
speed that a passenger car is capable of attaining 
in 2 miles is from 99 to 104 mph, its maximum 
test speed will be 95 mph. Intermediate test 
speeds between 80 and 95 mph, and 60 and 80 
mph have also been eliminated for all vehicles; 
thus if a vehicle's top speed is from 84 to 99 
mph, its top test speed is 80 mph; if the top 
speed is from 64 to 84 mph, its top test speed is 
60 mph. Stopping distances have been increased 
slightly in most instances from those previously 
required; an example is the second effectiveness 
test where the 60-mph stopping distance for pas- 



PART 571; S 105 —PRE 11 



EffKllv*: Saptombtr 1, 1975 



senger cars at GVIVR will be 204 feet rather 
than 194. Under partial failure conditions at 
the same speed, the stopping distance for pas- 
senger cars has been increased from 431 to 456 
feet. 

Standard No. 105a required stops to be made 
at pedal forces that varied from 15 to 100 pounds 
at stops from 30 mph, to 20 to 150 pounds at 
stops from 65 mph or higher. Pedal control 
force values were objected to and requests for 
changes were made, ranging from an increase 
at 30 mph to 120 pounds to an across the board 
increase to 150 pounds maximum for all tests. 
Petitions were based generally on the need either 
to allow higher pedal forces to reduce brake 
sensitivity or to provide a simple single value 
for all tests. A change to allow 200 pounds of 
maximum pedal force on parking brake tests for 
light trucks was also requested. Several peti- 
tioners also requested modifications in fade re- 
covery test pedal force values. 

The NHTSA considers that most of these re- 
quests are meritorious. The standard is being 
amended to specify a uniform force range of 
16 to 150 pounds for all stops that must be made 
within required stopping distances, and this will 
be expressed as a test condition in paragraph S6. 
However, the parking brake test pedal forces 
must, in the opinion of the NHTSA remain 
uniform at 125 and 90 pounds (foot and hand) 
and the petition on this point is denied. General 
Motors requested a force for the 5th (final) fade 
recovery stop that is within plus 50 pounds and 
minus 5 pounds or minus 40 percent (whichever 
is greater) of the average control force for the 
baseline check. These values are considered too 
broad. Some relief is deemed warranted, how- 
ever, and Japan Automobile Manufacturers As- 
sociation's suggested value of minus 10 pounds 
has been adopted. 

6. Inoperative power units. In addition to the 
requests for clarification between brake power 
assist units and brake power units petitioners 
requested changes in requirements that would 
recognize the reserve capabilities that have been 
designed into the inoperative mode of some power 
systems. These petitions have been granted, and 
tests with an inoperative brake power unit or 
power assist unit have been modified to allow 



optional utilization of reserve capabilities in 
stopping. Under the optional procedure a ve- 
hicle makes a series of stops from 60 mph at 
specified decelerations when the inoperative unit 
is not initially depleted of all reserve capability 
and in a final stop within 554 feet when the unit 
has been depleted of its reserve. 

6. Fade and recovery requirements. Standard 
No. 105a required that vehicles with a GVWR 
of 10,000 pounds or less demonstrate fade re- 
sistance in two fade and recovery tests of 10 and 
15 stops each from 60 mph at 15 fpsps. 

Fade and recovery requirements were consid- 
ered extremely stringent by petitioners. Several 
petitioners suggested a reversion to the existing 
requirements with minor modifications. Others 
suggested changes in test weights. Most were 
willing to accept the 150-pound pedal force 
limitation if other modifications proposed were 
acceptable. GM recommended that two different 
fade test procedures be adopted, the first simu- 
lating a mountain type fade test at GVWR with 
increased distance intervals, and the second being 
similar to that adopted except at a reduced test 
load. 

These petitions have been deemed in large 
part to have merit, and the two fade tests will 
be revised to consist of 5 and 10 fade stops at 
15 fpsps, each followed by an additional 5 stops 
at the maximum deceleration attainable between 
5 and 15 fpsps. The fade test requirements for 
vehicles with a GVWR in excess of 10,000 pounds 
remains unchanged. However, no procedure 
simulating mountain descents has been developed, 
and GM's request is denied. International 
Harvester, in the fade test procedure, requested 
that the time to attain the required deceleration 
presently 1 second, be increased to 5 seconds. 
This request is denied, since an increase has been 
found unnecessary. 

7. Water recovery. GM petitioned for sub- 
stantial changes in the water recovery test, ask- 
ing relocation within the test sequence, modified 
control forces, and increassed number of recovery 
stops for heavy trucks. None of these requests 
has been found to have merit. A change in se- 
quence would necessitate reevaluation of the 
effect of the standard with a possible consequent 
further delay in the effective date. 



PART 671; S 105 —PRE 12 



Effacliv*: Scptamber 1, 1975 



system. This agency is unaware of any measur- 
able difTerence in time between the introduction 
of force to the pedal and the initiation of pedal 
movement, and Wagner has supplied no evidence 
to the contrary. The modified wording has been 
adopted for purposes of clarity. 

General Motors objected to stopping distances 
as performance requirements, and expressed its 
views that deceleration rates provide more ob- 
jective performance criteria. This represented a 
departure from GM's previous views that build- 
up and maintenance of a fixed deceleration 
depended upon varying driver skills, affecting 
reproducibility. The variety in driver skills is 
one reason the NHTSA considers measurement 
of a specified distance more desirable than main- 
tenance of a fixed deceleration rate. Insertion 
of a fixed build-up time would introduce a com- 
plication. The stopping distances specified do 
not include a fixed build-up time but instead 
allow use of various characteristics, including 
greater or lesser build-up times, as long as the 
vehicle does not exceed the stopping distance 
specified. A specified maximum (but not fixed) 
build-up time is used in fade tests where decele- 
rations are specified. Further, the distances 
expressed in Standard No. 105a are maximum 
distances, and manufacturers will necessarily 
design their vehicles to perform with a margin 
within those limits, thus reducing problems of 
objective measurement. 

4. Required stopping distances and pedal con- 
trol forces. The stopping distance values, in 
most instances, were considered by petitioners to 
require redesigned braking systems. In some 
cases, larger brake systems would be required, 
incorporating front disc brakes with power assist 
and larger rear drum brakes. Other vehicles, 
particularly trucks, buses, and multipurpose pas- 
senger vehicles, would require the addition of 
antilock systems or brake proportioning systems, 
along with new types of split systems (or com- 
pletely redundant systems). These systems, it 
is alleged, would be required to meet the full 
system effectiveness and the partial system effec- 
tiveness requirements. 

The 30 mph and maximum speed stopping 
distances were considered too stringent by most 
petitioners. The very short stops involved, along 



with the buildup or actuation time necessary, 
were the main problems in the 30-mph tests. 
The problem of the speed sensitivity of lining 
materials was the main factor noted in comments 
relating to the high speed and maximum speed 
tests. 

For first effectiveness test, recommended 
changes in stopping distances ranged at 30 mph 
from no increase to an increase of 9 feet for 
passenger cars, 7 feet for light trucks, and 20 
feet for heavy trucks. At 60 mph, requests for 
increases of up to 17 feet for passenger cars, 
7 feet for light trucks, and 75 feet for heavy 
trucks were received. Two petitioners suggested 
deleting heavy truck requirements, either to be 
consistent with Standard No. 121 or until "more 
realistic data" was available. 

The second through fourth effectiveness tests 
were more severely criticized by petitioners. 
Several suggested that fourth effectiveness test 
values be increased to at least those used in the 
first effectiveness tests (involving increases of 
5, 7 and 10 feet at 30 mph, and changes of 20, 
26, and 32" feet at 60 mph, for passenger cars, 
light trucks and heavy trucks, respectively). 
Several commenters recommended deletion of 
tests at speeds greater than 80 mph. For light 
and heavy trucks, maximum speeds of 60 mph 
to 80 mph were recommended. 

Certain modifications in stopping distances 
and test speeds have been made in response to 
these comments. The maximum test speed for a 
vehicle with a GVWR that exceeds 10,000 pounds 
has been reduced from 80 mph to 60 mph. The 
maximum test speed will be 100 mph, specified 
only for those passenger cars which attain a 
speed of 104 mph or greater in 2 miles. If the 
speed that a passenger car is capable of attaining 
in 2 miles is from 99 to 104 mph, its maximum 
test speed will be 95 mph. Intermediate test 
speeds between 80 and 95 mph, and 60 and 80 
mph have also been eliminated for all vehicles; 
thus if a vehicle's top speed is from 84 to 99 
mph, its top test speed is 80 mph; if the top 
speed is from 64 to 84 mph, its top test speed is 
60 mph. Stopping distances have been increased 
slightly in most instances from those previously 
required; an example is the second effectiveness 
test where the 60-mph stopping distance for pas- 



PART 571; S 105 —PRE 11 



EffKtiv*: September 1, 1975 



senger cars at GVAVR will be 204 feet rather 
than 194. Under partial failure conditions at 
the same speed, the stopping distance for pas- 
jsnger cars has been increased from 431 to 456 
feet. 

Standard No. 105a required stops to be made 
at pedal forces that varied from 15 to 100 pounds 
at stops from 30 mph, to 20 to 150 pounds at 
stops from 65 mph or higher. Pedal control 
force values were objected to and requests for 
changes were made, ranging from an increase 
at 30 mph to 120 pounds to an across the board 
increase to 150 pounds maximum for all tests. 
Petitions were based generally on the need either 
to allow higher pedal forces to reduce brake 
sensitivity or to provide a simple single value 
for all tests. A change to allow 200 pounds of 
maximum pedal force on parking brake tests for 
light trucks was also requested. Several peti- 
tioners also requested modifications in fade re- 
covery test pedal force values. 

The NHTSA considers that most of these re- 
quests are meritorious. The standard is being 
amended to specify a uniform force range of 
15 to 150 pounds for all stops that must be made 
within required stopping distances, and this will 
be expressed as a test condition in paragraph S6. 
However, the parking brake teat pedal forces 
must, in the opinion of the NHTSA remain 
uniform at 125 and 90 pounds (foot and hand) 
and the petition on this point is denied. General 
Motors requested a force for the 5th (final) fade 
recovery stop that is within plus 50 pounds and 
minus 5 pounds or minus 40 percent (whichever 
is greater) of the average control force for the 
baseline check. These values are considered too 
broad. Some relief is deemed warranted, how- 
ever, and Japan Automobile Manufacturers As- 
sociation's suggested value of minus 10 pounds 
has been adopted. 

5. Inoperative power units. In addition to the 
requests for clarification between brake power 
assist units and brake power units petitioners 
requested changes in requirements that would 
recognize the reserve capabilities that have been 
designed into the inoperative mode of some power 
systems. These petitions have been granted, and 
tests with an inoperative brake power unit or 
power assist unit have been modified to allow 



optional utilization of reserve capabilities in 
stopping. Under the optional procedure a ve- 
hicle makes a series of stops from 60 mph at 
specified decelerations when the inoperative unit 
is not initially depleted of all reserve capability 
and in a final stop within 554 feet when the unit 
has been depleted of its reserve. 

6. Fade and recovery requirements. Standard 
No. 105a required that vehicles with a GVWR 
of 10,000 pounds or less demonstrate fade re- 
sistance in two fade and recovery tests of 10 and 
15 stops each from 60 mph at 15 fpsps. 

Fade and recovery requirements were consid- 
ered extremely stringent by petitioners. Several 
petitioners suggested a reversion to the existing 
requirements with minor modifications. Others 
suggested changes in test weights. Most were 
willing to accept the 150-pound pedal force 
limitation if other modifications proposed were 
acceptable. GM recommended that two different 
fade test procedures be adopted, the first simu- 
lating a mountain type fade test at GVWR with 
increased distance intervals, and the second being 
similar to that adopted except at a reduced test 
load. 

These petitions have been deemed in large 
part to have merit, and the two fade tests will 
be revised to consist of 5 and 10 fade stops at 
15 fpsps, each followed by an additional 5 stops 
at the maximum deceleration attainable between 
5 and 15 fpsps. The fade test requirements for 
vehicles with a GVWR in excess of 10,000 pounds 
remains unchanged. However, no procedure 
simulating mountain descents has been developed, 
and GM's request is denied. International 
Harvester, in the fade test procedure, requested 
that the time to attain the required deceleration 
presently 1 second, be increased to 5 seconds. 
This request is denied, since an increase has been 
found unnecessary. 

7. Water recovery. GM petitioned for sub- 
stantial changes in the water recovery test, ask- 
ing relocation within the test sequence, modified 
control forces, and increassed number of recovery 
stops for heavy trucks. None of these requests 
has been found to have merit. A change in se- 
quence would necessitate reevaluation of the 
effect of the standard with a possible consequent 
further delay in the effective date. 



PART 571; S 105 —PRE 12 



Effactlv*: S*pl«mbtr I, 197S 



8. Spike stops. Witli regard to the spike stop 
requirements, Bendix requested that the stopping 
distance for the effectiveness (check) stops be the 
equivalent of the first effectiveness test rather 
than that of the otlier effectiveness tests. The 
request has merit, and the stopping distance re- 
quirements of the first effectiveness test have 
been adopted. 

GM requested that for the spike stop test 
manufacturers be allowed to use separate vehicles 
not used in the other tests, while Harvester re- 
quested a reduction in stopping speed from 60 
mph to 30 mph. Because of the changes in stop- 
ping distance that have been adopted, no further 
relief is deemed necessary and the petitions are 
denied. 

9. Parking brake systems. The parking brake 
system requirements, particularly in the lightly 
loaded vehicle condition, were objected to as 
violating the laws of physics. As mentioned 
earlier, petitioners generally requested inclusion 
of a "limit of traction" condition. Vehicles with 
a great range of loading conditions are allegedly 
incapable of holding on grades specified in the 
requirements (20 percent or 30 percent). Par- 
ticular stress was placed oi brake holding capa- 
bility on a 75 skid number surface. One com- 
menter requested that the same requirements 
apply to all vehicles, claiming it unrealistic for 
light vehicles to meet the 30 percent grade re- 
quirement while heavy vehicles only had to meet 
a 20 percent requirement, and suggested use of a 
Swedish standard (16 percent grade, 110 pounds 
of foot brake force, 88 pounds of hand brake 
force). Ford requested allowance for use of a 
multistroke parking brake application. Ameri- 
can Motors Corporation requested reinstatement 
of existing Standard No. 105 requirements. GM 
and Chrysler objected to the requirement that 
the parking brake be of a "friction type" which 
they considered design restrictive, prohibiting 
other acceptable parking brake systems. 

The parking brake system test remains sub- 
stantially as adopted. The performance require- 
ments have been found feasible with present 
technology. A multistroke application is permis- 
sible, and limit of traction language has been 
added to the 30 percent grade requirement, to 
eliminate the irrelevant problem of tire slippage. 



The requirement for a friction-type parking 
brake is also retained. In a case of complete 
loss of service brake capability, a friction-type 
parking brake furnishes a residual stopping 
capability for a moving vehicle that is absent in 
a pawl-type system (such as the "park" position 
transmission stop). If the phrase "friction 
type" appears design restrictive of other types 
of parking brake systems that would provide 
equivalent capability, this agency will be recep- 
tive to suggestions for substitute language, with 
adequate supporting information. 

Wagner petitioned for deletion of the parking 
brake test with the vehicle at lightly loaded 
weight. This request is denied as the NHTSA 
believes that vehicles are frequently parked in a 
lightly loaded condition, and that a test should 
therefore be run at this vehicle weight. 

10. Indicator lamps. The standard has been 
amended so that indicator lamps may now be 
activated as a check of lamp function when the 
ignition is in the on position and the engine is 
not running, or in any position between on and 
start that is designated by the manufacturer as 
a check position. Ford petitioned that the brake 
fluid level indicator be deleted, but its request 
is denied as the NHTSA has determined that a 
warning should be provided in the event of slow 
leaks. Conversely, Mercedes-Benz of North 
America petitioned for deletion of the pressure 
differential warning, alleging that the fluid level 
indicator is sufficient. This, too, is denied, as the 
fluid level indicator will not indicate pressure 
failure until the fluid is at the level specified for 
a warning, an entirely different function. Sev- 
eral petitions asked that the 200-psi brake fluid 
pressure level be adopted (this had been proposed 
in Notice 1 for measurement at master or slave 
cylinder outlets), and these petitions have been 
granted. In response to several petitions, the 
illumination provided when an indicator lamp is 
activated may be flashing as well as steady- 
burning. 

11. Reservoirs. In the requirements for the 
master cylinder reservoir, clarifications have been 
provided in the determination of a fully worn, 
fully applied lining position. Reservoir labeling 
has been modified to require color contrasts of 
printed labels only, the contrast in lettering and 



PART 571 ; S 105 —PRE 13 



Eff*cliva: SspUmber 1, 1975 



background on stamped or embossed labels 
deemed a sufficient contrast in those instances. 
GM asserted that the reservoir capacity require- 
ments were unnecessary in light of the require- 
ment for a fluid level indicator, and petitioned 
that the requirements be deleted. The petition 
is denied; the volume requirements are necessary 
to provide sufficient fluid for a full range of 
brake travel. 

12. Test conditions. The specified test load of 
50 to 725 pounds per cubic foot has been refined 
by assigning density distribution to various ve- 
hicle areas, for example 50 to 125 pounds per 
cubic foot in the seating area of all vehicles. 
Several manufacturers requested that the trans- 
mission selector control be in gear during all 
test decelerations, alleging that the neutral posi- 
tion is not representative of consumer usage. 
These requests are denied. Deceleration in gear 
by adding driveline drag masks the true effec- 
tiveness of the brake system. Comments were 
also directed to the prohibition against lockups, 
generally alleging inconsistency with Standard 
No. 121. These comments had merit, and the 
test condition has been amended to allow lockups 
during spike stops, partial failure stops and in- 
operative brake power or power assist unit stops. 
On the other hand, a request to allow more than 
one locked wheel is denied. Provision has been 
made for installation of a second thermocouple 
at the beginning of the test sequence if the lining 
wear is expected to reach a point causing the 
first thermocouple to contact the metal rubbing 
surface of a drum or rotor. Since the brake 
control forces have been modified to a uniform 
range of 15 to 150 pounds, except as otherwise 
specified, control forces have been added to the 
list of test conditions. 

13. Test procedures and sequence. Most Amer- 
ican manufacturers and suppliers commented on 
the severity of the sequential procedure, with 
arguments of the following nature: The high 
speed effectiveness tests early in the sequence 
result in changes in lining characteristics which, 
in turn, affect the capability of the vehicles to 
comply with parking brake and partial systems 
requirements. Since no reburnish is allowed 
until after the first fade test, additional lining 
deterioration occurs as light load tests and fade 



tests are run. When final effectiveness tests are 
run, organic linings (normally used in today's 
vehicles) have deteriorated appreciably. This 
sequential testing, without reconditioning at in- 
tervals, results in brake torque balance changes 
as the test sequence progresses. To offset these 
changes and to enable a vehicle to go through 
compliance tests satisfactorily, many vehicles 
would have to be designed with an initial high 
gear brake capacity. This results in an unsafe 
early rear brake lockup, particularly at the initial 
light load test. As the sequence progresses, brake 
balance shifts toward a more reasonable balance, 
where all wheels approach lockup at or near 
same point. A brake balance which is designed 
initially for GVWR test conditions to meet 
Standard 105a requirements, would be dangerous 
to consumers for normal usage at 2 to 3 passenger 
loads due to rear wheel lockup and resultant 
uncontrollable skids. Recommendations by pe- 
titioners generally favored less testing at GVWR, 
reduced maximum test speeds, lessened fade re- 
quirements, and lessened final effectiveness re- 
quirements. The various changes would allow 
design of a brake system more suitable to normal 
consumer usage rather than the usage encoimtered 
in 105a tests. Ford recommended some changes 
in sequence but submitted a procedure incorporat- 
ing the 105a sequence with modified performance 
requirements. GM suggested a drastically re- 
vised sequence along with reduced performance 
requirements. Several petitioners recommended 
additional burnish stops and adjustments at 
several points, generally after each effectiveness 
series. Ford proposed a 200 stop additional 
burnish after the second fade test. 

In responding to petitions for reconsideration, 
the NHTSA has not modified the sequence of the 
test procedure. Recognizing the validity of 
many of (he comments, the NHTSA instead has 
adjusted all vehicle performance values to more 
closely correlate sequential testing with normal 
everyday driving performance. This has been 
accomplished by (1) reducing the high speed 
performance requirements, (2) eliminating high 
speed performance requirements at early sequence 
test points and retaining them only in the last 
effectiveness test, (3) allowing extra burnish 
stops for reconditioning of the lining materials, 
(4) modifying fade performance requirements, 



PART 571; S 105 —PRE 14 



Efhctiv*: $«pt«mb*r I, 1975 



8. Spike stops. With regard to the spike stop 
requirements, Bendix requested that the stopping 
distance for the effectiveness (check) stops be the 
equivalent of the first effectiveness test rather 
than that of the other effectiveness tests. The 
request has merit, and the stopping distance re- 
quirements of the first effectiveness test have 
been adopted. 

GM requested that for the spike stop test 
manufacturers be allowed to use separate vehicles 
not used in the other tests, while Harvester re- 
quested a reduction in stopping speed from 60 
mph to 30 mph. Because of the changes in stop- 
ping distance that have been adopted, no further 
relief is deemed necessary and the petitions are 
denied. 

9. Parking brake systems. The parking brake 
system requirements, particularly in the lightly 
loaded vehicle condition, were objected to as 
violating the laws of physics. As mentioned 
earlier, petitioners generally requested inclusion 
of a "limit of traction" condition. Vehicles with 
a great range of loading conditions are allegedly 
incapable of holding on grades specified in the 
requirements (20 percent or 30 percent). Par- 
ticular stress was placed on brake holding capa- 
bility on a 75 skid number surface. One com- 
menter requested that the same requirements 
apply to all vehicles, claiming it unrealistic for 
light vehicles to meet the 30 percent grade re- 
quirement while heavy vehicles only had to meet 
a 20 percent requirement, and suggested use of a 
Swedish standard (16 percent grade, 110 pounds 
of foot brake force, 88 pounds of hand brake 
force). Ford requested allowance for use of a 
multistroke parking brake application. Ameri- 
can Motors Corporation requested reinstatement 
of existing Standard No. 105 requirements. GM 
and Chrysler objected to the requirement that 
the parking brake be of a "friction type" which 
they considered design restrictive, prohibiting 
other acceptable parking brake systems. 

The parking brake system test remains sub- 
stantially as adopted. The performance require- 
ments have been found feasible with present 
technology. A multistroke application is permis- 
sible, and limit of traction language has been 
added to the 30 percent grade requirement, to 
eliminate the irrelevant problem of tire slippage. 



The requirement for a friction-type parking 
brake is also retained. In a case of complete 
loss of service brake capability, a friction-type 
parking brake furnishes a residual stopping 
capability for a moving vehicle that is absent in 
a pawl-type system (such as the "park" position 
transmission stop). If the phrase "friction 
type" appears design restrictive of other types 
of parking brake systems that would provide 
equivalent capability, this agency will be recep- 
tive to suggestions for substitute language, with 
adequate supporting information. 

Wagner petitioned for deletion of the parking 
brake test with the vehicle at lightly loaded 
weight. This request is denied as the NHTSA 
believes that vehicles are frequently parked in a 
lightly loaded condition, and that a test should 
therefore be run at this vehicle weight. 

10. Indicator lamps. The standard has been 
amended so that indicator lamps may now be 
activated as a check of lamp function when the 
ignition is in the on position and the engine is 
not running, or in any position between on and 
start that is designated by the manufacturer as 
a check position. Ford petitioned that the brake 
fluid level indicator be deleted, but its request 
is denied as the NHTSA has determined that a 
warning should be provided in the event of slow 
leaks. Conversely, Mercedes-Benz of North 
America petitioned for deletion of the pressure 
differential warning, alleging that the fluid level 
indicator is sufficient. This, too, is denied, as the 
fluid level indicator will not indicate pressure 
failure until the fluid is at the level specified for 
a warning, an entirely different function. Sev- 
eral petitions asked that the 200-psi brake fluid 
pressure level be adopted (this had been proposed 
in Notice 1 for measurement at master or slave 
cylinder outlets), and these petitions have been 
granted. In response to several petitions, the 
illumination provided when an indicator lamp is 
activated may be flashing as well as steady- 
burning. 

11. Reservoirs. In the requirements for the 
master cylinder reservoir, clarifications have been 
provided in the determination of a fully worn, 
fully applied lining position. Reservoir labeling 
has been modified to require color contrasts of 
printed labels only, the contrast in lettering and 



PART 571 ; S 105 —PRE 13 



Effacliva: September 1, 1975 



background on stamped or embossed labels 
deemed a sufficient contrast in those instances. 
GM asserted that the reservoir capacity require- 
ments were unnecessary in light of the require- 
ment for a fluid level indicator, and petitioned 
that the requirements be deleted. The petition 
is denied ; the volume requirements are necessary 
to provide sufficient fluid for a full range of 
brake travel. 

12. Test conditions. The specified test load of 
50 to 725 pounds per cubic foot has been refined 
by assigning density distribution to various ve- 
hicle areas, for example 50 to 125 pounds per 
cubic foot in the seating area of all vehicles. 
Several manufacturers requested that the trans- 
mission selector control be in gear during all 
test decelerations, alleging that the neutral posi- 
tion is not representative of consumer usage. 
These requests are denied. Deceleration in gear 
by adding driveline drag masks the true effec- 
tiveness of the brake system. Comments were 
also directed to the prohibition against lockups, 
generally alleging inconsistency with Standard 
No. 121. These comments had merit, and the 
test condition has been amended to allow lockups 
during spike stops, partial failure stops and in- 
operative brake power or power assist unit stops. 
On the other hand, a request to allow more than 
one locked wheel is denied. Provision has been 
made for installation of a second thermocouple 
at the beginning of the test sequence if the lining 
wear is expected to reach a point causing the 
first thermocouple to contact the metal rubbing 
surface of a drum or rotor. Since the brake 
control forces have been modified to a uniform 
range of 15 to 150 pounds, except as otherwise 
specified, control forces have been added to the 
list of test conditions. 

13. Test procedures and sequence. Most Amer- 
ican manufacturers and suppliers commented on 
the severity of the sequential procedure, with 
arguments of the following nature: The high 
speed effectiveness tests early in the sequence 
result in changes in lining characteristics which, 
in turn, affect the capability of the vehicles to 
comply with parking brake and partial systems 
requirements. Since no reburnish is allowed 
until after the first fade test, additional lining 
deterioration occurs as light load tests and fade 



tests are run. When final effectiveness tests are 
run, organic linings (normally used in today's 
vehicles) have deteriorated appreciably. This 
sequential testing, without reconditioning at in- 
tervals, results in brake torque balance changes 
as the test sequence progresses. To offset these 
changes and to enable a vehicle to go through 
compliance tests satisfactorily, many vehicles 
would have to be designed with an initial high 
gear brake capacity. This results in an unsafe 
early rear brake lockup, particularly at the initial 
light load test. As the sequence progresses, brake 
balance shifts toward a more reasonable balance, 
where all wheels approach lockup at or near 
same point. A brake balance which is designed 
initially for GVWR test conditions to meet 
Standard 105a requirements, would be dangerous 
to consumers for normal usage at 2 to 3 passenger 
loads due to rear wheel lockup and resultant 
uncontrollable skids. Recommendations by pe- 
titioners generally favored less testing at GVWR, 
reduced maximum test speeds, lessened fade re- 
quirements, and lessened final effectiveness re- 
quirements. The various changes would allow 
design of a brake system more suitable to normal 
consumer usage rather than the usage encountered 
in 105a tests. Ford recommended some changes 
in sequence but submitted a procedure incorporat- 
ing the 105a sequence with modified performance 
requirements. GM suggested a drastically re- 
vised sequence along with reduced performance 
requirements. Several petitioners recommended 
additional burnish stops and adjustments at 
several points, generally after each effectiveness 
series. Ford proposed a 200 stop additional 
burnish after the second fade test. 

In responding to petitions for reconsideration, 
the NHTSA has not modified the sequence of the 
test procedure. Recognizing the validity of 
many of the comments, the NHTSA instead has 
adjusted all vehicle performance values to more 
closely correlate sequential testing with normal 
everyday driving performance. This has been 
accomplished by (1) reducing the high speed 
performance requirements, (2) eliminating high 
speed performance requirements at early sequence 
test points and retaining them only in the last 
effectiveness test, (3) allowing extra burnish 
stops for reconditioning of the lining materials, 
(4) modifying fade performance requirements, 



PART 671; S 105 —PRE 14 



(5) allowing a broader range of control force 
requirements while maintaining a maximum 
force limit of 150 pounds, (6) allowing extra 
adjustments of the brake system during the test 
sequence to provide more optimum brake per- 
formance, (7) modifying fade and wet-brake 
control force requirements to allow a broader 
range of forces without allowing a range that 
might produce severe over- or under- recovery. 
These modifications are intended to allow manu- 
facturers to design braking systems with a bal- 
ance that will provide satisfactory overall 
performance. 

At Ford's request, the general test procedure 
instructions have been modified to require lock- 
out of automatic adjusters prior to burnish and 
for the remainder of the test sequence. 

For the pretest instrumentation check, requests 
were received to specify a minimum number of 
instrumentation check stops or snubs, as well as 
the presently specified maximum. Such a speci- 
fication would, however, be meaningless. With 
the maximum number specified, each manufac- 



EflMHv*: Saptcmbar 1, 1975 

turer knows precisely the "worst case" that his 
vehicles must be designed for, and should test his 
vehicles at or above that level. 

In consideration of the foregoing, 49 CFR 
§ 571.105a, Motor Vehicle Safety Standard No. 
105a, is revised to read as set forth below. 

E-ffective date: September 1, 1975. Because 
these amendments relate to a standard that is 
efiFective September 1, 1975, it has been deter- 
mined for good cause shown that an efiFective 
date later than 180 days after issuance is in the 
public interest. 

(Sec. 103, 119, Pub. L. 89-563, 80 Stat. 718, 
15 use 1392, 1407; delegation of authority at 
38 F.R. 12147). 

Issued on: May 11, 1973. 

James E. Wilson 
Associate Administrator 
Traffic Safety Programs 

38 F.R. 13017 
May 18, 1973 



PART 571; S 105— PRE 15-16 



(5) allowing a broader range of control force 
requirements while maintaining a maximum 
force limit of 150 pounds, (6) allowing extra 
adjustments of the brake system during the test 
sequence to provide more optimum brake per- 
formance, (7) modifying fade and wet-brake 
control force requirements to allow a broader 
range of forces without allowing a range that 
might produce severe over- or under- recovery. 
These modifications are intended to allow manu- 
facturers to design braking systems with a bal- 
ance that will provide satisfactory overall 
performance. 

At Ford's request, the general test procedure 
instructions have been modified to require lock- 
out of automatic adjusters prior to burnish and 
for the remainder of the test sequence. 

For the pretest instrumentation check, requests 
were received to specify a minimum number of 
instrumentation check stops or snubs, as well as 
the presently specified maximum. Such a speci- 
fication would, however, be meaningless. With 
the maximum number specified, each manufac- 



EffacHv*: Sapltmbar 1, I97S 

turer knows precisely the "worst case" that his 
vehicles must be designed for, and should test his 
vehicles at or above that level. 

In consideration of the foregoing, 49 CFR 
§ 571.105a, Motor Vehicle Safety Standard No. 
105a, is revised to read as set forth below. 

Ejfective date: September 1, 1975. Because 
these amendments relate to a standard that is 
effective September 1, 1975, it has been deter- 
mined for good cause shown that an effective 
date later than 180 days after issuance is in the 
public interest. 

(Sec. 103, 119, Pub. L. 89-563, 80 Stat. 718, 
15 use 1392, 1407; delegation of authority at 
38 F.R. 12147). 

Issued on: May 11, 1973. 

James E. Wilson 
Associate Administrator 
TraflSc Safety Programs 

38 F.R. 13017 
May 18, 1973 



PART 571; S 105— PRE 15-16 



EffKliv*: S«pt«nb«r I, I97S 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 

Hydraulic Brake Systems 
(Docket No. 70-27; Notice 10) 



This notice responds to further petitions for 
reconsideration of Motor Vehicle Safety Stand- 
ard No. 105a and amends the standard in certain 
minor respects effective September 1, 1975. 

Federal Motor Vehicle Safety Standard No. 
105a, 49 CFR 571.105a, Hydraulic brake systems, 
was published on September 2, 1972 (37 F.R. 
17970). Thereafter, pursuant to 49 CFR 553.35, 
petitions for reconsideration of the rule were 
received and, in response, a revised Standard 
No. 105a was published on May 18, 1973 (38 F.R. 
13017). Timely petitions for reconsideration of 
the revised rule were received from American 
Motors Corporation (AMC), Wagner Electric 
Corporation (AVagner), General Motors Cor- 
poration (GM), International Harvester Com- 
pany (Harvester), Japan Automobile Manufac- 
turers Association (JAMA), Ford Motor 
Company (Ford), Recreational Vehicle Institute 
(RVI), and Toyota Motor Sales, USA, Inc. 
(Toyota). This notice discusses the major issues 
raised and their resolution. The Administrator 
does not consider repetitious petitions and to the 
extent that these further petitions were repeti- 
tious of the initial ones {e.g. deletion of tests 
above 80 mi/h for heavy vehicles, modification of 
pedal forces, running tests in gear rather than 
in neutral), they have not been considered, pur- 
suant to NHTSA regulations (49 CFR 553.35 
(c)). 

GM petitioned for rulemaking that would re- 
scind Standard No. 105a on the grounds that the 
brake systems it has designed for the 1976 model 
year would have to undergo substantial changes 
in subsequent model years when it plans to intro- 
duce lighter vehicles with improved fuel con- 
sumption. This agency considers energy needs 
along with other factors relevant to its rulemak- 



mg actions. 



The information available to the 
NHTSA does not indicate, however, that Stand- 
ard No. 105a is incompatible with increased fuel 
mileage, or would add substantially to the weight 
of the \ehicles covered. The NHTSA does not 
consider a ciiange in a manufacturer's own de- 
sign plans to be a justification for discarding an 
important new set of requirements for which the 
world industry has been preparing for several 
years. The petition by GM to rescind the stand- 
ard is therefore denied. 

Effectice date: Harvester and RVI petitioned 
for a delayed effective date for certain categories 
of vehicles. Harvester requested a one-year de- 
lay in the effective date for vehicles whose 
GV\VR exceeds 10,000 pounds, stating its doubt 
that acceptable antilock systems will be available 
to it by September 1, 1975, and that the advance 
hardware proposals from its brake system sup- 
pliers indicate that considerable design and de- 
velopment time is still needed. RVI wished an 
extension of 2 years for recreational vehicles 
built upon truck and multipurpose passenger 
vehicle chassis, alleging that time will be needed 
for testing and retooling after receipt of the first 
chassis or vehicle certified as conforming to the 
new braking standard. 

The NHTSA does not consider further exten- 
sion of the effective date to be in the public 
interest, and the petitions are denied. The broad 
outlines of the performance requirements have 
been known to industry since publication of the 
initial proposal in November, 1970, with its pro- 
posed effective date of September 1, 1972. Since 
publication of the new standard in September, 
1972, the effective date has been delayed one year 
to September 1, 1975. and considerable relief pro- 
vided for vehicles whose GVWR exceeds 10,000 
pounds. 



PART 571 ; S 105^PRE 17 



Effective: September 1, 1975 

Definiticms. In response to a petition by 
JAMA, a definition of "backup system" is 
adopted. Such a system is "a portion of a service 
brake system, such as a pump, that supplies 
energy in the event of a primary brake power 
source failure". 

Effective requirements. Clarifying words are 
added throughout in response to various requests. 
For example, the fourth effectiveness test now 
makes it clear that if the speed attainable in 2 
miles is 99 mi/h or greater, stops must be made 
from both 80 mi/h and a specified higher speed, 
and not from the higher speed alone. In response 
to GM"s comments on inoperative brake power 
and power assist units (S5.1.3), a new S5.1.3.4 
has been adopted that allows brake power assist 
units to be tested under the optional procedure 
if the unit utilizes a backup system. 

The word "average" has been deleted from 
S5.1.4.2 (fade and recovery) which specified fade 
stops in excess of "an average deceleration" floor, 
at the request of Wagner, as the inclusion of the 
word was erroneous and does not reflect the test 
procedures of S7.11.2.1. 

The brake system indicator lamp requirements 
(S5.3.1) were the subject of numerous petitions, 
most of which have been granted. The NHTSA 
reiterates that the methods of pressure failure 
indication in S5.3.1(a) are alternative rather 
than inclusive. Harvester asked that S5.3.1(a) 
be amended to delete the qualification of pressure 
measurement at a slave cylinder outlet "if the 
master cylinder controls slave cylinders at a 
booster unit". It argues that with this design 
configuration it should be allowed to measure 
pressure at the master cylinder outlet. The 
NHTSA agrees that the original wording of 
S5.3.1(a) is design restrictive and that measure- 
ment at either the master or slave cylinder outlet 
is satisfactory for monitoring pressure, and the 
qualifying phrase is removed. S5.3.1(a)(l) re- 
quires activation of the indicator upon activation 
of "a line pressure of not more than 200 psi". 
Ford requested an amendment to clarify that the 
intent is to specify a differential pressure between 
the operational and failed brake systems. The 
clarifying amendment has been made and the 
pressure differential increased to 225 psi to com- 
pensate for certain power-assisted units. As a 



failure indicator GM prefers a switch that would * 
activate the warning lamp when the brake pedal 
has been depressed past a certain point, rather 
than a lamp activated by fluid pressure failure. 

The petition is denied, as the NHTSA has 
determined that the brake pedal travel involved 
to activate the lamp would not provide an ade- 
quate warning. 

JAMA and Toyota asked for an amendment 
or interpretation of S5.3.2 that would allow the 
indicator lamp to remain activated when the ig- 
nition is returned to "on", after the engine is 
started. To allow the lamp to remain on after 
the engine is started might degrade the impor- 
tance of the check that the system is intended to 
indicate, and that the request is denied. JAMA 
also requested that if there is a separate parking 
brake indicator that it be labelled "Park", and 
this petition has been granted. 

GM requested that the volume requirements of 
master cylinder reservoirs on large trucks be 
reduced to one-third that required by the new 
standard. Since NHTSA has reduced the re- 
quirement in response to previous petitions, from 
150 per cent to 100 per cent of fluid displacement, ^ 
it does not deem it in the interest of safety to w 
reduce it further. GM's petition is denied. The 
agency wishes to clarify, however, that the vol- 
ume concerned is only that within the storage 
compartment, and does not include that fluid 
which may remain in pipes, hoses, and fittings. 
At Harvester's request, S5.4.2 is amended slightly 
to clarify that the minimum reservoir capacity 
is that of the total reservoir system rather than 
each reservoir compartment. 

S5.6, Brake system integrity, had been amended 
in May 1973 to specify that friction facing tear- 
out of the lining must "not exceed 10 percent of 
the lining on any frictional element" rather than 
"10 percent of the lining surface areas". GM 
requested reinstatement of the original require- 
ment. The request is denied. The language that 
was adopted in May 1973 clarified a previously 
existing ambiguity while providing a measure of 
relief that had been previously requested. 

Conditions. Ford interpreted the words "test 
load" in S6.1.1 as the load required to be added 
to bring a vehicle to its GVAVR. In some in- 
stances, if this added weight were distributed ^* 



PART 571 ; S 105— PRE 18 



Efhctlvt: S*pl*mb«r 1, 197S 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 

Hydraulic Brake Systems 
(Docket No. 70-27; Notice 10) 



This notice responds to further petitions for 
reconsideration of Motor Vehicle Safety Stand- 
ard No. 105a and amends the standard in certain 
minor respects effective September 1, 1975. 

Federal Motor Vehicle Safety Standard No. 
105a, 49 CFR 571.105a, Hydraulic brake systems, 
was published on September 2, 1972 (37 F.R. 
17970). Thereafter, pursuant to 49 CFR 553.35, 
petitions for reconsideration of the rule were 
received and, in response, a re\ised Standard 
No. 105a was published on May 18, 1973 (38 F.R. 
13017). Timely petitions for reconsideration of 
the revised rule were received from American 
Motors Corporation (AMC), AVagncr Electric 
Corporation (Wagner), General Motors Cor- 
poration (GM), International Harvester Com- 
pany (Harvester), Japan Automobile Manufac- 
turers Association (JAMA), Ford Motor 
Company (Ford), Recreational Vehicle Institute 
(RVI), and Toyota Motor Sales, USA, Inc. 
(Toyota). This notice discusses the major issues 
raised and their resolution. The Administrator 
does not consider repetitious petitions and to the 
extent that these further petitions were repeti- 
tious of the initial ones {e.g. deletion of tests 
above 80 mi/h for heavy vehicles, modification of 
pedal forces, running tests in gear rather than 
in neutral), they have not been considered, pur- 
suant to NHTSA regulations (49 CFR 553.35 
(c)). 

GM petitioned for rulemaking that would re- 
scind Standard No. 105a on the grounds that the 
brake systems it has designed for the 1976 model 
year would have to undergo substantial changes 
in subsequent model years when it plans to intro- 
duce lighter vehicles with improved fuel con- 
sumption. This agency considers energy needs 
along with other factors relevant to its rulemak- 



mg actions. 



The information available to the 
NHTSA does not indicate, however, that Stand- 
ard No. 105a is incompatible with increased fuel 
mileage, or would add substantially to the weight 
of the vehicles covered. The NHTSA does not 
consider a change in a manufacturer's own de- 
sign plans to be a justification for discarding an 
important new set of requirements for which the 
world industry has been preparing for several 
years. The petition by GM to rescind the stand- 
ard is therefore denied. 

Effective date: Harvester and RVI petitioned 
for a delayed effective date for certain categories 
of vehicles. Harvester requested a one-year de- 
lay in the effective date for vehicles whose 
GV^VR exceeds 10,000 pounds, stating its doubt 
that acceptable antilock systems will be available 
to it by September 1, 1975, and that the advance 
hardware proposals from its brake system sup- 
pliers indicate that considerable design and de- 
velopment time is still needed. RVI wished an 
extension of 2 years for recreational vehicles 
built upon truck and multipurpose passenger 
vehicle chassis, alleging that time will be needed 
for testing and retooling after receipt of the first 
chassis or vehicle certified as conforming to the 
new braking standard. 

The NHTSA does not consider further exten- 
sion of the effective date to be in the public 
interest, and the petitions are denied. The broad 
outlines of the performance requirements have 
been known to industry since publication of the 
initial proposal in November, 1970, with its pro- 
posed effective date of September 1, 1972. Since 
publication of the new standard in September, 
1972, the effective date has been delayed one year 
to September 1, 1975. and considerable relief pro- 
vided for vehicles wiiose GVWR exceeds 10,000 
pounds. 



PART 571 ; S 105— PRE 11 



Effective: September 1, 1975 



Definitloiis. In response to a petition by 
JAMA, a definition of "backup system" is 
adopted. Such a system is "a portion of a service 
brake system, such as a pump, that supplies 
energy in the event of a primary brake power 
source failure". 

Effective requirements. Clarifying words are 
added throughout in response to various requests. 
For example, the fourth eflfectiveness test now 
makes it clear that if the speed attainable in 2 
miles is 99 mi/h or greater, stops must be made 
from both 80 mi/h and a specified higher speed, 
and not from the higher speed alone. In response 
to GM's comments on inoperative brake power 
and power assist units (S5.1.3), a new S5. 1.3.4 
has been adopted that allows brake power assist 
units to be tested under the optional procedure 
if the unit utilizes a backup system. 

The word "average" has been deleted from 
S5.1.4.2 (fade and recovery) which specified fade 
stops in excess of "an average deceleration" floor, 
at the request of Wagner, as the inclusion of the 
word was erroneous and does not reflect the test 
procedures of S7.11.2.1. 

The brake system indicator lamp requirements 
(S5.3.1) were the subject of numerous petitions, 
most of which have been granted. The NHTSA 
reiterates that the methods of pressure failure 
indication in S5.3.1(a) are alternative rather 
than inclusive. Harvester asked that S5.3.1(a) 
be amended to delete the qualification of pressure 
measurement at a slave cylinder outlet "if the 
master cylinder controls slave cylinders at a 
booster unit". It argues that with this design 
configuration it should be allowed to measure 
pressure at the master cylinder outlet. The 
NHTSA agrees that the original wording of 
S5.3.1(a) is design restrictive and that measure- 
ment at either the master or slave cylinder outlet 
is satisfactory for monitoring pressure, and the 
qualifying phrase is removed. S5.3.1(a)(l) re- 
quires activation of the indicator upon activation 
of "a line pressure of not more than 200 psi". 
Ford requested an amendment to clarify that the 
intent is to specify a differential pressure between 
the operational and failed brake systems. The 
clarifying amendment has been made and the 
pressure differential increased to 225 psi to com- 
pensate for certain power-assisted units. As a 



failure indicator GM prefers a switch that would 
activate the warning lamp when the brake pedal 
has been depressed past a certain point, rather 
than a lamp activated by fluid pressure failure. 

The petition is denied, as the NHTSA has 
determined that the brake pedal travel involved 
to activate the lamp would not provide an ade- 
quate warning. 

JAMA and Toyota asked for an amendment 
or interpretation of S5.3.2 that would allow the 
indicator lamp to remain activated when the ig- 
nition is returned to "on", after the engine is 
started. To allow the lamp to remain on after 
the engine is started might degrade the impor- 
tance of the check that the system is intended to 
indicate, and that the request is denied. JAMA 
also requested that if there is a separate parking 
brake indicator that it be labelled "Park", and 
this petition has been granted. 

GM requested that the volume requirements of 
master cylinder reservoirs on large trucks be 
reduced to one-third that required by the new 
standard. Since NHTSA has reduced the re- 
quirement in response to previous petitions, from 
150 per cent to 100 per cent of fluid displacement, 
it does not deem it in the interest of safety to 
reduce it further. GM's petition is denied. The 
agency wishes to clarify, however, that the vol- 
ume concerned is only that within the storage 
compartment, and does not include that fluid 
which may remain in pipes, hoses, and fittings. 
At Harvester's request, S5.4.2 is amended slightly 
to clarify that the minimum reservoir capacity 
is that of the total reservoir system rather than 
each reservoir compartment. 

S5.6, Brake system integrity, had been amended 
in May 1973 to specify that friction facing tear- 
out of the lining must "not exceed 10 percent of 
the lining on any frictional element" rather than 
"10 percent of the lining surface areas". GM 
requested reinstatement of the original require- 
ment. The request is denied. The language that 
was adopted in May 1973 clarified a previously 
existing ambiguity while providing a measure of 
relief that had been previously requested. 

Conditions. Ford interpreted the words "test 
load" in S6.1.1 as the load required to be added 
to bring a vehicle to its GVIVR. In some in- 
stances, if this added weight were distributed 



PART 571 ; S 105— PRE 18 



E(N<Hv«: S*ptoinb«r 1, 197S 



proportionally to GAWR the front GAWR 
would be exceeded. NHTSA intended that a 
vehicle be loaded at GVIVR so that its gross 
vehicle weight is distributed proportionally to 
its GAWR, and S6.1 is amended appropriately. 
Ford, JAMA, Toyota, and RVI petitioned for a 
change in the load material density specification 
of S6.2 to allow use of iron shot or bars in the 
passenger seating area, or in cargo areas of light 
and heavy trucks. The RVI request would allow 
use of lead shot in drawers, cupboards, and cabi- 
nets of recreational vehicles. In large part, these 
requests have been granted; maximum material 
densities have been increased from 125 to 450 
pounds per cubic foot in seating areas of passen- 
ger cars, and in cargo areas of vehicles with a 
GV^VR of 10,000 pounds or less. To allow the 
use of cast iron in the cargo areas of heavy trucks 
the minimum density has been lowered slightly 
from 450 to 400 pounds per cubic foot. The RVI 
request, however, is not adopted as this would 
permit too broad a range for testing and conse- 
quent difficulty of reproducing test results. It 
was to alleviate this problem that the original 
Standard No. 105a was amended on this point 
in May 1973. AMC and GM asked that the tire 
inflation pressure be that specified for the test 
weight, rather than for the GVAVR of the ve- 
hicle. In NHTSA's view, the time to reset tire 
pressures after allowing tires to cool would com- 
plicate and lengthen test procedures. There are 
only three tests run at the lightly loaded weight, 
and no data have been submitted to show that 
the tire pressure required causes a substantial 
increase in stopping distances. 

S6.10 allows only one uncontrolled wheel to 
lock at braking speeds above 10 mph on any 
given stop. GM suggested that this section al- 
lowed one wheel per axle to lock. GM's inter- 
pretation is incorrect, however; "one wheel" 
means one wheel on the vehicle. Ford wanted 
to reset thermocouples during brake inspections. 
This requested amendment is denied. Except for 
normal adjustment, inspections for thermocouple 
depths are not allowed once a test series has be- 
gun, in order that brake systems not be disturbed. 
The NHTSA may consider different depths for 
thermocouples in the future if data are obtained 
showing a need. 



Teat procedures. GM, JAMA, Toyota, and 
RVI petitioned that lockout of automatic brake 
adjusters be optional rather than required. On 
review the NHTSA has decided that there is no 
reason not to allow use of adjusters during test- 
ing. However, if a manufacturer locks out brake 
adjusters, this will now occur when linings are 
installed after the thermocouple installation; i.e. 
before the test series rather than before burnish. 
This is intended to save time in the test proce- 
dures. 

The service brake burnish procedure for heavy 
vehicles is being amended pursuant to a petition 
by GM, to be in accord with the procedure re- 
cently proposed for such vehicles in Standard 
No. 121. Minor clarifying amendments have 
been made at various places in the test proce- 
dures. Toyota asked whether S7.9.4 applied 
only to mechanical proportioning systems. This 
paragraph applies to any variable proportioning 
system whether mechanical, electrical, hydraulic 
or otherwise. It does not apply to a fixed me- 
chanical proportioning system. 

Figures and tables. Pursuant to a request 
from Ford, the dimensional specification of "l^^ 
inches" has been added to Lever A on Figure II. 
JAMA and Toyota want to consider a modified 
T lever as a "T" rather than as an "L" type. 
The NHTSA will consider this design a "T" 
type if the short side is no less than one-third 
the long side. JAMA and Toyota requested that 
the load point on the "L" type handle be revised 
to IV2 inches from the handle end instead of 
from the center line. This request is denied, as 
the original requested dimension (30 mm) has 
been previously increased to 11/2 inches (approxi- 
mately 37 mm) and no further change is deemed 
necessary. 

Harvester was the sole petitioner to request an 
increase in the stopping distances of Table II, 
asking that vehicles with a GVWR of 10,000 
pounds or less in the lightly loaded condition be 
afforded the same maximum stopping distance 
from 60 mph as required of similarly loaded 
vehicles under the same conditions in Standard 
No. 121. It also requested an increase in the 
fourth effectiveness stopping distance to give the 
same difference in deceleration at 80 mi/h as al- 
lowed by Standard No. 105 at 60 mi/h. Both 



PART 571; S 105— PRE 19 



Effective: SapUmbar 1, 1975 



petitions are denied. Air-braked vehicles covered 
by Standard No. 121 include truck-tractors with 
a high center of gravity and usually a higher 
front-to-rear weight distribution than light 
trucks, so that the lesser stopping distance in 
Standard No. 105 is justified. The test value of 
the fourth effectiveness test reflects previous 
modifications for requirements at 60 mi/h. The 
industry in general has not disclosed any prob- 
lem in complying with the deceleration values 
from 80 mi/h. The correct stopping distance for 
heavy vehicles from 50 mi/h in the first, fourth, 
and spike effectiveness tests is 193 feet, not 183 
feet as previously published. 

GM, Toyota, and JAMA requested an increase 
in the deceleration values of Table III as an 
allowance for larger vehicles tested to optional 
brake power and assist unit procedures. This 
request is denied. The§e \ehicles are presently 
required to meet only a 6.3 ft/s/s deceleration 
which is considered the minimum value accept- 
able. 

Finally, Harvester wanted an inclusive pedal 
force range of 15 to 150 pounds for all phases of 
compliance activity including baseline checks. 
The NHTSA considers a 150-pound pedal force 
too high for baseline tests at low speeds and 



relatively low decelerations, and the petition is 
denied. 

Although the NHTSA has on occasion u.sed 
the subletter "a" to denote comprehensive revi- 
sion of existing standards effective at a future 
date, such standards will henceforth be identified 
in terms of their effective dates. Thus "Standard 
No. 105a" becomes "Standard No. 105-75 (effec- 
tive September 1, 1975)". 

In consideration of the foregoing 49 CFR 
571.105a, Motor Vehicle Safety Standard 105a, 
hydraulic brake systems, is amended as follows: 

Effective date: September 1, 1975. Because 
these amendments relate to a standard that is 
effective September 1, 1975, it has been deter- 
mined for good cause shown that an effective 
date late than 1 year after issuance is in the 
public interest. 

(Sec. 103, 119, Pub. L. 89-563, 80 Stat. 718, 
15 U.S.C. 1392, 1407; delegation of authority at 
49 CFR 1.51.) 



Issued on February 14, 1974. 



James B. Gregory 
Administrator 
39 F.R. 6708 
February 22, 1974 



PART 571 ; S 105— PRE 20 



Effcdiv*: S«pt«mb«r 1, 1975 



proportionally to GAWR the front GAWR 
would be exceeded. NHTSA intended that a 
vehicle be loaded at GVAVR so that its gross 
vehicle weight is distributed proportionally to 
its GAWR, and S6.1 is amended appropriately. 
Ford, JAMA, Toyota, and RVI petitioned for a 
change in the load material density specification 
of S6.2 to allow use of iron shot or bars in the 
passenger seating area, or in cargo areas of light 
and heavy trucks. The RVI request would allow 
use of lead shot in drawers, cupboards, and cabi- 
nets of recreational ^•ehicles. In large part, these 
requests have been granted; maximum material 
densities have been increased from 125 to 450 
pounds per cubic foot in seating areas of passen- 
ger cars, and in cargo areas of vehicles with a 
GVIVR of 10,000 pounds or less. To allow the 
use of cast iron in the cargo areas of heavy trucks 
the minimum density has been lowered slightly 
from 450 to 400 pounds per cubic foot. The RVI 
request, however, is not adopted as this would 
permit too broad a range for testing and conse- 
quent difficulty of reproducing test results. It 
was to alleviate this problem that the original 
Standard No. 105a was amended on this point 
in May 1973. AMC and GM asked that the tire 
inflation pressure be that specified for the test 
weight, rather than for the GV\VR of the ve- 
hicle. In NHTSA's view, the time to reset tire 
pressures after allowing tires to cool would com- 
plicate and lengthen test procedures. There are 
only three tests run at the lightly loaded weight, 
and no data have been submitted to show that 
the tire pressure required causes a substantial 
increase in stopping distances. 

S6.10 allows only one uncontrolled wheel to 
lock at braking speeds above 10 mph on any 
given stop. GM suggested that this section al- 
lowed one wheel per axle to lock. GM's inter- 
pretation is incorrect, however; "one wheel" 
means one wheel on the vehicle. Ford wanted 
to reset thermocouples during brake inspections. 
This requested amendment is denied. Except for 
normal adjustment, inspections for thermocouple 
depths are not allowed once a test series has be- 
gun, in order that brake systems not be disturbed. 
The NHTSA may consider different depths for 
thermocouples in the future if data are obtained 
showing a need. 



Teat procedures. GM, JAMA, Toyota, and 
RVI petitioned that lockout of automatic brake 
adjusters be optional rather than required. On 
review the NHTSA has decided that there is no 
reason not to allow use of adjusters during test- 
ing. However, if a manufacturer locks out brake 
adjusters, this will now occur when linings are 
installed after the thermocouple installation; i.e. 
before the test series rather than before burnish. 
This is intended to save time in the test proce- 
dures. 

The service brake burnish procedure for heavy 
vehicles is being amended pursuant to a petition 
by GM, to be in accord with the procedure re- 
cently proposed for such vehicles in Standard 
No. 121. Minor clarifying amendments have 
been made at various places in the test proce- 
dures. Toyota asked whether S7.9.4 applied 
only to mechanical proportioning systems. This 
paragraph applies to any variable proportioning 
system whether mechanical, electrical, hydraulic 
or otherwise. It does not apply to a fixed me- 
chanical proportioning system. 

Figures and tables. Pursuant to a request 
from Ford, the dimensional specification of "IV^ 
inches" has been added to Lever A on Figure II. 
JAMA and Toyota want to consider a modified 
T lever as a "T" rather than as an "L" type. 
The NHTSA will consider this design a "T" 
type if the short side is no less than one-third 
the long side. JAMA and Toyota requested that 
the load point on the "L" type handle be revised 
to 11/^ inches from the handle end instead of 
from the center line. This request is denied, as 
the original requested dimension (30 mm) has 
been previously increased to li^ inches (approxi- 
mately 37 mm) and no further change is deemed 
necessary. 

Harvester was the sole petitioner to request an 
increase in the stopping distances of Table II, 
asking that vehicles with a GVWR of 10,000 
pounds or less in the lightly loaded condition be 
afforded the same maximum stopping distance 
from 60 mph as required of similarly loaded 
vehicles under the same conditions in Standard 
No. 121. It also requested an increase in the 
fourth effectiveness stopping distance to give the 
same difference in deceleration at 80 mi/h as al- 
lowed by Standard No. 105 at 60 mi/h. Both 



PART 571; S 105— PRE 19 



Effective: Seplembar 1, 1975 



petitions are denied. Air-braked vehicles covered 
by Standard No. 121 include truck-tractors with 
a high center of gravity and usually a higher 
front-to-rear weight distribution than light 
trucks, so that the lesser stopping distance in 
Standard No. 105 is justified. The test value of 
the fourth effectiveness test reflects previous 
modifications for requirements at 60 mi/h. The 
industry in general has not disclosed any prob- 
lem in complying with the deceleration values 
from 80 mi/h. The correct stopping distance for 
heavy vehicles from 50 mi/h in the first, fourth, 
and spike ett'ectiveness tests is 193 feet, not 183 
feet as previously published. 

GM, Toyota, and JAMA requested an increase 
in the deceleration values of Table III as an 
allowance for larger vehicles tested to optional 
brake power and assist unit procedures. This 
request is denied. The§e vehicles are presently 
required to meet only a 6.3 ft/s/s deceleration 
which is considered the minimum value accept- 
able. 

Finally, Harvester wanted an inclusive pedal 
force range of 15 to 150 pounds for all phases of 
compliance activity including baseline checks. 
The NHTSA considers a 150-pound pedal force 
too high for baseline tests at low speeds and 



relatively low decelerations, and the petition is 
denied. 

Although the NPITSA has on occasion used 
the subletter "a" to denote comprehensive revi- 
sion of existing standards effective at a future 
date, such standards will henceforth be identified 
in terms of their effective dates. Thus "Standard 
No. lOoa" becomes "Standard No. 10.")-75 (effec- 
tive September 1, 1975)". 

In consideration of the foregoing 49 CFR 
571.105a, Motor Vehicle Safety Standard 105a, 
hydraulic brake systems, is amended as follows: 

Effective date: September 1, 1975. Because 
these amendments relate to a standard that is 
effecti/e September 1, 1975, it has been deter- 
mined for good cause shown that an effective 
date late than 1 year after issuance is in the 
public interest. 

(Sec. 103, 119, Pub. L. 89-563, 80 Stat. 718, 
15 U.S.C. 1392, 1407; delegation of authority at 
49 CFR 1.51.) 



Issued on February 14, 1974. 



James B. Gregory 
Administrator 
39 F.R. 6708 
February 22, 1974 



PART 571; S 105— PRE 20 



Effective; September 1, 1975 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 

Hydraulic Brake Systems 
(Docket No. 70-27; Notice 11) 



This notice responds to petitions for reconsid- 
eration of tlie amendments to 49 CFR .571.105- 
75, Motor Vehicle Safety Standard No. 105-75, 
published in the Federal Register on February 
22, 1974 (.39 F.R. 6708). The standard is 
amended to defer for one year the requirements 
for a brake fluid level sensor for veliicles with a 
GVWR over 10,000 pounds, and for two years, 
a 60-pound maximum baseline pedal effort on 
vehicles with a GVAVR over 15,000 pounds. 
Slightly increased stopping distances in the third 
effectiveness test are adopted for one j'ear for 
certain heavy vehicles at lightly loaded vehicle 
weight. 

Timely petitions for reconsideration of the 
amendments were received from Girling, Ltd., 
Wagner Electric Corporation (Wagner), Ford 
Motor Company (Ford), General Motors Cor- 
poration (GM), and Recreational Vehicle Insti- 
tute, Inc. (RVI). International Harvester 
Company (Harvester), subsequent to the time 
allowed for filing petitions for reconsideration, 
raised certain issues in writing to the Adminis- 
trator, and its presentation, in accordance with 
NHTSA regulations, has been considered as a 
petition for rulemaking. This notice discusses 
the major issues raised and their resolution. 

Effective date: RVI again petitioned for a 
delayed effective date for recreational vehicles 
built upon truck and multipurpose passenger 
vehicles chassis, alleging that time will be needed 
by final-stage manufacturers for testing and re- 
tooling after receipt of the first chassis or vehicle 
manufactured after the effective date of Stand- 
ard No. 105-75. 

RVI's petition is found to be repetitious of 
arguments raised ^previously, and accordingly? 
pursuant to NHTSA regulations (49 CFR 



55.3.35 (c) ), has not been granted. The denial of 
Notice 10 therefore stands, on the grounds set 
forth in Notice 10 of this docket. In brief, the 
NHTSA expects a manufacturer of incomplete 
vehicles to provide final-stage manufacturers, 
pursuant to 49 CFR 568, with information suf- 
ficient to indicate how the final-stage manufac- 
turer may achieve compliance witli Standard No. 
105-75. Since the effective date of tlie standard 
is over a j'ear away, there remains sufficient time 
for final-stage maniifacturers to discuss with 
manufacturers of incomplete vehicles the kind 
of information that is to be provided, and to 
resolve such problems as may appear. 

Harvester and Wagner have apprised the 
NHTSA of unexpected leadtime problems as.so- 
ciated with the incorporation of brake fluid in- 
dicators into master cylinders of heavy vehicles. 
The agency has confirmed the seriousness of 
these problems, and lias determined that they 
derive from factors substantially beyond the 
control of the affected vehicle manufacturers. 
It has accordingly concluded that a 1-year delay 
in the required date for introduction of fluid 
level sensors for vehicles whose GVWR exceeds 
10,000 pounds would be in the public interest. 

Harvester also requested a year's delay of the 
third effectiveness test requirements (S5.1.1.3). 
It stated that vehicles with 151 inches or less 
wheelbase and 8,000 pounds or greater GVWR 
will require anti-lock systems to meet the stop- 
ping distance requirements for lightly loaded 
vehicles, and that suitable anti-lock systems can- 
not be developed for 1976 model year production. 
The NHTSA does not consider that a year's 
delay of the third effectiveness test requirements 
is in the public interest. It finds, however, on 
the basis of the information before it that the 



PART 571 ; S 105— PRE 21 



Effective: September 1, 1975 



incorporation of anti-lock systems into this class 
of vehicles by the September 1, 1975, effective 
date is probably impracticable. The standard 
accordingly is being amended to permit, for a 
period of 1 year, somewhat longer stopping dis- 
tance requirements for lightly loaded vehicles of 
8,000 pounds or more GVWR. The NHTSA 
finds these distances to be achievable without 
anti-lock systems, and that the change for the 
interim period is justifiable in terms of the costs 
and the safety benefits involved. As an example, 
the maximum stopping distance permissible from 
60 mph at lightly loaded vehicle weight is 
changed from 216 feet to 242 feet for vehicles 
with a GVWR between 8,000 and 10,000 pounds. 

Effectiveness requirements. Clarifying words 
are again added to the effectiveness requirements 
and test procedures in response to various re- 
quests. Heretofore the performance require- 
ments for vehicles with inoperative brake power 
assist units and brake power units specified four 
stops at a deceleration figure, with the fifth and 
final stop specified in feet. This has apparently 
proved confusing, and the final stop will now 
be expressed in a manner consistent with the re- 
mainder of the performance requirements, as "an 
average deceleration of not lower than 7 fpsps". 
This value, however, applies only to passenger 
cars. Ford argued that the heavy truck stop- 
ping distance values are unrealistic, in the op- 
tional procedures provided by S5.1.3.2 and 
S5.1.3.3 for inoperative brake power assist units 
and brake power units. It petitioned for less 
stringent values. The agency has considered 
that Ford's views have merit, and is amending 
the standard to require a final stop at an average 
deceleration of not lower than 6 fpsps. Table 
III has been amended to reflect this change. 

Two petitioners contested the pedal force 
baseline value range of 15 to 60 pounds for the 
fade and recovery and water recovery demon- 
strations. GM asked that the minimum be re- 
duced to 10 pounds, while Harvester requested 
an increase in the maximum to 88 pounds. GM 
submitted new test data to substantiate its re- 
quest and its petition is granted; but a floor of 
5 pounds is placed on the recovery minimum 
value. Harvester's petition is predicated on the 
results of "extensive tests" that show "that no 
vehicle over 15,000 lbs. GVWR can be brought 



into compliance with this requirement for model 
year 1976." In recognition that even exerting 
its best efforts Harvester cannot comply by 
September 1, 1975, the NHTSA has determined 
that a relaxation of this requirement for two 
years would be in the public interest. Therefore, 
Harvester's petition is granted, and between 
September 1, 1975, and September 1, 1977, the 
maximum baseline pedal effort will be 90 pounds 
with a restriction on fade recovery of 100 pounds 
maximum, and of 110 pounds on water recovery. 

With respect to the brake failure indicator 
lamp, Ford and Wagner requested clarification 
that the pressure failure condition is a rupture 
type, rather than one resulting from slow leaks. 
This request is granted, and S5.3.1(a) is amended 
to specify that the failure causing the lamp to 
operate is "A gross loss of pressure (such as 
caused by a rupture of a brake line) . . . ." Wag- 
ner also asked whether an automatic reset pres- 
sure failure valve would violate the standard. 
When there is a slow leak in the service brake 
system, the warning valve will shuttle, activating 
the indicator lamp, but the lamp will not remain 
activated when the pedal is released and then 
reapplied. The NHTSA intends the fluid level 
indicator to warn of fluid loss due to slow leaks, 
and the pressure differential indicator to warn 
of gross pressure loss. The failure of the lamps 
to remain activated by the valve does not violate 
Standard No. 105-75. 

Some petitioners cited an apparent conflict in 
the previous denial of Toyota's petition to allow 
an indicator lamp to remain activated when the 
ignition is returned to "on" after the engine is 
started, and the fact that some systems do not 
instantly deactivate. NHTSA has previously 
noted in the notice of September 2, 1972 (37 
F.R. 17970), that no time interval is specified, 
and that instantaneous deactivation could not be 
required of continuous sensing units. The indi- 
cators considered acceptable to NHTSA are those 
that may remain activated for a limited time 
(such as 1 to 10 seconds) after the ignition is 
returned to "on". 

Finally, Wagner petitioned for reinstatement 
of the limiting phrase "in any reservoir compart- 
ment" in the requirement that an indicator lamp 
be activated whenever there is a drop in the level 
of brake fluid in a master cylinder reservoir to 



PART 571; S 105— PRE 22 



Effective: September 1, 1975 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 

Hydraulic Brake Systems 
(Docket No. 70-27; Notice 11) 



This notice responds to petitions for reconsid- 
eration of tlie amendments to 49 CFR 571.105- 
75, Motor Vehicle Safety Standard No. 105-75, 
published in the Federal Register on February 
22, 1974 (39 F.R. 6708). The standard is 
amended to defer for one year the requirements 
for a brake fluid level sensor for vehicles witli a 
GVWR over 10,000 pounds, and for two years, 
a 60-pound maximum baseline pedal effort on 
vehicles with a GVIVR over 15,000 pounds. 
Slightly increased stopping distances in the third 
effectiveness test are adopted for one year for 
certain heavy vehicles at lightly loaded vehicle 
weight. 

Timely petitions for reconsideration of the 
amendments were received from Girling, Ltd., 
Wagner Electric Corporation (Wagner), Ford 
Motor Company (Ford), General Motors Cor- 
poration (GM), and Recreational Vehicle Insti- 
tute, Inc. (RVI). International Harvester 
Company (Harvester), subsequent to the time 
allowed for filing petitions for reconsideration, 
raised certain issues in writing to the Adminis- 
trator, and its presentation, in accordance with 
NHTSA regulations, has teen considered as a 
petition for rulemaking. This notice discusses 
the major issues raised and their resolution. 

Effective date; RVI again petitioned for a 
delayed effective date for recreational vehicles 
built upon truck and multipurpose passenger 
vehicles chassis, alleging that time will be needed 
by final-stage manufacturers for testing and re- 
tooling after receipt of the first chassis or vehicle 
manufactured after the effective date of Stand- 
ard No. 105-75. 

RVI's petition is found to be repetitious of 
arguments raised ^previously, and accordingly, 
pursuant to NHTSA regulations (49 CFR 



55.3.35(c)), has not been granted. The denial of 
Notice 10 therefore stands, on the grounds set 
forth in Notice 10 of this docket. In brief, the 
NHTSA expects a manufacturer of incomplete 
vehicles to provide final-stage manufacturers, 
pursuant to 49 CFR 568, with information suf- 
ficient to indicate how the final-stage manufac- 
turer may achieve compliance witii Standard No. 
105-75. Since the effective date of the standard 
is over a year away, there remains sufficient time 
for final-stage manufacturers to discuss with 
manufacturers of incomplete veliicles the kind 
of information that is to be provided, and to 
resolve such problems as may appear. 

Harvester and Wagner have apprised the 
NHTSA of unexpected leadtime problems asso- 
ciated with the incorporation of brake fluid in- 
dicators into master cylinders of heavy vehicles. 
The agency has confirmed the seriousness of 
these problems, and has determined that they 
derive from factors substantially beyond the 
control of the affected vehicle manufacturers. 
It has accordingly conchided that a 1-year delay 
in the reqiiired date for introduction of fluid 
level sensors for vehicles whose GVWR exceeds 
10,000 pounds would be in the public interest. 

Harvester also requested a year's delay of the 
third effectiveness test requirements (S5.1.1.3). 
It stated that vehicles with 151 inches or less 
wheelbase and 8,000 pounds or greater GVWR 
will require anti-lock systems to meet tlie stop- 
l)ing distance requirements for lightly loaded 
vehicles, and that suitable anti-lock systems can- 
not be developed for 1976 model year production. 
The NHTSA does not consider that a year's 
delay of the tiiird effectiveness test requirements 
is in the public interest. It finds, however, on 
the basis of the information before it that the 



PART 571 ; S 105—PRE 21 



Effective: September I, 1975 



incorporation of anti-lock systems into this class 
of vehicles by the September 1, 1975, effective 
date is probably impracticable. The standard 
accordingly is being amended to permit, for a 
period of 1 year, somewhat longer stopping dis- 
tance requirements for lightly loaded vehicles of 
8,000 pounds or more GVWR. The NHTSA 
finds these distances to be achievable without 
anti-lock systems, and that the change for the 
interim period is justifiable in terms of the costs 
and the safety benefits involved. As an example, 
the maximum stopping distance permissible from 
60 mph at lightly loaded vehicle weight is 
changed from 216 feet to 242 feet for vehicles 
with a GVWR between 8,000 and 10,000 pounds. 

Effectiveness requirements. Clarifying words 
are again added to the effectiveness requirements 
and test procedures in response to various re- 
quests. Heretofore the performance require- 
ments for vehicles with inoperative brake power 
assist units and brake power units specified four 
stops at a deceleration figure, with the fifth and 
final stop specified in feet. This has apparently 
proved confusing, and the final stop will now 
be expressed in a manner consistent with the re- 
mainder of the performance requirements, as "an 
average deceleration of not lower than 7 fpsps". 
This value, however, applies only to passenger 
cars. Ford argued that the heavy truck stop- 
ping distance values are unrealistic, in the op- 
tional procedures provided by S5.1.3.2 and 
S5.1.3.3 for inoperative brake power assist units 
and brake power units. It petitioned for less 
stringent values. The agency has considered 
that Ford's views have merit, and is amending 
the standard to require a final stop at an average 
deceleration of not lower than 6 fpsps. Table 
III has been amended to reflect this change. 

Two petitioners contested the pedal force 
baseline value range of 1.5 to 60 pounds for the 
fade and recovery and water recovery demon- 
strations. GM asked that the minimum be re- 
duced to 10 pounds, while Harvester requested 
an increase in the maximum to 88 pounds. GM 
submitted new test data to substantiate its re- 
quest and its petition is granted; but a floor of 
5 pounds is placed on the recovery minimum 
value. Harvester's petition is predicated on the 
results of "extensive tests" that show "that no 
vehicle over 15,000 lbs. GVWR can be brouglit 



into compliance with this requirement for model 
year 1976." In recognition that even exerting 
its best efforts Harvester cannot comply by 
September 1, 1975, the NHTSA has determined 
that a relaxation of this requirement for two 
years would be in the public interest. Therefore, 
Harvester's petition is granted, and between 
September 1, 1975, and September 1, 1977, the 
maximum baseline pedal effort will be 90 pounds 
with a restriction on fade recovery of 100 pounds 
maximum, and of 110 pounds on water recovery. 

With respect to the brake failure indicator 
lamp, Ford and Wagner requested clarification 
that the pressure failure condition is a rupture 
type, rather than one resulting from slow leaks. 
This request is granted, and S5.3.1(a) is amended 
to specify that the failure causing the lamp to 
operate is "A gross loss of pressure (such as 
caused by a rupture of a brake line) . . . ." Wag- 
ner also asked whether an automatic reset pres- 
sure failure valve would violate the standard. 
When there is a slow leak in the service brake 
system, the warning valve will shuttle, activating 
the indicator lamp, but the lamp will not remain 
activated when the pedal is released and then 
reapplied. The NHTSA intends the fluid level 
indicator to warn of fluid loss due to slow leaks, 
and the pressure differential indicator to warn 
of gross pressure loss. The failure of the lamps 
to remain activated by the valve does not violate 
Standard No. 105-75. 

Some petitioners cited an apparent conflict in 
the previous denial of Toyota's petition to allow 
an indicator lamp to remain activated when the 
ignitipn is returned to "on" after the engine is 
started, and the fact that some systems do not 
instantly deactivate. NHTSA has previously 
noted in the notice of September 2, 1972 (37 
F.R. 17970), that no time interval is specified, 
and that instantaneous deactivation could not be 
required of continuous sensing units. The indi- 
cators considered acceptable to NHTSA are those 
that may remain activated for a limited time 
(such as 1 to 10 seconds) after the ignition is 
returned to "on". 

Finally, Wagner petitioned for reinstatement 
of the limiting phrase "in any reservoir compart- 
ment" in the requirement that an indicator lamp 
be activated whenever there is a drop in the level 
of brake fluid in a master cylinder reservoir to 



PART 571; S 105— PRE 22 



Effective: September ), 1975 



less than one-fourth of fluid reservoir capacity. 
The phrase was deleted in the notice of February 
22, 1974, but it should have been retained to 
clarify that a low level in any reservoir com- 
partment must be indicated. Wagner's petition 
is granted. 

Test conditions. Ford requested an amend- 
ment of the test weight condition of S6.1 to 
clarify how, in the GVAVR test condition, added 
weight is to be distributed, since even at lightly 
loaded weight on some vehicles the front axle 
load exceeds its proportional share of the GVIVR. 
The clarification is now provided by adding to 
S6.1.1 "However, if the weight on any axle at 
lightly loaded vehicle weight exceeds the axle's 
proportional share of the gross vehicle weight 
rating, the load required to reach GV^VR is 
placed so that the weight on that axle remains 
the same as at lightly loaded vehicle weight." 

Ford also asked that S6.2 Test loads be revised 
so that the manufacturer could designate the 
density of the test load selected, rather than to 
anticipate values that may be selected from 
within the prescribed range in the agency's com- 
pliance testing program. This petition is denied. 
Ford's suggestion would result in each manu- 
facturer setting its own imique performance 
requirements, and would not be appropriate for 
standards required by law to be uniform for the 
types of vehicles to which they apply. Each 
vehicle must comply with the requirements of 
the standard when loaded with materials of any 
density within the applicable ranges. This is 
made clear by the second sentence of S6., Test 
conditions: "Where a range of conditions is 
specified, the vehicle shall be capable of meeting 
the requirements at all points within the range." 

GM once again petitioned for an amendment 
of S6.4, Transmission seJectm^ control, to allow 
stopping of the test vehicle in gear rather than 
neutral. Since the agency, pursuant to 49 CFR 
§ 653.35, does not consider repetitious petitions, 
no action has been taken. 

Test procedures and sequence. S7. allows 
automatic adjusters to be locked out prior to 
burnish and for the remainder of the test se- 
quence. Girling has petitioned that lockout 



should only be in accordance with manufacturer's 
recommendations. NHTSA agrees and is amend- 
ing S7. accordingly. At the request of GM the 
agency has also amended S7. to outline a test 
procedure for conducting stops when the gear 
selector is required to be in the neutral position. 

Girling also asked that the postburnish brake 
adjustment test procedure (S7.4.1.2 and S7.4.2.2) 
be amended to make clear that these sections do 
not prohibit postburnish adjustment of man- 
ually adjustable brakes. Girling is correct, and 
appropriate amendments are made to reflect the 
agency's intent. 

Ford and Wagner both asked that the burnish 
procedure of S7.4.2.1.2 be amended in a manner 
consistent with Motor Vehicle Safety Standard 
No. 121, to allow brake applications at a point 
1.5 miles from the previous brake application for 
vehicles unable to attain any required speed in 
1 mile. The petition is granted, and tlie standard 
is amended accordingly. 

Finally, Ford suggested that the test proce- 
dure for first reburnish, S7.6, be changed to re- 
flect the optional procedure of S7.4.2.1.2, and 
this request has also been granted. 

Other minor amendments have been made to 
correct printing errors and for internal consist- 
ency. 

In consideration of the foregoing, 49 CFR 
571.105-75, Motor Vehicle Safety Standard No. 
105-75, is amended .... 

Effective date: September 1, 1975. Because 
these amendments relate to a standard that is 
effective September 1, 1975, it has been deter- 
mined for good cause shown that an effective 
date later than 1 year after issuance is in the 
public interest. 

(Sees. 103, 119, Pub. L. 89-563, 80 Stat. 718, 
15 U.S.C. 1392, 1407; delegation of authority at 
49 CFR 1.51.) 



Issued on July 9, 1974. 



James B. Gregory 
Administrator 

39 F.R. 25943 
July 15, 1974 



PART 571; S 105— PRE 23-24 



Effective: September 1, 1975 



less than one- fourth of fluid reservoir capacity. 
The phrase was deleted in the notice of February 
22, 1974, but it should have been retained to 
clarify that a low level in any reservoir com- 
partment must be indicated. Wagner's petition 
is granted. 

Test coTiditions. Ford requested an amend- 
ment of the test weight condition of S6.1 to 
clarify how, in the GVWR test condition, added 
weight is to be distributed, since even at lightly 
loaded weight on some vehicles the front axle 
load exceeds its pi-oportional share of the GVAVR. 
The clarification is now provided by adding to 
S6.1.1 "However, if the weight on any axle at 
lightly loaded vehicle weight exceeds the axle's 
proportional share of the gross vehicle weight 
rating, the load required to reach G\nVR is 
placed so that the weight on that axle remains 
the same as at lightly loaded vehicle weight." 

Ford also asked that S6.2 Tesf loads be revised 
so that the manufacturer could designate the 
density of the test load selected, rather than to 
anticipate values that may be selected from 
within the prescribed range in the agency's com- 
pliance testing program. This petition is denied. 
Ford's suggestion would result in each manu- 
facturer setting its own unique performance 
requirements, and would not be appropriate for 
standards requii'ed by law to be uniform for the 
types of vehicles to which they apply. Each 
vehicle must comply with the requirements of 
the standard when loaded with materials of any 
density within the applicable ranges. This is 
made clear by the second sentence of S6., Test 
conditions: "Where a range of conditions is 
specified, the vehicle shall be capable of meeting 
the requirements at all points within the range." 

GM once again petitioned for an amendment 
of S6.4, Transmission selector control, to allow 
stopping of the test vehicle in gear rather than 
neutral. Since the agency, pursuant to 49 CFR 
§ 553.35, does not consider repetitious petitions, 
no action has been taken. 

Test procedures and sequence. S7. allows 
automatic adjusters to be locked out prior to 
burnish and for the remainder of the test se- 
quence. Girling has petitioned that lockout 



should only be in accordance with manufacturer's 
recommendations. NHTSA agrees and is amend- 
ing S7. accordingly. At the request of GM the 
agency has also amended S7. to outline a test 
procedure for conducting stops when the gear 
selector is required to be in the neutral position. 

Girling also asked tliat the postburnish brake 
adjustment test procedure (S7.4.1.2 and S7.4.2.2) 
be amended to make clear that these sections do 
not prohibit postburnish adjustment of man- 
ually adjustable brakes. Girling is correct, and 
appropriate amendments are made to reflect the 
agency's intent. 

Ford and Wagner both asked tliat the burnish 
procedure of S7.4.2.1.2 be amended in a manner 
consistent with Motor Vehicle Safety Standard 
No. 121, to allow brake applications at a point 
1.5 miles from the previous brake application for 
vehicles unable to attain any required speed in 
1 mile. The petition is granted, and the standard 
is amended accordingly. 

Finally, Ford suggested that the test proce- 
dure for first reburnish, S7.6, be changed to re- 
flect the optional procedure of S7.4.2.1.2, and 
this request has also been granted. 

Other minor amendments have been made to 
correct printing errors and for internal consist- 
ency. 

In consideration of the foregoing, 49 CFR 
571.105-75, Motor Vehicle Safety Standard No. 
105-75, is amended .... 

Effective date: September 1, 1975. Because 
these amendments relate to a standard that is 
eff'ective September 1, 1975, it has been deter- 
mined for good cause shown that an effective 
date later than 1 year after issuance is in the 
public interest. 

(Sees. 103, 119, Pub. L. 89-563, 80 Stat. 718, 
15 U.S.C. 1392, 1407 ; delegation of authority at 
49 CFR 1.51.) 



Issued on July 9, 1974. 



James B. Gregory 
Administrator 

39 F.R. 25943 
July 15, 1974 



Wj 



PART 571; S 105— PRE 23-24 



i 



I 



Effective: September 1, 197S 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 

Hydraulic Brake Systems 
(Docket No. 70-27; Notice 13) 



This notice amends Standard No. 105-75, Hy- 
draulic brake systems, 40 CFR 571.105-75, as it 
applies to passenger cars, in response to peti- 
tions for reconsideration of amendments pub- 
lished July 15, 1974 (39 F.R. 25943) (Notice 11). 
The amendments defer for one year the require- 
ment for a brake fluid level indicator and modify 
the permissible pedal force values used in re- 
covery stops. 

Manufacturers of hydraulic-braked motor ve- 
hicles responded to the Notice 11 amendments 
of the standard with petitions for reconsideration 
of specific technical changes in some performance 
requirements, and also with far-ranging requests 
for substantial modification, delay, or revocation 
of the standard. These broad requests are an- 
swered in a separate proposal to delay the effec- 
tive date of the standard for four months in the 
case of passenger cars, and indefinitely in the case 
of multipurpose passenger vehicles (MPV's), 
trucks, and buses. For this reason, only the spe- 
cific technical elements that necessarily affect 
passenger cars are addressed in this notice. 

Brake ftuid level indicator. Chrysler Corpora- 
tion, Ford Motor Company, General Motors, and 
Wagner Electric Corporation responded to the 
1-year delay in fluid level indicator requirements 
for heavy vehicles by asserting that procurement 
and reliability problems also exist for lighter 
vehicle categories. The NHTSA contacted several 
manufacturers of brake fluid level indicators and 
discussed the availability and reliability of their 
products. It appeared that further field evalua- 
tion of available indicators could improve their 
reliability and that some delay should solve the 
availability problems which existed. At the Feb- 
ruary 11 public meeting, American Motors Cor- 
poration confirmed that availability problems 



still exist for brake fluid level indicators. Con- 
sequently, the NHTSA amends the standard to 
defer requirements for brake fluid level indicators 
until September 1, 1976. 

International Harvester requested clarification 
in the wording of S5.3.1(b), which appears to 
require a signal if the amount of brake fluid in 
a small, nearly full compartment of a split sys- 
tem reservoir does not equal one-quarter of the 
volume of the larger compartment. The NHTSA 
agrees that confusion may arise from the present 
wording, and, without changing the intended 
meaning of the requirement in any way, amends 
the wording as requested by Harvester. 

Ford requested a clarification of wording in 
S5.3.1(a), which presently calls for a signal when 
"any" one of several pressure losses is experienced. 
Ford correctly notes that the NHTSA use of 
"any" means that the vehicle or system must be 
capable of meeting the specified requirement upon 
the occurrence of every condition listed, and that, 
in this case, such was not intended. The NHTSA 
has corrected the wording to make clear that 
only one of the conditions (at the option of the 
manufacturer) must be indicated by the brake 
system indicator lamp. 

Maximnm and minimum brake pedal force — 
recovery stops. Chrysler and the Japan Auto- 
mobile Manufacturers Association (JAMA) sup- 
ported the Notice 11 reduction of baseline pedal 
force limits to permit optimization of braking 
characteristics over the whole range of system 
operating conditions. Their petitions argued for 
an additional change to the minimum pedal 
effort in the first through fourth recovery stops 
to encourage optimal recovery characteristics. 
Specifically, Chrysler recommended that the 
present 15-pound limit (S6.1.13) on minimum 



»; 



PART 571 ; S 105— PRE 25 



Iffxtive: September 1, 1975 



pedal force in the early recovery stops be re- 
placed by a forinida tied to the average control 
force for the baseline check. To avoid over- 
sensitive brakes, a minimum pedal force of five 
pounds would be required. 

The NHTSA concludes that such a requirement 
would allow greater design freedom in optimizing 
brake recovery without sacrificing limits on brake 
sensitivity. Accordingly, the NHTSA reconsiders 
its action on minimum brake control force re- 
quirements, and amends the standard in response 
to JAMA and Chrysler. 

Chrysler also raised the issue of maximum al- 
lowable pedal force in the fifth stop of the water 
recovery requirements. Presently this pedal force 
can be a maximum of 90 pounds (60 pounds for 
average control force in the baseline check plus 
30 pounds), but this formula requires lower pedal 
force on a \ehicle with lower average baseline 
pedal force. Chrysler has considered changes in 
brake lining to lower the wet recovery stop values, 
but the modifications include major disadvantages 
such as increased brake imbalance, larger boosters, 
noise, and wear. The NHTSA finds that the 
formula can be revised to avoid penalizing good 
baseline performance, while maintaining a 90- 
pound maximum effort. Accordingly, S5. 1.2.5 
is amended to permit a 45-pound increase of pedal 
effort, as long as the maximum effort does not 
exceed 90 pounds. 

Other requirements of the standard. Wagner 
requested that the Notice 11 revisions of "in 
neutral" procedures be made consistent with other 
provisions of the standard, or that they be re- 
placed with other procedures. The NHTSA finds 
the present procedure more reproducible than 
that suggested by Wagner and therefore denies 
this petition. Wagner correctly pointed out that 
the procedure to "exceed the test speed by approx- 
imately seven mph" may contradict the require- 
ment of testing at speeds only four mph lower 
than maximum attainable speeds (S5.1). Ac- 
cordingly, "four to eight mph" is substituted for 
"approximately seven mph" in S7. 



In a related area, JAMA requested that the 
test procedure for wet brake reco\-ery stops be 
modified (S7.16.2). The NHTSA did not ad- 
dress these procedures in Notice 11, and does 
not find that this new subject matter is appro- 
priate for consideration at this time. The JAMA 
petition will be considered as a petition for rule- 
making which will be addressed in the near 
future. 

Bendix requested clarification of the Notice 8 
preamble discussion of "power assist" and 
"power" units. Bendix's question arose with re- 
gard to its "hydro-boost" unit, which is described 
as designed with a "push through" capability in 
both the "normal" and "failed power" operating 
conditions, and with an acounulator that permits 
low pedal effort for a limited number of brake 
applications after a power failure has occurred. 
The NHTSA concludes that, because the Benaix 
"hydro-boost" does not prevent the operator from 
braking the \ehicle by an application of muscular 
force in the "failed power" condition, it qualifies 
as a brake power assist unit under the definitions 
of Standard No. 105-75. 

Several minor amendments have been made to 
correct a printing error in Table I as it appeared 
in Notice 8 (38 F.E. 13017. ISIay 18, 1973) and 
for consistency in the use of abbreviations and 
terminology. 

In consideration of the foregoing. Standard 
No. 105-75 (49 CFR 571.105-75) is amended 

Effective date: September 1. 1975: Because the 
amendments relax a requirement and because the 
present effective date of the standard is Septem- 
ber 1, 1975, it is found for good cause shown 
that an effective date sooner than 180 days fol- 
lowing publication of the amendments in the 
Federal Register is in the public interest. 

(Sec. 103, 119, Pub. L. 89-563, 80 Stat. 718 
(15 U.S.C. 1392, 1407); delegation of authority 
at 49 CFR 1.51) 

Issued on March 6, 1975. 

Noel C. Bufe 
Acting Administrator 

40 F.R. 11584 
March 12, 1975 



PART 571 ; S 105— PRE 26 



Effective: September 1, 1975 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 

Hydraulic Brake Systems 
(Docket No. 70-27; Notice 13) 



This notice amends Standard No. 105-75, Hy- 
draulic brake systems, 40 CFR 571.105-75, as it 
applies to passenger cars, in response to peti- 
tions for reconsideration of amendments pub- 
lished July 15, 1974 (39 F.R. 25943) (Notice 11). 
The amendments defer for one year the require- 
ment for a brake fluid level indicator and modify 
the permissible pedal force values used in re- 
covery stops. 

Manufacturers of hydraulic-braked motor ve- 
hicles responded to the Notice 11 amendments 
of the standard with petitions for reconsideration 
of specific technical changes in some performance 
requirements, and also with far-ranging requests 
for substantial modification, delay, or revocation 
of the standard. These broad requests are an- 
swered in a separate proposal to delay the effec- 
tive date of the standard for four months in the 
case of passenger cars, and indefinitely in the case 
of multipurpose passenger vehicles (MPV's), 
trucks, and buses. For this reason, only the spe- 
cific technical elements that necessarily affect 
passenger cars are addressed in this notice. 

Brake fluid level indicator. Chrysler Corpora- 
tion, Ford Motor Company, General Motors, and 
Wagner Electric Corporation responded to the 
1-year delay in fluid level indicator requirements 
for heavy vehicles by asserting that procurement 
and reliability problems also exist for lighter 
vehicle categories. The NHTSA contacted several 
manufacturers of brake fluid level indicators and 
discussed the availability and reliability of their 
products. It appeared that further field evalua- 
tion of available indicators could improve their 
reliability and that some delay should solve the 
availability problems which existed. At the Feb- 
ruary 11 public meeting, American Motors Cor- 
poration confirmed that availability problems 



still exist for brake fluid level indicators. Con- 
sequently, the NHTSA amends the standard to 
defer requirements for brake fluid level indicators 
until September 1, 1976. 

International Harvester requested clarification 
in the wording of S5.3.1(b), which appears to 
require a signal if the amount of brake fluid in 
a small, nearly full compartment of a split sys- 
tem reservoir does not equal one-quarter of the 
volume of the larger compartment. The NHTSA 
agrees that confusion may arise from the present 
wording, and, without changing the intended 
meaning of the requirement in any way, amends 
the wording as requested by Harvester. 

Ford requested a clarification of wording in 
S5.3.1(a), which presently calls for a signal when 
"any" one of several pressure losses is experienced. 
Ford correctly notes that the NHTSA use of 
"any" means that the vehicle or system must be 
capable of meeting the specified requirement upon 
the occurrence of every condition listed, and that, 
in this case, such was not intended. The NHTSA 
has corrected the wording to make clear that 
only one of the conditions (at the option of the 
manufacturer) must be indicated by the brake 
system indicator lamp. 

Maximum and minimum brake pedal force — 
recovery stops. Chrysler and the Japan Auto- 
mobile Manufacturers Association (JAMA) sup- 
ported the Notice 11 reduction of baseline pedal 
force limits to permit optimization of braking 
characteristics o\er the whole range of system 
operating conditions. Their petitions argued for 
an additional change to the minimum pedal 
effort in the first through fourth recovery stops 
to encourage optimal recovery characteristics. 
Specifically, Chrysler recommended that the 
present 15-pound limit (S6.1.13) on minimum 



PART 571 ; S 105— PRE 25 



Effacllvc S«plemb«r 1, 1975 



pedal force in the early recovery stops be re- 
placed by a formula tied to the average control 
force for the baseline check. To avoid over- 
sensitive brakes, a minimum pedal force of five 
pounds would be required. 

The NHTSA concludes that such a requirement 
would allow greater design freedom in optimizing 
brake recovery without sacrificing limits on brake 
sensitivity. Accordingly, the NHTSA reconsiders 
its .action on minimum brake control force re- 
quirements, and amends the standard in response 
to JAMA and Chrysler. 

Chrysler also raised the issue of maximum al- 
lowable pedal force in the fifth stop of the water 
recovery requirements. Presently this pedal force 
can be a maximum of 90 pounds (60 pounds for 
average control force in the baseline check plus 
30 pounds), but this formula requires lower pedal 
force on a vehicle with lower average baseline 
pedal force. Chrysler has considered changes in 
brake lining to lower the wet recovery stop values, 
but the modifications include major disadvantages 
such as increased brake imbalance, larger boosters, 
noise, and wear. The NHTSA finds that the 
formula can be revised to avoid penalizing good 
baseline performance, while maintaining a 90- 
pound maximum effort. Accordingly, S5. 1.2.5 
is amended to permit a 45-pound increase of pedal 
effort, as long as the maximum effort does not 
exceed 90 pounds. 

Other requirements of the standard. Wagner 
requested that the Notice 11 revisions of "in 
neutral" procedures be made consistent with other 
provisions of the standard, or that they be re- 
placed with other procedures. The NHTSA finds 
the present procedure more reproducible than 
that suggested by AVagner and therefore denies 
this petition. Wagner correctly pointed out that 
the procedure to "exceed the test speed by approx- 
imately seven mph" may contradict the require- 
ment of testing at speeds only four mph lower 
than maximum attainable speeds (S5.1). Ac- 
cordingly, "four to eight mph" is substituted for 
"approximately seven mph" in S7. 



In a related area, JAMA requested that the 
test procedure for wet brake recovery stops be 
modified (S7.16.2). The NHTSA did not ad- 
dress these procedures in Notice 11, and does 
not find that this new subject matter is appro- 
priate for consideration at this time. The JAMA 
petition will be considered as a petition for rule- 
making which will be addressed in the near 
future. 

Bendix requested clarification of the Notice 8 
preamble discussion of "power assist" and 
"power" units. Bendix's question arose with re- 
gard to its "hydi'o-boost" unit, which is described 
as designed with a "push through" capability in 
both the "normal" and "failed power" operating 
conditions, and with an accumulator that permits 
low pedal effort for a limited number of brake 
applications after a power failure has occurred. 
The NHTSA concludes that, because the Bendix 
"hydro-boost" does not prevent the operator from 
braking the \ehicle by an application of muscular 
force in the "failed power" condition, it qualifies 
as a brake power assist unit >mder the definitions 
of Standard No. 105-75. 

Several minor amendments have been made to 
correct a printing error in Table I as it appeared 
in Notice 8 (38 F.R. 13017. May 18, 1973) and 
for consistency in the use of abbreviations and 
terminology. 

In consideration of the foregoing. Standard 
No. 105-75 (49 CFR 571.105-75) is amended 

Effective date: September 1. 1975: Because the 
amendments relax a i-equirenient and because the 
present effective date of the standard is Septem- 
ber 1,. 1975, it is foimd for good cause shown 
that an effective date sooner than 180 days fol- 
lowing publication of the amendments in the 
Federal Register is in the public interest. 

(Sec. 103, 119. Pub. L. 89-563, 80 Stat. 718 
(15 U.S.C. 1392, 1407); delegation of authority 
at 49 CFR 1.51) 

Issued on March 6, 1975. 

Noel C. Bufe 
Acting Administrator 

40 F.R. 11584 
March 12, 1975 



PART 571 ; S 105— PRE 26 



Effective: September 1, 1975 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 



Hydraulic Brake Systems 
(Docket No. 70-27; Notice 14) 



This notice amends Standard No. 105-75, Hy- 
dranlic hrake systems, 49 CFR 571.105-75, to 
make it applicable only to passenger cars equipped 
with hydraulic brake systems. This amendment 
has the effect of withdrawing the standard's ap- 
plicability to multipurpose passenger vehicles 
(MPV's), trucks, and buses equipped with hy- 
draulic brake systems. 

The National Highway Traffic Safety Admin- 
istration (NHTSA) proposed a 4-month delay of 
the standard as it applies to passenger cars and 
indefinite delay as it applies to other hydraulic- 
braked vehicles (40 FR 10483, March 6, 1975). 
Manufacturers responded to the proposed 4-month 
delay for passenger cars with objections to tech- 
nical features of the standard, the costs of mid- 
year changes, and the NHTSA's estimate of the 
standard's safety benefits. While consideration 
of these issues continues, a decision has been 
made to withdraw the standard's applicability to 
trucks, buses, and MPV's. 

The NHTSA proposed withdrawal of the 
standard because of uncertainty that the particu- 
lar performance levels established for trucks. 
MPV's, and buses by Standard No. 105-75 were 
justified in view of their costs. It is clear that 
tnick braking is in many cases substantially 
poorer than passenger car braking, and that the 
generally longer stopping distances and the 
greater severity of truck accidents justify a safety 
standard for these vehicles. At the same time, 
the costs of meeting Standard No. 105-75 in all 
truck, bus, and MPV model lines are substantial 
and the NHTSA is not prepared to conclude that 
they are justified in view of achievable safety 
benefits. 



The Center for Auto Safety (CFAS) ques- 
tioned the NHTSA's right to propose withdrawal 
of a promulgated rule in response to manufac- 
turer cost objections without publication of the 
agency's evaluation of the submitted cost data. 
As authority, CFAS cites the newly-enacted cost 
information provisions of the National Traffic 
and Motor Vehicle Safety Act (15 U.S.C. § 1402). 

In this case manufacturers submitted costs for 
light- to medium-duty trucks that ranged from 
$54 to $775 per unit (depending on model con- 
figuration) to attain compliance with the stand- 
ard. The NHTSA compared these figures with 
independently-gathered detailed cost and mark- 
up information and substantiated that the manu- 
facturer's estimates were accurate. This material 
has been formally compiled as required by the 
Act and has been made public in the docket (70- 
27; Notice 12). 

CFAS, the Consumers Union. Ms. Susan P. 
Baker of Johns Hopkins University, the Insur- 
ance Institute for Highway Safety, and the 
Permanente Medical Group stressed the import- 
ance of a brake standard for these vehicles. 
Tlie NHTSA agrees and intends to issue interim 
requirements for MPV's, trucks, and buses 
equipped with hydraulic brake systems. How- 
ever, the NHTSA concludes that the Standard 
105-75 requirements in their present form cannot 
be justified for trucks, buses, and MPV's on the 
basis of the data available at this time. 

In consideration of the foregoing. Standard 
No. 105-75 (49 CFR 571.105-75) is amended 

Effective date: September 1, 1975. Because 
the effective date of the standard for trucks, 
buses, and MPV's was less than 180 days after 
the date of publication of this amendment in the 



PART 571 ; S 105— PRE 27 



Effective: September 1, 1975 

Federal Register, it is found for good cause Issued on April 25, 1975. 

shown that an effective date less than 180 days 

from the date of publication is in the public ^ -r. ^ 

interest. J^"^^.^ ^- Gregory 

(Sec. 103, 119, Pub. L. 89-563, 80 Stat. 718 (15 Administrator 

U.S.C. 1392, 1407); delegation of authority at 40 F.R. 18411 

49 CFR 1.51). April 28, 1975 



i 



I 



PART 571 ; S 105— PRE 28 



Effective: September 1, 1975 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 



Hydraulic Brake Systems 
(Dockef No. 70-27; Notice 14) 



This notice amends Standard No. 105-75, Hy- 
draulic brake systems, 49 CFR 571.105-75, to 
make it applicable only to passenger cars equipped 
with hydraulic brake systems. This amendment 
has the effect of withdrawing the standard's ap- 
plicability to multipiirpose passenger vehicles 
(MPV's), trucks, and buses equipped with hy- 
draulic brake systems. 

The National Highway Traffic Safety Admin- 
istration (NHTSA) proposed a 4-month delay of 
the standard as it applies to passenger cars and 
indefinite delay as it applies to other hydraulic- 
braked vehicles (40 FR 10483, March 6, 1975). 
Manufacturers responded to the proposed 4-month 
delay for passenger cars with objections to tech- 
nical features of the standard, the costs of mid- 
year changes, and. the NHTSA's estimate of the 
standard's safety benefits. AVhile consideration 
of these issues continues, a decision has been 
made to withdraw the standard's applicability to 
trucks, buses, and MPV's. 

The NHTSA proposed withdrawal of the 
standard because of uncertainty that the particu- 
lar performance levels established for trucks. 
MPV's, and buses by Standard No. 105-75 were 
justified in view of their costs. It is clear that 
tnick braking is in many cases substantially 
poorer than passenger car braking, and that the 
generally longer stopping distances and the 
greater severity of truck accidents justify a safety 
standard for these vehicles. At the same time, 
the costs of meeting Standard No. 105-75 in all 
truck, bus, and MPV model lines are substantial 
and the NHTSA is not prepared to conclude that 
they are justified in view of achievable safety 
benefits. 



The Center for Auto Safety (CFAS) ques- 
tioned the NHTSA's right to propose withdrawal 
of a promulgated rule in response to manufac- 
t>irer cost objections without publication of the 
agency's evaluation of the submitted cost data. 
As authority, CFAS cites the newly-enacted cost 
information provisions of the National Traffic 
and Motor Vehicle Safety Act (15 U.S.C. § 1402). 

In this case manufacturers submitted costs for 
light- to medium-duty trucks that ranged from 
$54 to $775 per unit (depending on model con- 
figuration) to attain compliance with the stand- 
ard. The NHTSA compared these figures with 
independently-gathered detailed cost and mark- 
up information and substantiated that the manu- 
facturer's estimates were accurate. This material 
has been formally compiled as required by the 
Act and has been made public in the docket (70- 
27; Notice 12). 

CFAS, the Consumers Union. Ms. Susan P. 
Baker of Johns Hopkins University, the Insur- 
ance Institute for Highway Safety, and the 
Permanente Jledical Group stressed the import- 
ance of a brake standard for these vehicles. 
Tlie NHTSA agrees and intends to issue interim 
requirements for MPV's, trucks, and buses 
equipped with hydraulic brake systems. How- 
ever, the NHTSA concludes that the Standard 
105-75 requirements in their present form cannot 
be justified for trucks, buses, and MPV's on the 
basis of the data available at this time. 

In consideration of the foregoing. Standard 
No. 105-75 (49 CFR 571.105-75) is amended 

Effective date: September 1, 1975. Because 
the effective date of the standard for trucks, 
buses, and MPV's was less than 180 days after 
the date of publication of this amendment in the 



PART 571 ; S 105— PRE 27 



Effective: September 1, 1975 

Federal Register^ it is found for good cause Issued on April 25, 1975. 

shown tiiat an ett'ective date less than 180 days 

from the date of publication is in the public t t^ /~c 

■ . . James B. (jreeory 

interest. aj ■ • f 

(Sec. 103, 119, Pub. L. 89-563, 80 Stat. 718 (15 Admmistrator 

IT.S.C. 1392, 1407); delegation of authority at 40 F.R. 18411 

49 CFR 1.51). April 28, 1975 



I 



PART 571 ; S 105— PRE 28 



Effective: June 9, 1975 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 

Hydraulic Brake Systems 

(Docket No. 70-27; Notice 15) 



This notice amends Standard No. 105-75, Hy- 
draulic hrake .systems, 49 CFR 571.105-75, to de- 
lay its effective date four montlis from September 
1, 1975, to January 1, 1976, and to establish in- 
terim control force values for water recovery 
testing. This notice also amends the present hy- 
draulic brake system standard for passenger cars 
(Standard No. 105, Hydraulic hrake systems, (49 
CFR 571.105)) to permit compliance with that 
standard or the new standard at the option of 
the manufacturer until January 1, 1976. 

As issued, Standard No. 105-75 applied to 
passenger cars, trucks, buses, and multipurpose 
passenger vehicles (MPV's) equipped with hy- 
draulic brake systems. Its scheduled effective 
date was September 1, 1975. Thirteen petitions 
for rulemaking to postpone or revoke the stand- 
ard were filed with the NHTSA earlier this year. 
Following a comprehensive evaluation of the 
petitions, the NHTSA proposed and made final 
an indefinite delay of the standard as it applied 
to trucks, buses, and MPV's (40 F.R. 10483, 
March 6, 1975; 40 F.R. 18411, April 28, 1975). 

At the same time, the agency denied petitions 
for substantial postponement or revocation of the 
standard as it applies to passenger cars, having 
considered the cost of compliance for those ve- 
hicles, and having determined that significant 
safety benefit will derive from better stopping 
performance, stability, and pedal force levels (40 
F.R. 10483, ISIarch 6. 1975). A discussion of the 
potential benefits accompanied that decision. An 
economic evaluation of the impact of the standard 
will be available in the public docket. The only 
revisions of the standard proposed by the NHTSA 
were an interim pedal force value and a 4-month 
delay of effective date, to permit some flexibility 
in new model introduction dates where technical 



changes or isolated compliance problems had not 
l)een resolved. 

Manufacturer comments on the proposal were 
generally unresponsive to the proposed delay of 
four months and the interim pedal force value of 
110 pounds in wet reco\ery stops. The Vehicle 
Equipment Safety Commission considered the 
proposed pedal force values to be overgenerous. 
Chrysler Corporation indicated its support for 
the 4-month delay and interim value but em- 
phasized other arguments in its submission. Gren- 
eral Motors requested that the pedal force value 
be made permanent. It appears that manufac- 
turers support the short delay and pedal force 
modification to simplify introduction of the 1976 
models. Accordingly, the standard is modified 
as proposed, to establish an amended effective 
date of January 1, 1976, and a pedal force in- 
crease of 60 pounds up to a total of 110 pounds 
(in S5.1.5.2) until September 1, 1976. 

The majority of comments restated manufac- 
turer positions on the issue of substantial delay 
or revocation of the standard for passenger cars. 
Tlie NHTSA has already considered this issue 
and, as noted above, concluded that the benefits 
of improved stopping performance, stability, and 
pedal force \alues outweigh the costs of imple- 
mentation. Manufacturers submitted no new data 
that would justify a reversal of NHTSA's earlier 
decision. 

Although the NHTSA limited its proposal to 
!i choice between tlie effective dates of September 
1. 1975, and January 1, 1976, several manufac- 
turers compared the cost savings of a short delay 
to January 1, 1976, with a substantially longer 
delay to September 1, 1976. Actually, the Jan- 
uary 1 date was proposed in order to ease the 
introduction of new models after September 1, 



PART 571 ; S 10»— PRE 29 



EfFeclive: June 9, 1975 



1975, and was not proposed as a means of re- 
ducing costs. The proposal was largely in re- 
sponse to manufacturers' comments that some 
1976 models would be introduced substantially 
later than normal so that 1975 model production 
might be extended beyond September 1, 1975. 
The NHTSA believes that the three years of lead- 
time since promulgation of Standard No. 105-75 
have been sufficient to permit tlie design and test- 
ing of complying brake systems in nearly all 
cases. With tlie 4-month transitional period, a 
manufacturer will be free to introduce the new 
brake systems along with its new model introduc- 
tion, as dictated by the economic situation of the 
automotive industry. 

Ford and Chrysler suggested that the standard 
could be improved by reduced loading during 
brake fade testing. These companies argue that 
present-day brake balance must be modified to 
meet the brake- fade and fourth effectiveness test 
of Standard No. 105-75 and that the new balance 
is not optimum. Agency testing demonstrates 
that many present-day vehicles can in fact meet 
the requirements as their brakes are balanced 
and suggests that major departures from current 
brake balance design will generally not be re- 



quired to comply with fade requirements under 
the present test conditions. The NHTSA accord- 
ingly concludes that the presently-specified load- 
ing does not result in characteristics which would 
justify delay of the standard and the consequent 
loss of benefits during the period of delay. 

In consideration of the foregoing, Standard 
No. 105-75 (49 CFR 571.105-75) is amended 

Effective date: The date on which Standard 
No. 105-75 becomes mandatory for all passenger 
cars is January 1, 1976. However, the effective 
date of the amendments to both Standard No. 
105-75 and Standard No. 105 is June 9, 1975, and 
passenger cars manufactured between that date 
and January 1, 1976, may conform to either 
standard at the discretion of the manufacturer. 

(Sec. 103, 119, Pub. L. 89-563, 80 Stat. 718 (15 
U.S.C. 1392, 1407) ; delegation of authority at 
49 CFR 1.51.) 

Issued on June 5, 1975. 

James B. Gregory 
Administrator 

40 F.R. 24525 
June 9, 1975 



PART 571 ; S 105— PRE 30 



EfFectlve: June 9, 197S 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 

Hydraulic Brake Systems 
(Docket No. 70-27; Notice 15) 



This notice amends Standard No. 105-75, Hy- 
draulic brake fiystems, 49 CFR 571.105-75, to de- 
lay its effective date four months from September 
1, 1975, to January 1, 1976, and to establish in- 
terim control force values for water recovery 
testing. This notice also amends the present hy- 
draulic brake system standard for passenger cars 
(Standard No. 105, Hydraulic brake systems, (49 
CFR 571.105)) to permit compliance with that 
standard or the new standard at the option of 
the manufacturer until January 1, 1976. 

As issued. Standard No. 105-75 applied to 
passenger cars, trucks, buses, and multipurpose 
passenger vehicles (MPV's) equii)ped with hy- 
draulic brake systems. Its scheduled effective 
date was September 1, 1975. Thirteen petitions 
for rulemaking to postpone or revoke the stand- 
ard were filed with the NHTSA earlier this year. 
Following a comprehensive evaluation of the 
petitions, the NHTSA proposed and made final 
an indefinite delay of the standard as it applied 
to trucks, buses, and MPV's (40 F.R. 1048.3, 
March 6, 1975; 40 F.R. 18411, April 28, 1975). 

At the same time, the agency denied petitions 
for substantial postponement or revocation of the 
standard as it applies to passenger cars, having 
considered the cost of compliance for those ve- 
hicles, and having determined that significant 
safety benefit will derive from better stopping 
performance, stability, and pedal force levels (40 
F.R. 10483, March 6. 1975). A discussion of the 
potential benefits accompanied that decision. An 
economic evaluation of the impact of the standard 
will be available in the public docket. The only 
revisions of the standard proposed by the NHTSA 
were an interim pedal force value and a 4-month 
delay of effective date, to permit some flexibility 
in new model introduction dates where technical 



changes or isolated compliance problems had not 
been resolved. 

Manufacturer comments on the proposal were 
generally unresponsive to the proposed delay of 
four months and the interim pedal force value of 
110 pounds in wet recovery stops. The Vehicle 
Equipment Safety Commission considered the 
proposed pedal force \alues to be overgenerous. 
Chrysler Corporation indicated its support for 
the 4-month delay and interim value but em- 
phasized other arguments in its submission. Gen- 
eral Motors requested that the pedal force value 
be made permanent. It appears that manufac- 
turers support the short delay and pedal force 
modification to simplify introduction of the 1976 
models. Accordingly, the standard is modified 
as proposed, to establish an amended effective 
date of January 1, 1976, and a pedal force in- 
crease of 60 pounds up to a total of 110 poimds 
(in S5.1.5.2) until September 1, 1976. 

The majority of comments restated manufac- 
turer positions on the issue of substantial delay 
or revocation of the standard for passenger cars. 
Tlie NHTSA lias already considered this issue 
and, as noted above, concluded that the benefits 
of improved stopping performance, stability, and 
pedal force values outweigh the costs of imple- 
mentation. Manufacturers submitted no new data 
that would justify a reversal of NHTSA's earlier 
decision. 

Although the NHTSA limited its proposal to 
ii choice between tlie effective dates of September 
1. 1975, and January 1, 1976. several manufac- 
turers compared the cost savings of a short delay 
to January 1, 1976, with a substantially longer 
delay to September 1, 1976. Actually, the Jan- 
uary 1 date was proposed in order to ease the 
introduction of new models after September 1, 



PART 571 ; S 105— PRE 29 



EffecHve: June 9, 1975 



1975, and was not proposed as a means of re- 
ducing costs. The proposal was largely in re- 
sponse to manufacturers' comments that some 
1976 models would be introduced substantially 
later than normal so that 1975 model production 
might be extended beyond September 1, 1975. 
The NHTSA believes that the three years of lead- 
time since promulgation of Standard No. 105-75 
have been sufficient to permit the design and test- 
ing of complying brake systems in nearly all 
cases. With the 4-month transitional period, a 
manufacturer will be free to introduce the new 
brake systems along with its new model introduc- 
tion, as dictated by the economic situation of the 
automotive industry. 

Ford and Chrysler suggested that the standard 
could be improved by reduced loading during 
brake fade testing. These companies argue that 
present-day brake balance must be modified to 
meet the brake-fade and fourth effectiveness test 
of Standard No. 105-75 and that the new balance 
is not optimum. Agency testing demonstrates 
that many present-day vehicles can in fact meet 
the requirements as their brakes are balanced 
and suggests that major departures from current 
brake balance design will generally not be re- 



quired to comply with fade requirements under 
the present test conditions. The NHTSA accord- 
ingly concludes that tlie presently-specified load- 
ing does not i-esult in characteristics which would 
justify delay of the standard and the consequent 
loss of benefits during the period of delay. 

In consideration of the foregoing, Standard 
No. 105-75 (49 CFR 571.105-75) is amended 

Effective date: The date on which Standard 
No. 105-75 becomes mandatory for all passenger 
cars is January 1, 1976. However, the effective 
date of the amendments to both Standard No. 
105-75 and Standard No. 105 is June 9, 1975, and 
passenger cars manufactured between that date 
and January 1, 1976, may conform to either 
standard at the discretion of the manufacturer. 

(Sec. 103, 119, Pub. L. 89-563, 80 Stat. 718 (15 
U.S.C. 1392, 1407) ; delegation of authority at 
49 CFR 1.51.) 



Issued on June 5, 1975. 



James B. Gregory 
Administrator 

40 F.R. 24525 
June 9, 1975 



PART 571 ; S 105— PRE 30 



Effective: September 17, 1975 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 

Hydraulic Brake Systems 
(Docket No. 70-27; Notice 16) 



This notice responds to three petitions for 
reconsideration of recent amendments of Stand- 
ard No. 105-75, Hydraulic brake systems, 49 CFR 
571.105-75 (40 F.R. 11584, March 12, 1975) 
(Notice 13). The petitions requested clarifica- 
tion of new language that specifies minimum 
control force application values (S5.1.4.3(a) (2) 
and S5.1.5.2(a) (2) ) and objected to the NHTSA 
decision to defer for 1 year the requirement for 
a brake fluid level indicator in passenger cars. 

AVagner Electric Corporation requested clari- 
fication of the description of minimum permis- 
sible control force application value, which reads, 
"A minimum of 10 pounds or 40 percent (which- 
ever is greater) less than the average control 
force for the baseline check (but in no case less 
than 5 pounds)." Starting with a baseline 
value, the manufacturer must utilize the lower 
of two values which result when different 
amounts are subtracted from the baseline value. 
Because there is some ambiguity in the language 
used to describe these calculations, the NHTSA 
hereby revises the language to improve its clar- 
ity. The new wording in no way modifies the 
meaning of S5.1.4.3(a) (2) and S5.1.5.2(a) (2). 

Ford Motor Company, Wagner, and Meicedes- 
Benz requested reconsideration of the decision to 
defer for 1 year the requirement of S5.3.1 (b) 
that specifies a brake fluid level indicator. Ford 
and AVagner requested that the indicator be 
permanently deleted from the requirements in 
view of expense and reliability problems, claim- 
ing that its function is adequately served by the 
pressure differential warning that is also re- 
quired by the standard. 

The fluid level indicator detects and signals a 
loss of fluid from the system, whether the loss is 
swift or gradual. In the event of such a dan- 



gerous condition, the vehicle operator is warned 
early that braking function will be lost in the 
future. Unlike the pressure differential indi- 
cator, the fluid level indicator warns the oper- 
ator before one subsystem is effectively depleted 
of all fluid, and permits a repair to be under- 
taken before braking is lost. The indicator 
would also signal leakage at a wheel C5dinder 
which could contaminate brake linings and 
create a side-to-side imbalance in braking. 

At the same time, the petitions raise questions 
about the "reliability, availability, and cost of 
these devices that cannot be answered without 
further data. The NHTSA is in the process of 
gathering these data, and for this reason is un- 
able to respond to these two petitions within the 
120-day period established for actions on peti- 
tions for reconsideration. The NHTSA antici- 
pates publication of its response no later than 
October 31, 1975. 

Mercedes-Benz argued that the 1-year deferral 
of the brake fluid level indicator discriminated 
against those manufacturers who presently pro- 
vide such a device to meet the present Standard 
No. 105 (49 CFR 571.105). As interpreted, 
Standard No. 105 specifies a pressure differential 
indicator (used by most manufacturers) or a 
fluid level indicator (used by Mercedes) to signal 
a complete hydraulic-type failure of a partial 
system. Mercedes asked tliat the new standard 
be modified to continue this manufacturer option 
until both systems are required, reasoning that 
either system provides an equal safety benefit. 

As noted in the earlier discussion, a review of 
the benefits found in one warning indicator that 
are not found in the other demonstrates that 
there are separate and significant benefits in each 
warning. The new hydraulic brake standard 



PART 571; S 105— PRE 31 



fffeclive: September 17, 1975 



specifies botli warnings for tliis reason. The 
fluid level indicator was deferred only because 
of unresolved reliability and availability issues. 
The pressure differential indicator is a proven 
and available device which can be incorporated 
in vehicles at reasonable cost. While the NHTSA 
does not wish to encourage removal of Mercedes' 
fluid level indicator, it has decided that all pas- 
senger cars should be equipped witli the pressure 
differential indicatoi. For these reasons, Mer- 
cedes' petition is denied. 

In an area unrelated to the rulemaking which 
underlies this response to petitions for reconsid- 
eration. Toyota ^lotor Sales, Inc., has requested 
confirmation that S5.3.2 of the standard requires 
a check of tlie brake system indicator lamp func- 
tion only wjicn tlie transmission shift lever is in 
the "P" (park) or "X" (neutral) position (in 
the case of vehicles with automatic transmis- 
sion). The literal wording of S5.3.2 requires a 
check of lamp function without regard to the 
position of the transmission shift lever, whenever 
the ignition switch is turned txj the "on" position 
when the engine is not running, or when the 
ignition switch is in a position between "on" and 
"start" that is designated by the manufacturer 
as a check position. In the case of vehicles with 
an automatic transmission, however, this word- 
ing does not reflect the NHTSA's intent with 



respect to the check function. To properly re- 
flect this intent, the language of 85.3.2 is hereby 
modified in accordance with Toyota's request. 
This is an interpretative ruling, adding no addi- 
tional burden on any person, concerning which 
the XHT8A finds that notice and opportunity 
for conmient are unnecessary, under provisions 
of the Administrative Procedures Act (5 U.S.C. 
§ 553(b) (3) (A)). 

In a separate area, the date of September 1, 
1975, appearing in S7.4.2.1 of the standard is 
changed to January 1, 1976, to conform to the 
standard's new effective date. 

In consideration of the foregoing. Standard 
Xo. 105-75 (49 CFR 571.10.5-75) is amended. . . . 

Ejfecthie date: September 17, 1975. Because 
this amendment relieves a restriction and im- 
poses no additional burden on any person, it is 
found for good cause shown that an immediate 
effective date is in the public interest. 

(Sec. 103, 119 Pub. L. 89-563, 80 Stat. 718 
(15 U.S.C. 1392, 1407) ; delegation of authority 
at 49 CFR 1.51.) 

Issued on September 11, 1975. 

James B. Gregory 
Administrator 

40 F.R. 42872 
September 17, 1975 



PART 571 ; S 105— PRE 32 



EfFecllve: September 17, 1975 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 



Hydraulic Brake Systems 
(Docket No. 70-27, Notice 16) 



This notice responds to three petitions for 
reconsideration of recent amendments of Stand- 
ard No. 105-75, Hydraulic brake systems, 49 CFR 
571.105-75 (40 F.R. 11584, March 12, 1975) 
(Notice 13). The petitions requested clarifica- 
tion of new language that specifies minimum 
control force application values (S5.1.4.3(a) (2) 
and S5.1.5.2(a) (2) ) and objected to the NHTSA 
decision to defer for 1 year the requirement for 
a brake fluid level indicator in passenger cars. 

Wagner Electric Corporation requested clari- 
fication of the description of minimum permis- 
sible control force application value, which reads, 
"A minimum of 10 pounds or 40 percent (which- 
ever is greater) less than the average control 
force for the baseline check (but in no case less 
than 5 pounds)." Starting with a baseline 
value, the manufacturer must utilize the lower 
of two values which result when diflFerent 
amounts are subtracted from the baseline value. 
Because thei-e is some ambiguity in the language 
used to describe these calculations, the NHTSA 
hereby revises the language to improve its clar- 
ity. The new wording in no way modifies the 
meaning of S5.].4.3(a) (2) and S5.1.5.2(a) (2). 

Ford Motor Company, Wagner, and Mercedes- 
Benz requested reconsideration of the decision to 
defer for 1 year the requirement of S5.3.1(b) 
that specifies a brake fluid level indicator. Ford 
and Wagner requested that the indicator be 
permanently deleted from the requirements in 
view of expense and reliability problems, claim- 
ing that its function is adequately served by the 
pressure differential warning that is also re- 
quired by the standard. 

The fluid level indicator detects and signals a 
loss of fluid from the system, whether the loss is 
swift or gradual. In the event of such a dan- 



gerous condition, the vehicle operator is warned 
early that braking function will be lost in the 
future. Unlike the pressure differential indi- 
cator, the fluid level indicator warns the oper- 
ator before one subsystem is effectively depleted 
of all fluid, and permits a repair to be under- 
taken before braking is lost. The indicator 
would also signal leakage at a wheel cylinder 
which could contaminate brake linings and 
create a side-to-side imbalance in braking. 

At the same time, the petitions raise questions 
about the "reliability, availability, and cost of 
these devices that cannot be answered without 
further data. The NHTSA is in the process of 
gathering these data, and for this reason is un- 
able to respond to these two petitions within the 
120-day period established for actions on peti- 
tions for reconsideration. The NHTSA antici- 
pates publication of its response no later than 
October 31, 1975. 

Mercedes-Benz argued that the 1-year deferral 
of the brake fluid level indicator discriminated 
against those manufacturers who presently pro- 
vide such a device to meet the present Standard 
No. 105 (49 CFR 571.105). As interpreted. 
Standard No. 105 specifies a pressure differential 
indicator (used by most manufacturers) or a 
fluid level indicator (used by Mercedes) to signal 
a complete hydraulic-type failure of a partial 
system. Mercedes asked that the new standard 
be modified to continue this manufacturer option 
until both systems are required, reasoning that 
either system provides an equal safety benefit. 

As noted in the earlier discussion, a review of 
the benefits found in one warning indicator that 
are not found in the otlier demonstrates that 
there are separate and significant benefits in each 
warning. The new hydraulic brake standard 



PART 571; S 105— PRE 31 



fffective: September 17, 1975 



specifies both warnings for tliis reason. The 
fluid level indicator was deferred only because 
of unresolved reliability and availability issues. 
The pressure differential indicator is a proven 
and available device which can be incorporated 
in vehicles at reasonable cost. While the NHTSA 
does not wish to encourage removal of Mercedes' 
fluid level indicator, it has decided that all pas- 
senger cars should be equipped witli the pressure 
differential indicatoi. For these reasons, Mer- 
cedes* petition is denied. 

In an area unrelated to the rulemaking which 
underlies this response to petitions for reconsid- 
eration. Toyota Motor Sales, Inc., has requested 
confirmation that So. 3.2 of the standard requires 
a check of the brake system indicator lamp func- 
tion only when the transmission shift lever is in 
the "P" (park) or "N" (neutral) position (in 
the case of vehicles with automatic transmis- 
sion). The literal wording of S5.3.2 requires a 
check of lamp function without regard to the 
position of tlie transmission shift lever, whenever 
the ignition switch is turned to the "on" position 
when the engine is not running, or when the 
ignition switch is in a position between "on" and 
"start" that is designated by the manufacturer 
as a check position. In the case of vehicles with 
an automatic transmission, however, this word- 
ing does not reflect the XHTSA's intent with 



respect to the check function. To properly re- 
flect this intent, the language of 85. 3.2 is hereby 
modified in accordance with Toyota's request. 
Tiiis is an interpretative ruling, adding no addi- 
tional burden on any person, concerning which 
the XHT8A finds that notice and opportunity 
for conunent are unnecessary, under provisions 
of the Administrative Procedures Act (5 U.S.C. 
§ 5.53(b) (3) (A)). 

In a separate area, the date of September 1, 
1975, appearing in S7.4.2.1 of the standard is 
changed to January 1, 1376, to conform to the 
standard's new effective date. 

In consideration of the foregoing. Standard 
Xo. 105-75 (49 CFR 571.105-75) is amended. . . . 

Effectwe date: September 17, 1975. Because 
this amendment relieves a restriction and im- 
poses no additional burden on any person, it is 
found for good cause shown that an immediate 
effective date is in the public interest. 

(Sec. 103, 119 Pub. L. 89-563, 80 Stat. 718 
(15 U.S.C. 1392, 1407); delegation of authority 
at 40 CFR 1.51.) 

Issued on September 11, 1975. 

James B. Gregory 
Administrator 

40 F.R. 42872 
September 17, 1975 



PART 571; S 105— PRE 32 



MOTOR VEHICLE SAFETY STANDARD NO. 105 



Hydraulic Brake Systems 



51. Scope. This standard specifies require- 
ments for hydraulic service brake and associated 
parking brake systems. 

52. Purpose. The purpose of this standard is to 
insure safe braking performance under normal and 
emergency conditions. 

[S3. Application. This standard applies to 
passenger cars, multipurpose passenger vehicles, 
trucks, and buses with hydraulic service brake 
systems. (46 F.R. 55-January 2, 1981. Effective: 
9/1/83)1 

S4. Definitions. "Antilock system" means a 
portion of a service brake system that automatically 
controls the degree of rotational wheel sUp at one or 
more road wheels of the vehicle during braking. 

"Backup system" means a portion of a service 
brake system, such as a pump, that supplies energy 
in the event of a primary brake power source 
failure. 

"Brake power assist unit" means a device installed 
in a hydraulic brake system that reduces the operator 
effort required to actuate the system, and that if 
inoperative does not prevent the operator from 
braking the vehicle by a continued application of 
muscular force on the service brake control. 

"Brake power unit" means a device installed in a 
brake system that provides the energy required to 
actuate the brakes, either directly or indirectly 
through an auxiliary device, with the operator 
action consisting only of modulating the energy 
application level. 

"Hydraulic brake system" means a system that 
uses hydraulic fluid as a medium for transmitting 



force from a service brake control to the 
service brake, and that may incorporate a brake 
power assist unit, or a brake power unit. 

"Initial brake temperature" means the average 
temperature of the service brakes on the hottest 
axle of the vehicle 0.2 miles before any brake 
application. 

["Lightly loaded vehicle weight" means: 

(a) for vehicles with a GVWR of 10,000 
pounds or less, unloaded vehicle weight plus 400 
pounds (including driver and instrumentation); 

(b) for vehicles with a GVWR greater than 
10,000 pounds, unloaded vehicle weight plus 500 
pounds (including driver and instrumentation). (46 
F.R. 55-January 2, 1981. Effective: 9/1/83)1 

"Parking mechanism" means a component or 
subsystem of the. drive train that locks the drive 
train when the transmission control is placed in 
a parking or other gear position and the ignition 
key is removed. 

"Pressure component" means a brake system 
component that contains the brake system fluid 
and controls or senses the fluid pressure. 

"Skid number" means the frictional resistance 
of a pavement measured in accordance with 
American Society for Testing and Materials 
(ASTM) Method E-274-70 (as revised July, 
1974) at 40 mph, omitting water delivery as 
specified in paragraphs 7.1 and 7.2 of that 
method. 

"Snub" means the braking deceleration of a 
vehicle from a higher reference speed to a lower 
reference speed that is greater than zero. 

"Spike stop" means a stop resulting from the 
application of 200 pounds of force on the service 
brake control in 0.08 second. 



(Rev. 1/2/81) 



PART 571; S 105-1 



"Split service brake system" means a brake 
system consisting of two or more subsystems ac- 
tuated by a single control designed so that a 
leakage-type failure of a pressure component in a 
single subsystem (except structural failure of a 
housing that is common to two or more sub- 
systems) shall not impair the operation of any 
other subsystem. 

"Stopping distance" means the distance trav- 
eled by a vehicle from the point of application of 
force to the brake control to the point at which the 
vehicle reaches a full stop. 

"Variable proportioning brake system" means a 
system that automatically adjusts the braking 
force at the axles to compensate for vehicle static 
axle loading and/or dynamic weight transfer be- 
tween axles during deceleration. 

S5. Requirements. 

|S5.1 Service brake systems. Each passenger 
car and each multipurpose passenger vehicle, 
truck, and bus with a GVWR of 10,000 lbs. or less, 
and each school bus with a GVWR of greater than 
10,000 lbs. shall be capable of meeting the re- 
quirements of S5.1.1 through S5.1.6 under the con- 
ditions prescribed in S6, when tested according to 
the procedures and in the sequence set forth in S7. 
Each multipurpose passenger vehicle, truck, and 
bus (other than a school bus) with a GVWR greater 
than 10,000 lbs. shall meet the requirements of 
S5.1.2 and S5.1.3 under the conditions specified in 
S6 when tested according to the procedures and in 
the sequence set forth in S7. Except as noted in 
S5.1.1.2 and S5. 1.1.4, if a vehicle is incapable of at- 
taining a speed specified in S5.1.1, S5.1.2, S5.1.3, 
or S5.1.6, its service brakes shall be capable of 
stopping the vehicle from the multiple of 5 mph 
that is 4 to 8 mph less than the speed attainable in 2 
mOes, within distances that do not exceed the cor- 
responding distances specified in Table II. If a 
vehicle is incapable of attaining a speed specified in 
S5.1.4 in the time or distance interval set forth, it 
shall be tested at the highest speed attainable in 
the time or distance interval specified. (46 F.R. 
55-January 2, 1981. Effective: 9/1/83)1 

[S5.1.1 Stopping distance. The service brakes 
shall be capable of stopping each vehicle, other 
than a vehicle which both has a GVWR of not less 
than 8,000 pounds and not greater than 10,000 
pounds and is not a school bus, in four effec- 



tiveness tests within the distances and from the 
speeds specified in 85. 1.1.1, S5. 1.1.2, 85. 1.1.3, and 
85.1.1.4. The service brakes shall be capable of 
stopping each vehicle which both has a GVWR of 
not less than 8,000 pounds and not greater than 
10,000 pounds and is not a school bus, in three ef- 
fectiveness tests within the distances and from the 
speeds specified in 85.1.1.1, 85.1.1.2, and 85.1.1.4. 
(46 F.R. 55-January 2, 1981. Effective: 9/1/83)1 

85.1 .1 .1 In the first (prebumished) effectiveness 
test, the vehicle shall be capable of stopping from 
30 mph and 60 mph within the corresponding 
distances specified in Column I of Table II. 

[85.1.1.2 In the second effectiveness test, the 
vehicle shall be capable of stopping from 30 and 60 
mph within the corresponding distances specified 
in Column II of Table II. If the speed attainable in 
2 miles is not less than 84 mph, a passenger car or 
other vehicle with a GVWR of 10,000 pounds or 
less shall also be capable of stopping from 80 mph 
within the corresponding distances specified in 
Column II of Table II. (46 F.R. 55-January 2, 
1981. Effective: 9/1/83)1 

85.1 .1 .3 In the third effectiveness test the vehi- 
cle shall be capable of stopping at lightly loaded 
vehicle weight from 60 mph within the correspond- 
ing distance specified in Column III of Table II. 

85.1 .1 .4 In the fourth effectiveness test, a vehi- 
cle with a GVWR of 10,000 pounds or less shall be 
capable of stopping from 30 and 60 mph within the 
corresponding distances specified in Column I of 
Table II. If the speed attainable in 2 miles is not 
less than 84 mph, a passenger car [or other vehicle 
with a GVWR of 10,000 lbs. or lessl shall also be 
capable of stopping from 80 mph within the cor- 
responding distance specified in Column I of Table 
II. (46 F.R. 55-January 2, 1981. Effective: 
9/1/83) 

If the speed attainable in 2 miles is not less than 
99 mph, a passenger car shall, in addition, be 
capable of stopping from the applicable speed in- 
dicated below, within the corresponding distance 
specified in Column I of Table II. 



Speed attainable 
in 2 miles (mph) 

not less than 99 but 
less than 104 

104 or more 



Required to 
stop from, (mph) 

95 
100 



(Rw. 1/2/81) 



PART 571; S 105-2 



Table I-BRAKE TEST PROCEDURE SEQUENCE AND REQUIREMENTS 



No 


Sequence 


Test Load 


Test 
Procedure 


Require- 




Light 


GVWR 


ments 


1. 


TnRtnimf>ntJit.ion oheck 




X 
X 
X 
X 
X 

X 
X 
X 
X 
X 
X 
X 
X 
X 

X 


S7.2 

S7.3 

S7.4 

S7.5 

S7.6 

S7.7 

S7.8 

S7.9 

S7.10 

S7.ll 

S7.12 

S7.13 

S7.14 

S7.15 

S7.16 

S7.17 

S7.18 

S7.19 




2. 
3. 


First (prebumish) effectiveness test 

Riimish procedure 


- 


S5.1.1.1 


4. 


Second effectiveness 


_ 


S5.1.1.2 


5. 


First rebumish 


_ 


_ 


6. 


Parking brake 


X 


S5.2 


7. 


Third effectiveness (ligbtly loaded vehicle) 


X 


S5.1.1.3 


8. 


Partial failure 


X 


S5.1.2 


9. 


Inoperative brake power and power assist units _ 


_ 


S5.1.3 


10. 
11. 


First fade and recovery 
Second rebumish 


- 


S5.1.4 


12. 
13. 


Second fade and recovery 
Third rebumish 


- 


S5.1.4 


14. 


Fourth effectiveness 


_ 


S5.1.1.4 


15. 
16. 
17. 


Water recovery 
Spike stops 
Final inspection 


~ 


S5.1.5 
S5.1.6 
S5.6 


18. 


Moving barrier test 


_ 


S5.2.2.3 










S5.1.2 Partial failure. 


of the manufacturer). (46 


i F.R. 55- 


-January 2, 



55.1.2.1 In vehicles manufactured with a split 
service brake system, in the event of a rupture or 
leakage type of failure in a single subsystem, other 
than a structural failure of a housing that is com- 
mon to two or more subsystems, the remaining 
portion(s) of the service brake system shall con- 
tinue to operate and shall be capable of stopping a 
vehicle from 60 mph within the corresponding 
distance specified in Column IV of Table II. 

55.1.2.2 In vehicles not manufactured with a 
split service brake system, in the event of any one 
rupture or leakage type of failure in any compo- 
nent of the service brake system the vehicle shall, 
by operation of the service brake control, be 
capable of stopping 10 times consecutively from 60 
mph within the corresponding distance specified in 
Column IV of Table II. 

[S5.1.3 Inoperative brake power assist unit or 
brake power unit. A vehicle equipped with one or 
more brake power assist units shall meet the re- 
quirements of either S5.1.3.1, S5.1.3.2, or S5.1.3.4 
(chosen at the option of the manufacturer), and a 
vehicle equipped with one or more brake power 
units shall meet the requirements of either 
S5.1.3.1, S5.1.3.3, or S5.1.3.4 (chosen at the option 



1981. Effective: 9/1/83)1 

55.1.3.1 The service brakes on a vehicle 
equipped with one or more brake power assist 
units or brake power units, with one such unit 
inoperative and depleted of all reserve capability, 
shall be capable of stopping a vehicle from 60 mph 
within the corresponding distance specified in 
Column IV of Table II. 

55.1.3.2 Brake power assist units. The service 
brakes on a vehicle equipped with one or more 
brake power assist units, with one such unit in- 
operative, shall be capable of stopping a vehicle 
from 60 mph— 

(a) In six consecutive stops at an average 
deceleration for each stop that is not lower than 
that specified in Column I of Table III, when the in- 
operative unit is not initially depleted of all reserve 
capability; and 

[(b) In a final stop, at an average deceleration 
that is not lower than 7 fpsps for passenger cars 
(equivalent stopping distance 554 feet) or 6 fpsps 
for vehicles other than passenger cars (equivalent 
stopping distance 646 feet), as applicable, when the 
inoperative unit is depleted of all reserve capac- 



I 



(Rev. 1/2/81) 



PART 571; S 105-3 



[Table II-STOPPING DISTANCES 



STOPPING DISTANCE IN FEET FOR TESTS INDICATED 



I 



II 



III 



IV 



Vehicle test 1st (prebumish) Inoperative brake power 

speed and 4th effectiveness: 3d (lightly loaded vehicle) and power assist unit; 

(miles per spike effectiveness check 2d effectiveness effectiveness partial failure 

hour) (a) (b) (c) (d) (a) (b)and(c) (d) (a) (b) (c) (d) (a) (b)and(c) (d) 

30 '57 »65 '269(lst) '88 '54 '57 '81 51 57 65 81 114 130 170 

'265(4th 

and 
spike) 

'72 

35 74 83 91 132 70 74 132 67 74 83 132 155 176 225 

40 96 108 119 173 91 96 173 87 96 108 173 202 229 288 

45 121 137 150 218 115 121 218 110 121 137 218 257 291 358 

50 150 169 185 264 142 150 264 135 150 169 264 317 359 435 

55 181 204 224 326 172 181 326 163 181 204 326 383 433 530 

60 '216 '242 '267 '388 '204 ' 216 ' 388 ' 194 ' 216 ' 242 ' 388 ' 456 ' 517 ' 613 

80 '405 '459 '510 NA '383 NA NA NA NA NA NA NA NA NA 

95 '607 NA NA NA NA NA NA NA NA NA NA NA NA NA 

100 '673 NA NA NA NA NA NA NA NA NA NA NA NA NA 

' Distances for specified. ^ Applicable to school buses only. NA = Not applicable. 

Note— (a) passenger cars; (b) vehicles other than passenger cars with GVWR of less than 8,000 lbs; (c) vehicles with GVWR of 

not less than 8,000 lbs. and not more than 10,000 lbs.; (d) vehicles with GVWR greater than 10,000 lbs. (46 F.R. 55-January 2, 1981. 
Effective: 9/1/83)1 



ITable III-INOPERATIVE brake POWER ASSIST AND BRAKE POWER UNITS 



Average Deceleration, FPSPS 



EquivEilent Stopping Distance, Feet 



Stop. No. 



Column 1 


—brake 


Column 2 


—brake 


Column 3 


1— brake 


Column 4 


—brake 


power 


assist 


power 


unit 


power 


assist 


power 


unit 


(a) 


(b) and (c) 


(a) 


(b) and (c) 


(a) 


(b) and (c) 


(a) 


(b) and (c) 


16.0 


14.0 


16.0 


13.0 


242 


277 


242 


298 


12.0 


12.0 


13.0 


11.0 


323 


323 


298 


352 


10.0 


10.0 


12.0 


10.0- 


388 


388 


323 


388 


9.0 


8.5 


11.0 


9.5 


431 


456 


352 


409 


8.0 


7.5 


10.0 


9.0 


484 


517 


388 


431 


7.5 


6.7 


9.5 


8.5 


517 


580 


409 


456 


'7.0 


'6.0 


9.0 


8.0 


554 


646 


431 


484 


NA 


NA 


8.5 


7.5 


NA 


NA 


456 


517 


NA 


NA 


8.0 


7.0 


NA 


NA 


484 


554 


NA 


NA 


7.5 


6.5 


NA 


NA 


517 


596 


NA 


NA 


'7.0 


'6.0 


NA 


NA 


554 


646 



1 . 

2 . 

3 . 

4 . 

5 . 

6 . 

7 . 

8 . 

9 . 
10 
11 



' Depleted, (a) passenger cars; (b) vehicles other than passenger cars with GVWR of 10,000 lbs. or less; (c) vehicles with GVWR 
greater than 10,000 lbs.; NA=Not Applicable. (46 F.R. 55-January 29, 1981. Effective: 9/1/83)1 



(Rev. 1/2/81) 



PART 571; S 105-4 



I 



ity. (46 F.R. 55-January 2, 1981. Effective: 
9/1/83)1 

55.1.3.3 Brake power units. The service brakes 
of a vehicle equipped with one or more brake power 
units with an accumulator-type reserve system, 
with any one failure in any one unit, shall be 
capable of stopping the vehicle from 60 mph: 

(a) In 10 consecutive stops at in average 
deceleration for each stop that is not lower than 
that specified in Column II of Table III, when the 
unit is not initially depleted of all reserve capability; 
and 

[(b) In a final stop, at an average deceleration 
that is not lower than 7 fpsps for passenger cars 
(equivalent stopping distance 554 feet) or 6 fpsps 
for vehicles other than passenger cars (equivalent 
stopping distance 646 feet), as applicable, when the 
inoperative unit is depleted of all reserve capacity. 
(46 F.R. 55-January 2, 1981. Effective: 9/1/83)1 

55.1.3.4 Brake power assist and brake power 
units. The service brake of a vehicle equipped 
with one or more brake power assist units or brake 
power imits with a backup system, with one brake 
power assist unit or brake power unit inoperative 

I and depleted of all reserve capability and with only 
the backup system operating in the failed sub- 
system, shall be capable of stopping the vehicle 
from 60 mph in 15 consecutive stops at an average 
deceleration for each stop that is not lower than 12 
fpsps (equivalent stopping distance 323 feet). 

S5.1.4 Fade and recovery. The service brakes 
shall be capable of stopping each vehicle in two 
fade and recovery tests as specified below. 

55.1 .4.1 The control force used for the base line 
check stops or snubs shall be not less than 10 
pounds, nor more than 60 pounds, except that the 
control force for a vehicle with a GVWR of 10,000 
pounds or more may be between 10 pounds and 90 
pounds. 

55.1.4.2 (a) Each vehicle with GVWR of 10,000 
pounds or less shall be capable of making five fade 
stops (10 fade stops on the second test) from 60 
mph at a deceleration not lower than 15 fpsps for 
each stop, followed by five fade stops at the max- 
imum decleration attainable from 5 to 15 fpsps. 

(b) Each vehicle with a GVWR greater than 
10,000 pounds shall be capable of making 10 fade 



snubs (20 fade snubs on the second test) from 40 
mph to 20 mph at 10 fpsps for each snub. 

S5.1.4.3 (a) Each vehicle with a GVWR of 
10,000 pounds or less shall be capable of making 
five recovery stops from 30 mph at ten fpsps for 
each stop, with a control force application that falls 
within the following maximum and minimum 
limits: 

(1) A maximum for the first four recovery 
stops of 150 pounds, and for the fifth stop, of 20 
pounds more than the average control force for 
the baseline check; and 

(2) A minimum of— 

(A) The average control force for the 
baseline check minus 10 pounds, or 

(B) The average control force for the 
baseline check times 0.60, 

whichever result is lower (but in no case lower than 
5 pounds). 

(b) Each vehicle with a GVWR of more than 
10,000 pounds shall be capable of making five 
recovery snubs from 40 mph to 20 mph at 10 fpsps 
of each snub, with a control force application that 
falls within the following maximum and minimum 
limits: 

(1) A maximum for the first four recovery 
snubs of 150 pounds, and for the fifth snub, of 20 
pounds more than the average control force for 
the baseline check (but in no case more than 100 
pounds); and 

(2) A minimum of— 

(A) The average control force for the 
baseline check minus 10 pounds, or 

(B) The average control force for the 
baseline check times 0.60, whichever is lower 
(but in no case lower than 5 pounds). 

S5.1 .5 Water recovery. The service brakes shall 
be capable of stopping each vehicle in a water 
recovery test, as specified below. 

55.1.5.1 The control force used for the baseline 
check stops or snubs shall be not less than 10 
pounds, nor more than 60 pounds, except that the 
control force for a vehicle with a GVWR of 10,000 
pounds or more may be between 10 and 90 pounds. 

55.1.5.2 (a) After being driven for 2 minutes 
at a speed of 5 mph in any combination of for- 
ward and reverse directions through a trough 
having a water depth of 6 inches, each vehicle 
with a GVWR of 10,000 pounds or less shall be 



(Rev. 1/2/81) 



PART 571; S 105-5 



(b) If a single common indicator is used, the 
lamp shall display the word "Brake". The letters 
and background of a single common indicator shall 
be of contrasting colors, one of which is red. 

(c) (1) If separate indicator lamps are used for 
one or more than one of the functions described in 
S5.3.1(a) through S5.3.1(d), the display shall, 
except as provided in (c)(1)(A) through (D) of this 
section, include the word "Brake" and appropriate 
additional labeling. 

(A) If a separate indicator lamp is provided for 
gross loss of pressure, the words "Brake 
Pressure" shall be used for S5.3.1(a). 

(B) If a separate indicator lamp is provided for 
low brake fluid, the words "Brake Fluid" shall be 
used for S5.3.1(b), except for vehicles using 
hydraulic system mineral oil. 

(C) If a separate indicator lamp is provided for 
an anti-lock system, the single word "Antilock" or 
"Anti-lock" may be used for S5.3.1(c). 

(D) If a separate indicator lamp is provided for 
application of the parking brake, the single word 
"Park" may be used for S5.3.1(d). 

(2) Except for a separate indicator lamp for an 
anti-lock system, the letters and background of 
each separate indicator lamp shall be of con- 
trasting colors, one of which is red. The letters and 
background of a separate indicator lamp for an 
anti-lock system shall be of contrasting colors, one 
of which is yellow. (49 F.R. 30191-July 27, 1984. 
Effective: July 27, 1984)1 

S5.4 Reservoirs. 

55.4.1 Master cylinder reservoirs. A master 
cylinder shall have a reservoir compartment for 
each service brake subsystem serviced by the 
master cylinder. Loss of fluid from one compart- 
ment shall not result in a complete loss of brake 
fluid from another compartment. 

55.4.2 Reservoir capacity. Reservoirs, whether 
for master cylinders or other type systems, shall 
have a total minimum capacity equivalent to the 
fluid displacement resulting when all the wheel 
cylinders or caliper pistons serviced by the reser- 
voirs move from a new lining, fully retracted posi- 
tion (as adjusted initially to the manufacturer's 
recommended setting) to a fully worn, fully applied 
position, as determined in accordance with 
S7. 18(c) of this standard. Reservoirs shall have 
completely separate compartments for each sub- 
system except that in reservoir systems utilizing a 
portion of the reservoir for a common supply to 
two or more subsystems, individual partial com- 
partments shall each have a minimum volume of 
fluid equal to at least the volume displaced by the 



master cylinder piston servicing the subsystem, 
during a full stroke of the piston. Each brake power 
unit reservoir servicing orJy the brake system shall 
have a minimum capacity equivalent to the fluid 
displacement required to charge the system piston(s) 
or accumulator(s) to normal operating pressure plus 
the displacement resulting when all the wheel 
cylinders or caliper pistons serviced by the reservoir 
or accumulator(s) move from a new lining fully 
retracted position (as ad- 

justed initially to the manufacturer's recommended 
setting) to a fully worn, fully applied position. 

S5.4.3 Reservoir labeling. Each vehicle shall 
have a brake fluid warning statement that reads as 
follows, in letters at least % of an inch high: 
"WARNING, Clean filler cap before removing. 

Use only fluid from 

a sealed container." (Inserting the recommended 
type of brake fluid as specified in 49 CFR 
§ 571.116, e.g., "DOT 3".) The lettering shaU be- 

(a) Permanently affixed, engraved, or embossed; 

(b) Located so as to be visible by direct view, 
either on or within 4 inches of the brake fluid reser- 
voir filler plug or cap; and 

(c) Of a color that contrasts with its background, 
if it is not engraved or embossed. 

55.5 Antilock and variable proportioning brake 
systems. In the event of failure (structural or func- 
tional) in an antilock or variable proportioning brake 
system the vehicle shall be capable of meeting the 
stopping distance requirements specified in S5.1.2 
for service brake system partial failure. 

55.6 Brake system integrity. Each vehicle shall 
be capable of completing all performance re- 
quirements of S5 without— 

(a) Detachment or fracture of any component of 
the braking system, such as brake springs and 
brake shoe or disc pad facing, other than minor 
cracks that do not impair attachment of the fric- 
tion facing. All mechanical components of the 
braking system shall be intact and functional. Fric- 
tion facing tearout (complete detachment of lining) 
shall not exceed 10 percent of the lining on any 
single frictional element. 

(b) Any visible brake fluid or lubricant on the 
friction surface of the brake, or leakage at the 
master cylinder or brake power unit reservoir 
cover, seal, and filler openings. 

S6. Test conditions. The performance re- 
quirements of S5 shall be met under the following 
conditions. Where a range of conditions is 
specified, the vehicle shall be capable of meeting 
the requirements at all points within the range. 



(Rev. 7/27/84) 



PART 571; S 105-8 



56.1 Vehicle weight. 

56.1 .1 Other than tests specified at lightly load- 
ed vehicle weight in S7.7, S7.8, and S7.9, the vehi- 
cle is loaded to its GVWR such that the weight on 
each axle as measured at the tireground interface 
is in proportion to its GAWR, except that [each) 
fuel tank is filled to any level from 100 percent of 
capacity (corresponding to full GVWR loading) to 
75 percent. (46 F.R. 55-January 2, 1981. Effec- 
tive: 9/1/83) 

However, if the weight on any axle of a vehicle at 
lightly loaded vehicle weight exceeds the axle's 
proportional share of the gross vehicle weight 
rating, the load required to reach GVWR is placed 
so that the weight on that axle remains the same as 
at lightly loaded vehicle weight. 

56.1 .2 For the applicable tests specified in S7.7, 
S7.8, and S7.9, vehicle weight is lightly loaded 
vehicle weight, with the added weight distributed 
in the front passenger seat area in passenger cars 
[multipurpose vehicles and trucks! and in the area 
adjacent to the driver's seat in buses. (46 F.R. 
55-January 2, 1981. Effective: 9/1/83) 

56.2 Test loads. Reserved. 

56.3 Tire inflation pressure. Tire inflation 
pressure is the pressure recommended by the vehi- 
cle manufacturer for the GVWR of the vehicle. 

56.4 Transmission selector control. For S7.3, 
S7.5, S7.8, S7.15, S7.17, S7.ll. 1.2, S7.11.2.2, 
S7.1 1.3.2, and as required for S7.13, the transmis- 
sion selector control is in neutral for all decelera- 
tions. For all other tests during all decelerations, 
the transmission selector is in the control position, 
other than overdrive, recommended by the 
manufacturer for driving on a level surface at the 
applicable test speed. To avoid engine stall during 
tests required to be nm in gear a manual transmis- 
sion may be shifted to neutral (or the clutch 
disengaged) when the vehicle speed decreases to 
20 mph. 

56.5 Engine. Engine idle speed and ignition 
timing settings are according to the manufac- 
tiirer's recommendations. If the vehicle is equipped 
with an adjustable engine speed governor, it is ad- 
justed according to the manufacturer's recommen- 
dation. 



56.6 Vehicle openings. All vehicle openings 
(doors, windows, hood, trunk, convertible top, 
cargo doors, etc.) are closed except as required for 
instrumentation purposes. 

56.7 Ambient temperature. The ambient 
temperature is any temperature between 32° F. 
and 100° F. 

56.8 Wind velocity. The wind velocity is zero. 

56.9 Road surface. Road tests are conducted 
on a 12-foot-wide, level roadway having a skid 
number of 81. Burnish stops are conducted on any 
surface. The parking brake test surface is clean, 
dry smooth Portland cement concrete. 

56.10 Vehicle position. The vehicle is aligned 
in the center of the roadway at the start of each 
brake application. Stops, other than spike stops, 
are made without any part of the vehicle leaving 
the roadway. Except as noted below, stops are 
made without lockup of any wheel at speeds 
greater than 10 mph. There may be controlled 
lockup on an antilock-equipped axle, and lockup of 
not more than one wheel per vehicle, uncontrolled 
by an antilock system. [Dual wheels on one side of 
an axle are considered a single wheel.) Locked 
wheels at speeds greater than 10 mph are allowed 
during spike stops (but not spike check stops), par- 
tial failure stops, and inoperative brake power or 
power assist unit stops. (46 F.R. 55— January 2, 
1981. Effective: 9/1/83) 

56.1 1 Thermocouples. The brake temperature 
is measured by plug-type thermocouples installed 
in the approximate center of the facing length and 
width of the most heavily loaded shoe or disc pad, 
one per brake, as shown in Figure 1 . A second ther- 
mocouple may be installed at the beginning of the 
test sequence if the lining wear is expected to 
reach a point causing the first thermocouple to 
contact the metal rubbing surface of a drum or 
rotor. For center-grooved shoes or pads, ther- 
mocouples are installed within one-eighth of an 
inch to one-quarter inch of the groove and as close 
to the center as possible. 



(Rev. 9/1/63) 



PART 571; S 105-9 




Ca DRILL NO 11 
QIOOIiMIMAN 
DEPTH BEFORE CRINO 



aixa II. oil RECESS 

UNDEn GROUND 



FIGURE 1 - TYPICAL PLUG THERMOCOUPLE INSTALLATrONS 
Not*: 7h» Mcond th*rmocoupl« shall be inttallad at 080 .nt*i 

deplh wilhm 1 inch ci>cuml«r*nt>«l(v of the tharmoeoupit 
■nttallad il .040 inch dapth. 



56.12 Initial brake temperature. Unless other- 
wise specified, the brake temperature is 150° F to 
200° F. 

56.13 Control forces. Unless otherwise 
specified, the force applied to a brake control is not 
less than 15 pounds and not more than 150 pounds. 

S7. Test procedures and sequence. Each vehi- 
cle shall be capable of meeting all the applicable re- 
quirements of S5 when testing according to the 
procedures and in the sequence set forth below, 
without replacing any brake system part or mak- 
ing any adjustments to the brake system other 
than as permitted in burnish and rebumish pro- 
cedures and in S7.9 and S7.10. [For vehicles only 
having to meet the requirements of S5.1.2 and 
S5.1.3 in section S5.1, the applicable test pro- 
cedures and sequence are S7.1, S7.2, S7.4, S7.9, 
S7.10, and S7.18. However, at the option of the 
manufacturer, the following test procedures and 
sequence maybe conducted: S7.1, S7.2, S7.3, S7.4, 
S7.5, S7.6, S7.7, S7.8, S7.9, S7.10 and S7.18. The 
choice of this option shall not be construed as add- 
ing to the requirements specified in S5.1.2 and 
S5.1.3. (48 F.R. 39939-September 2, 1983. Effec- 
tive: September 2, 1983)1 Automatic adjusters may 
be locked out, according to the manufacturer's 



recommendation, when the vehicle is prepared for 
testing. If this option is selected, adjusters must 
remain locked out for entire sequence of tests. A 
vehicle shall be deemed to comply wath the stop- 
ping distance requirements of S5.1 if at least one 
of the stops at each speed and load specified in each 
of S7.3, S7.5, S7.8, S7.9, S7.10, S7.15, or S7.17 
(check stops) is made writhin a stopping distance 
that does not exceed the corresponding distance 
specified in Table II. 

When the transmission selector control is re- 
quired to be in neutral for a deceleration, a stop or 
snub shall be obtained by the following procedures: 
(1) Exceed the test speed by 4 to 8 mph; (2) close 
the throttle and coast in gear to approximately 2 
mph above the test speed; (3) shift to neutral; and 
(4) when the test speed is reached, apply the serv- 
ice brakes. 

57.1 Brake warming. If the initial brake 
temperature for the first stop in a test procedure 
(other than S7.7 and S7.16) has not been reached, 
heat the brakes to the initial brake temperature by 
making not more than 10 snubs from not more 
than 40 mph to 10 mph, at a deceleration not 
greater than 10 fpsps. 

57.2 Pretest instrumentation check. Conduct a 
general check of instrumentation by making not 
more than 10 stops from & speed of not more than 
30 mph, or 10 snubs from a speed of not more than 
40 mph to 10 mph, at a deceleration of not more 
than 10 fpsps. If instrument repair, replacement, 
or adjustment is necessary, make not more than 10 
additional stops or snubs after such repair, replace- 
ment, or adjustment. 

57.3 Service brake system— first (rebumish) ef- 
fectiveness test. Make six stops from 30 mph. 
Then make six stops from 60 mph. 

57.4 Service brake system— burnisfi procedure. 

S7.4.1 
less. 



Vehicles with GVWR of 10,000 pounds or 



S7.4.1.1 Burnish. Burnish the brakes by mak- 
ing 200 stops from 40 mph at 12 fpsps (the 150 
poimd control force limit does not apply here). The 
interval from the start of one service brake ap- 
plication to the start of the next shall be either the 
time necessary to reduce the initial brake 
temperature to between 230° F and 270° F, or the 
distance of 1 mile, whichever occurs first. Ac- 
celerate to 40 mph after each stop and maintain 
that speed until making the next stop. 



(Rev. 9/2/83) 



PART 571; S 105-10 



S7.4.1.2 Brake adjustment— post burnish. 

After burnishing, adjust the brakes manually in ac- 
cordance with the manufacturer's recommenda- 
tion if the brake systems are manual or if the 
automatic adjusters are locked out, or by making 
stops as recommended by the manufacturer if the 
automatic adjusters are operative. 



S7.4.2 
pounds. 



Vehicles with GVWR greater than 10,000 



S7.4.2.1 Burnish. Burnish the brakes by mak- 
ing 500 snubs at 10 fpsps in the sequence specified 
in Table IV and within the speed ranges 
indicated. After each brake application ac- 
celerate to the next speed specified and maintain 
that speed until making the next brake application 
at a point 1 mile from the initial point of the 
previous brake application. If a vehicle cannot at- 
tain any speed specified in 1 mile, continue to ac- 
celerate until the speed specified is reached or until 
a point 1.5 miles from the initial point of the 
previous brake application is reached, whichever 
occurs first. If during any of the brake applica- 
tions specified in Table IV the hottest brake 
reaches 500° F, make the remainder of the 500 ap- 
plications from that snub condition, except that a 
higher or lower snub condition shall be followed (up 
to the 60 mph initial speed) as necesary to maintain 
a temperature of 500° F±50° F. 



Series 

1 
2 
3 

4 
5 





Table IV 


)nubs 


Snub conditions 




(highest speed indicated) 


175 


40 to 20 mph 


25 


45 to 20 mph 


25 


50 to 20 mph 


25 


55 to 20 mph 


250 


60 to 20 mph 



57.5 Service bral(e system— second effec- 
tiveness test. Repeat S7.3. Then (for passenger 
cars) [and other vehicles with a GVWR of 10,000 
lbs. or less) make four stops from 80 mph if the 
speed attainable in 2 miles is not less than 84 mph. 
(46 F.R. 55- January 2, 1981. Effective: 9/1/83)1 

57.6 First reburnish. Repeat ST. 4, except 
make 35 burnish stops or snubs. Reburnish a 
vehicle whose brakes are burnished according to 
S7.4.2.1 by making 35 snubs from 60 mph to 20 
mph, but if the hottest brake reaches 500° F ± 50° 
F make the remainder of the 35 applications from 
such initial speed divisible by five but less than 60 
mph as necessary to maintain a temperature of 
500°F±50°F. 

57.7 Parking brake test. The parking brake 
tests for any vehicle on different grades, in dif- 
ferent directions, and for different loads may be 
conducted in any order. The force required for ac- 
tuation of a hand-operated brake system shall be 
measured at the center of the hand grip area or at 
a distance of IV2 inches from the end of the actua- 
tion lever, as illustrated in Figure 2. 



R ■ 



-^—, t 



t" 



, H t^'" 



4 



T TYPE 




LEVER TYPE A 



F = APPIIED 
R = REACTION 



tOCATION fOR MEASURING BRAKE APPLICATION FORCE 
(HAND BRAKEI 



S7.4.2.2 Brake adjustment— post burnish. 

After burnishing, adjust the brakes manually in ac- 
cordance with the manufacturer's recommenda- 
tion if the brake systems are manual or if the 
automatic adjusters are locked out, or by making 
stops as recommended by the manufacturer if the 
automatic adjusters are operative. 

(Rev. 1/2/81) PART 571; S 105-11 



S7.7 Test procedure for requirements of S5.2.1. 

S7.7.1.1 Condition the parking brake friction 
elements so that the temperature at the beginning 
of the test is at any level not more than 150° F 



(when the temperature of components on both 
ends of an axle are averaged). 

S7.7.1.2 Drive the vehicle, loaded to GVWR, 
onto the specified grade with the longitudinal axis 
of the vehicle in the direction of the slope of the 
grade, stop the vehicle and hold it stationary by 
application of the service brake control, and place 
the transmission in neutral. 



S7.7.2 Test procedures for requirements of 
S5.2.2. (a) Check that transmission must be 
placed in park position to release key; 

(b) Test as in S7.7.1, except in addition place the 
transmission control to engage the parking 
mechanism; and 

(c) Test as in S7.7.1 except on a 20 percent 
grade, with the parking mechanism not engaged. 



57.7.1.3 With the vehicle held stationary by 
means of the service brake control, apply the park- 
ing brake by a single application of the force 
specified in (a) or (b), except that a series of ap- 
plications to achieve the specified force may be 
made in the case of a parking brake system design 
that does not allow the application of the specified 
force in a single application: 

1(a) In the case of a passenger car or other vehi- 
cle with a GVWR of 10,000 lbs. or less, not more 
than 125 pounds for a foot-operated system, and 
not more than 90 pounds for a hand-operated 
system; and 

(b) In the case of a school bus with a GVWR 
greater than 10,000 lbs. not more than 150 pounds 
for a foot-operated system, and not more than 125 
pounds for a hand-operated system. (46 F.R. 
55-January 2, 1981. Effective: 9/1/83)1 

57.7.1 .4 Following the application of the park- 
ing brake in accordance with S7.7.1.3, release all 
force on the service brake control and commence 
the measurement of time if the vehicle remains 
stationary. If the vehicle does not remain sta- 
tionary, reapplication of the service brake to hold 
the vehicle stationary, with reapplication of a force 
to the parking brake control at the level specified 
in S7.6. 1.3(a) or (b) as appropriate for the vehicle 
being tested (without release of the ratcheting or 
other holding mechanism of the parking brake) 
may be used twice to attain a stationary position. 

57.7.1 .5 Following observation of the vehicle in 
a stationary condition for the specified time in one 
direction, repeat the same test procedure with the 
vehicle orientation in the opposite direction on the 
specified grade. 

57.7.1.6 Check the operation of the parking 
brake application indicator required by S5.3.1(d). 



57.7.3 Lightly loaded vehicle. Repeat S7.7.1 or 
S7.7.2 as applicable except with the vehicle at 
lightly loaded vehicle weight. 

57.7.4 Non-service brake type parking brake 
systems. For vehicles with parking brake 
systems not utilizing the service brake friction 
elements, burnish the friction elements of such 
systems prior to parking brake tests according to 
the manufacturer's published recommendations as 
furnished to the purchaser. If no recommenda- 
tions are furnished, run the vehicle in an unbur- 
nished condition. 

57.8 Service brake system— lightly loaded 
vehicle (third effectiveness) test. Make six stops 
from 60 mph with vehicle at lightly loaded vehicle 
weight. [This test is not appHcable to a vehicle 
which both has a GVWR of not less than 8,000 
pounds and not greater than 10,000 pounds and is 
not a school bus. (46 F.R. 55-January 2, 1981. Ef 
fective: 9/1/83)1 

57.9 Service brake system test— partial failure. 

S7.9.1 With the vehicle at lightly loaded vehicle 
weight, alter the service brake system to produce 
any one rupture or leakage type of failure, other 
than a structural failure of a housing that is com- 
mon to two or more subsystems. Determine the 
control force, pressure level, or fluid level (as ap- 
propriate for the indicator being tested) necessary 
to activate the brake system indicator lamp. Make 
4 stops if the vehicle is equipped with a split service 
brake system, or 10 stops if the vehicle is not so 
equipped, each from 60 mph, by a continuous ap- 
plication of the service brake control. Restore the 
service brake system to normal at completion of 
this test. 



(Rev. 1/2/81) 



PART 571; S 105-12 



57.9.2 Repeat S7.9.1 for each of the other 
subsystems. 

57.9.3 Repeat S7.9.1 and S7.9.2 with vehicle 
at GVWR. Restore the service brake system to 
normal at completion of this test. 

57.9.4 (For vehicles with antilock and/or 
variable proportioning brake systems.) With 
vehicle at GVWR, disconnect functional power 
source, or otherwise render antilock system in- 
operative. Disconnect variable proportioning 
brake system. Make four stops, each from 60 
mph. If more than one antilock or variable 
proportioning brake subsystem is provided, dis- 
connect or render one subsystem inoperative and 
run as above. Restore system to normal at com- 
pletion of this test. Repeat for each subsystem 
provided. Determine whether the brake system 
indicator lamp is activated when the electrical 
power source to the antilock or variable propor- 
tioning unit is disconnected. 

S7.10 Service brake system— inoperative bralce 
power unit or brake power assist unit test. (For 
vehicles equipped with brake power unit or brake 
power assist unit.) 

57.10.1 Regular procedure. (This test need 
not be run if the option in S7.10.2 is selected.) 
On vehicles with brake power assist units, render 
the brake power assist unit inoperative, or one of 
the brake power assist unit subsystems if two or 
more subsystems are provided by disconnecting 
the relevant power supply. Exhaust any residual 
brake power reserve capability of the discon- 
nected system. On vehicles with brake power 
units, disconnect the primary source of power. 
Make four stops, each from 60 mph, by a con- 
tinuous application of the service brake control. 
Restore the system to normal at completion of 
this test. For vehicles equipped with more than 
one brake power unit or brake power assist unit, 
conduct tests for each in turn. 

57.10.2 Optionai procedures— passenger cars 
oniy. On vehicles with brake power assist units, 
the unit is charged to maximum prior to start of 



test. (Engine may be run up in speed, then 
throttle closed quickly to attain maximum charge 
on vacuum assist units.) Brake power units shall 
also be charged to maximum accumulator pres- 
sure prior to start of test. No recharging is 
allowed after start of test. 

(a) (For vehicles with brake power assist 
units.) 

Disconnect the primary source of power. Make 
six stops each from 60 mph, to achieve the aver- 
age deceleration for each stop as specified in 
Table III. Apply the brake control as quickly 
as possible. Maintain control force until vehicle 
has stopped. 

At the completion of the stops specified above, 
deplete the system of any residual brake power 
reserve capability. Make one stop from 60 mph 
at an average deceleration of not lower than 
7 fpsps for passenger cars (equivalent stopping 
distance 554 feet), or 6 fpsps for vehicles other 
than passenger cars (equivalent stoppng dis- 
tance 646 feet) and determine whether the con- 
trol force exceeds 150 pounds. 

(b) (For vehicles with brake power units 
with accumulator type systems.) Test as in 
S7. 10.2(a), except make 10 stops instead of 6 
and, at the completion of the 10 stops, deplete 
the failed element of the brake power unit of any 
residual brake power reserve capability before 
making the final stop. 

(c) (For vehicles with brake power assist or 
brake power units with backup systems.) If the 
brake power or brake power assist unit operates 
in conjunction with a backup system and the 
backup system is activated automatically in the 
event of a primary power failure, the backup 
system is operative during this test. Disconnect 
the primary source of power of one subsystem. 
Make 15 stops, each from 60 mph, with the 
backup system activated for the failed subsystem, 
to achieve an average deceleration of 12 fpsps 
for each stop. 

(d) Restore systems to normal at completion 
of these tests. For vehicles equipped with more 
than one brake power assist or brake power unit, 
conduct tests of each in turn. 



PART 571; S 105-13 



S7.11 Service brake system— first fade and re- 
covery test. 

57.11.1 Baseline checic stops or snubs. 

57.11.1.1 Vetiicles with GVWR of 10,000 pounds 
or less. Make three stops from 30 mph at 10 
fpsps for each stop. Control force readings may 
be terminated when vehicle speed falls to 5 mph. 
Average the maximum brake control force re- 
quired for the three stops. 

57.11.1.2 Vehicles with GVWR greater than 
10,000 pounds. With transmission in neutral (or 
declutched), make three snubs from 40 to 20 
mph at 10 fpsps for each snub. Average the 
maximum brake control force required for the 
three snubs. 

57.11.2 Fade stops or snubs. 

57.1 1.2.1 Vehicles with GVWR of 10,000 pounds 
or less. Make 5 stops from 60 mph at 15 fpsps 
followed by 5 stops at the maximum attainable 
deceleration between 5 and 15 fpsps for each 
stop. Establish an initial brake temperature 
before the first brake application of 130° F to 
150° F. Initial brake temperatures before 
brake applications for subsequent stops are 
those occurring at the distance intervals. Attain 
the required deceleration within 1 second and, as a 
minimum, maintain it for the remainder of the 
stopping time. Control force readings may be 
terminated when vehicle speed falls to 5 mph. 
Leave an interval of 0.4 mile between the start 
of brake applications. Accelerate immediately 
to the initial test speed after each stop. Drive 
1 mile at 30 mph after the last fade stop, and 
immediately follow the recovery procedure speci- 
fied in S7.11.3.1. 

57.1 1.2.2 Vehicles with GVWR greater than 
10,000 pounds. With transmission in neutral 
(or declutched), make 10 snubs from 40 to 20 
mph at 10 ^sps for each snub. Establish an 
initial brake temperature before the first brake 
application of 130° F to 150° F. Initial brake 
temperatures before brake application for subse- 
quent snubs are those occurring in the time in- 
tervals specified below. Attain the required 
deceleration within 1 second and maintain it for 
the remainder of the snubbing time. Leave an 



interval of 30 seconds between snubs (start of 
brake application to start of brake application). 
Accelerate immediately to the initial test speed 
after each snub. Drive for 1.5 miles at 40 mph 
after the last snub and immediately follow the 
recovery procedure specified in S7. 11.3.2. 

S7.11.3 Recovery stops or snubs. 

57.1 1.3.1 Vehicles with GVWR of 10,000 pounds 
or less. Make five stops from 30 mph at 10 
fpsps for each stop. Control force readings may 
be terminated when vehicle speed falls to 5 mph. 
Allow a braking distance interval of 1 mile. 
Immediately after each stop accelerate at maxi- 
mum rate to 30 mph and maintain that speed 
until making the next stop. Record the maxi- 
mum control force for each stop. 

57.1 1.3.2 Vehicles with GVWR greater than 
10,000 pounds. With transmission in neutral 
(or declutched), make five snubs from 40 to 20 
mph at 10 fpsps, for each snub. After each snub, 
accelerate at maximum rate to 40 mph and main- 
tain that speed until making the next brake 
application at a point 1.5 miles from the point 
of the previous brake application. Record the 
maximum control force for each snub. 

57.12 Service bralce system— second reburnish. 

Repeat S7.6. 

57.13 Service brake system-second fade and 
recovery test. Repeat S7.ll except in S7.11.2 run 
15 fade stops or 20 snubs instead of 10. 

57.14 Third reburnish. Repeat S7.6. 

57.15 Service brake system— fourth effective- 
ness test. Repeat S7.5. Then (for passenger 
cars) make four stops from either 95 mph if 
the speed attainable in 2 miles is 99 to (but not 
including) 104 mph, or 100 mph if the speed 
attainable in 2 miles is 104 mph or greater. 

57.16 Service brake system— water recovery 
test. 

S7.16.1 Baseline check stop. Make three stops 
from 30 mph at 10 fpsps for each stop. Control 
force readings may be terminated when vehicle 
speed falls to 5 mph. Average the maximum 
brake control force required for the three stops. 



PART 571; S 105-14 



S7.16.2 Wet brake recovery stops. With the 
brakes fully released at all times, drive the ve- 
hicle for 2 minutes at a speed of 5 mph, in any 
combination of forward and reverse directions, 
through a trough having a water depth of 6 
inches. After leaving the trough, immediately 
accelerate at maximum rate to 30 mph without a 
brake application. Immediately upon reaching 
that speed make five stops, each from 30 mph at 
10 fpsps for each stop. After each stop (except 
the last), accelerate the vehicle immediately at a 
maximum rate to a speed of 30 mph and begin 
the next stop. 

57.17 Spike stops. Make 10 successive spike 
stops from 30 mph with the transmission in 
neutral, with no reverse stops. Make spike stops 
by applying a control force of 200 pounds while 
recording control force versus time. Maintain 
control force until vehicle has stopped. At com- 
pletion of 10 spike stops, make 6 effectiveness 
stops from 60 mph. 

57.18 Final Inspection. Inspect— 

(a) The service brake system for detachment 
or fracture of any components, such as brake 
springs and brake shoes or disc pad facing. 

(b) The friction surface of the brake, the 
master cylinder or brake power unit reservoir 
cover, and seal and filler openings, for leakage 
of brake fluid or lubricant. 



(c) The master cylinder or brake power unit 
reservoir for compliance with the volume and 
labeling requirements of S5.4.2 and S5.4.3. In 
determining the fully applied worn condition 
assume that the lining is worn to (1) rivet or 
bolt heads on riveted or bolted linings or (2) 
within %2 inch of shoe or pad mounting surface 
or bonded linings, or (3) the limit recommended 
by the manufacturer, whichever is larger relative 
to the total possible shoe or pad movement. 
Drums or rotors are assumed to be at nominal 
design drum diameter or rotor thickness. Lin- 
ings are assumed adjusted for normal operating 
clearance in the released position. 

(d) The brake system indicator light(s), for 
compliance with operation in various key posi- 
tions, lens color, labeling, and location, in accord- 
ance with S5.3. 

S7.19 Moving barrier test. (Only for vehicles 
that have been tested according to S7.7.2.) Load 
the vehicle to GVWR, release parking brake and 
place the transmission selector control to engage 
the parking mechanism. With a moving barrier 
as described in paragraph 3.3 of SAE Recom- 
mended Practice J972 "Moving Barrier Collision 
Tests," November 1966, impact the vehicle from 
the front at 2V2 mph. Keep the longitudinal 
axis of the barrier parallel with the longitudinal 
axis of the vehicle. Repeat the test, impacting 
the vehicle from the rear. Note: The vehicle 
used for this test need not be the same vehicle 
that has been used for the braking tests. 



PART 571; S 105-15-16 



EffecHve: October 10, 1975 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 

Hydraulic Brake Systems 
(Docket No. 75-11; Notice 2) 



This notice amends Standard No. 105-75, 
Hydraulic Brake Systems, 49 CFR 571.105-75, 
to permit the manufacture of hydraulic-braked 
vehicles without split service brake systems as 
long as they are capable of meeting additional 
stopping requirements in the event of failure in 
the service brake system. A proposal of this 
modification was published May 12, 1975, (40 FR 
20641), in response to petitions from Citroen 
Automobile Company, Maserati, S.P.A., and 
Volkswagen of America, Inc. 

The three vehicle manufacturers requested 
modifications of Standard No. 105-75 (effective 
.January 1, 1976) because its present requirement 
for a split service brake system (S5.1) would 
prevent the development and sale of vehicles 
utilizing a central hydraulic system with a single 
pump. The split system has two or more sepa- 
rate subsystems, each operating indefinitely in 
the event of a failure in another subsystem, and 
is required as a safety measure to ensure that at 
least one-half of the braking system will remain 
operational if any single failure occurs. The 
central hydraulic system used by Citroen em- 
ploys a single pump to supply power to both 
front brakes and rear brakes. The petitions sug- 
gested and the NHTSA tentatively agreed that 
this type of central hydraulic system, which offers 
a limited number of stops upon a single failure, 
provides warning and reserve braking capabilities 
equivalent in safety to a split system. The peti- 
tioners asserted that the danger of operating in- 
definitely on one-half of a split system is as great 
as that of operating a central hydraulic system 
beyond its reserve capability. 

The responses to the proposal (including 
approximately 30 endorsements from owners of 
Citroen vehicles which employ the central hy- 



draulic system) generally supported the amend- 
ment to provide additional design flexibility in 
meeting Standard No. 105-75. Citroen, which 
intends to import passenger cars with central 
hydraulic systems, supported the proposal with 
one exception. The company pointed out that 
the special warning system specified in the pro- 
posal to accompany the central hydraulic system 
was technically unfeasible and conflicted with 
the existing requirements for warning systems 
in vehicles equipped with brake power units 
(S5.3.1). The same problem was raised by 
Clayton Dewandre Company Limited, a manu- 
facturer of brake systems for trucks, and Volks- 
wagen of America. Essentially, central hy- 
draulic systems are designed to operate within 
a pressure range, with intermittent pump opera- 
tion to restore the system accumulators to the 
higher pressure of the ranges as energy is used 
in braking or other hydraulic systems. A pres- 
sure sensor would be unable to distinguish the 
type of pressure drop experienced in this normal 
operation from that resulting from a rupture or 
leakage-type failure. Only after the pressure 
dropped below the pump "cut-in" pressure could 
the sensor experience an abnormal pressure level 
signifying system failure. 

The proposal, in contrast, would have required 
a warning as soon as any leakage or rupture 
occurs, before the abnormal pressure drop would 
be sensed. To revise the requirement in practical 
terms, the NHTSA amends the standard to 
eliminate the conflict between the proposed re- 
quirement and the existing requirement of 
S5.3.1(a)(4) for a warning when the supply 
pressure in a brake power unit drops to some 
level not less than one-half of the normal system 
pressure. 



PART 571; S 105-75— PRE 33 



Effective: October 10, 1975 

The amendment is placed in the same section 
of the standard as other requirements for warn- 
ing systems (S5.3) to improve the coherence of 
the entire standard and to clarify that the pres- 
sure warning required on central hydraulic sys- 
tems is not redundant or in conflict with the 
warnings called for in S5.3.1(a). 

For the same reason, the proposed requirement 
for additional stopping capability in central hy- 
draulic systems is placed in the same section as 
the requirement for partial failure system per- 
formance of split service brake systems (S5.1.2). 
Also, the partial failure test procedures for cen- 
tral hydraulic systems have been consolidated 
into the test procedures for split service brake 
systems in S7.9,l. 

Citroen, Volkswagen, and Clayton Dewandre 
stressed that the delay of warning signal neces- 
sitates a more fundamental modification of the 
proposed requirement for additional stopping 
capabilities. The proposal would have specified 
that the warning signal be activated as soon as 
the failure occurred, followed by a back-up ca- 
pability of 10 stops from 60 mph. Now that the 
signal has been specified as occurring somewhat 
after the failure (when abnormal pressure loss 
can be sensed), the 10-stop capability must be 
required subsequent to activation of the signal so 
that braking capability is available to the driver 
for a reasonable time after he has been warned 
that a malfunction has occurred. Citroen, the 
only manufacturer that expects to manufacture 
vehicles subject to these requirements at this time, 
states that its system is entirely capable of pro- 
viding 10-stops from 60 mph after the warning 
system activates. For this reason, the NHTSA 
considers it appropriate to amend the warning 
system requirement so that the 10-stop capability 
is available following activation of the signal. 

The NHTSA also proposed a clarification of 
the test procedures for brake power imit failure 
(S7.10.2(b)). No comments addressed this mat- 
ter, and the proposed change expanded slightly, 
is made final by this notice. 

Citroen suggested that a brake fluid level in- 
dicator be specified as an additional safety system 
on central hydraulic sj'stems, noting that such an 
indicator will become a requirement for vehicles 
with master cylinder reservoirs (as of September 



1, 1976). Wagner Electric Corporation recom- 
mended that a "system energy monitoring device" 
be specified so that volume as well as pressure 
would be monitored, arguing that a pressure in- 
dicator alone will not indicate a failure of the 
charging device in an accumulator. Clayton 
Dewandre suggested that if a split service brake 
system is no longer required, then the brake sys- 
tem should be better protected against failures 
of non-brake sj'stems (suspension, power steer- 
ing) that are connected to the brake system. 

The NHTSA considers each of these sugges- 
tions to have possible merit and contemplates a 
new proposal to treat these issues and provide 
for full opportunity for comment by interested 
persons. At this time, however, it is considered 
necessary to implement the amendments that will 
permit production of vehicles without split service 
brake systems under Standard No. 105-75. 

Both Wagner Electric and General Motors 
questioned the part of the preamble to the pro- 
posal that stated, "The [Citroen] response indi- 
cates that the Citroen system is not responsible 
for a greater percentage of accidents than a con- 
ventional system." Both companies felt that the 
submitted information did not form a statistically 
adequate basis for that conclusion. The NHTSA 
agrees. The statement in question was only in- 
tended to report Citroen's evaluation of the ma- 
terial it submitted in support of its petition, and 
not to present a conclusion of the NHTSA. 

In consideration of the foregoing, Standard 
No. 105-75 (49 CFR 571.105-75) is amended 

Effective date : October 10, 1975. Because these 
amendments have the effect of pennitting actions 
that previously were prohibited, it is found for 
good cause shown that an effective date sooner 
than 30 days following publication in the Federal 
Register is in the public interest. 

(Sec. 103, 119, Pub. L. 89-563, 80 Stat. 718 (15 
U.S.C. 1392, 1407) ; delegations of authority at 
49 CFR 1.51). 

Issued on Oct. 3, 1975. 

Gene G. Mannella 
Acting Administrator 

40 F.R. 47789 
October 10, 1975 



PART 571; S 105-75— PRE 34 



Effective: October 10, 1975 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 

Hydraulic Brake Systems 
(Docket No. 75-11; Notice 2) 



This notice amends Standard No. 105-75, 
Hydraulic Brake Systems, 49 CFR 571.105-75, 
to permit the manufacture of hydraulic-braked 
vehicles without split service brake systems as 
long as they are capable of meeting additional 
stopping requirements in the event of failure in 
the service brake system. A proposal of this 
modification was published May 12, 1975, (40 FR 
20641), in response to petitions from Citroen 
Automobile Company, Maserati, S.P.A., and 
Volkswagen of America, Inc. 

The three vehicle manufacturers requested 
modifications of Standard No. 105-75 (effective 
January 1, 1976) because its present requirement 
for a split service brake system (S5.1) would 
prevent the development and sale of vehicles 
utilizing a central hydraulic system with a single 
pump. The split system has two or more sepa- 
rate subsystems, each operating indefinitely in 
the event of a failure in another subsystem, and 
is required as a safety measure to ensure that at 
least one-half of the braking system will remain 
operational if any single failure occurs. The 
central hydraulic system used by Citroen em- 
ploys a single pump to supply power to both 
front brakes and rear brakes. The petitions sug- 
gested and the NHTSA tentatively agreed that 
this type of central hydraulic system, which offers 
a limited number of stops upon a single failure, 
provides warning and reserve braking capabilities 
equivalent in safety to a split system. The peti- 
tioners asserted that the danger of operating in- 
definitely on one-half of a split system is as great 
as that of operating a central hydraulic system 
beyond its reserve capability. 

The responses to the proposal (including 
approximately 30 endorsements from owners of 
Citroen vehicles which employ the central hy- 



draulic system) generally supported the amend- 
ment to provide additional design flexibility in 
meeting Standard No. 105-75. Citroen, which 
intends to import passenger cars with central 
hydraulic systems, supported the proposal with 
one exception. The company pointed out that 
the special warning system specified in the pro- 
posal to accompany the central hydraulic system 
was technically unfeasible and conflicted with 
the existing requirements for warning sj'stems 
in vehicles equipped with brake power units 
(S5.3.1). The same problem was raised by 
Clayton Dewandre Company Limited, a manu- 
facturer of brake systems for trucks, and Volks- 
wagen of America. Essentially, central hy- 
draulic systems are designed to operate within 
a pressure range, with intermittent pump opera- 
tion to restore the system accumulators to the 
higher pressure of the ranges as energy is used 
in braking or other hydraulic systems. A pres- 
sure sensor would be unable to distinguish the 
type of pressure drop experienced in this normal 
operation from that resulting from a rupture or 
leakage-type failure. Only after the pressure 
dropped below the pump "cut-in" pressure could 
tlie sensor experience an abnormal pressure level 
signifying system failure. 

The proposal, in contrast, would have required 
a warning as soon as any leakage or rupture 
occurs, before the abnormal pressure drop would 
be sensed. To revise the requirement in practical 
terms, the NHTSA amends the standard to 
eliminate the conflict between the proposed re- 
quirement and the existing requirement of 
S5.3.1 (a) (4) for a warning when the supply 
pressure in a brake power unit drops to some 
level not less than one-half of the normal system 
pressure. 



PART 571; S 105-75— PRE 33 



Effective: October 10, 1975 

The amendment is placed in the same section 
of the standard as other requirements for warn- 
ing systems (S5.3) to improve the coherence of 
the entire standard and to clarify that the pres- 
sure warning required on central hydraulic sj'S- 
tems is not redundant or in conflict with the 
warnings called for in S5.3.1(a). 

For the same reason, the proposed requirement 
for additional stopping capability in central hy- 
draulic systems is placed in the same section as 
the requirement for partial failure system per- 
formance of split service brake systems (S5.1.2). 
Also, the partial failure test procedures for cen- 
tral hydraulic systems have been consolidated 
into the test procedures for split service brake 
systems in S7.9.1. 

Citroen, Volkswagen, and Clayton Dewandre 
stressed that the delay of warning signal neces- 
sitates a more fundamental modification of the 
proposed requirement for additional stopping 
capabilities. The proposal would have specified 
that the warning signal be activated as soon as 
the failure occurred, followed by a back-up ca- 
pability of 10 stops from 60 mph. Now that the 
signal has been specified as occurring somewhat 
after the failure (when abnormal pressure loss 
can be sensed), the 10-stop capability must be 
required subsequent to activation of the signal so 
that braking capability is available to the driver 
for a reasonable time after he has been warned 
that a malfunction has occurred. Citroen, the 
only manufacturer that expects to manufacture 
vehicles subject to these requirements at this time, 
states that its system is entirely capable of pro- 
viding 10-stops from 60 mph after the warning 
system activates. For this reason, the NHTSA 
considers it appropriate to amend the warning 
system requirement so that the 10-stop capability 
is available following activation of the signal. 

The NHTSA also proposed a clarification of 
the test procedures for brake power unit failure 
(S7.10.2(b)). No comments addressed this mat- 
ter, and the proposed change expanded slightly, 
is made final by this notice. 

Citroen suggested that a brake fluid level in- 
dicator be specified as an additional safety system 
on central hydraulic systems, noting that such an 
indicator will become a requirement for vehicles 
with master cylinder reservoii-s (as of September 



1, 1976). Wagner Electric Corporation recom- 
mended that a "system energy monitoring device" 
be specified so that volume as well as pressure 
would be monitored, arguing that a pressure in- 
dicator alone will not indicate a failure of the 
charging device in an accumulator. Clayton 
Dewandre suggested that if a split service brake 
system is no longer required, then the brake sys- 
tem should be better protected against failures 
of non-brake s}'stems (suspension, power steer- 
ing) that are connected to the brake system. 

The NHTSA considers each of these sugges- 
tions to have possible merit and contemplates a 
new proposal to treat these issues and provide 
for full opportunity for comment by interested 
persons. At this time, however, it is considered 
necessary to implement the amendments that will 
permit production of vehicles without split service 
bi-ake systems under Standard No. 105-75. 

Both Wagner Electric and General Motors 
questioned the part of the preamble to the pro- 
posal that stated, "The [Citroen] response indi- 
cates that the Citroen system is not responsible 
for a greater percentage of accidents than a con- 
ventional system." Both companies felt that the 
submitted information did not form a statistically 
adequate basis for that conclusion. The NHTSA 
agrees. The statement in question was only in- 
tended to report Citroen's evaluation of the ma- 
terial it submitted in support of its petition, and 
not to present a conclusion of the NHTSA. 

In consideration of the foregoing. Standard 
No. 105-75 (49 CFR 571.105-75) is amended 

Effective date : October 10, 1975. Because these 
amendments have the effect of permitting actions 
that previously were prohibited, it is found for 
good cause shown that an effect i\'e date sooner 
than 30 days following publication in the Federal 
Register is in the public interest. 

(Sec. 103, 119, Pub. L. 89-563, 80 Stat. 718 (15 
U.S.C. 1392, 1407) ; delegations of authority at 
49 CFR 1.51). 

Issued on Oct. 3, 1975. 

Gene G. Mannella 
Acting Administrator 

40 F.R. 47789 
October 10, 1975 



PART 571; S 105-75— PRE 34 



Effective: January 6, 1976 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 

Hydraulic Brake Systems 
(Docket No. 75-27; Notice 2) 



This notice amends Standard No. 105-75, 
Hydraulic Brake Systems, 49 CFR 571.105-75, 
to revise the parking brake test procedure 
(S7.7). In addition, this notice amends Subpart 
B of Part 575, Consumer Information, 49 CFR 
§ 575.101, by replacing the present test proce- 
dures in that section for passenger car testing 
with equivalent procedures from Standard No. 
105-75. 

The NHTSA proposed a modification of the 
parking brake test procedures in Standard No. 
105-75 to permit a reapplication of the parking 
brake if the first application of the brake failed 
to hold the vehicle stationary on the test incline. 
Toyo Kogyo requested the modification as repre- 
sentative of normal driver action (in cases where 
the application appears to be insuflScient to hold 
the vehicle), justifying the change as necessary 
to permit new vehicle components to stretch or 
"set" during the initial application as occurs in 
any vehicle delivered to a purchaser. The 
NHTSA agreed that reapplication would be a 
reasonable test procedure and proposed a revi- 
sion of S7.7. 

Comments were received from Toj'o Kogyo, 
General Motors, American Motors Corporation, 
and Chrysler Corporation in support of the 
change. No comments were received that ob- 
jected to the proposal. The standard is amended 
accordingly. 

The NHTSA also proposed that the consumer 
information item requiring publication of the 
stopping ability of passenger cars and motor- 
cycles (49 CFR §757.101) be modified for pas- 
senger cars so that test data developed under 
Standard No. 105-75 could be the basis for the 
required consumer information. The existing 
test procedures of the consumer information item 



would be replaced by Standard No. 105-75 test 
procedures, and a transition period imtil Janu- 
ary 1, 1977, would be provided to allow manu- 
facturers latitude in adopting the new procedures. 

The Motor Vehicle Manufacturers Association 
(MVMA), Chrysler Corporation, American 
Motors Corporation, Ford Motor Company, and 
General Motors Corporation supported the modi- 
fications. The M^-'MA and Ford pointed out an 
inadvertent omission in the proposal of a re- 
quired change in the present loading specification 
(maximum loaded vehicle weight) to the Stand- 
ard No. 105-75 loading specification (gross 
vehicle weight rating (GV^VR)). No comments 
opposed the modification, and the consumer in- 
formation item is therefore amended as proposed, 
with the additional modification noted by the 
MVMA and Ford. The transition period for 
use of either loading specification conforms to 
the transition period for use of either test pro- 
cedure (until January 1, 1977). The MVMA 
asked for a June 1, 1977, date for transition to 
the new loading specification but did not explain 
the need for more time. The NHTSA will con- 
sider any data on this subject submitted by the 
MVMA. 

With regard to test loading, Chrysler Cor- 
poration repeated a request for revision of the 
loading conditions of Standard No. 105-75. The 
request was earlier submitted improperly as a 
petition for reconsideration of an NHTSA action 
which did not deal with test loading (40 FR 
24525, June 9, 1975). Section 553.35 of NHTSA 
regulations (49 CFR 553.35) allows petitions 
for reconsideration of rules issued by the 
NHTSA, but in this case no rule was issued on 
test loading that could form the basis for recon- 
sideration. The NHTSA discussed Chrysler's 



PART 571; S 105-75— PRE 35 



Effective: January 6, 1976 



request at a meeting with Chrysler officials on 
August 21, 1975. Based on the limited infor- 
mation presented by Chrysler at that meeting, 
the NHTSA has concluded that a reduction in 
test weight would not be justified. At the meet- 
ing it was agreed that Chrysler would sub:nit 
any additional data it had in support of the re- 
quest. To date no data have been received, and 
the NHTSA cannot meaningfully reconsider 
Chrysler's request without further data. 

The NHTSA also proposed modification of 
the means for establishing the skid number of 
the surface on which stopping distance tests are 
conducted in Standard No. 105-75, Standard No. 
121, Air Brake Systems, Standard No. 122, Motor- 
cycle Brake System, and the Consumer Infor- 
mation Item on brake performance. Comments 
received were not in agreement on how to accom- 
plish the transition from the former ASTM 
method to the new one. The skid number pro- 
posal will therefore be treated separately at a 
later date so that its resolution will not delay 



this amendment of the parking brake and con- 
sumer information item test procedures. 

In consideration of the foregoing, amendments 
are made in Chapter V of Title 49, Code of 
Federal Regulations. . . . 

Effective date : January 6, 1976. Because these 
amendments, to the extent that they impose new 
substantive requirements, are made optional for 
an interim period, and because manufacturers 
must plan future testing based on the test pro- 
cedures as they exist in the present standard, 
it is foimd for good cause shown that an im- 
mediate effective dat« is in the public interest. 

(Sec. 103, 119 Pub. L. 89-563, 80 Stat. 718 (15 
U.S.C. 1392, 1407) ; delegation of authority at 
49 CFR 1.51). 

Issued on December 31, 1975. 

James B. Gregory 
Administrator 
41 F.R. 1066 
January 6, 1976 



PART 571; S 105-75— PRE 36 



Effective: January 6, 1976 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 

Hydraulic Brake Systems 
(Docket No. 75-27; Notice 2) 



This notice amends Standard No. 105-75, 
Hydraulic Brake Systems, 49 CFR 571.105-75, 
to revise the parking brake test procedure 
(S7.7). In addition, this notice amends Subpart 
B of Part 575, Consumer Information, 49 CFR 
§ 575.101, by replacing the present test proce- 
dures in that section for passenger car testing 
with equivalent procedures from Standard No. 
105-75. 

The NHTSA proposed a modification of the 
parking brake test procedures in Standard No. 
105-75 to permit a reapplication of the parking 
brake if the first application of the brake failed 
to hold the vehicle stationary on the test incline. 
Toyo Kogyo requested the modification as repre- 
sentative of normal driver action (in cases where 
the application appears to be insuflScient to hold 
the vehicle), justifying the change as necessary 
to permit new vehicle components to stretch or 
"set" during the initial application as occurs in 
any vehicle delivered to a purchaser. The 
NHTSA agreed that reapplication would be a 
reasonable test procedure and proposed a revi- 
sion of S7.7. 

Comments were received from Toyo Kogyo, 
General Motors, American Motors Corporation, 
and Chrysler Corporation in support of the 
change. No comments were received that ob- 
jected to the proposal. The standard is amended 
accordingly. 

The NHTSA also proposed that the consumer 
information item requiring publication of the 
stopping ability of passenger cars and motor- 
cycles (49 CFR §757.101) be modified for pas- 
senger cars so that test data developed under 
Standard No. 105-75 could be the basis for the 
required consumer information. The existing 
test procedures of the consumer information item 



would be replaced by Standard No. 105-75 test 
procedures, and a transition period until Janu- 
ary 1, 1977, would be provided to allow manu- 
facturers latitude in adopting the new procedures. 

The Motor Vehicle Manufacturers Association 
(MVMA), Chrysler Corporation, American 
Motors Corporation, Ford Motor Company, and 
General Motors Corporation supported the modi- 
fications. The MVMA and Ford pointed out an 
inadvertent omission in the proposal of a re- 
quired change in the present loading specification 
(maximum loaded vehicle weight) to the Stand- 
ard No. 105-75 loading specification (gross 
vehicle weight rating (GV\VR)). No comments 
opposed the modification, and the consumer in- 
formation item is therefore amended as proposed, 
with the additional modification noted by the 
MVMA and Ford. The transition period for 
use of either loading specification conforms to 
the transition period for use of either test pro- 
cedure (until January 1, 1977). The MVMA 
asked for a June 1, 1977, date for transition to 
the new loading specification but did not explain 
the need for more time. The NHTSA will con- 
sider any data on this subject submitted by the 
MVMA. 

With regard to test loading, Chrysler Cor- 
poration repeated a request for revision of the 
loading conditions of Standard No. 105-75. The 
request was earlier submitted improperly as a 
petition for reconsideration of an NHTSA action 
which did not deal with test loading (40 FR 
24525, June 9, 1975). Section 553.35 of NHTSA 
regulations (49 CFR 553.35) allows petitions 
for reconsideration of rules issued by the 
NHTSA, but in this case no rule was issued on 
test loading that could form the basis for recon- 
sideration. The NHTSA discussed Chrysler's 



PART 571; S 105-75— PRE 35 



EffacMv*: January 6, 1976 

request at a meeting with Chrysler officials on 
August 21, 1975. Based on the limited infor- 
mation presented by Chrysler at that meeting, 
the NHTSA has concluded that a reduction in 
test weight would not be justified. At the meet- 
ing it was agreed that Chrysler would submit 
any additional data it had in support of the re- 
quest. To date no data have been received, and 
the NHTSA cannot meaningfully reconsider 
Chrysler's request without further data. 

The NHTSA also proposed modification of 
the means for establishing the skid number of 
the surface on which stopping distance tests are 
conducted in Standard No. 105-75, Standard No. 
121, Air Brake Systems, Standard No. 122, Motor- 
cycle Brake System, and the Consumer Infor- 
mation Item on brake performance. Comments 
received were not in agreement on how to accom- 
plish the transition from the former ASTM 
method to the new one. The skid number pro- 
posal will therefore be treated separately at a 
later date so that its resolution will not delay 



this amendment of the parking brake and con- 
sumer information item test procedures. 

In consideration of the foregoing, amendments 
are made in Chapter V of Title 49, Code of 
Federal Regulations. . . . 

Effective date : January 6, 1976. Because these 
amendments, to the extent that they impose new 
substantive requirements, are made optional for 
an interim period, and because manufacturers 
must plan future testing based on the test pro- 
cedures as they exist in the present standard, 
it is found for good cause shown that an im- 
mediate effective date is in the public interest. 

(Sec. 103, 119 Pub. L. 89-563, 80 Stat. 718 (15 
U.S.C. 1392, 1407); delegation of authority at 
49 CFR 1.51). 

Issued on December 31, 1975. 

James B. Gregory 
Administrator 
41 F.R. 1066 
January 6, 1976 



PART 571; S 105-75— PRE 36 



Eftactive: Octobar 12, 1976 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 

Hydraulic Brake Systems 
(Docket No. 75-7; Notice 2) 



This notice amends Standard No. 105-75, 
Hydraulic Brake Systems, 49 CFE 571.105-75, to 
extend its applicability to school buses and to 
establish performance levels for this vehicle cate- 
gory. 

The NHTSA proposed applicability of the 
hydraulic brake standard to school buses (40 FR 
18469, April 28, 1975) in satisfaction of the man- 
date of the Motor Vehicle and Schoolbus Safety 
Amendments of 1974 (Pub. L. 93-492) to issue 
safety standards for school bus operating sys- 
tems (15 U.S.C. §1392(i)(l)(A)). The Act 
established a strict schedule for promulgation 
of the standards, requiring their effectiveness 9 
months following promulgation. With a view 
to this limited leadtime, the NHTSA proposed 
performance levels based on Society of Auto- 
motive Engineers (SAE) recommended practices 
that reflect the better existing school bus designs. 
Permissible pedal force values and fade and re- 
covery performance were proposed at somewhat 
more stringent levels than the SAE practice, in 
view of the "stop-and-go" duty cycle of school 
buses, and the high incidence of women as school 
bus operators. 

Commenters generally supported extension of 
the hydraulic brake standard to school buses. 
The American Mutual Insurance Alliance sup- 
ported the standard as proposed. The California 
Highway Safety Foundation and Action for 
Child Transportation Safety (ACTS) advocated 
early implementation of requirements for all 
hydraulic-braked trucks, buses and multipurpose 
passenger vehicles to improve their braking com- 
patibility with school buses and passenger cars. 
The California Department of Highway Patrol 
(CHP) expressed concern that any bus could 



be converted into a school bus after sale, and 
that all buses should therefore be required to 
meet minimum braking requirements. The 
NHTSA is presently preparing rulemaking for 
hydraulic-braked trucks, buses, and MPV's, and 
these comments are being taken into considera- 
tion. In view of the Congressional mandate for 
swift implementation of school bus standards, 
however, this rulemaking is being made final 
largely as it was proposed. 

The NHTSA proposed a level of service brake 
system performance generally based on SAE 
values, both for school buses of 10,000 pounds 
gross vehicle weight rating (GVWR) or less, and 
for school buses with a GVWR or more than 
10,000 pounds. Wagner Electric Corporation, 
Chrysler Corporation, International Harvester 
Co., and Ford Motor Company asked for relaxa- 
tion of the requirements, while the Vehicle 
Equipment Safety Commission (VESC) and 
ACTS requested more stringent requirements. 
General Motors supported the requirements for 
buses with a GVWR of 10,000 pounds or less. 

The first effectiveness test (S5.1.1.1) measures 
the stopping ability of the service brake system 
as it is delivered to the user before it has been 
burnished (broken in) through use. Wagner 
argued that this test is unnecessary and there- 
fore wasteful because the stringency of later tests 
assures the adequacy of the "green" braking com- 
ponents to stop the vehicle. The company cited 
variables in the unconditioned components that 
make it ". . . imrealistic to assume that exact 
brake performance can be predicted or that test 
results can be repeated without the thermal and 
mechanical conditioning of these surfaces." 



PART 571: S 105-75— PRE 37 



Effective: October 12, 1976 



It is the NHTSA's intent in the first effective- 
ness test to assure a safe vehicle in the hands 
of the user from the moment of delivery. The 
same variables cited by Wagner that make pre- 
diction of test results difficult could also make 
performance in the hands of the user unpre- 
dictable, imless the design is carefully controlled. 
The NHTSA concludes that the first effective- 
ness requirement is a reasonable method of ensur- 
ing adequate new-vehicle performance, and denies 
Wagner's request to delete this requirement. 

Chrysler and Ford recommended increasing 
the first effectiveness stopping distances at 30 
mph for school buses with a GVWR of 10,000 
pounds or less. Both argued that vehicles take 
significantly longer to stop in an unbumished 
condition and therefore the required stopping 
distance for first effectiveness should be longer 
than the second effectiveness requirement. The 
NHTSA established the imbumished stopping 
distance requirements based on tests of vehicles 
by NHTSA contractors and its Safety Research 
Laboratory. The NHTSA has reexamined its 
test results in view of manufacturer comments, 
and has determined that the complying distances 
recorded were not generated in all cases at the 
"worst case" weight at which a vehicle could 
be tested. For this reason, and because of the 
variability noted above, the NHTSA has in- 
creased the first effectiveness stopping distances 
for school buses of 10,000 pounds GVWR or less 
to 69 feet. This change represents a 1 fpsps 
decrease in average deceleration rate from the 
second effectiveness value, as is the case for pas- 
senger cars. 

In the case of vehicles with a GVWR of more 
than 10,000 pounds, Wagner, Chrysler, and 
International Harvester requested longer stop- 
ping distances at 30 mph. The VESC and ACTS 
requested the same stopping distances for heavy 
school buses as for lighter ones. The NHTSA 
proposed more stringent low-speed stopping re- 
quirements than the SAE values to remain con- 
sistent with existing requirements of the National 
Conference on School Transportation, the State 
of California, and the Bureau of Motor Carrier 
Safety. International Harvester pointed out 
that, while the distances are comparable, the re- 
quirements are in fact more stringent because of 



the "no lockup" requirement and the limits on 
pedal control force in Standard No. 105-75. In 
view of these variations from existing 30-mph 
stopping distance requirements, and the less effec- 
tive braking encountered prior to burnish, the 
first effectiveness stopping distance at 30 mph 
is increased from 81 feet to 88 feet. In terms 
of deceleration rate, this 7-foot increase is com- 
parable to the 4- foot increase for light school 
buses. Stopping distance requirements other 
than 30-mph first effectiveness values are adopted 
as proposed. 

The second effectiveness test (S5.1.1.2) is of 
the service brake system following burnish of 
the brakes and with the vehicles loaded to its 
GVWR. Comments were received from Wagner 
and International Harvester on the distance 
established for 30-mph stops, and from the 
VESC and ACTS on the full range of stopping 
distance requirements, for both light and heavy 
school buses. International made the same point 
that it made for other stopping distance tests: 
that the low-speed distances chosen as comparable 
to existing requirements are somewhat more dif- 
ficult due to Standard No. 105-75's specification 
of "no lockup" and pedal control force limits. 
In this case, however, the value chosen is far less 
demanding than that for the unburnished brakes, 
and the factors cited by International are not as 
crucial. 

Wagner assumed that the NHTSA, in adopt- 
ing existing school bus "equivalent distance" 
performance requirements for actual road tests, 
had not compensated for the fact that existing 
standards refer to deceleration rates measured 
by inertial decelerometers. Actually, the NHTSA 
did apply correction factors to compensate for 
this fact. Wagner's request for longer distances 
is denied for this reason. 

ACTS asked that the NHTSA set perform- 
ance requirements equal to those for other ve- 
hicles that share the highway with school buses. 
The VESC recommended decreased stopping 
distances roughly comparable to values for trucks 
and buses in Standard No. 105-75 before the 
standard was indefinitely delayed (40 FR 18411, 
April 28, 1975). For reasons established in the 
preamble to that decision, the NHTSA is con- 
sidering appropriate interim performance levels 



PART 571; S 105-75— PRE 38 



Effective: October 12, 1976 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 

Hydraulic Brake Systems 
(Docket No. 75-7; Notice 2) 



This notice amends Standard No. 105-75, 
Hydraulic Brake Systems, 49 CFR 571.105-75, to 
extend its applicability to school buses and to 
establish performance levels for this vehicle cate- 
gory. 

The NHTSA proposed applicability of the 
hydraulic brake standard to school buses (40 FR 
18469, April 28, 1975) in satisfaction of the man- 
date of the Motor Vehicle and Schoolbus Safety 
Amendments of 1974 (Pub. L. 93-492) to issue 
safety standards for school bus operating sys- 
tems (15 U.S.C. §1392(i)(l)(A)). The Act 
established a strict schedule for promulgation 
of the standards, requiring their effectiveness 9 
months following promulgation. With a view 
to this limited leadtime, the NHTSA proposed 
performance levels based on Society of Auto- 
motive Engineers (SAE) recommended practices 
that reflect the better existing school bus designs. 
Permissible pedal force values and fade and re- 
covery performance were proposed at somewhat 
more stringent levels than the SAE practice, in 
view of the "stop-and-go" duty cycle of school 
buses, and the high incidence of women as school 
bus operators. 

Commenters generally supported extension of 
the hydraulic brake standard to school buses. 
The American Mutual Insurance Alliance sup- 
ported the standard as proposed. The California 
Highway Safety Foundation and Action for 
Child Transportation Safety (ACTS) advocated 
early implementation of requirements for all 
hydraulic-braked trucks, buses and multipurpose 
passenger vehicles to improve their braking com- 
patibility with school buses and passenger cars. 
The California Department of Highway Patrol 
(CHP) expressed concern that any bus could 



be converted into a school bus after sale, and 
that all buses should therefore be required to 
meet minimum braking requirements. The 
NHTSA is presently preparing rulemaking for 
hydraulic-braked trucks, buses, and MPV's, and 
these comments are being taken into considera- 
tion. In view of the Congressional mandate for 
swift implementation of school bus standards, 
however, this rulemaking is being made final 
largely as it was proposed. 

The NHTSA proposed a level of service brake 
system performance generally based on SAE 
values, both for school buses of 10,000 pounds 
gross vehicle weight rating (GVVVK) or less, and 
for school buses with a GVWR or more than 
10,000 pounds. Wagner Electric Corporation, 
Chrysler Corporation, International Harvester 
Co., and Ford Motor Company asked for relaxa- 
tion of the requirements, while the Vehicle 
Equipment Safety Commission (VESC) and 
ACTS requested more stringent requirements. 
General Motors supported the requirements for 
buses with a GVWR of 10,000 pounds or less. 

The first effectiveness test (S5.1.1.1) measures 
the stopping ability of the service brake system 
as it is delivered to the user before it has been 
burnished (broken in) through use. Wagner 
argued that this test is unnecessary and there- 
fore wasteful because the stringency of later tests 
assures the adequacy of the "green" braking com- 
ponents to stop the vehicle. The company cited 
variables in the unconditioned components that 
make it ". . . unrealistic to assume that exact 
brake performance can be predicted or that test 
results can be repeated without the thermal and 
mechanical conditioning of these surfaces." 



PART 571; S 105-75— PRE 37 



EffecHve: Oclobor 12, 1976 



It is the NHTSA's intent in the first effective- 
ness test to assure a safe vehicle in the hands 
of the user from the moment of delivery. The 
same variables cited by Wagner that make pre- 
diction of test results difficult could also make 
performance in the hands of the user unpre- 
dictable, unless the design is carefully controlled. 
The NHTSA concludes that the first effective- 
ness requirement is a reasonable method of ensur- 
ing adequate new-vehicle performance, and denies 
Wagner's request to delete this requirement. 

Chrysler and Ford recommended increasing 
the first effectiveness stopping distances at 30 
mph for school buses with a GVWE of 10,000 
pounds or less. Both argued that veliicles take 
significantly longer to stop in an imbumished 
condition and therefore the required stopping 
distance for first effectiveness should be longer 
than the second effectiveness requirement. The 
NHTSA established the unbumished stopping 
distance requirements based on tests of vehicles 
by NHTSA contractors and its Safety Research 
Laboratory. The NHTSA has reexamined its 
test results in view of manufacturer comments, 
and has determined that the complying distances 
recorded were not generated in all cases at the 
"worst case" weight at which a vehicle could 
be tested. For this reason, and because of the 
variability noted above, the NHTSA has in- 
creased the first effectiveness stopping distances 
for school buses of 10,000 pounds GVWE or less 
to 69 feet. This change represents a 1 fpsps 
decrease in average deceleration rate from the 
second effectiveness value, as is the case for pas- 
senger cars. 

In the case of vehicles with a GVWE of more 
than 10,000 pounds, Wagner, Chrysler, and 
International Harvester requested longer stop- 
ping distances at 30 mph. The VESC and ACTS 
requested the same stopping distances for heavy 
school buses as for lighter ones. The NHTSA 
proposed more stringent low-speed stopping re- 
quirements than the SAE values to remain con- 
sistent with existing requirements of the National 
Conference on School Transportation, the State 
of California, and the Bureau of Motor Carrier 
Safety. International Harvester pointed out 
that, while the distances are comparable, the re- 
quirements are in fact more stringent because of 



the "no lockup" requirement and the limits on 
pedal control force in Standard No. 105-75. In 
view of these variations from existing 30-mph 
stopping distance requirements, and the less effec- 
tive braking encountered prior to burnish, the 
first effectiveness stopping distance at 30 mph 
is increased from 81 feet to 88 feet. In terms 
of deceleration rate, this 7-foot increase is com- 
parable to the 4-foot increase for light school 
buses. Stopping distance requirements other 
than 30-mph first effectiveness values are adopted 
as proposed. 

The second effectiveness test (S5.1.1.2) is of 
the service brake system following burnish of 
the brakes and with the vehicles loaded to its 
GVWE. Comments were received from Wagner 
and International Harvester on the distance 
established for 30-mph stops, and from the 
VESC and ACTS on the full range of stopping 
distance requirements, for both light and heavy 
school buses. International made the same point 
that it made for other stopping distance tests: 
that the low-speed distances chosen as comparable 
to existing requirements are somewhat more dif- 
ficult due to Standard No. 105-75's specification 
of "no lockup" and pedal control force limits. 
In this case, however, the value chosen is far less 
demanding than that for the unburnished brakes, 
and the factors cited by International are not as 
crucial. 

Wagner assumed that the NHTSA, in adopt- 
ing existing school bus "equivalent distance" 
performance requirements for actual road tests, 
had not compensated for the fact that existing 
standards refer to deceleration rates measured 
by inertial decelerometers. Actually, the NHTSA 
did apply correction factors to compensate for 
this fact. Wagner's request for longer distances 
is denied for this reason. 

ACTS asked that the NHTSA set perform- 
ance requirements equal to those for other ve- 
hicles that share the highway with school buses. 
The VESC recommended decreased stopping 
distances roughly comparable to values for trucks 
and buses in Standard No. 105-75 before the 
standard was indefinitely delayed (40 FE 18411, 
April 28, 1975). For reasons established in the 
preamble to that decision, the NHTSA is con- 
sidering appropriate interim performance levels 



PART 571; S 105-75— PEE 38 



Effective: October 12, 1976 



for hydraulic-braked vehicles other than passen- 
ger cars, but is not prepared to specify perform- 
ance levels at this time. The ACTS and VESC 
requests will be considered as they apply to those 
interim requirements, but cannot be considered 
in this rulemaking because they would neces- 
sitate hardware changes that cannot be effec- 
tuated prior to the October 27, 1976, statutory 
deadline for effectiveness of this standard. 

The NHTSA proposed that second effective- 
ness performance requirements at speeds in excess 
of 60 mph not be specified for school buses. The 
VESC has argued that such requirements should 
apply to school buses if they have such high 
speed capability. While the NHTSA cannot 
promulgate requirements in this area in the short 
period that remains prior to the standard's man- 
dated effectiveness, the VESC position will be 
considered in developing future standards for all 
vehicles other than passenger cars, including 
school buses. In view of the above, the second 
effectiveness distances are adopted as proposed. 

No comment was received on the requirements 
for lightly-loaded stopping distances (S5.1.1.3) 
other than those already discussed with regard 
to the second effectiveness test, and the proposed 
values are therefore also adopted. The second 
sentence of S5.1.1.3 (referring to vehicles to 
which the standard is no longer applicable) is 
also deleted as proposed. 

The fourth effectiveness test (S5.1.1.4) is of 
the abilities of the brake system after it lias been 
subjected to fade and recovery testing under 
S5.1.4. Manufacturer comments indicated that, 
in the case of school buses with a GVWR greater 
than 10,000 pounds, use of a "hot" burnish pro- 
cedure (S7.4.2.1.2) in combination with the 
standard's fade and recovery testing makes the 
fourth effectiveness test redundant. NHTSA 
analysis agrees with these arguments, and in view 
of the fact that the hot burnish option will be- 
come the only permissible method of conditioning 
the brakes after September 1, 1976, the proposed 
fourth effectiveness test for heavier school buses 
is not adopted. 

Since use of the hot burnish procedure was 
an important factor in the decision to drop the 
fourth effectiveness requirement for vehicles over 
10,000 pounds GVWE, the NHTSA denies the 



Wagner petition to extend the alternative burnish 
procedures under S7.4.2.1 after the scheduled 
deletion of that option on September 1, 1976. 
Because this option ends before the standard's 
effectiveness for school buses, S7.4.2.1 has been 
simplified by eliminating the cold burnish pro- 
cedure, (S7.4.2.1.1) that will not be used. 

The NHTSA also notes General Motors' argu- 
ment that the fourth effectiveness test should be 
eliminated for vehicle classes offered with either 
hydraulic or air brakes simply because there is 
no comparable requirement in Standard No. 121, 
Air Brake Systems. ^Vhile the NHTSA agrees 
that vehicle classes ideally might be subjected 
to identical requirements whatever the method 
of brake actuation, formulation of any desired 
compatibility between hydraulic and air-braked 
vehicles of the same weight class must be accom- 
plished separately from this rulemaking on 
school buses, which is subject to a statutory dead- 
line. General ilotors' view will be considered 
in future rulemaking. 

The April 28 notice proposed deletion, for 
school buses, of the option methods for testing 
the service brake system in the event the brake 
power assist or brake power unit failed (S5.1.3). 
The only comment received was from the VESC, 
which misunderstood the proposal as deleting all 
tests of a failed power assist or power unit. In 
fact, school buses will be required to meet 
S5.1.3.1 as hereby amended. The VESC mis- 
understanding may have arisen because of un- 
clear language used in proposing an amendment 
of the test procedure of S7.10 that underlies the 
requirement. Section S7.10 is appropriately re- 
\4sed in this amendment of the standard. 

The NHTSA proposed more stringent fade 
and recovery performance for school buses than 
the SAE's recommended levels for other truck- 
type veliicles, because of the distinctive school 
bus duty cycle. School buses make a high num- 
ber of stops compared to the truck-type vehicles 
which may share common components. These 
stops are usually made on secondary roads that 
often have steeper grades than the primary road 
system. The National School Transportation 
Association (NSTA) confirmed in statements 
before an NHTSA public meeting on hydraulic 
brakes that the association's experience indicated 



PART 571; S 105-75— PEE 39 



EffecHve: October 12, 1976 



inadequate fade resistance in some of today's 
school buses. Wliile NHTSA testing indicates 
that some buses already conform to this require- 
ment, other buses will be required to upgrade 
their brake systems to confonn to this minimum 
performance level. 

Three manufacturers objected to this perform- 
ance level and each suggested a different modifi- 
cation of the proposed requirement to reduce its 
stringency. Ford requested a 200-pound allow- 
able pedal force for the first five stops, stating 
that "The 60 mph fade sequence represents, in 
Ford's opinion, an extreme condition that would 
rarely, if ever, be duplicated in normal customer 
operation of school buses." Wagner stated "It 
is inconsistent to require one degree of vehicle 
braking for the Effectiveness Test and another 
(in this case, more powerful) for the Fade and 
Recovery. . . . We agree in the need for some 
measure of fade and recovery but the redundancy 
of two such requirements in a minimum standard 
has not been addressed. . . ." General Motors 
cited the good safety record of school buses, ques- 
tioned the adequacy of NHTSA testing, and 
stated, with regard to school buses with a GVWR 
of more than 10,000 pounds, ". . . . the NHTSA 
has proposed stringent fade and recovery require- 
ments which far exceed minimum performance 
requirements." 

"Minimum" performance standards do not 
equate with "minimal" performance standards, 
as implied by General Motors and Wagner. The 
word "minimum" in the statutory definition of 
motor vehicle safety standards (15 U.S.C. § 1391- 
(2)), does not refer to the substantive content of 
the standards but rather to their legal status — 
that the products covered must not fall short of 
them. 

Wagner considered it inconsistent to specify a 
performance level for the fade characteristics of 
a braking system that would have the effect of 
improving another characteristic of the braking 
system (stopping distance performance) beyond 
the minimum level specified in tlie standard. Tlie 
NHTSA disagrees, and considers it appropriate 
to specify the minimum fade perfoi-mance neces- 
sary to assure adequate performance of brakes 
in stop-and-go operation, whether or not satis- 
faction of this minimum level results in a brake 



system with better stopping distance performance 
tlian required by the standard. 

While Ford is correct that the test sequence 
typically will not be experienced in day-to-day 
operations, that does not rule out the need for 
the improved fade characteristics suggested by 
the NSTA. Each of the commenters claims that 
the fade and recovery characteristics do exceed 
the poorest performance of some existing vehicles, 
but none presented convincing justification for 
their positions that the proposed levels are in- 
appropriate for school bus braking systems. It 
is also noted that school buses with a GVWR 
of more than 10,000 pounds no longer have to 
meet the high-speed or fourth effectiveness re- 
quirements. With regard to Ford's suggestion 
of permitting a 200-pound pedal control force, 
the NHTSA continues to consider a 150-pound 
maximum necessary in view of the large per- 
centage of school bus operators that are women 
(see HSRI Report No. HuF-6, NBS Technical 
Note 557, October 1970, "The Brake Pedal Force 
Capability of Adult Females"). Accordingly, 
the fade and recovery performance values are 
promulgated as proposed. The proposed word- 
ing of S5.1.4.3(b) (2) is modified for clarity in 
response to Wagner's request. 

The proposal included a minimum performance 
level for the ability of school bus brakes to per- 
form after they are soaked with water. Three 
comments were received that objected to the pro- 
posed performance levels. Wagner also objected 
that the test conditions were stated with insuf- 
ficient specificity. The width of the water trough 
used to wet the brakes is not specified and the 
width may affect the degree of wetting achieved 
in large truck tire sizes. The NHTSA intends 
to address this issue in its upcoming proposal on 
test intervals in the water recovery test. 

For the present NHTSA will resolve differ- 
ences in this test condition in the manufacturer's 
favor if they affect the outcome of testing. 

General Motoi-s' only objection to inclusion of 
a water recovery test in this standard for school 
buses over 10,000 pounds GVWR was that a 
comparable test in Standard No. 121 has not been 
developed. The NHTSA is not, of course, limited 
in the breadth of one standard by the breadth 
of another, whether or not they measure the same 
aspect of performance of a vehicle. 



PART 571; S 105-75— PRE 40 



Effective: October 12, 1976 



for hydraulic-braked vehicles other than passen- 
ger cars, but is not prepared to specify perform- 
ance levels at this time. The ACTS and VESC 
requests will be considered as they apply to those 
interim requirements, but cannot be considered 
in this rulemaking because they would neces- 
sitate hardware changes that cannot be effec- 
tuated prior to the October 27, 1976, statutory 
deadline for effectiveness of this standard. 

The NHTSA proposed that second effective- 
ness performance requirements at speeds in excess 
of 60 mph not be specified for school buses. The 
VESC has argued that such requirements should 
apply to school buses if they have such high 
speed capability. While the NHTSA cannot 
promulgate requirements in this area in the short 
period that remains prior to the standard's man- 
dated effectiveness, the VESC position will be 
considered in developing future standards for all 
vehicles other than passenger cars, including 
school buses. In view of the above, the second 
effectiveness distances are adopted as proposed. 

No comment was received on the requirements 
for lightly-loaded stopping distances (S5.1.1.3) 
other than those already discussed with regard 
to the second effectiveness test, and the proposed 
values are therefore also adopted. The second 
sentence of S5.1.1.3 (referring to vehicles to 
which the standard is no longer applicable) is 
also deleted as proposed. 

The fourth effectiveness test (S5.1.1.4) is of 
the abilities of the brake system after it lias been 
subjected to fade and recovery testing under 
S5.1.4. Manufacturer comments indicated that, 
in the case of school buses with a GVWR gi-eater 
than 10,000 pounds, use of a "hot" burnish pro- 
cedure (S7.4.2.1.2) in combination with the 
standard's fade and recovery testing makes the 
fourth effectiveness test redundant. NHTSA 
analysis agrees with these arguments, and in view 
of the fact that the hot burnish option will be- 
come the only permissible method of conditioning 
the brakes after September 1, 1976, the proposed 
fourth effectiveness test for heavier school buses 
is not adopted. 

Since use of the hot burnish procedure was 
an important factor in the decision to drop the 
fourth effectiveness requirement for vehicles over 
10,000 pounds GVWE, the NHTSA denies the 



Wagner petition to extend the alternative burnish 
procedures under S7.4.2.1 after the scheduled 
deletion of that option on September 1, 1976. 
Because this option ends before the standard's 
effectiveness for school buses, S7.4.2.1 has been 
simplified by eliminating the cold burnish pro- 
cedure, (S7.4.2.1.1) that will not be used. 

The NHTSA also notes General Motors' argu- 
ment that the fourth effectiveness test should be 
eliminated for vehicle classes offered with either 
hydraulic or air brakes simply because there is 
no comparable rexjuirement in Standard No. 121, 
Air Brake Systems. While the NHTSA agrees 
that vehicle classes ideally might be subjected 
to identical requirements whatever the method 
of brake actuation, formulation of any desired 
compatibility between hydraulic and air-braked 
vehicles of the same weight class must be accom- 
plished separately from this rulemaking on 
school buses, which is subject to a statutory dead- 
line. General Motors' view will be considered 
in future rulemaking. 

The April 28 notice proposed deletion, for 
school buses, of the option methods for testing 
the service brake system in the event the brake 
power assist or brake power unit failed (S5.1.3). 
The only comment received was from the VESC, 
which misunderstood the proposal as deleting all 
tests of a failed power assist or power unit. In 
fact, school buses will be required to meet 
S5. 1.3.1 as hereby amended. The VESC mis- 
understanding may have arisen because of un- 
clear language used in proposing an amendment 
of the test procedure of S7.10 that underlies the 
requirement. Section S7.10 is appropriately re- 
vised in this amendment of the standard. 

The NHTSA proposed more stringent fade 
and recovery performance for school buses than 
the SAE's recommended levels for other truck- 
type veliicles, because of the distinctive school 
bus duty cycle. School buses make a high num- 
ber of stops compared to the truck-type vehicles 
which may share common components. These 
stops are usually made on secondary roads that 
often have steeper grades than the primary road 
system. The National School Transportation 
Association (NSTA) confirmed in statements 
before an NHTSA public meeting on hydraulic 
brakes that the association's experience indicated 



PART 571; S 105-75— PRE 39 



Effecrive: October 12, 1976 



inadequate fade resistance in some of today's 
school buses. While NHTSA testing indicates 
that some buses already conform to this require- 
ment, other buses will be required to upgrade 
their brake systems to conform to this minimum 
performance level. 

Three manufacturers objected to this perform- 
ance level and each suggested a different modifi- 
cation of the proposed requirement to reduce its 
stringency. Ford requested a 200-pound allow- 
able pedal force for the first five stops, stating 
that "The 60 mph fade sequence represents, in 
Ford's opinion, an extreme condition that would 
rarely, if ever, be duplicated in normal customer 
operation of school buses." Wagner stated "It 
is inconsistent to require one degree of vehicle 
braking for the Effectiveness Test and another 
(in this case, more powerful) for the Fade and 
Recovery. . . . We agree in the need for some 
measure of fade and recovery but the redundancy 
of two such requirements in a minimum standard 
has not been addressed. . . ." General Motors 
cited the good safety record of school buses, ques- 
tioned the adequacy of NHTSA testing, and 
stated, with regard to school buses with a GV^VVR 
of more than 10,000 pounds, ". . . . the NHTSA 
has proposed stringent fade and recovei-y require- 
ments which far exceed minimum performance 
requirements." 

"Minimum" performance standards do not 
equate with "minimal" performance standards, 
as implied by General Motors and Wagner. The 
word "minimum" in the statutory definition of 
motor vehicle safety standards (15 U.S.C. § 1391- 
(2)), does not refer to the substantive content of 
the standards but rather to their legal status — 
that the products covered must not fall short of 
them. 

Wagner considered it inconsistent to specify a 
performance level for the fade characteristics of 
a braking system that would have the effect of 
improving another characteristic of the braking 
system (stopping distance performance) beyond 
the minimum level specified in the standard. The 
NHTSA disagrees, and considers it appropriate 
to specify the minimum fade perfonnance neces- 
sary to assure adequate performance of brakes 
in stop-and-go operation, whether or not satis- 
faction of this minimum level results in a brake 



system with better stopping distance performance 
than required by the standard. 

Wliile Ford is correct that the test sequence 
typically will not be experienced in day-to-day 
operations, that does not rule out the need for 
the improved fade characteristics suggested by 
the NSTA. Each of the commenters claims that 
the fade and recovery characteristics do exceed 
the poorest performance of some existing vehicles, 
but none presented convincing justification for 
their positions that the proposed levels are in- 
appropriate for school bus braking systems. It 
is also noted that school buses with a GVWR 
of more than 10,000 pounds no longer have to 
meet the high-speed or fourth effectiveness re- 
quirements. With regard to Ford's suggestion 
of permitting a 200-pound pedal control force, 
the NHTSA continues to consider a 150-pound 
maximum necessary in view of the large per- 
centage of school bus operators that are women 
(see HSRI Report No. HuF-6, NBS Technical 
Note 557, October 1970, "The Brake Pedal Force 
Capability of Adult Females"). Accordingly, 
the fade and recovery performance values are 
promulgated as proposed. The proposed word- 
ing of S5.1.4.3(b) (2) is modified for clarity in 
response to Wagner's request. 

The proposal included a minimum performance 
level for the ability of school bus brakes to per- 
form after they are soaked with water. Three 
comments were received that objected to the pro- 
posed performance levels. Wagner also objected 
that the test conditions were stated with insuf- 
ficient specificity. The width of the water trough 
used to wet the brakes is not specified and the 
width may affect the degree of wetting achieved 
in large truck tire sizes. The NHTSA intends 
to address this issue in its upcoming proposal on 
test intei-vals in the water recovery test. 

For the present NHTSA will resolve differ- 
ences in this test condition in the manufacturer's 
favor if they affect the outcome of testing. 

General Motore' only objection to inclusion of 
a water recovery test in this standard for school 
buses over 10,000 pounds G\'^WR was that a 
comparable test in Standard No. 121 has not been 
developed. The NHTSA is not, of course, limited 
in the breadth of one standard by the breadth 
of another, whether or not they measure the same 
aspect of performance of a vehicle. 



PART 571; S 105-75— PRE 40 



International was the only manufacturer to 
provide data indicating that its vehicles are not 
capable of meeting the water recovery test in all 
cases. The NHTSA concludes that other manu- 
facturers' products are capable of meeting the 
levels established in the standard. The NHTSA 
denies International's request to permit a 1.5- 
mile "drying-off" period between wet stops, be- 
cause it would negate for the most part the effect 
of soaking. 

Therefore, the only modification of water re- 
covery testing from that proposed is to clarify 
the wording of the minimum permissible control 
force (S5.1.5.2(b) (2)) as requested by Wagner. 

The spike stop and parking brake requirements 
are amended as proposed. 

The test procedures contained in S6.1, S6.2, 
S7.5, S7.7.1, and S7.10 are revised as appropriate 
to reflect the amended requirements. 

Wagner, Ford, General Motors, and Inter- 
national requested that the brake fluid level indi- 
cator not be required for school buses. The 
NHTSA will make its decision in this area 
shortly and will publish its response to the issues 
raised in this rulemaking. 

Ford also asked that the parking brake warn- 
ing indicator be deleted from school bus require- 
ments as a luxury. The NHTSA has never 
considered this signal to be a luxury, and con- 
siders it important to prevent a partially-applied 
brake from overheating, reducing its efficiency. 
Ford's request is therefore denied. 

Wagner proposed that the present speed range 
for brake warming in S7.1 and S7.2 (40-to-lO- 
mph snubs) be increased to a range of 50-to-20- 
mph snubs. The agency has seen no evidence 
in its test program of the inadequacy of present 
values, and therefore denies the Wagner request, 
which was not supported by any data. 

The California Department of Highway Patrol 
(CHP) raised the issue of the adequacy of the 
standard from the enforcement perspective, 
particularly the complexity of the stopping dis- 
tance requirements for use in vehicle-in-use in- 
spection. As noted in a recent notice on air 
brakes (40 FR 56920, December 5, 1975), new 
vehicle braking standards may be inappropriate 
for a State inspection program, because they are 
not designed to measure degradation of equip- 
ment and performance over a period of time. 



Effective: October 12, 1976 

Since degradation of the brake system is not 
addressed by Standard No. 105-75, the CHP is 
not prevented by the National Traffic and Motor 
Vehicle Safety Act (15 U.S.C. 1392(d)) from 
enforcing requirements that measure the condi- 
tion of the vehicle, as long as they do not dictate 
the design or performance of new vehicles. 

The CHP recommendations for vacuum gauge 
and vacuum failure requirements on school buses 
equipped with vacuum-boosted brakes are being 
taken under consideration in regard to future 
rulemaking for truck, bus, and multi-purpose 
passenger vehicle hydraulic braking standards. 

SWS Silicon Corporation's comments on DOT 
5 brake fluid are noted, and comments of any 
interested person on the subject of appropriate 
brake fluids for school buses are solicited. 

In an area unrelated to the applicability of 
the standard to school buses, persons have re- 
quested clarification of an amendment of the 
standard published September 17, 1975 (40 FR 
42872). Section S5.1.5.2(a) consists of an open- 
ing paragraph, two numbered subparagraphs, 
and a concluding paragraph. Subparagraph 
"(2)" was set forth in its entirety in a revised 
form in that September action, and it was not 
clear whether the concluding paragraph that fol- 
lows it remained unchanged or was eliminated 
in the revision. For clarification, it is noted 
that only the subparagraph "(2)" was revised 
and that the concluding paragraph remains in 
the standard unchanged. 

In consideration of the foregoing. Standard 
No. 105-75 (49 CFR 571.105-75) is. . . . 

Effective date: Oct. 12, 1976. The effective 
date of this amendment is established as 9 months 
after the date of its issuance, as required by the 
Motor "Vehicle and Schoolbus Safety Amend- 
ments of 1974, Pub. L. 93-492, section 202 (15 
U.S.C. 1397(i)(l)(A)). 

(Sec. 103, 119, Pub. L. 89-563, 80 Stat. 718 
(15 U.S.C. 1392, 1407) ; § 202, Pub. L. 93-492, 
88 Stat. 1470 (15 U.S.C. 1392); delegation of 
authority at 49 CFR 1.50) 

Issued on January 12, 1976. 

James B. Gregory 
Administrator 
41 F.R. 2391 
January 16, 1976 



PART 571: S 105-75— PRE 41^2 



International was the only manufacturer to 
provide data indicating that its vehicles are not 
capable of meeting the water recovery test in all 
cases. The NHTSA concludes that other manu- 
facturers' products are capable of meeting the 
levels established in the standard. The NHTSA 
denies International's request to permit a 1.5- 
mile "drying-oflF" period between wet stops, be- 
cause it would negate for the most part the effect 
of soaking. 

Therefore, the only modification of water re- 
covery testing from that proposed is to clarify 
the wording of the minimum permissible control 
force (S5.1.5.2(b) (2)) as requested by Wagner. 

The spike stop and parking brake requirements 
are amended as proposed. 

The test procedures contained in S6.1, S6.2, 
S7.5, S7.7.1, and S7.10 are revised as appropriate 
to reflect the amended requirements. 

Wagner, Ford, General Motors, and Inter- 
national requested that the brake fluid level indi- 
cator not be required for school buses. The 
NHTSA will make its decision in this area 
shortly and will publish its response to the issues 
raised in this rulemaking. 

Ford also asked that the parking brake warn- 
ing indicator be deleted from school bus require- 
ments as a luxury. The NHTSA has never 
considered this signal to be a luxury, and con- 
siders it important to prevent a partially-applied 
brake from overheating, reducing its efficiency. 
Ford's request is therefore denied. 

Wagner proposed that the present speed range 
for brake warming in S7.1 and S7.2 (40-to-lO- 
mph snubs) be increased to a range of 50-to-20- 
mph snubs. The agency has seen no evidence 
in its test program of the inadequacy of present 
values, and therefore denies the Wagner request, 
which was not supported by any data. 

The California Department of Highway Patrol 
(CHP) raised the issue of the adequacy of the 
standard from the enforcement perspective, 
particularly the complexity of the stopping dis- 
tance requirements for use in vehicle-in-use in- 
spection. As noted in a recent notice on air 
brakes (40 FK 56920, December 5, 1975), new 
vehicle braking standards may be inappropriate 
for a State inspection program, because they are 
not designed to measure degradation of equip- 
ment and performance over a period of time. 



Effective: October 12, 1976 

Since degradation of the brake system is not 
addressed by Standard No. 105-75, the CHP is 
not prevented by the National Traffic and Motor 
Vehicle Safety Act (15 U.S.C. 1392(d)) from 
enforcing requirements that measure the condi- 
tion of the vehicle, as long as they do not dictate 
the design or performance of new vehicles. 

The CHP recommendations for vacuum gauge 
and vacuum failure requirements on school buses 
equipped with vacuum-boosted brakes are being 
taken under consideration in regard to future 
rulemaking for truck, bus, and multi-purpose 
passenger vehicle hydraulic braking standards. 

SWS Silicon Corporation's comments on DOT 
5 brake fluid are noted, and comments of any 
interested person on the subject of appropriate 
brake fluids for school buses are solicited. 

In an area unrelated to the applicability of 
the standard to school buses, persons have re- 
quested clarification of an amendment of the 
standard published September 17, 1975 (40 FR 
42872). Section S5.1.5.2(a) consists of an open- 
ing paragraph, two numbered subparagraphs, 
and a concluding paragraph. Subparagraph 
"(2)" was set forth in its entirety in a revised 
form in that September action, and it was not 
clear whether the concluding paragraph that fol- 
lows it remained unchanged or was eliminated 
in the re\'ision. For clarification, it is noted 
that only the subparagraph "(2)" was revised 
and that the concluding paragraph remains in 
the standard unchanged. 

In consideration of the foregoing, Standard 
No. 105-75 (49 CFR 571.105-75) is. . . . 

Eifective date: Oct. 12, 1976. The effective 
date of this amendment is established as 9 months 
after the date of its issuance, as required by the 
Motor Vehicle and Schoolbus Safety Amend- 
ments of 1974, Pub. L. 93-492, section 202 (15 
U.S.C. 1397(i)(l)(A)). 

(Sec. 103, 119, Pub. L. 89-563, 80 Stat. 718 
(15 U.S.C. 1392, 1407) ; § 202, Pub. L. 93-492, 
88 Stat. 1470 (15 U.S.C. 1392) ; delegation of 
authority at 49 CFR 1.50) 

Issued on January 12, 1976. 

James B. Gregory 
Administrator 
41 F.R. 2391 
January 16, 1976 



PART 571; S 105-75— PRE 41-42 



EffecHve: April 22, 1976 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 

Hydraulic Brake Systems 
(Docket No. 70-27; Notice 18) 



This notice amends Standard No. 105-75, 
Hydraulic Brake Systems, to permit a manufac- 
turer to provide either a gross loss of pressure 
indicator (GLPI) or a low brake fluid level indi- 
cator (BFLI) in satisfaction of the hydraulic 
failure indicator requirements of S5.3.1. 

This amendment of Standard No. 105-75 (49 
CFR 571.105-75) was proposed in response to 
petitions from Ford Motor Company, Wagner 
Electric Corporation, and Mercedes-Benz of 
North America, Inc., as well as the comments of 
other manufacturers of hydraulic-braked motor 
vehicles (41 FR 2828, January 20, 1976). 

Comments were received from General Motors 
Corporation, Bob Ingham, Jr., Chrysler Corpora- 
tion, Wagner Electric Corporation, the Cali- 
fornia Department of Highway Patrol (CHP), 
Professor P. N. Joubert, Bendix Corporation, 
British Leyland UK Limited, the Vehicle Equip- 
ment Safety Commission, Ford Motor Company, 
Bayerische Motoren Werke, and the Department 
of Transport of Australia. The National Motor 
Vehicle Safety Advisory Council made no com- 
ment on the proposal. 

All commenters except the CHP, VESC, De- 
partment of Transport of Australia, and Profes- 
sor Joubert endorsed the amendment as proposed 
and urged its swift implementation. 

The CHP recommended that the proposed op- 
tion be allowed only until the availability and 
reliability problems associated with the BFLI 
are resolved, at which time the BFLI would be 
required on all vehicles. The VESC also recom- 
mended a requirement for both of the devices or 
the BFLI alone. It is the opinion of the CHP 
that the apparent benefit of a GLPI is not real, 
because the GLPI warning activates only after 
failure has occurred, when increased pedal travel 
and decreased stopping performance have al- 



ready warned of the faulty condition. However, 
the failure of one subsystem in split system ve- 
hicles, particularly that to the rear wheels, easily 
may go unnoticed during the low rate-of- 
deceleration stops encountered in normal driving. 
In this vast majority of cases, the driver will be 
warned of the failure by the GLPI before the 
brake failure is apparent, a substantial benefit in 
averting accidents. 

Each of the four commenters who did not 
support the proposal found fault with the 
NHTSA's use of the extremely limited accident 
data from the Indiana University Institute for 
Research in Public Safety study {Tri-Level 
Study of the Causes of Traffic Accidents, DOT- 
HS-801-335, January, 1975). The four com- 
menters apparently interpreted Notice 17 to 
mean that the NHTSA had concluded, based on 
this small amount of data, that the BFLI was 
not cost-effective. Such is not the case. The 
NHTSA's evaluation of the Indiana study only 
concluded that its earlier judgement that both 
warnings were justified was cast in some doubt 
by the limited data generated since that initial 
decision was made. The NHTSA believes that 
the doubt is sufficient to justify dropping the 
simultaneous requirement for both devices. 

As noted by the CHP, the accident data are 
not yet available to quantitatively prove the com- 
parative benefits of one warning system over the 
other. Although the four dissenting comment- 
ers expressed a preference for the BFLI, the 
NHTSA feels that there is insufficient evidence 
of its superiority to mandate its use in place of 
the GLPI. The NHTSA believes that a con- 
tinuation of the option previously available 
under Standard No. 105 is in the public interest. 

Ford Motor Company pointed out that the 
proposed wording of S7.9.1, which refers to a 



PART 571; S 105-75— PRE 43 



,^ 



Effective: April 22, 1976 

"brake system failure indicator," was inconsistent 
with other references in the standard, and sug- 
gested that the word "failure" be removed. The 
reference has been changed to read "brake system 
indicator lamp" to be consistent with S5.3. Sec- 
tion S7.9.4 also is reworded for the same reason. 

In a matter unrelated to the BFLI proposal, 
the agency hereby corrects an inadvertent omis- 
sion of a conforming amendment that should 
have accompanied the major amendment making 
the standard applicable to school buses (41 FR 
2391, January 16, 1976). The reference to 
"S7.4.2.1.2" in S6 is changed to "S7.4.2.1." 

In consideration of the foregoing, Standard 
No. 105-75 (49 CFR 571.105-75) is amended. . . . 



Effective date: April 22, 1976. Because this 
amendment creates no additional requirements 
for any person and because of the manufacturers' 
need to know as soon as possible the vehicle re- 
quirements for the upcoming model year for 
planning purposes, it is found that an immediate 
eflFective date is in the public interest. 

(Sec. 103, 119, Pub. L. 89-563, 80 Stat. 718 
(15 U.S.C. 1392, 1407) ; delegations of authority 
at 49 CFR 1.50 and 49 CFR 501.8.) 

Issued on April 14, 1976. 

James B. Gregory 
Administrator 

41 F.R. 16803 
April 22, 1976 



PART 571; S 105-75— PRE 44 



Effecrive: April 22, 1976 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 

Hydraulic Brake Systems 
(Docket No. 70-27; Notice 18) 



This notice amends Standard No. 105-75, 
Hydraulic Brake Systems^ to permit a manufac- 
turer to provide either a gross loss of pressure 
indicator (GLPI) or a low brake fluid level indi- 
cator (BFLI) in satisfaction of the hydraulic 
failure indicator requirements of S5.3.1. 

This amendment of Standard No. 105-75 (49 
CFR 571.105-75) was proposed in response to 
petitions from Ford Motor Company, Wagner 
Electric Corporation, and Mercedes-Benz of 
North America, Inc., as well as the comments of 
other manufacturers of hydraulic-braked motor 
vehicles (41 FR 2828, January 20, 1976). 

Comments were received from General Motors 
Corporation, Bob Ingham, Jr., Chrysler Corpora- 
tion, Wagner Electric Corporation, the Cali- 
fornia Department of Highway Patrol (CHP), 
Professor P. N. Joubert, Bendix Corporation, 
British Leyland UK Limited, the Vehicle Equip- 
ment Safety Commission, Ford Motor Company, 
Bayerische Motoren Werke, and the Department 
of Transport of Australia. The National Motor 
Vehicle Safety Advisory Council made no com- 
ment on the proposal. 

All commenters except the CHP, VESC, De- 
partment of Transport of Australia, and Profes- 
sor Joubert endorsed the amendment as proposed 
and urged its swift implementation. 

The CHP recommended that the proposed op- 
tion be allowed only until the availability and 
reliability problems associated with the BFLI 
are resolved, at which time the BFLI would be 
required on all vehicles. The VESC also recom- 
mended a requirement for both of the devices or 
the BFLI alone. It is the opinion of the CHP 
that the apparent benefit of a GLPI is not real, 
because the GLPI warning activates only after 
failure has occurred, when increased pedal travel 
and decreased stopping performance have al- 



ready warned of the faulty condition. However, 
the failure of one subsystem in split system ve- 
hicles, particularly that to the rear wheels, easily 
may go unnoticed during the low rate-of- 
deceleration stops encountered in normal driving. 
In this vast majority of cases, the driver will be 
warned of the failure by the GLPI before the 
brake failure is apparent, a substantial benefit in 
averting accidents. 

Each of the four commenters who did not 
support the proposal found fault with the 
NHTSA's use of the extremely limited accident 
data from the Indiana University Institute for 
Research in Public Safety study {Tri-Level 
Stitdy of the Causes of Traffic Accidents, DOT- 
HS-801-335, January, 1975). The four com- 
menters apparently interpreted Notice 17 to 
mean that the NHTSA had concluded, based on 
this small amount of data, that the BFLI was 
not cost-effective. Such is not the case. The 
NHTSA's evaluation of the Indiana study only 
concluded that its earlier judgement that both 
warnings were justified was cast in some doubt 
by the limited data generated since that initial 
decision was made. The NHTSA believes that 
the doubt is sufficient to justify dropping the 
simultaneous requirement for both devices. 

As noted by the CHP, the accident data are 
not yet available to quantitatively prove the com- 
parative benefits of one warning system over the 
other. Although the four dissenting comment- 
ers expressed a preference for the BFLI, the 
NHTSA feels that there is insufficient evidence 
of its superiority to mandate its use in place of 
the GLPI. The NHTSA believes that a con- 
tinuation of the option previously available 
under Standard No. 105 is in the public interest. 

Ford Motor Company pointed out that the 
proposed wording of S7.9.1, which refers to a 



PART 571; S 105-75— PRE 43 



Effective: April 22, 1976 

"brake system failure indicator," was inconsistent 
with other references in the standard, and sug- 
gested that the word "faihire" be removed. The 
reference has been changed to read "brake system 
indicator lamp" to be consistent with S5.3. Sec- 
tion S7.9.4 also is reworded for the same reason. 

In a matter unrelated to the BFLI proposal, 
the agency hereby corrects an inadvertent omis- 
sion of a conforming amendment that should 
have accompanied the major amendment making 
the standard applicable to school buses (41 FR 
2391, January 16, 1976). The reference to 
"S7.4.2.1.2" in S6 is changed to "S7.4.2.1." 

In consideration of the foregoing, Standard 
No. 105-75 (49 CFR 571.105-75) is amended. . . . 



Effective date: April 22, 1976. Because this 
amendment creates no additional requirements 
for any person and because of the manufacturers' 
need to know as soon as possible the vehicle re- 
quirements for the upcoming model year for 
planning purposes, it is found that an immediate 
effective date is in the public interest. 

(Sec. 103, 119, Pub. L. 89-563, 80 Stat. 718 
(15 U.S.C. 1392, 1407) ; delegations of authority 
at 49 CFR 1.50 and 49 CFR 501.8.) 

Issued on April 14, 1976. 

James B. Gregory 
Administrator 

41 F.R. 16803 
April 22, 1976 



PART 571; S 105-75— PRE 44 



Effective: June 14, 1976 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 

Hydraulic Brake Systems 
(Docket No. 75-27; Notice 4) 



This notice amends Standard No. 105-75, 
Hydraulic Brake Systems, and Standard No. 122, 
Motorcycle Brake Systetns, to modify the means 
for establishing the frictional resistance of the 
surface on which stopping distance tests are con- 
ducted. A similar amendment is made to Part 
575, Consumer Injormation, of Title 49 of the 
Code of Federal Regulations. 

The National Highway TraflSc Safety Admin- 
istration (NHTSA) proposed the change in 
Standard No. 105-75 (49 CFR 571.105-75), 
Standard No. 121, Air Brake Systems (49 CFR 
571.121), Standard No. 122 (49 CFR 571.122), 
and the Consumer Information Regulations (49 
CFR 575.101) in response to a petition from 
British-Leyland Motors Limited (40 FR 45200. 
October 1, 1975). The existing test procedure in 
these regulations has specihed use of the Ameri- 
can Society for Testing and Materials (ASTM) 
E-274-65T procedure, using an ASTM E249 tire 
that is no longer manufactured. 

Responses were received on the proposed 
ASTM change from Wliite Motor Corporation 
("VVliite), Mack Trucks, Inc. (Mack), Freight- 
liner Corporation (Freight liner). Ford Motor 
Company (Foid), General Motors Corporation 
(GM), Chrysler Corporation (Chrysler), Ameri- 
can Motors Corporation (AMC), and Interna- 
tional Harvester (IH). The National Motor 
Vehicle Safety Advisory Council made no com- 
ment on the proposal. 

Most commenters supported use of the new 
test procedure and tire, although they differed in 
recommendations for correlating the reading pro- 
duced under the new procedure with that pro- 
duced under the old procedure. Manufacturers 
are presently certifying compliance to brake 
standards on test surfaces with a satisfactory 
reading under the old procedure, and they should 



be able to continue testing and certifying com- 
pliance on the same surface without any increase 
in the severity of the tests. To accomplish this 
transition, the correlation in readings between 
the procedures has been determined, and the dif- 
ference is reflected in a change of the dry surface 
value from "skid number" 75 to "skid number" 
81. 

Freightliner urged postponement of any action 
until it could be supported by "adequate and 
statistically reliable test data." AMS also re- 
ommended that the NHTSA do nothing "until 
the industry has had sufficient time to evaluate 
and verify the performance of the ASTM E501 
test tire on all types of surfaces." 

The change in procedure is prompted by the 
ASTM decision to utilize a new tire in ascertain- 
ing the frictional coefficient of test surfaces. As 
a result the old tire is no longer manufactured 
and only the new tire is available for skid num- 
ber measurement. Manufacturers have conducted 
comparative tests with the new tire to determine 
the correlation between the readings given by the 
two tires. Neither Freightliner nor AMC sub- 
mitted data showing that the agency's proposal 
to adjust the dry surface skid number upwards 
is unjustified. Only Mack submitted data and it 
supported the NHTSA and Federal Highway 
Administration test data that have been placed 
in the docket. General Motors considered the 
agency's proposed upward adjustment to be the 
maximum desirable based on its data. Interna- 
tional Harvester, Chrysler, and Ford supported 
the change in dry surface skid number without 
qualification, and Wliite suggested that a skid 
number of 85 be utilized. The agency finds that 
the AMC and Freightliner requests for further 
delay are unjustified. 



PART 571; S 105-75— PRE 45 



Effective: June 14, 1976 

Ford and Freightliner asked that the skid 
number for the lower coefficient (wet) surface 
also be adjusted. The agency's purpose in pro- 
posing the adjustment is limited to changes 
necessary to avoid a modification of the test sur- 
faces or an increase in the severity of perform- 
ance levels specified under the safety standards. 
The NHTSA earlier concluded that change of 
the wet surface specification was unnecessary, and 
no evidence has been supplied that would modify 
the earlier determination. 

General Motors noted that an editorial change 
to the newer ASTM procedure does not appear 
in early publications of that procedure. To put 
all interested persons on notice of the editorial 
change, the NHTSA has included the change in 
its references to the ASTM E274-70 procedure. 

Freightliner asserted that tlie newer procedure 
included modification of a formula that justified 
a larger upwards adjustment than that proposed 
by the agency. Actually, the modifications only 
corrected an error in the earlier formula which 
had no effect on the determination of f rictional 
coefficient. Manufacturers either utilized a test 
trailer that obviated the need for calculations 
using the formula, or were aware of the error 
and corrected for it in their calculations. Thus 
the adjustment requested by Freightliner is not 
warranted. 

In accordance with recently-enunciated De- 
partment of Transportation policy encouraging 
adequate analysis of the consequences of regula- 
tory action (41 FK 16201, April 16, 1976), the 
agency herewith summarizes its evaluation of the 
economic and other consequences of this amend- 
ment on the public and private sectors, including 
possible loss of safety benefit. Because the new 
references to procedures and a test tire are ex- 
pected to accord with existing practices, the 
amendment is judged not to have any significant 



impact on costs or benefits of the standards and 
consumer information item that are modified by 
the change. 

Standard No. 121, Air Brake Systems, is pres- 
ently subject to judicial review under § 105(a) 
of the National Traffic and Motor Vehicle Safety 
Act (15 U.S.C. § 1394(a)). The U.S. Court of 
Appeals hearing the petition for review has in- 
dicated that it prefers to review the standard as 
it presently exists, without unnecessary amend- 
ment. To the degree possible, the agency is 
complying with that request and therefore, in the 
case of Standard No. 121, will delay the update 
of ASTM procedure until review is completed. 

It is noted that this change in procedure for 
ascertaining the fractional resistance of the test 
surface does not invalidate data collected using 
the older procedure, and manufacturers can pre- 
sumably certify on the basis of stopping distance 
tests conducted on sufaces measured by the old 
tire. 

In consideration of the foregoing, amendments 
are made in Chapter V of Title 49, Code of 
Federal Regulations. 

Effective date: June 14, 1976. Because the 
older test tire is no longer manufactured, and 
because the amendment of procedure and test tire 
is intended only to duplicate the existing proce- 
dure and tire, this amendment creates no addi- 
tional requirements for any person, and an 
immediate effective date is found to be in the 
public interest. 

(Sec. 103, 119, Pub. L. 89-563, 80 Stat. 718 
(15 U.S.C. 1392, 1407); delegation of authority 
at 49 CFR 1.50.) 

Issued on June 8, 1976. 

James B. Gregory 
Administrator 

41 F.R. 24592 
June 17, 1976 



PART 571; S 105-75— PRE 46 



Effective: June 14, 1976 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 

Hydraulic Brake Systems 
(Docket No. 75-27; Notice 4) 



This notice amends Standard No. 105-75, 
Hydraulic Brake Systems, and Standard No. 122, 
Motorcycle Brake Systems, to modify the means 
for establishing the frictional resistance of the 
surface on which stopping distance tests are con- 
ducted. A similar amendment is made to Part 
575, Consumer Information, of Title 49 of the 
Code of Federal Kegulations. 

The National Highway Traffic Safety Admin- 
istration (NHTSA) proposed the change in 
Standard No. 105-75 (49 CFR 571.105-75), 
Standard No. 121, Air Brake Systems (49 CFR 
571.121), Standard No. 122 (49 CFR 571.122), 
and the Consumer Information Regulations (49 
CFR 575.101) in response to a petition from 
British-Leyland Motors Limited (40 FR 45200, 
October 1, 1975). The existing test procedure in 
these regulations has specihed use of the Ameri- 
can Society for Testing and Materials (ASTM) 
E-274-65T procedure, using an ASTM E249 tire 
that is no longer manufactured. 

Responses were received on the proposed 
ASTM change from "VVliite Motor Corporation 
(Wliite), Mack Trucks, Inc. (Mack), Freight- 
liner Corporation (Freightliner), Ford Motor 
Company (Foi-d), General Motors Corporation 
(GM), Chrysler Corporation (Chrysler), Ameri- 
can Motors Corporation (AMC), and Interna- 
tional Harvester (IH). The National Motor 
Vehicle Safety Advisory Council made no com- 
ment on the proposal. 

Most commenters supported use of the new 
test pi'ocedure and tire, although they differed in 
recommendations for correlating the reading pro- 
duced under the new procedure with that pro- 
duced under the old procedure. Manufacturers 
are presently certifying compliance to brake 
standards on test surfaces with a satisfactory 
reading under the old procedure, and they should 



be able to continue testing and certifying com- 
pliance on the same surface without any increase 
in the severity of the tests. To accomplish this 
transition, the correlation in readings between 
the procedures has been determined, and the dif- 
ference is reflected in a change of the dry surface 
value from "skid nimiber" 75 to "skid number" 
81. 

Freightliner urged postponement of any action 
until it could be supported by "adequate and 
statistically reliable test data." AMS also re- 
ommended that the NHTSA do nothing "until 
the industry has had sufficient time to evaluate 
and verify the performance of the ASTM E501 
test tire on all types of surfaces." 

The change in procedure is prompted by the 
ASTM decision to utilize a new tire in ascertain- 
ing the frictional coefficient of test surfaces. As 
a result the old tire is no longer manufactured 
and only the new tire is available for skid num- 
ber measurement. Manufacturers have conducted 
comparative tests with the new tire to determine 
the correlation between the readings given by the 
two tires. Neither Freightliner nor AMC sub- 
mitted data showing that the agency's proposal 
to adjust the dry surface skid number upwards 
is unjustified. Only Mack submitted data and it 
supported the NHTSA and Federal Highway 
Administration test data that have been placed 
in the docket. General Motors considered the 
agency's proposed upward adjustment to be the 
maximum desirable based on its data. Interna- 
tional Harvester, Chrysler, and Ford supported 
the change in dry surface skid number without 
qualification, and White suggested that a skid 
number of 85 be utilized. The agency finds that 
the AMC and Freightliner requests for further 
delay are unjustified. 



PART 571; S 105-75— PRE 45 



Effective: June 14, 1976 

Ford and Freightliner asked that the skid 
number for the lower coeificient (wet) surface 
also be adjusted. The agency's purpose in pro- 
posing the adjustment is limited to changes 
necessary to avoid a modification of the test sur- 
faces or an increase in the severity of perform- 
ance levels specified under the safety standai'ds. 
The NHTSA earlier concluded that change of 
the wet surface specification was unnecessary, and 
no evidence has been supplied that would modify 
the earlier determination. 

General Motors noted that an editorial change 
to the newer ASTM procedure does not appear 
in early publications of that procedure. To put 
all interested persons on notice of the editorial 
change, the NHTSA has included the change in 
its references to the ASTM E274-70 procedure. 

Freightliner asserted that the newer procedure 
included modification of a formula that justified 
a larger upwards adjustment than that proposed 
by the agency. Actually, the modifications only 
corrected an error in the earlier formula which 
had no effect on the determination of frictional 
coefficient. Manufacturers either utilized a test 
trailer that obviated the need for calculations 
using the formula, or were aware of the error 
and corrected for it in their calculations. Thus 
the adjustment requested by Freightliner is not 
warranted. 

In accordance with recently-enunciated De- 
partment of Transportation policy encouraging 
adequate analysis of the consequences of regula- 
tory action (41 FR 16201, April 16, 1976), the 
agency herewith summarizes its evaluation of the 
economic and other consequences of this amend- 
ment on the public and private sectors, including 
possible loss of safety benefit. Because the new 
references to procedures and a test tire are ex- 
pected to accord with existing practices, the 
amendment is judged not to have any significant 



impact on costs or benefits of the standards and 
consumer information item that are modified by 
the change. 

Standard No. 121, Air Brake Systems, is pres- 
ently subject to judicial review under § 105(a) 
of the National Traffic and Motor Vehicle Safety 
Act (15 U.S.C. § 1394(a)). The U.S. Court of 
Appeals hearing the petition for review has in- 
dicated that it prefers to review the standard as 
it presently exists, without unnecessary amend- 
ment. To the degree possible, the agency is 
complying with that request and therefore, in the 
case of Standard No. 121, will delay the update 
of ASTM procedure until review is completed. 

It is noted that this change in procedure for 
ascertaining the frictional resistance of the test 
surface does not invalidate data collected using 
the older procedure, and manufacturers can pre- 
sumably certify on the basis of stopping distance 
tests conducted on sufaces measured by the old 
tire. 

In consideration of the foregoing, amendments 
are made in Chapter V of Title 49, Code of 
Federal Regulations. 

Effective date: June 14, 1976. Because the 
older test tire is no longer manufactured, and 
because the amendment of procedure and test tire 
is intended only to duplicate the existing proce- 
dure and tire, this amendment creates no addi- 
tional requirements for any person, and an 
immediate effective date is found to be in the 
public interest. 

(Sec. 103, 119, Pub. L. 89-563, 80 Stat. 718 
(15 U.S.C. 1392, 1407) ; delegation of authority 
at 49 CFR 1.50.) 

Issued on June 8, 1976. 

James B. Gregory 
Administrator 

41 F.R. 24592 
June 17, 1976 



PART 571; S 105-75— PRE 46 



Effective: July 19, 1976 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 

Hydraulic Brake Systems 
(Docket Nos. 75-7; 75-16; Notices 3, 9) 



This notice republishes in their entirely Stand- 
ard No. 105-75, Hydraulic Brake Systems^ and 
Standard No. 121, Air Brake Systems, because 
the number and complexity of recent amendments 
to these standards may have created confusion 
for some interested pereons. 

Standard No. 105-75 (49 CFE 571.105-75) was 
issued September 1972 (37 FR 17970, September 
2, 1972) and has been amended numerous times 
since issuance. Although an up-to-date and com- 
plete text of the standard appears each year in 
the republished Code of Federal Regulations, 
several complex amendments have been made to 
the standard in the past year that are not re- 
flected in the most recent up-to-date text. To 
assist interested persons who must be certain of 
the text's provisions, the agency herewith pub- 
lishes the standard in its entirety. Interested 
persons are advised that amendments of Stand- 
ard No. 105-75 may occur in the future, although 
no proposals are outstanding at this time. 

In a related matter. General Motors Cor^jora- 
tion has brought to the agency's attention an 
inadvertent deletion of one sentence from one 
section of Standard No. 105-75. A statement 
was added to the text of S5.1.5.2(a) (2) to per- 
mit an interim increase in permissible control 
force for the fifth wet recovexy stop (40 FR 
24525, June 9, 1975). Inadvertently, this sen- 
tence was deleted from S5. 1.5.2(a) (2) in a sub- 
sequent rulemaking action (40 FR 42872, 
September 17, 1976), although the preamble to 
the notice made clear that "The new wording in 
no way modifies the meaning of S5,1.4(a) (2) 
and S5.1.5.2(a) (2)." To correct this omission, 
the sentence appears in this publication. It has 



been moved to S5. 1.5.2(a) (1) because it concerns 
the maximum pedal force limit in that section, 
rather than the minimum pedal force limit in 
S5.1.5.2(a) (2) where it appeared in the past. 

Standard No. 121 (49 CFR 571.121) was issued 
in February 1971 (36 FR 3817, February 27, 
1971) and has also been amended numerous times 
since issuance. Several amendments have oc- 
curred since the most recent publication of the 
standard in its entirety. For the reasons cited 
with regard to Standard No. 105-75, the agency 
herewith publishes the standard in its entirety. 
Interested persons are advised that three pro- 
posals to amend the standard are outstanding 
(40 FR 45200, October 1, 1975) (40 FR 56920, 
December 5, 1975) (41 FR 20706, May 20, 1976) 
and that amendments to the text of the standard 
may be made in the future. 

It has also been noted that a clarification could 
be made to the language of S3 of the standard 
that excludes luitil September 1, 1977, vehicles 
that combine with other vehicles to form auto 
transporters. The temporary exclusion was 
added to the standard in January 1975 (40 FR 
1246, January 7, 1975). To make the effect of 
that action more clear, the language in the second 
sentence of the text "or to any vehicle which" is 
changed in this republication to read "or that." 
This modification of the language has no effect 
on the requirements of this standard and notice 
and opportunity to comment are thei'efore found 
to be unnecessary. 

In consideration of the foregoing, Standard 
No. 105-75 (49 CFR 571.105-75) and Standard 
No. 121 (49 CFR 571.121) are republished to 
read as set forth below. 



PART 571; S 105-75— PRE 47 



Effective: July 19, 1976 

(Sec. 103, 119, Pub. L. 89-563, 80 Stat. 718 Robert L. Carter 

(15 U.S.C. 1392, 1407) ; delegations of authority Associate Administrator 

at 49 CFR 1.50 and 49 CFR 501.8.) Motor Vehicle Programs 

Issued on June 30, 1976. 41 p.R. 29696 

July 19, 1976 



PART 571; S 105-75— PRE 48 



Effective: July 19, 1976 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 

Hydraulic Brake Systems 
(Docket Nos. 75-7; 75-16; Notices 3, 9) 



This notice republishes in their entirely Stand- 
ard No. 105-75, Hydraulic Brake Systems^ and 
Standard No. 121, Air Brake Systems, because 
the number and complexity of recent amendments 
to these standards may have created confusion 
for some interested persons. 

Standard No. 105-75 (49 CFR 571.105-75) was 
issued September 1972 (37 FE 17970, September 
2, 1972) and has been amended numerous times 
since issuance. Although an up-to-date and com- 
plete text of the standard appears each year in 
the republished Code of Federal Regulations, 
several complex amendments have been made to 
the standard in the past year that are not re- 
flected in the most recent up-to-date text. To 
assist interested persons who must be certain of 
the text's provisions, the agency herewith pub- 
lishes the standard in its entirety. Interested 
persons are advised that amendments of Stand- 
ard No. 105-75 may occur in the future, although 
no proposals are outstanding at this time. 

In a related matter, General Motors Corpora- 
tion has brought to the agency's attention an 
inadvertent deletion of one sentence from one 
section of Standard No. 105-75. A statement 
was added to the text of S5.1.5.2(a) (2) to per- 
mit an interim increase in permissible control 
force for the fifth wet recovery stop (40 FR 
24525, June 9, 1975). Inadvertently, this sen- 
tence was deleted from S5.1.5.2(a) (2) in a sub- 
sequent rulemaldng action (40 FR 42872, 
September 17, 1975), although the preamble to 
the notice made clear that "The new wording in 
no way modifies the meaning of S5.1.4(a) (2) 
and S5.1.5.2(a) (2)." To correct this omission, 
the sentence appears in this publication. It has 



been moved to S5.1.5.2(a) (1) because it concerns 
the maximum pedal force limit in that section, 
rather than the minimum pedal force limit in 
S5.1.5.2(a) (2) where it appeared in the past. 

Standard No. 121 (49 CFR 571.121) was issued 
in February 1971 (36 FR 3817, February 27, 
1971 ) and has also been amended numerous times 
since issuance. Several amendments have oc- 
curred since the most recent publication of the 
standard in its entirety. For the reasons cited 
with regard to Standard No. 105-75, the agency 
herewith publishes the standard in its entirety. 
Interested persons are advised that three pro- 
posals to amend the standard are outstanding 
(40 FR 45200, October 1, 1975) (40 FR 56920, 
December 5, 1975) (41 FR 20706, May 20, 1976) 
and that amendments to the text of the standard 
may be made in the future. 

It has also been noted that a clarification could 
be made to the language of S3 of the standard 
that excludes until September 1, 1977, vehicles 
that combine with other vehicles to form auto 
transporters. The temporary exclusion was 
added to the standard in January 1975 (40 FR 
1246, January 7, 1975). To make the effect of 
that action more clear, the language in the second 
sentence of the text "or to any vehicle which" is 
changed in this republication to read "or that." 
This modification of the language has no effect 
on the requirements of this standard and notice 
and opportunity to comment are therefore found 
to be unnecessary. 

In consideration of the foregoing. Standard 
No. 105-75 (49 CFR 571.105-75) and Standard 
No. 121 (49 CFR 571.121) are republished to 
read as set forth below. 



PART 571; S 105-75— PRE 47 



Effecllva: July 19, 1976 

(Sec. 103, 119, Pub. L. 89-563, 80 Stat. 718 Kobert L. Carter 

(15 U.S.C. 1392, 1407) ; delegations of authority Associate Administrator 

at 49 CFR 1.50 and 49 CFR 501.8.) Motor Veliicle Programs 

Issued on June 30, 1976. 41 F.R. 29696 

July 19, 1976 



PART 571; S 105-75— PRE 48 



Effactiv*: August 26, 1976 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 

Hydraulic Brake Systems 

(Docket No. 73-03; Notice 7); (Docket No. 73-20; Notice 10); 

(Docket No. 73-34; Notice 4); (Docket No. 75-02; Notice 3); 

(Docket No. 75-03; Notice 5); (Docket No. 75-07; Notice 3); 

(Docket No. 75-24; Notice 3) 



This notice announces that the effective dates 
of the redefinition of "school bus" and of six 
Federal motor vehicle safety standards as they 
apply to school buses are changed to April 1, 
1977, from the previously established effective 
dates. This notice also makes a minor amend- 
ment to Standard No. 220, School Bus Rollover 
Protection^ and adds a figure to Standard No. 
221, School Bus Body Joint Strength. 

The Motor Vehicle and Schoolbus Safety 
Amendments of 1974 (the Act) mandated the 
issuance of Federal motor vehicle safety stand- 
ards for several aspects of school bus perform- 
ance, Pub. L. 93-492, §202 (15 U.S.C. §1392 
(i) (1) (A)). These amendments included a defi- 
nition of school bus that necessitated a revision 
of the existing definition used by the NHTSA 
in establishing safety requirements. The Act 
also specified that the new requirements "apply 
to each schoolbus and item of schoolbus equip- 
ment which is manufactured ... on or after the 
expiration of the 9-month period which begins 
on the date of promulgation of such safety 
standards." (15 U.S.C. § 1392(i) (1) (B) ). 

Pursuant to the Act, amendments were made 
to the following standards : Standard No. 301-75, 
Fuel System Integrity (49 CFR 571.301-75), 
effective July 15, 1976, for school buses not al- 
ready coverefl by the standard (40 FR 483521, 
October 15, 1975) ; Standard No. 105-75, Hy- 
draulic Brake Systems (49 CFR 571.105-75), ef- 
fective October 12, 1976 (41 FR 2391, January 
16, 1976) ; and Standard No. 217, Bus Window 
Retention and Release (49 CFR 571.217), effec- 



tive for school buses on October 26, 1976 (41 FR 
3871, January 27, 1976). 

In addition, the following new standards were 
added to Part 571 of Title 49 of the Code of 
Federal Regulations, effective October 26, 1976: 
Standard No. 220, School Bus Rollover Protec- 
tion (41 FR 3874, January 27, 1976) ; Standard 
No. 221, School Bus Body Joint Strength (41 
FR 3872, January 26, 1976) ; and Standard No. 
222, School Bus Passenger Seating and Crash 
Protection (41 FR 4016, January 28, 1976). Also, 
the existing definition of "school bus" was 
amended, effective October 27, 1976, in line with 
the date set by the Act for issuance of the stand- 
ards. 

The Act was recently amended by Public Law 
94-346 (July 8, 1976) to change the effective 
dates of the school bus standards to April 1, 
1977 (15 U.S.C. §1392(i)(l)(B)). This notice 
is intended to advise interested persons of these 
changes of effective dates. In the case of Stand- 
ard No. 301-75, the change of effective date is 
reflected in a conforming amendment to S5.4 of 
that standard. A similar amendment is made in 
S3 of Standard No. 105-75. 

The agency concludes that the October 27, 
1976, effective date for the redefinition of "school 
bus" should be postponed to April 1, 1977, to 
conform to the new effective dates for the up- 
coming requirements. If this were not done, the 
new classes of school buses would be required to 
meet existing standards that apply to school 
buses (e.g.. Standard No. 108 (49 CFR 571.108) ) 
before being required to meet the new standards. 
This would result in two stages of compliance, 



PART 571; S 105-75— PRE 49 



Effective: August 26, 1976 



and would complicate the redesign efforts that 
Congress sought to relieve. 

This notice also amends Standard No. 220 in 
response to an interpretation request by Blue 
Bird Body Company, and Sheller-Globe Cor- 
poration's petition for reconsideration of the 
standard. Both companies request confirmation 
that the standard's requirement to operate emer- 
gency exits during the application of force to the 
vehicle roof (S4(b)) does not apply to roof 
exits which are covered by the force application 
plate. The agency did not intend to require the 
operation of roof exits while the force applica- 
tion plate is in place on the vehicle. Accordingly, 
an appropriate amendment has been made to 
S4(b) of the standard. 

With regard to Standard No. 220, Sheller- 
Globe also requested confirmation that, in testing 
its school buses that have a gross vehicle weight 
rating (GVIVR) of 10,000 pounds or less, it may 
test with a force application plate with dimen- 
sions other than those specified in the standard. 
The standard does not prohibit a manufacturer 
from using a different dimension from that speci- 
fied, in view of the NHTSA's expressed position 
on the legal effect of its regulations. To certify 
compliance, a manufacturer is free to choose any 
means, in the exercise of due care, to show that 
a vehicle (or item of motor vehicle equipment) 
would comply if tested by the NHTSA as speci- 
fied in the standard. Thus the force application 
plate used by the NHTSA need not be dupli- 
cated by each manufacturer or compliance test 
facility. Sheller-Globe, for example, is free to 
use a force application plate of any width as 
long as it can certify its vehicle would comply 
if tested by the NHTSA according to the stand- 
ard. 

In a separate area, the agency corrects the in- 
advertent omission of an illustration from 
Standard No. 221 as it was issued January 26, 
1976 (41 -FR 3872). The figure does not differ 
from that proposed and, in that form, it received 
no adverse comment. 

In accordance with recently-enunciated De- 
partment of Transportation policy encouraging 



adequate analysis of the consequences of regula- ' 
tory action (41 FR 16200, April 16, 1976), the 
agency herewith summarizes its evaluation of the 
economic and other consequences of this action 1 
on the public and private sectors, including pos- 
sible loss of safety benefits. The changes in I 
effective dates for the school bus standards are \ 
not evaluated because they were accomplished by 
law and not by regulatory action. 

The change of effective date for the redefini- 
tion of "school bus" will result in savings to 
manufacturers who will not be required to meet 
existing school bus standards between October 
27, 1976, and April 1, 1977. The agency calcu- 
lates that the only standard that would not be 
met would be the requirement in Standard No. 
108 for school bus marker lamps. In view of the 
agency's existing provision for the markings of 
eight school buses in Pupil Transportation 
Standard No. 17 (23 CFR 1204), it is concluded 
that the absence of this equipment until April 1, 
1977, will not have a significant adverse impact 
on safety. 

The interpretative amendment of Standard No. d 

220 and the addition of a figure to Standard No. " 

221 are not expected to affect the manufacture or 
operation of school buses. 

In consideration of the foregoing, Part 571 of 
Title 49 of the Code of Federal Regulations is 
amended. . . . 

Effective dates: 

1. Because the listed amendments do not im- 
pose additional requirements of any person, the 
National Highway Traffic Safety Administration 
finds that an immediate effective date of August 
20, 1976 is in the public interest. 

2. The effective date of the redefinition of 
"school bus" in 49 CFR Part 571.3 that was 
published in the issue of December 31, 1976 (40 
FR 60033) is changed to April 1, 1977. 

3. The effective dates of Standard Nos. 105-75, 
217, 301-75, 220, 221, and 222 (as they apply to 
school buses) are April 1, 1977, in accordance 
with Public Law 94-346. 

(Sec. 103, 119, Pub. L. 89-563, 80 Stat. 718 
(15 U.S.C. 1392, 1407); Pub. L. 94-346, Stat. j 



PART 571; S 105-75— PRE 50 



Effecliva: August 26, 1976 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 105-75 

Hydraulic Brake Systems 

(Docket No. 73-03; Notice 7); (Docket No. 73-20; Notice 10); 

(Docket No. 73-34; Notice 4); (Docket No. 75-02; Notice 3); 

(Docket No. 75-03; Notice 5); (Docket No. 75-07; Notice 3); 

(Docket No. 75-24; Notice 3) 



This notice announces that the eflFective dates 
of the redefinition of "school bus" and of six 
Federal motor vehicle safety standards as they 
apply to school buses are changed to April 1, 
1977, from the previously established effective 
dates. This notice also makes a minor amend- 
ment to Standard No. 220, School Bus Rollover 
Protection, and adds a figure to Standard No. 
221, School Bv^ Body Joint Strength. 

The Motor Vehicle and Schoolbus Safety 
Amendments of 1974 (the Act) mandated the 
issuance of Federal motor vehicle safety stand- 
ards for several aspects of school bus perform- 
ance, Pub. L. 93^92, §202 (15 U.S.C. §1392 
(i) (1) (A) ). These amendments included a defi- 
nition of school bus that necessitated a revision 
of the existing definition used by the NHTSA 
in establishing safety requirements. The Act 
also specified that the new requirements "apply 
to each schoolbus and item of schoolbus equip- 
ment which is manufactured ... on or after the 
expiration of the 9-month period which begins 
on the date of promulgation of such safety 
standards." (15 U.S.C. § 1392(i) (1) (B) ). 

Pursuant to the Act, amendments were made 
to the following standards : Standard No. 301-75, 
Fitsl System Integrity (49 CFR 571.301-75), 
effective July 15, 1976, for school buses not al- 
ready covered by the standard (40 FR 483521, 
October 15, 1975) ; Standard No. 105-75, Hy- 
draulic Brake Systems (49 CFR 571.105-75), ef- 
fective October 12, 1976 (41 FR 2391, January 
16, 1976) ; and Standard No. 217, Bus Window 
Retention and Release (49 CFR 571.217), effec- 



tive for school buses on October 26, 1976 (41 FR 
3871, January 27, 1976). 

In addition, the following new standards were 
added to Part 571 of Title 49 of the Code of 
Federal Regulations, effective October 26, 1976: 
Standard No. 220, School Bus Rollover Protec- 
tion (41 FR 3874, January 27, 1976) ; Standard 
No. 221, School Bus Body Joint Strength (41 
FR 3872, January 26, 1976) ; and Standard No. 
222, School Bus Passenger Seating and Crash 
Protection (41 FR 4016, January 28, 1976). Also, 
the existing definition of "school bus" was 
amended, effective October 27, 1976, in line with 
the date set by the Act for issuance of the stand- 
ards. 

The Act was recently amended by Public Law 
94-346 (July 8, 1976) to change the effective 
dates of the school bus standards to April 1, 
1977 (15 U.S.C. §1392(i)(l)(B)). This notice 
is intended to advise interested persons of these 
changes of effective dates. In the case of Stand- 
ard No. 301-75, the change of effective date is 
reflected in a conforming amendment to S5.4 of 
that standard. A similar amendment is made in 
S3 of Standard No. 105-75. 

The agency concludes that the October 27, 
1976, effective date for the redefinition of "school 
bus" should be postponed to April 1, 1977, to 
conform to the new effective dates for the up- 
coming requirements. If this were not done, the 
new classes of school buses would be required to 
meet existing standards that apply to school 
buses (e.g.. Standard No. 108 (49 CFR 571.108) ) 
before being required to meet the new standards. 
This would result in two stages of compliance, 



PART 571; S 105-75— PRE 49 



Effective: August 36, 1976 



and would complicate the redesign efforts that 
Congress sought to relieve. 

This notice also amends Standard No. 220 in 
response to an interpretation request by Blue 
Bird Body Company, and Sheller-Globe Cor- 
poration's petition for reconsideration of the 
standard. Both companies request confirmation 
that the standard's requirement to operate emer- 
gency exits during the application of force to the 
vehicle roof (S4(b)) does not apply to roof 
exits which are covered by the force application 
plate. The agency did not intend to require the 
operation of roof exits while the force applica- 
tion plate is in place on the vehicle. Accordingly, 
an appropriate amendment has been made to 
S4(b) of the standard. 

With regard to Standard No. 220, Sheller- 
Globe also requested confirmation that, in testing 
its school buses that have a gross vehicle weight 
rating (GVWR) of 10,000 pounds or less, it may 
test with a force application plate with dimen- 
sions other than those specified in the standard. 
The standard does not prohibit a manufacturer 
from using a different dimension from that speci- 
fied, in view of the NHTSA's expressed position 
on the legal effect of its regulations. To certify 
compliance, a manufacturer is free to choose any 
means, in the exercise of due care, to show that 
a vehicle (or item of motor vehicle equipment) 
would comply if tested by the NHTSA as speci- 
fied in the standard. Thus the force application 
plate used by the NHTSA need not be dupli- 
cated by each manufacturer or compliance test 
facility. Sheller-Globe, for example, is free to 
use a force application plate of any width as 
long as it can certify its vehicle would comply 
if tested by the NHTSA according to the stand- 
ard. 

In a separate area, the agency corrects the in- 
advertent omission of an illustration from 
Standard No. 221 as it was issued January 26, 
1976 (41 FR 3872). The figure does not differ 
from that proposed and, in that form, it received 
no adverse comment. 

In accordance with recently-enunciated De- 
partment of Transportation policy encouraging 



adequate analysis of the consequences of regula- 
tory action (41 FR 16200, April 16, 1976), the 
agency herewith summarizes its evaluation of the 
economic and other consequences of this action 
on the public and private sectors, including pos- 
sible loss of safety benefits. The changes in 
effective dates for the school bus standards are 
not evaluated because they were accomplished by 
law and not by regulatory action. 

The change of effective date for the redefini- 
tion of "school bus" will result in savings to 
manufacturers who will not be required to meet 
existing school bus standards between October 
27, 1976, and April 1, 1977. The agency calcu- 
lates that the only standard that would not be 
met would be the requirement in Standard No. 
108 for school bus marker lamps. In view of the 
agency's existing provision for the markings of 
eight school buses in Pupil Transportation 
Standard No. 17 (23 CFR 1204), it is concluded 
that the absence of this equipment until April 1, 
1977, will not have a significant adverse impact 
on safety. 

The interpretative amendment of Standard No. 

220 and the addition of a figure to Standard No. 

221 are not expected to affect the manufacture or 
operation of school buses. 

In consideration of the foregoing. Part 571 of 
Title 49 of the Code of Federal Regulations is 
amended. . . . 

Effective dates: 

1. Because the listed amendments do not im- 
pose additional requirements of any person, the 
National Highway Traffic Safety Administration 
finds that an immediate effective date of August 
20, 1976 is in the public interest. 

2. The effective date of the redefinition of 
"school bus" in 49 CFR Part 571.3 that was 
published in the issue of December 31, 1976 (40 
FR 60033) is changed to April 1, 1977. 

3. The effective dates of Standard Nos. 105-75, 
217, 301-75, 220, 221, and 222 (as they apply to 
school buses) are April 1, 1977, in accordance 
with Public Law 94-346. 

(Sec. 103, 119, Pub. L. 89-563, 80 Stat. 718 
(15 U.S.C. 1392, 1407); Pub. L. 94-346, Stat. 



PART 571; S 105-75— PRE 50 



Effectrve: Auguil 26, 1976 

(15 U.S.C. §1392(i)(l)(B)); delegation of John W. Snow 

authority at 49 CFR 1.50.) Administrator 

Issued on August 17, 1976. 41 p jj 3^026 

August 26, 1976 



PAET 571; S 105-75— PEE 51-52 



Effective: August 26, 1976 



(15 U.S.C. §1392(i)(l)(B)); delegation of John W. Snow 

authority at 49 CFR 1.50.) Administrator 

Issued on August 17, 1976. 41 F.R. 36026 

August 26, 1976 



PART 571; S 105-75— PRE 51-52 



PREAMBLE TO FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 105-83 



Hydraulic Brake Systems 
(Docket No. 70-27; Notice 20) 



ACTION: Final rule. 



SUIMMARY: Tliis notice amends Standard 105, 
Hydraulic Brake Systems. The standard current- 
ly applies to passenger cars and school buses. Its 
applicability is extended on a general basis (with 
some modifications) to trucks, all types of buses, 
and multipurpose passenger vehicles (MPV's) 
with a gross vehicle weight rating (GVWR) of 
10,000 lbs. or less. Several requirements are also 
extended to trucks, buses and MPV's with a 
GVWR greater than 10,000 lbs. In addition, the 
standard's requirements for school buses are 
upgraded. 

DATES: The effective date of this amendment is 
September 1, 1983. 

ADDRESSES: Petitions for reconsideration should 
refer to the docket number and be submitted to: 
Docket Section, Room 5108, 400 Seventh Street, 
S.W., Washington, D.C. 20590. 

FOR FURTHER INFORMATION CONTACT: 

Mr. George L. Parker, Office of Vehicle 
Safety Standards, National Highway Traffic 
Safety Administration, 400 Seventh Street 
S.W„ Washington D.C. 20590 
(202-426-2720) 

SUPPLEMENTARY INFORMATION: Standard 105, 
Hydraulic Brake Systems, currently applies to 
passenger cars and school buses. This notice ex- 
tends its applicability on a general basis (with 
some modifications) to trucks, all types of buses, 
and multipurpose passenger vehicles (MPV's) 
with a gross vehicle weight rating (GVWR) of 
10,000 lbs. or less. Several requirements are also 
extended to trucks, buses and MPV's with a 
GVWR greater than 10,000 lbs. In addition, the 



standard's requirements for school buses are 
upgraded. 

This final rule was preceded by a notice propos- 
ing the extension of Standard 105 in October 1979 
(44 FR 60113). Private citizens, safety organiza- 
tions, manufacturers, and manufacturer trade 
associations have submitted comments on the 
proposal. The NHTSA has considered all of those 
comments and the most significant ones are dis- 
cussed below. 

The agency made two significant modifications 
in the proposed standard's requirements as a 
result of the comments. As will be explained 
below, the agency determined that third effec- 
tiveness requirements should not be applicable to 
vehicles, other than school buses, with a GVWR 
of 8,000 to 10,000 lbs. Also, the agency deter- 
mined that fourth effectiveness stopping distance 
requirements for vehicles with a GVWR of 8,000 
to 10,000 lbs., as well as spike stop check stopping 
distance requirements for those vehicles, should 
be slightly relaxed. 

The changes in the standard's requirements 
were made to give manufacturers additional 
leeway in balancing the performance of their 
vehicles' braking systems for both fully loaded 
and lightly loaded conditions and to ensure that 
the requirements would not result in unduly 
burdensome certification responsibilities being 
imposed on final stage manufacturers. 

A slight change was also made in the 
standard's definition of "lightly loaded vehicle 
weight" to permit the use of additional in- 
strumentation. 

Also in response to the comments, the agency 
determined that a longer period of leadtime 
should be provided. The effective date of the re- 
quirements is September 1, 1983, which gives a 
leadtime of more than two years. 

Many comments were received in support of 



PART 571; S 105-83-PRE 53 



extending Standard 105 to to apply to trucks, all 
types of buses, and MPV's. General Motors, 
Chrysler and American Motors/Jeep all stated 
that they support the adoption of requirements 
for hydraulic braked trucks, buses and MPV's, 
though all three companies requested some 
modifications in the standard as proposed. 
Wagner Electric stated that it is commendable 
that efforts are being made to improve the safety 
of the highways and that it can see the benefits 
that may accrue when more varieties of highway 
vehicles have been brought under the control of 
the appropriate minimum braking standard. 

Both Ford and the Japan Automobile Manufac- 
turers Association stated that they are not op- 
posed to the application of braking performance 
requirements to vehicles in addition to passenger 
cars and school buses. The Japan Automobile 
Manufacturers Association added that, from the 
viewpoint of safety, it thought this application 
should be promoted. 

The National Transportation Safety Board 
stated that it supported the action, noting that by 
reducing the current disparity between the brak- 
ing capability of passenger cars and many trucks 
and vans, motor vehicle accidents should be 
reduced. The Board also stated its support for the 
requirements upgrading the performance re- 
quirements for school buses. 

While the General Accounting Office of the 
United States did not specifically comment on 
this rulemaking, a report to the United States 
Congress by the Comptroller General issued in 
1978 called for, among other things, expeditious 
rulemaking on light truck braking performance. 
See Report to Congress by the Comptroller 
General of the United States, Unwarranted 
Delays by the Department of Transportation to 
Improve Light Truck Safety, July 6, 1978. 

The Center for Auto Safety stated that exten- 
sion of the standard is long overdue and is fully 
supported by the large number of consumer com- 
plaints that the Center received each year on in- 
adequate brakes on light trucks, vans and MPV's. 

Effectiveness Requirements 

Comments received on the proposal's effec- 
tiveness requirements for service brake systems 
primarily dealt with the third and fourth effec- 
tiveness test stopping distances for vehicles with 
a GVWR of 8,000 to 10,000 lbs. Several comments 



stated that the stopping distance requirements 
that were proposed were too stringent. 

The fourth effectiveness test is an effec- 
tiveness test of the braking system which is con- 
ducted after the fade tests and while the vehicle 
is fully loaded. Because it comes after the fade 
tests, during which some deterioration of the 
brakes may occur, the fourth effectiveness test 
was considered by several commenters to be the 
most stringent of the fully loaded effectiveness 
tests. Generally discussed along with the fourth 
effectiveness test were the spike stop check stop- 
ping distance requirements. These requirements 
represent an abbreviated effectiveness test with 
the same stopping distance requirements as the 
fourth effectiveness test, which is conducted 
after the spike stops (which follow the fourth ef- 
fectiveness test). Because the commenters ad- 
dressed these tests together and because the 
stopping distance requirements are the same for 
the two tests, the discussion of these re- 
quirements will subsume the spike stop check 
stopping distance requirements into considera- 
tion of the fourth effectiveness stopping distance 
requirements. 

According to the commenters, brakes which 
are powerful enough to meet the fourth effec- 
tiveness (fully loaded) stopping distance re- 
quirements for vehicles in that weight class 
would be prone to lockup in the lightly loaded con- 
dition. If lockup occurred in the lightly loaded 
condition, the vehicles would be unable to meet 
the third effectiveness (lightly loaded) stopping 
distance requirements. Several comments stated 
that manufacturers would find it necessary to 
develop anti-lock or similar devices in order to 
meet the requirements as proposed. 

Other comments on the third and fourth effec- 
tiveness requirements for this class of vehicles 
focused on possible deleterious effects that the 
requirements might have on final stage manufac- 
turers and the market which they serve. (A "final 
stage manufacturer" is a manufacturer which 
typically purchases an incomplete vehicle which 
usually consists only of a chassis, suspension, 
power train, brakes and perhaps an occupant 
compartment from an incomplete vehicle manu- 
facturer such as Ford, General Motors or 
Chrysler and completes the vehicle by adding a 
body or work-performing equipment). 

Any final stage manufacturer that does not 



PART 571; S 105-83-PRE 54 



PREAMBLE TO FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 105-83 

Hydraulic Brake Systems 
(Docket No. 70-27; Notice 20) 



ACTION: Final rule. 

SUMMARY: This notice amends Standard 105, 
Hydraulic Brake Systems. The standard current- 
ly applies to passenger cars and school buses. Its 
applicability is extended on a general basis (with 
some modifications) to trucks, all types of buses, 
and multipurpose passenger vehicles (MPV's) 
with a gross vehicle weight rating (GVWR) of 
10,000 lbs. or less. Several requirements are also 
extended to trucks, buses and MPV's with a 
GVWR greater than 10,000 lbs. In addition, the 
standard's requirements for school buses are 
upgraded. 

DATES: The effective date of this amendment is 
September 1, 1983. 

ADDRESSES: Petitions for reconsideration should 
refer to the docket number and be submitted to: 
Docket Section, Room 5108, 400 Seventh Street, 
S.W., Washington, D.C. 20590. 

FOR FURTHER INFORMATION CONTACT: 
Mr. George L. Parker, Office of Vehicle 
Safety Standards, National Highway Traffic 
Safety Administration, 400 Seventh Street 
S.W.. Washington D.C. 20590 
(202426-2720) 

SUPPLEMENTARY INFORMATION: Standard 105, 
Hydraulic Brake Systems, currently applies to 
passenger cars and school buses. This notice ex- 
tends its applicability on a general basis (with 
some modifications) to trucks, all types of buses, 
and multipurpose passenger vehicles (MPV's) 
with a gross vehicle weight rating (GVWR) of 
10,000 lbs. or less. Several requirements are also 
extended to trucks, buses and MPV's with a 
GVWR greater than 10,000 lbs. In addition, the 



standard's requirements for school buses are 
upgraded. 

This final rule was preceded by a notice propos- 
ing the extension of Standard 105 in October 1979 
(44 FR 60113). Private citizens, safety organiza- 
tions, manufacturers, and manufacturer trade 
associations have submitted comments on the 
proposal. The NHTSA has considered all of those 
comments and the most significant ones are dis- 
cussed below. 

The agency made two significant modifications 
in the proposed standard's requirements as a 
result of the comments. As will be explained 
below, the agency determined that third effec- 
tiveness requirements should not be applicable to 
vehicles, other than school buses, with a GVWR 
of 8,000 to 10,000 lbs. Also, the agency deter- 
mined that fourth effectiveness stopping distance 
requirements for vehicles with a GVWR of 8,000 
to 10,000 lbs., as well as spike stop check stopping 
distance requirements for those vehicles, should 
be slightly relaxed. 

The changes in the standard's requirements 
were made to give manufacturers additional 
leeway in balancing the performance of their 
vehicles' braking systems for both fully loaded 
and lightly loaded conditions and to ensure that 
the requirements would not result in unduly 
burdensome certification responsibilities being 
imposed on final stage manufacturers. 

A slight change was also made in the 
standard's definition of "lightly loaded vehicle 
weight" to permit the use of additional in- 
strumentation. 

Also in response to the comments, the agency 
determined that a longer period of leadtime 
should be provided. The effective date of the re- 
quirements is September 1, 1983, which gives a 
leadtime of more than two years. 

Many comments were received in support of 



PART 571; S 105-83-PRE 53 



extending Standard 105 to to apply to trucks, all 
types of buses, and MPV's. General Motors, 
Chrysler and American Motors/Jeep all stated 
that they support the adoption of requirements 
for hydraulic braked trucks, buses and MPV's, 
though all three companies requested some 
modifications in the standard as proposed. 
Wagner Electric stated that it is commendable 
that efforts are being made to improve the safety 
of the highways and that it can see the benefits 
that may accrue when more varieties of highway 
vehicles have been brought under the control of 
the appropriate minimum braking standard. 

Both Ford and the Japan Automobile Manufac- 
turers Association stated that they are not op- 
posed to the application of braking performance 
requirements to vehicles in addition to passenger 
cars and school buses. The Japan Automobile 
Manufacturers Association added that, from the 
viewpoint of safety, it thought this application 
should be promoted. 

The National Transportation Safety Board 
stated that it supported the action, noting that by 
reducing the current disparity between the brak- 
ing capability of passenger cars and many trucks 
and vans, motor vehicle accidents should be 
reduced. The Board also stated its support for the 
requirements upgrading the performance re- 
quirements for school buses. 

While the General Accounting Office of the 
United States did not specifically comment on 
this rulemaking, a report to the United States 
Congress by the Comptroller General issued in 
1978 called for, among other things, expeditious 
rulemaking on light truck braking performance. 
See Report to Congress by the Comptroller 
General of the United States, Unwarranted 
Delays by the Department of Transportation to 
Improve Light Truck Safety, July 6, 1978. 

The Center for Auto Safety stated that exten- 
sion of the standard is long overdue and is fully 
supported by the large number of consumer com- 
plaints that the Center received each year on in- 
adequate brakes on light trucks, vans and MPV's. 

Effectiveness Requirements 

Comments received on the proposal's effec- 
tiveness requirements for service brake systems 
primarily dealt with the third and fourth effec- 
tiveness test stopping distances for vehicles with 
a GVWR of 8,000 to 10,000 lbs. Several comments 



stated that the stopping distance requirements 
that were proposed were too stringent. 

The fourth effectiveness test is an effec- 
tiveness test of the braking system which is con- 
ducted after the fade tests and while the vehicle 
is fully loaded. Because it comes after the fade 
tests, during which some deterioration of the 
brakes may occur, the fourth effectiveness test 
was considered by several commenters to be the 
most stringent of the fully loaded effectiveness 
tests. Generally discussed along with the fourth 
effectiveness test were the spike stop check stop- 
ping distance requirements. These requirements 
represent an abbreviated effectiveness test with 
the same stopping distance requirements as the 
fourth effectiveness test, which is conducted 
after the spike stops (which follow the fourth ef- 
fectiveness test). Because the commenters ad- 
dressed these tests together and because the 
stopping distance requirements are the same for 
the two tests, the discussion of these re- 
quirements will subsume the spike stop check 
stopping distance requirements into considera- 
tion of the fourth effectiveness stopping distance 
requirements. 

According to the commenters, brakes which 
are powerful enough to meet the fourth effec- 
tiveness (fully loaded) stopping distance re- 
quirements for vehicles in that weight class 
would be prone to lockup in the lightly loaded con- 
dition. If lockup occurred in the lightly loaded 
condition, the vehicles would be unable to meet 
the third effectiveness (lightly loaded) stopping 
distance requirements. Several comments stated 
that manufacturers would find it necessary to 
develop anti-lock or similar devices in order to 
meet the requirements as proposed. 

Other comments on the third and fourth effec- 
tiveness requirements for this class of vehicles 
focused on possible deleterious effects that the 
requirements might have on final stage manufac- 
turers and the market which they serve. (A "final 
stage manufacturer" is a manufacturer which 
typically purchases an incomplete vehicle which 
usually consists only of a chassis, suspension, 
power train, brakes and perhaps an occupant 
compartment from an incomplete vehicle manu- 
facturer such as Ford, General Motors or 
Chrysler and completes the vehicle by adding a 
body or work-performing equipment). 

Any final stage manufacturer that does not 



PART 571; S 105-83-PRE 54 



complete a vehicle in accordance with conditions 
established by the incomplete vehicle manufac- 
turer must recertify that the completed vehicle 
complies with applicable safety standards based 
upon its own information, analysis, or tests. 
Several commenters were concerned that final 
stage manufacturers would not be able to meet 
those conditions and thus would be required to 
engage in extensive testing of their vehicles. Ac- 
cording to those commenters, extensive testing is 
not feasible for final stage manufacturers as they 
are often small manufacturers that produce only 
limited numbers of a variety of specialty vehicles. 

Changes suggested by the commenters varied, 
depending upon whether they were addressing 
the requirements from the point of view of the 
large manufacturers (i.e., the incomplete vehicle 
manufacturers) or the final stage manufacturers. 
General Motors, for example, stated that it could 
meet the longest of a range of stopping distances 
proposed for the third effectiveness test if fourth 
effectiveness test stopping distances were ex- 
tended by 10 percent. Comments received from 
Ford and Chrysler were similar, with Ford asking 
for a relatively minor increase in third effec- 
tiveness stopping distances and a 10 percent in- 
crease in fourth effectiveness stopping distances, 
while Chrysler requested a 16 percent increase in 
stopping distances for fourth effectiveness tests. 

Those commenters primarily concerned with 
final stage manufacturer certification difficulties 
suggested various approaches, including not 
extending Standard 105 at this time or only ex- 
tending it to vehicles with a GVWR under 8,000 
lbs. Other approaches suggested by those com- 
menters include applying different test re- 
quirements to final stage manufacturers, so long 
as the braking systems on their vehicles are used 
on similar vehicles, requiring incomplete vehicle 
manufacturers to give additional information to 
final stage manufacturers to help them make 
engineering judgments about the effect changes 
in the center of gravity will have on a vehicle's 
braking ability, and providing a longer period of 
leadtime to final stage manufacturers than other 
manufacturers. 

The latter approach was suggested because 
some final stage manufacturers were concerned 
that incomplete vehicle manufacturers would not 
provide information about new conditions estab- 
lished as a result of the proposed requirements 



until just before the time of model introduc- 
tion. According to those comments, final stage 
manufacturers need to receive such information 
well in advance of the time of model introduction 
in order that they can design their vehicles in 
accordance with the conditions. 

The agency was aware of the braking design 
problems associated with trucks, buses and 
MPV's, including those particularly affecting 
vehicles over 8,000 lbs. GVWR, when it issued the 
proposal. The proposal explained that while 
trucks, buses and MPV's should ideally stop in as 
short a distance as passenger cars, since they 
share the same roads and traffic flow, there are 
certain differences between those vehicles which 
make accomplishing that goal more difficult for 
trucks, buses and MPV's. The primary dif- 
ferences are the greater loaded to empty-weight 
ratio of trucks, MPV's and buses, the higher 
center of gravity found in those vehicles (which 
results in greater dynamic weight transfer dur- 
ing braking), the greater variations in loaded and 
unloaded weight distribution that occur in those 
vehicles and the lower traction capabilities of 
truck tires. Because these factors make it difficult 
to design braking systems which provide the ap- 
propriate brake torque for each axle under all 
braking and load conditions, the agency proposed 
stopping distances that were slightly longer than 
those in effect for passenger cars. 

The notice also discussed the design problems 
particularly affecting trucks, buses and MPV's 
with a GVWR over 8,000 lbs. In order to stop in as 
short a distance as lighter vehicles, vehicles with 
GVWR of 8,000 lbs. or more require powerful rear 
brakes to meet fully loaded stopping distance re- 
quirements. When the vehicles are stopped in a 
lightly loaded condition, however, the powerful 
rear brakes can cause wheel-lockup and resulting 
vehicle instability. Because of these design prob- 
lems, the agency proposed ranges of slightly 
longer third effectiveness test stopping distances 
for vehicles with a GVWR of 8,000 to 10,000 lbs 
than for vehicles with lower GVWR. In proposing 
the requirements, the agency stated that it was 
its intention to avoid requiring manufacturers to 
develop anti-lock or similar devices for their 
vehicles. While such systems may be able to over- 
come these problems, there is no field-tested anti- 
lock system for hydraulic-braked vehicles that is 
commercially available at this time. 



PART 571; S 105-83-PRE 55 



The stopping distances proposed for the third 
and fourth effectiveness tests were based upon 
tests conducted by the agency on existing produc- 
tion vehicles and upon confidential brake develop- 
ment test data submitted by General Motors, Ford 
and Chrysler. Based upon its analysis of these data, 
the agency concluded that the proposed stopping 
distances for both the third and fourth effec- 
tiveness tests for vehicles with a G V WR of 8,000 to 
10,000 lbs., including vehicles with unusually high 
centers of gravity and with both short and long 
wheelbases (which typically are more difficult to 
design brakes for than other vehicles), could be 
met without anti-lock or similar devices. Instead, 
the requirements could be met by modifications to 
such vehicle components as brake linings, wheel 
cylinders, master cylinders, and combination 
valves. 

This conclusion does not, however, fully resolve 
the concerns raised about the requirements as 
they relate to final stage manufacturers. As noted 
above, final stage manufacturers, typically pur- 
chase incomplete vehicles from large manufac- 
turers and complete the vehicles, often for 
specialized needs. Since only a limited number of 
incomplete vehicle designs are available for pur- 
chase, a final stage manufacturer must use the 
same incomplete vehicle design for widely varying 
applications. A given incomplete vehicle design 
may be completed as a pickup, a recreational vehi- 
cle, or a high cube van. Diverse equipment may be 
added such as service cranes, lift gates, ladders, 
aerial devices, and snow plows. Assuming that a 
final stage manufacturer does not redesign the 
braking system for each different use, the braking 
system sold with the incomplete vehicle by its 
manufacturer must serve applications with widely 
varying centers of gravity (i.e., varying both ver- 
tically and horizontally). 

The agency estimates that a 10 percent rise in 
center of gravity location will lengthen the stop- 
ping distance of a typical vehicle by three percent 
if it is operating at the limit of tire traction for its 
rear wheels. Changes in horizontal center of grav- 
ity will also lengthen stopping distances in some in- 
stances. It follows that a vehicle which would 
barely meet the requirements of the proposed 
standard at the specific center of gravity for which 
it is designed, which would be the case for some 
vehicles with a GVWR of 8,000 to 10,000 lbs., would 
not be able to meet the requirements at centers 



of gravity widely varying from the design one. 

The agency agrees, after analysis of the com- 
ments received from final stage manufacturers, 
their trade associations, and incomplete vehicle 
manufacturers, that the increased center of gravi- 
ty limitations which might be established for some 
vehicles of 8,000 to 10,000 lbs. GVWR if the pro- 
posal were adopted would pose significant dif- 
ficulties for final stage manufacturers. (Some 
limitations are currently established by in- 
complete vehicle manufacturers in connection with 
their certification of Standards 212, 219, and 301.) 
In some instances, a final stage manufacturer 
would be unable to simply complete vehicles on the 
same incomplete vehicle that it is accustomed to 
using, as the center of gravity of the completed 
vehicles would not be within the center of gravity 
envelope specified by the incomplete vehicle 
manufacturer. 

The final stage manufacturer would be faced 
with buying the same incomplete vehicles as 
before and recertifying them and possibly rede- 
signing their braking systems. Since the sales of in- 
complete vehicles to final stage manufacturers are 
a very small percentage of the light truck sales of 
the incomplete vehicle manufacturers, the in- 
complete vehicle manufacturers are not likely to 
be willing to accommodate the final stage manufac- 
turers by making major modifications to the line of 
incomplete vehicles they offer for sale, such as pro- 
viding incomplete vehicles which are designed for 
a broader range of centers of gravity. The in- 
complete vehicle manufacturers have themselves 
indicated this reluctance in a number of rulemak- 
ings. 

The agency has dealt with the certification prob- 
lems of final stage manufacturers during other 
rulemaking proceedings. Since final stage manu- 
facturers are often very small companies, which 
produce limited numbers of speciality vehicles, 
they often have limited resources for redesign- 
ing their vehicles, testing their vehicles for compli- 
ance with applicable safety standards, or making 
engineering judgments about the effect changes in 
a vehicle's center of gravity will have on the vehi- 
cle's performance. Therefore, the agency has 
sought to limit, consistent with the needs of safety, 
the compliance burdens on final stage manufac- 
turers. 

For example, the agency established special pro- 
visions affording relief to final stage manufac- 



PART 571; S 105-83-PRE 56 



complete a vehicle in accordance with conditions 
established by the incomplete vehicle manufac- 
turer must recertify that the completed vehicle 
complies with applicable safety standards based 
upon its own information, analysis, or tests. 
Several commenters were concerned that final 
stage manufacturers would not be able to meet 
those conditions and thus would be required to 
engage in extensive testing of their vehicles. Ac- 
cording to those commenters, extensive testing is 
not feasible for final stage manufacturers as they 
are often small manufacturers that produce only 
limited numbers of a variety of specialty vehicles. 

Changes suggested by the commenters varied, 
depending upon whether they were addressing 
the requirements from the point of view of the 
large manufacturers (i.e., the incomplete vehicle 
manufacturers) or the final stage manufacturers. 
General Motors, for example, stated that it could 
meet the longest of a range of stopping distances 
proposed for the third effectiveness test if fourth 
effectiveness test stopping distances were ex- 
tended by 10 percent. Comments received from 
Ford and Chrysler were similar, with Ford asking 
for a relatively minor increase in third effec- 
tiveness stopping distances and a 10 percent in- 
crease in fourth effectiveness stopping distances, 
while Chrysler requested a 16 percent increase in 
stopping distances for fourth effectiveness tests. 

Those commenters primarily concerned with 
final stage manufacturer certification difficulties 
suggested various approaches, including not 
extending Standard 105 at this time or only ex- 
tending it to vehicles with a GVWR under 8,000 
lbs. Other approaches suggested by those com- 
menters include applying different test re- 
quirements to final stage manufacturers, so long 
as the braking systems on their vehicles are used 
on similar vehicles, requiring incomplete vehicle 
manufacturers to give additional information to 
final stage manufacturers to help them make 
engineering judgments about the effect changes 
in the center of gravity will have on a vehicle's 
braking ability, and providing a longer period of 
leadtime to final stage manufacturers than other 
manufacturers. 

The latter approach was suggested because 
some final stage manufacturers were concerned 
that incomplete vehicle manufacturers would not 
provide information about new conditions estab- 
lished as a result of the proposed requirements 



until just before the time of model introduc- 
tion. According to those comments, final stage 
manufacturers need to receive such information 
well in advance of the time of model introduction 
in order that they can design their vehicles in 
accordance with the conditions. 

The agency was aware of the braking design 
problems associated with trucks, buses and 
MPV's, including those particularly affecting 
vehicles over 8,000 lbs. GVWR, when it issued the 
proposal. The proposal explained that while 
trucks, buses and MPV's should ideally stop in as 
short a distance as passenger cars, since they 
share the same roads and traffic flow, there are 
certain differences between those vehicles which 
make accomplishing that goal more difficult for 
trucks, buses and MPV's. The primary dif- 
ferences are the greater loaded to empty-weight 
ratio of trucks, MPV's and buses, the higher 
center of gravity found in those vehicles (which 
results in greater dynamic weight transfer dur- 
ing braking), the greater variations in loaded and 
unloaded weight distribution that occur in those 
vehicles and the lower traction capabilities of 
truck tires. Because these factors make it difficult 
to design braking systems which provide the ap- 
propriate brake torque for each axle under all 
braking and load conditions, the agency proposed 
stopping distances that were slightly longer than 
those in effect for passenger cars. 

The notice also discussed the design problems 
particularly affecting trucks, buses and MPV's 
with a GVWR over 8,000 lbs. In order to stop in as 
short a distance as lighter vehicles, vehicles with 
GVWR of 8,000 lbs. or more require powerful rear 
brakes to meet fully loaded stopping distance re- 
quirements. When the vehicles are stopped in a 
lightly loaded condition, however, the powerful 
rear brakes can cause wheel-lockup and resulting 
vehicle instability. Because of these design prob- 
lems, the agency proposed ranges of slightly 
longer third effectiveness test stopping distances 
for vehicles with a GVWR of 8,000 to 10,000 lbs 
than for vehicles with lower GVWR. In proposing 
the requirements, the agency stated that it was 
its intention to avoid requiring manufacturers to 
develop anti-lock or similar devices for their 
vehicles. While such systems may be able to over- 
come these problems, there is no field-tested anti- 
lock system for hydraulic-braked vehicles that is 
commercially available at this time. 



PART 571; S 105-83-PRE 55 



The stopping distances proposed for the third 
and fourth effectiveness tests were based upon 
tests conducted by the agency on existing produc- 
tion vehicles and upon confidential brake develop- 
ment test data submitted by General Motors, Ford 
and Chrysler. Based upon its analysis of these data, 
the agency concluded that the proposed stopping 
distances for both the third and fourth effec- 
tiveness tests for vehicles with a G VWR of 8,000 to 
10,000 lbs., including vehicles with unusually high 
centers of gravity and with both short and long 
wheelbases (which typically are more difficult to 
design brakes for than other vehicles), could be 
met without anti-lock or similar devices. Instead, 
the requirements could be met by modifications to 
such vehicle components as brake linings, wheel 
cylinders, master cylinders, and combination 
valves. 

This conclusion does not, however, fully resolve 
the concerns raised about the requirements as 
they relate to final stage manufacturers. As noted 
above, final stage manufacturers, typically pur- 
chase incomplete vehicles from large manufac- 
turers and complete the vehicles, often for 
specialized needs. Since only a limited number of 
incomplete vehicle designs are available for pur- 
chase, a final stage manufacturer must use the 
same incomplete vehicle design for widely varying 
applications. A given incomplete vehicle design 
may be completed as a pickup, a recreational vehi- 
cle, or a high cube van. Diverse equipment may be 
added such as service cranes, lift gates, ladders, 
aerial devices, and snow plows. Assuming that a 
final stage manufacturer does not redesign the 
braking system for each different use, the braking 
system sold with the incomplete vehicle by its 
manufacturer must serve applications with widely 
varying centers of gravity (i.e., varying both ver- 
tically and horizontally). 

The agency estimates that a 10 percent rise in 
center of gravity location will lengthen the stop- 
ping distance of a typical vehicle by three percent 
if it is operating at the limit of tire traction for its 
rear wheels. Changes in horizontal center of grav- 
ity will also lengthen stopping distances in some in- 
stances. It follows that a vehicle which would 
barely meet the requirements of the proposed 
standard at the specific center of gravity for which 
it is designed, which would be the case for some 
vehicles with a GVWR of 8,000 to 10,000 lbs., would 
not be able to meet the requirements at centers 



of gravity widely varying from the design one. 

The agency agrees, after analysis of the com- 
ments received from final stage manufacturers, 
their trade associations, and incomplete vehicle 
manufacturers, that the increased center of gravi- 
ty limitations which might be established for some 
vehicles of 8,000 to 10,000 lbs. GVWR if the pro- 
posal were adopted would pose significant dif- 
ficulties for final stage manufacturers. (Some 
limitations are currently established by in- 
complete vehicle manufacturers in connection with 
their certification of Standards 212, 219, and 301.) 
In some instances, a final stage manufacturer 
would be unable to simply complete vehicles on the 
same incomplete vehicle that it is accustomed to 
using, as the center of gravity of the completed 
vehicles would not be within the center of gravity 
envelope specified by the incomplete vehicle 
manufacturer. 

The final stage manufacturer would be faced 
with buying the same incomplete vehicles as 
before and recertifying them and possibly rede- 
signing their braking systems. Since the sales of in- 
complete vehicles to final stage manufacturers are 
a very small percentage of the light truck sales of 
the incomplete vehicle manufacturers, the in- 
complete vehicle manufacturers are not likely to 
be willing to accommodate the final stage manufac- 
turers by making major modifications to the line of 
incomplete vehicles they offer for sale, such as pro- 
viding incomplete vehicles which are designed for 
a broader range of centers of gravity. The in- 
complete vehicle manufacturers have themselves 
indicated this reluctance in a number of rulemak- 
ings. 

The agency has dealt with the certification prob- 
lems of final stage manufacturers during other 
rulemaking proceedings. Since final stage manu- 
facturers are often very small companies, which 
produce limited numbers of speciality vehicles, 
they often have limited resources for redesign- 
ing their vehicles, testing their vehicles for compli- 
ance with applicable safety standards, or making 
engineering judgments about the effect changes in 
a vehicle's center of gravity will have on the vehi- 
cle's performance. Therefore, the agency has 
sought to limit, consistent with the needs of safety, 
the compliance burdens on final stage manufac- 
turers. 

For example, the agency established special pro- 
visions affording relief to final stage manufac- 



PART 571; S 105-83-PRE 56 



turers in Standards 212, Windshield Mounting, 
and 219, Windshield Zone Intrusion. See notice of 
Final Rule, published in the Federal Register (45 
FR 22044) on April 3, 1980. One of the final stage 
manufacturer problems that was addressed in 
that rulemaking proceeding was center of gravity 
limitations established by incomplete vehicle 
manufacturers. The agency added the special pro- 
visions to Standards 212 and 219 for the purpose 
of inducing the reduction of center of gravity 
restrictions placed on final stage manufacturers 
by incomplete vehicle manufacturers. 

In order to ease the certification problems of 
final stage manufacturers that are related to 
Standard 105, while providing the maximum 
safety benefits that are consistent with that ob- 
jective, the agency determined that third effec- 
tiveness requirements should not apply to 
vehicles, other than school buses, with a GVWR 
of 8,000 to 10,000 lbs. The problem of center of 
gravity limitations as it relates to the proposed 
test requirements is primarily limited to the third 
effectiveness (lightly loaded) test. Since the test 
is conducted while the vehicle is in an unloaded 
condition, the manufacturer is constrained to test 
at the vehicle's center of gravity of the vehicle as 
configured. Center of gravity is not a serious 
problem for the other effectiveness tests, which 
are conducted at GVWR. For those tests, the 
manufacturer may load the vehicle in a way so as 
to lower the center of gravity and make com- 
pliance easier. 

In order to provide manufacturers with some 
additional leeway in balancing the performance of 
their braking systems for both fully loaded and 
lightly loaded conditions, the agency also decided 
that the fourth effectiveness (fully loaded) stop- 
ping distances should be extended by approx- 
imately 10 percent for the 8,000 to 10.000 lb. 
GVWR vehicles. As noted above, if fourth effec- 
tiveness requirements are too stringent, vehicles 
would need overly powerful rear brakes that are 
prone to lock-up in the lightly loaded condition. 
The agency recognizes that it is more difficult to 
meet the proposed fourth effectiveness require- 
ments for this class of vehicles without producing 
vehicles that are prone to lock-up, though, as 
indicated above, test data indicate that it can 
be accomplished. The relaxation of the fourth 
effectiveness requirements will assure that the 
manufacturers can use braking systems that 



perform well in the lightly loaded condition. 

In making these modifications to the proposed 
requirements for vehicles with a GVWR of 8,000 
to 10,000 lbs., the agency decided that school 
buses within that weight class should be treated 
separately. School buses are already required to 
meet Standard 105's requirements, though the 
October 1979 notice proposed making the re- 
quirements more stringent. As will be explained 
below, the agency decided that the proposal's 
fourth effectiveness requirements for school 
buses with a GVWR of 8,000 to 10,000 lbs. should 
be extended by 10 percent (the same as other 
vehicles within that weight class), with the excep- 
tion of the 30 mph test. The agency also decided 
that third effectiveness stopping distance re- 
quirements, at the longest distances proposed, 
should be applicable to school buses. 

Since school buses are already covered by 
Standard 105, the agency has a great deal of test 
data indicating their braking capability. Because 
school buses with a GVWR of 8,000 to 10,000 lbs. 
share most of the same characteristics as other 
vehicles with the same weight, the agency de- 
cided that fully loaded effectiveness require- 
ments should be the same for school buses as for 
other vehicles, with the one exception referred to 
above. School buses are already required to meet 
slightly more stringent requirements for fully 
loaded tests at 30 mph. Therefore, the agency will 
not relax those requirements. For fully loaded 
tests at other speeds, the requirements are more 
stringent than those currently in effect. 

As noted above, both agency test data and 
several comments indicate that the proposed 
third effectiveness test requirements (at the 
longest stopping distances proposed) can be met 
by vehicles with a GVWR of 8,000 to 10,000 lbs., 
particularly when the proposed fourth effec- 
tiveness stopping distances are slightly relaxed. 
The agency's decision that third effectiveness 
test requirements should not be applicable to 
vehicles with a GVWR of 8,000 to 10,000 lbs. 
resulted from possible center of gravity condi- 
tions that incomplete vehicle manufacturers 
might establish for the use of their vehicles. Since 
school buses do not have high centers of gravity 
or widely varying horizontal centers of gravity, 
they do not pose the same problems for final 
stage manufacturers as other vehicles. Moreover, 
since completing a vehicle as a school bus adds 



PART 571; S 105-83-PRE 57 



weight to the rear axle, the lightly loaded effec- 
tiveness test is more easily met by school buses 
than many other vehicles. The comments re- 
ceived that related to third effectiveness tests 
and final stage manufacturer difficulties did not 
identify the requirements for school buses as 
creating difficulties. Therefore, based upon a 
detailed analysis of test data, manufacturer- 
supplied information, and the comments, as well 
as on the safety need associated with school 
buses, the agency decided that third effec- 
tiveness test requirements should apply to school 
buses with a GVWR of 8,000 to 10,000 lbs. 

The agency believes that the modifications in 
the standard that were discussed above will 
eliminate any possibility that incomplete vehicle 
manufacturers will find it necessary either to 
establish more stringent center of gravity limita- 
tions on the use of their incomplete vehicles or to 
develop anti-lock or similar devices in order to be 
able to continue to produce incomplete vehicles 
that comply with the standard for the range of ap- 
plications needed by final stage manufacturers. 
Final stage manufacturers, therefore, will or- 
dinarily be able to rely on the incomplete vehicle 
manufacturer's certification of the braking 
system. 

In some rare cases, such as when a final stage 
manufacturer adds an axle or redesigns the brak- 
ing system of an incomplete vehicle, the final 
stage manufacturer will be required to recertify 
that the completed vehicle complies with the 
brake requirements. Depending upon the changes 
made, the final stage manufacturer may be able 
to certify based upon engineering judgments. If 
testing is required, the agency estimates that the 
costs of a full test sequence would be approx- 
imately $2,500, assuming that the manufacturer 
has no facilities, instrumentation or test person- 
nel of its own. Testing would not have to be con- 
ducted for each vehicle, but only for each vehicle 
type or, in some cases, the most problem prone 
configuration of several vehicle types. There are 
several test facilities and testing organizations 
distributed throughout the United States. 

Such major changes are rarely made by final 
stage manufacturers, and, if they are, they tend 
to be made by the larger of these manufacturers. 
When such changes are made, the agency 
believes it appropriate to require that the 
manufacturer making those changes ensure that 



the vehicle still complies with applicable Federal 
motor vehicle safety standards. 

In adopting these changes, the agency fol- 
lowed, in part, the suggestions of several of the 
commenters. The National Truck Equipment 
Association (NTEA), for example, suggested that 
if the agency extends the standard at this time, it 
should select 8,000 lbs. GVWR as the cutoff 
weight for Standard 105. That cutoff was said to 
address the brake proportioning difficulties in- 
herent in vehicles with a wide weight differential 
in their laden and unladen conditions. The agency 
declined to completely exempt vehicles of 8,000 
lbs. or greater GVWR from Standard 105's cover- 
age, since the standard offers many benefits in 
addition to those resulting from the requirements 
that would cause difficulties for final stage 
manufacturers. However, the agency did use 
8,000 lbs. GVWR as the cutoff weight for the 
standard's third effectiveness requirements, the 
requirements which most directly relate to the 
brake proportioning difficulties referred to by 
NTEA. 

The agency followed the suggestions of several 
incomplete vehicle manufacturers and other com- 
menters also in deciding to relax fourth effec- 
tiveness stopping distance requirements for 8,000 
to 10,000 lb. GVWR vehicles. Since the agency 
concluded that the requirements could be met as 
proposed without anti-lock or similar devices, 
albeit with some difficulty, the agency declined to 
adopt Chrysler's suggestion of a 16 percent ex- 
tension and instead chose the 10 percent exten- 
sion suggested by other comments. The agency 
decided, based on test data, that a 10 percent ex- 
tension would be sufficient to make it easier for 
manufacturers to assure that their vehicles' brak- 
ing systems perform well in both fully loaded and 
lightly loaded conditions. 

The agency considered and rejected the alter- 
native of adopting different test requirements for 
final stage manufacturers or providing final stage 
manufacturers with a longer period of leadtime 
than other manufacturers. Either approach would 
result in a safety standard that was applied on 
the basis of the particular manufacturer of a vehi- 
cle rather than the safety needs of a particular 
vehicle type. The National Traffic and Motor 
Vehicle Safety Act contemplates the application 
of standards based on vehicle type rather than by 
manufacturer. Further, the agency determined 



PART 571; S 105-83-PRE 58 



turers in Standards 212, Windshield Mounting, 
and 219, Windshield Zone Intrusion. See notice of 
Final Rule, published in the Federal Register (45 
FR 22044) on April 3, 1980. One of the final stage 
manufacturer problems that was addressed in 
that rulemaking proceeding was center of gravity 
limitations established by incomplete vehicle 
manufacturers. The agency added the special pro- 
visions to Standards 212 and 219 for the purpose 
of inducing the reduction of center of gravity 
restrictions placed on final stage manufacturers 
by incomplete vehicle manufacturers. 

In order to ease the certification problems of 
final stage manufacturers that are related to 
Standard 105, while providing the maximum 
safety benefits that are consistent with that ob- 
jective, the agency determined that third effec- 
tiveness requirements should not apply to 
vehicles, other than school buses, with a GVWR 
of 8,000 to 10,000 lbs. The problem of center of 
gravity limitations as it relates to the proposed 
test requirements is primarily limited to the third 
effectiveness (lightly loaded) test. Since the test 
is conducted while the vehicle is in an unloaded 
condition, the manufacturer is constrained to test 
at the vehicle's center of gravity of the vehicle as 
configured. Center of gravity is not a serious 
problem for the other effectiveness tests, which 
are conducted at GVWR. For those tests, the 
manufacturer may load the vehicle in a way so as 
to lower the center of gravity and make com- 
pliance easier. 

In order to provide manufacturers with some 
additional leeway in balancing the performance of 
their braking systems for both fully loaded and 
lightly loaded conditions, the agency also decided 
that the fourth effectiveness (fully loaded) stop- 
ping distances should be extended by approx- 
imately 10 percent for the 8,000 to 10,000 lb. 
GVWR vehicles. As noted above, if fourth effec- 
tiveness requirements are too stringent, vehicles 
would need overly powerful rear brakes that are 
prone to lock-up in the lightly loaded condition. 
The agency recognizes that it is more difficult to 
meet the proposed fourth effectiveness require- 
ments for this class of vehicles without producing 
vehicles that are prone to lock-up, though, as 
indicated above, test data indicate that it can 
be accomplished. The relaxation of the fourth 
effectiveness requirements will assure that the 
manufacturers can use braking systems that 



perform well in the lightly loaded condition. 

In making these modifications to the proposed 
requirements for vehicles with a GVWR of 8,000 
to 10,000 lbs., the agency decided that school 
buses within that weight class should be treated 
separately. School buses are already required to 
meet Standard 105's requirements, though the 
October 1979 notice proposed making the re- 
quirements more stringent. As will be explained 
below, the agency decided that the proposal's 
fourth effectiveness requirements for school 
buses with a GVWR of 8,000 to 10,000 lbs. should 
be extended by 10 percent (the same as other 
vehicles within that weight class), with the excep- 
tion of the 30 mph test. The agency also decided 
that third effectiveness stopping distance re- 
quirements, at the longest distances proposed, 
should be applicable to school buses. 

Since school buses are already covered by 
Standard 105, the agency has a great deal of test 
data indicating their braking capability. Because 
school buses with a GVWR of 8,000 to 10,000 lbs. 
share most of the same characteristics as other 
vehicles with the same weight, the agency de- 
cided that fully loaded effectiveness require- 
ments should be the same for school buses as for 
other vehicles, with the one exception referred to 
above. School buses are already required to meet 
slightly more stringent requirements for fully 
loaded tests at 30 mph. Therefore, the agency will 
not relax those requirements. For fully loaded 
tests at other speeds, the requirements are more 
stringent than those currently in effect. 

As noted above, both agency test data and 
several comments indicate that the proposed 
third effectiveness test requirements (at the 
longest stopping distances proposed) can be met 
by vehicles with a GVWR of 8,000 to 10,000 lbs., 
particularly when the proposed fourth effec- 
tiveness stopping distances are slightly relaxed. 
The agency's decision that third effectiveness 
test requirements should not be applicable to 
vehicles with a GVWR of 8,000 to 10,000 lbs. 
resulted from possible center of gravity condi- 
tions that incomplete vehicle manufacturers 
might establish for the use of their vehicles. Since 
school buses do not have high centers of gravity 
or widely varying horizontal centers of gravity, 
they do not pose the same problems for final 
stage manufacturers as other vehicles. Moreover, 
since completing a vehicle as a school bus adds 



PART 571; S 105-83-PRE 57 



weight to the rear axle, the lightly loaded effec- 
tiveness test is more easily met by school buses 
than many other vehicles. The comments re- 
ceived that related to third effectiveness tests 
and final stage manufacturer difficulties did not 
identify the requirements for school buses as 
creating difficulties. Therefore, based upon a 
detailed analysis of test data, manufacturer- 
supplied information, and the comments, as well 
as on the safety need associated with school 
buses, the agency decided that third effec- 
tiveness test requirements should apply to school 
buses with a GVWR of 8,000 to 10,000 lbs. 

The agency believes that the modifications in 
the standard that were discussed above will 
eliminate any possibility that incomplete vehicle 
manufacturers will find it necessary either to 
establish more stringent center of gravity limita- 
tions on the use of their incomplete vehicles or to 
develop anti-lock or similar devices in order to be 
able to continue to produce incomplete vehicles 
that comply with the standard for the range of ap- 
plications needed by final stage manufacturers. 
Final stage manufacturers, therefore, will or- 
dinarily be able to rely on the incomplete vehicle 
manufacturer's certification of the braking 
system. 

In some rare cases, such as when a final stage 
manufacturer adds an axle or redesigns the brak- 
ing system of an incomplete vehicle, the final 
stage manufacturer will be required to recertify 
that the completed vehicle complies with the 
brake requirements. Depending upon the changes 
made, the final stage manufacturer may be able 
to certify based upon engineering judgments. If 
testing is required, the agency estimates that the 
costs of a full test sequence would be approx- 
imately $2,500, assuming that the manufacturer 
has no facilities, instrumentation or test person- 
nel of its own. Testing would not have to be con- 
ducted for each vehicle, but only for each vehicle 
type or, in some cases, the most problem prone 
configuration of several vehicle types. There are 
several test facilities and testing organizations 
distributed throughout the United States. 

Such major changes are rarely made by final 
stage manufacturers, and, if they are, they tend 
to be made by the larger of these manufacturers. 
When such changes are made, the agency 
believes it appropriate to require that the 
manufacturer making those changes ensure that 



the vehicle still complies with applicable Federal 
motor vehicle safety standards. 

In adopting these changes, the agency fol- 
lowed, in part, the suggestions of several of the 
commenters. The National Truck Equipment 
Association (NTEA), for example, suggested that 
if the agency extends the standard at this time, it 
should select 8,000 lbs. GVWR as the cutoff 
weight for Standard 105. That cutoff was said to 
address the brake proportioning difficulties in- 
herent in vehicles with a wide weight differential 
in their laden and unladen conditions. The agency 
declined to completely exempt vehicles of 8,000 
lbs. or greater GVWR from Standard 105's cover- 
age, since the standard offers many benefits in 
addition to those resulting from the requirements 
that would cause difficulties for final stage 
manufacturers. However, the agency did use 
8,000 lbs. GVWR as the cutoff weight for the 
standard's third effectiveness requirements, the 
requirements which most directly relate to the 
brake proportioning difficulties referred to by 
NTEA. 

The agency followed the suggestions of several 
incomplete vehicle manufacturers and other com- 
menters also in deciding to relax fourth effec- 
tiveness stopping distance requirements for 8,000 
to 10,000 lb. GVWR vehicles. Since the agency 
concluded that the requirements could be met as 
proposed without anti-lock or similar devices, 
albeit with some difficulty, the agency declined to 
adopt Chrysler's suggestion of a 16 percent ex- 
tension and instead chose the 10 percent exten- 
sion suggested by other comments. The agency 
decided, based on test data, that a 10 percent ex- 
tension would be sufficient to make it easier for 
manufacturers to assure that their vehicles' brak- 
ing systems perform well in both fully loaded and 
lightly loaded conditions. 

The agency considered and rejected the alter- 
native of adopting different test requirements for 
final stage manufacturers or providing final stage 
manufacturers with a longer period of leadtime 
than other manufacturers. Either approach would 
result in a safety standard that was applied on 
the basis of the particular manufacturer of a vehi- 
cle rather than the safety needs of a particular 
vehicle type. The National Traffic and Motor 
Vehicle Safety Act contemplates the application 
of standards based on vehicle type rather than by 
manufacturer. Further, the agency determined 



PART 571; S 105-83-PRE 58 



that the requirements as adopted, including lead- 
time, are appropriate for all manufacturers. Since 
incomplete vehicle manufacturers should not find 
it necessary to place significant new restrictions 
on the use of their chassis as a result of Standard 
105, final stage manufacturers should not require 
any redesign of their vehicles. 

While the standard's requirements have been 
relaxed to reduce certification burdens on final 
stage manufacturers and to make it easier for 
manufacturers to assure that their vehicles' brak- 
ing systems are balanced for both lightly loaded 
and fully loaded conditions, the agency encour- 
ages manufacturers to recognize the safety ad- 
vantages offered by better braking systems and, 
where possible, to produce vehicles which meet 
or exceed the more stringent requirements that 
were proposed. 

A number of more general comments were 
received on the appropriateness of the 8,000 lb. 
GVWR boundary. American Motors/Jeep stated 
that it supported adoption of the 8,000 lb. GVWR 
cutoff as a reasonable first step in addressing the 
brake proportioning difficulties inherent in 
vehicles with a wide weight differential between 
their loaded and unloaded conditions. However, 
hi the commenter suggested that the agency in- 
vestigate the feasibility of developing new 
criteria that respond directly to the laden to 
unladen ratio regardless of the vehicle's GVWR. 
Other comments, including those of General 
Motors, the Motor Vehicle Manufacturer's 
Association, Wagner Electric and NTEA also sug- 
gested that the agency consider an approach us- 
ing a laden/unladen weight distribution ratio 
criterion. Several of those commenters empha- 
sized that as vehicle downsizing continues, 
vehicles with a GVWR of under 8,000 lbs. will 
have the same balance problems as vehicles of 
8,000 to 10,000 lbs. GVWR. 

The agency recognizes that this may become a 
problem in the future, but only if manufacturers 
seek to hold GVWR constant as they downsize 
their fleets rather than keeping payload constant. 
Since the agency believes payload to be a better 
measure of a vehicle's utility than GVWR, the 
agency encourages manufacturers to keep a con- 
stant payload instead of a constant GVWR as 
they downsize their vehicles. The agency will 
monitor developments in this area. 

A comment submitted by Daimler-Benz stated 



that it saw no justification for an additional 
weight class of 8,000 to 10,000 lbs. GVWR and 
suggested that those vehicles be included with 
vehicles over 10,000 lbs. GVWR. According to 
that commenter, the brake regulations of some 
countries have a 3,500 kilogram (7716 lb.) weight 
limit, and some design characteristics of vehicles 
over 10,000 lbs. GVWR can also be found on 
vehicles with a GVWR of 8,000 lbs. As noted in 
the October 1979 notice, the agency is considering 
establishing more complete brake requirements 
for vehicles with a GVWR of over 10,000 lbs. but 
has not yet done so. This final rule brings the 
more complete requirements of Standard 105 to 
vehicles with a GVWR of 8,000 to 10,000 lbs. and 
includes requirements that are appropriate for all 
vehicles in that class, whatever their design 
characteristics. 

As noted above, the comments concerning ef- 
fectiveness requirements were largely directed 
at the requirements for vehicles with a GVWR of 
8,000 to 10,000 lbs. However, some of the com- 
ments, including those of Chrysler and Wagner 
Electric, were also directed toward the fourth ef- 
fectiveness requirements in general. Both the 
agency's own tests and confidential data submit- 
ted by the manufacturers indicate that recent 
models of almost all vehicles under 8,000 lbs. 
GVWR pass the effectiveness requirements. For 
any vehicles that do not, only minor changes 
would be required. As discussed above, it is 
easier to design braking systems for these 
vehicles than larger vehicles since they do not 
have as wide a weight differential between their 
loaded and unloaded conditions. Moreover, the 
type of work-performing equipment that can 
create center of gravity problems for final stage 
manufacturers is generally installed on vehicles 
with a GVWR of 8,000 lbs. or more. Therefore, no 
changes were made in the requirements as pro- 
posed for vehicles with a GVWR of under 8,000 
lbs. 

Comments submitted by Ford and Chrysler re- 
quested that both second and fourth effectiveness 
tests at 80 mph be eliminated in light of the 55 
mph national speed limit. Ford also noted that ac- 
tions required for fuel economy decrease the max- 
imum speed capability of vehicles. The standard 
is written to require that the 80 mph test be met 
only if vehicles are capable of attaining a speed of 
84 mph. Therefore, vehicles which cannot attain 



Wi 



PART 571; S 105-83-PRE 59 



that speed need not comply with the 80 mph re- 
quirements. Since many vehicles can attain 
speeds well in excess of 80 mph and some vehicles 
are at times driven at those high speeds, despite 
the 55 mph national speed limit, the agency 
believes that 80 mph requirements are appro- 
priate and in the interest of safety. 

Fade Recovery; Water Recovery 

The October 1979 notice explained that the 
fade and recovery requirements were included to 
assure that a vehicle's braking performance is 
satisfactory when exposed to the high brake 
temperatures caused by prolonged or severe use, 
such as is found in long, downhill driving. The pro- 
posal requires that vehicles be capable of passing 
two successive fade and recovery tests. The 
water recovery requirements assure that a vehi- 
cle's braking system performs adequately after 
immersion in water. 

The comments on these tests were limited to 
the fade and recovery requirements. Chrysler 
stated that the fade tests simulate abuse that is 
rarely, if ever, encountered in actual customer 
service. That commenter stated that the fade 
tests, coupled with the fourth effectiveness re- 
quirements which follow the fade tests, would 
result in braking systems that are biased toward 
the rear brakes. According to Chrysler, rear 
biased brakes would be prone to lock-up in the 
lightly loaded condition. Wagner Electric submit- 
ted a similar comment and suggested that the sec- 
ond fade and recovery test and the fourth effec- 
tiveness test were redundant. That commenter 
suggested that those two tests be eliminated to 
simplify the test procedures of Standard 105. 

The concern that the test requirements would 
result in braking systems biased toward the rear 
brakes was largely discussed in the preceding 
section of this notice. The proposed requirements 
of Standard 105 included both fully loaded and 
lightly loaded tests. The agency concluded, based 
upon its own vehicle tests and on information sub- 
mitted by manufacturers, that the proposed test 
requirements could be met by changes in various 
braking system components. So long as both fully 
loaded and lightly loaded requirements were met, 
the braking system would be properly balanced 
for both fully loaded and lightly loaded condi- 
tions. By extending the fourth effectiveness re- 
quirements by 10 percent for vehicles with a 



GVWR of 8,000 to 10,000 lbs., additional leeway 
was provided to manufacturers in designing their 
braking systems to be properly balanced. As 
noted above, no changes were made in the re- 
quirements applicable to vehicles with a GVWR 
of under 8,000 lbs., since recent models of most of 
those vehicles already pass the effectiveness re- 
quirements. Only minor changes are required for 
those vehicles that do not. 

The two fade tests were designed to produce 
first a mild to moderate fade condition and then a 
more severe fade condition. Light fade occurs in 
vehicles even in low speed applications such as in 
heavy traffic. Moderate to severe fade is a condi- 
tion that may occur when vehicles are used on 
hilly or mountainous roads, especially when 
heavy loads are carried. Far from being redun- 
dant, the second fade test simulates the type of 
fade experienced during long mountain descents. 
The agency has verified that the temperatures 
produced by the test sequence are the same 
temperatures as sometimes experienced during 
long mountain descents. The fade and recovery 
test requirements assure that brakes do not per- 
form abnormally while subject to the heat caused 
by severe use or during the time that the brakes 
are cooling off after severe use. 

The fourth effectiveness test is a complete ef- 
fectiveness test that is conducted after most of 
the other tests, including the fade tests, have 
been completed. This test is included to give an 
overall system evaluation to assure that a brak- 
ing system retains satisfactory characteristics 
related to effectiveness, pedal force, and sen- 
sitivity after exposure to the types of conditions 
simulated during the test sequence. 

A comment submitted by the American Truck- 
ing Associations (ATA) suggested that the pro- 
posed fade requirements are severe enough to 
adversely affect user acceptance in normal serv- 
ice. According to ATA, compromises in such 
things as loss of feel and hard pedal in order to 
achieve greater fade resistance may be neces- 
sary. The comment also suggested that fade 
resistance tests developed in the past may be out- 
dated as vehicles are becoming less powerful. 

The agency tested a number of production 
vehicles before proposing the fade requirements 
and found that almost all of them met the re- 
quirements. The only vehicles tested by the agen- 
cy which appeared to present problems were 



PART 571; S 105-83-PRE 60 



i 



that the requirements as adopted, including lead- 
time, are appropriate for all manufacturers. Since 
incomplete vehicle manufacturers should not find 
it necessary to place significant new restrictions 
on the use of their chassis as a result of Standard 
105, final stage manufacturers should not require 
any redesign of their vehicles. 

While the standard's requirements have been 
relaxed to reduce certification burdens on final 
stage manufacturers and to make it easier for 
manufacturers to assure that their vehicles' brak- 
ing systems are balanced for both lightly loaded 
and fully loaded conditions, the agency encour- 
ages manufacturers to recognize the safety ad- 
vantages offered by better braking systems and, 
where possible, to produce vehicles which meet 
or exceed the more stringent requirements that 
were proposed. 

A number of more general comments were 
received on the appropriateness of the 8,000 lb. 
GVWR boundary. American Motors/Jeep stated 
that it supported adoption of the 8,000 lb. GVWR 
cutoff as a reasonable first step in addressing the 
brake proportioning difficulties inherent in 
vehicles with a wide weight differential between 
their loaded and unloaded conditions. However, 
the commenter suggested that the agency in- 
vestigate the feasibility of developing new 
criteria that respond directly to the laden to 
unladen ratio regardless of the vehicle's GVWR. 
Other comments, including those of General 
Motors, the Motor Vehicle Manufacturer's 
Association, Wagner Electric and NTEA also sug- 
gested that the agency consider an approach us- 
ing a laden/unladen weight distribution ratio 
criterion. Several of those commenters empha- 
sized that as vehicle downsizing continues, 
vehicles with a GVWR of under 8,000 lbs. will 
have the same balance problems as vehicles of 
8,000 to 10,000 lbs. GVWR. 

The agency recognizes that this may become a 
problem in the future, but only if manufacturers 
seek to hold GVWR constant as they downsize 
their fleets rather than keeping payload constant. 
Since the agency believes payload to be a better 
measure of a vehicle's utility than GVWR, the 
agency encourages manufacturers to keep a con- 
stant payload instead of a constant GVWR as 
they downsize their vehicles. The agency will 
monitor developments in this area. 

A comment submitted by Daimler-Benz stated 



that it saw no justification for an additional 
weight class of 8,000 to 10,000 lbs. GVWR and 
suggested that those vehicles be included with 
vehicles over 10,000 lbs. GVWR. According to 
that commenter, the brake regulations of some 
countries have a 3,500 kilogram (7716 lb.) weight 
limit, and some design characteristics of vehicles 
over 10,000 lbs. GVWR can also be found on 
vehicles with a GVWR of 8,000 lbs. As noted in 
the October 1979 notice, the agency is considering 
establishing more complete brake requirements 
for vehicles with a GVWR of over 10,000 lbs. but 
has not yet done so. This final rule brings the 
more complete requirements of Standard 105 to 
vehicles with a GVWR of 8,000 to 10,000 lbs. and 
includes requirements that are appropriate for all 
vehicles in that class, whatever their design 
characteristics. 

As noted above, the comments concerning ef- 
fectiveness requirements were largely directed 
at the requirements for vehicles with a GVWR of 
8,000 to 10,000 lbs. However, some of the com- 
ments, including those of Chrysler and Wagner 
Electric, were also directed toward the fourth ef- 
fectiveness requirements in general. Both the 
agency's own tests and confidential data submit- 
ted by the manufacturers indicate that recent 
models of almost all vehicles under 8,000 lbs. 
GVWR pass the effectiveness requirements. For 
any vehicles that do not, only minor changes 
would be required. As discussed above, it is 
easier to design braking systems for these 
vehicles than larger vehicles since they do not 
have as wide a weight differential between their 
loaded and unloaded conditions. Moreover, the 
type of work-performing equipment that can 
create center of gravity problems for final stage 
manufacturers is generally installed on vehicles 
with a GVWR of 8,000 lbs. or more. Therefore, no 
changes were made in the requirements as pro- 
posed for vehicles with a GVWR of under 8,000 
lbs. 

Comments submitted by Ford and Chrysler re- 
quested that both second and fourth effectiveness 
tests at 80 mph be eliminated in light of the 55 
mph national speed limit. Ford also noted that ac- 
tions required for fuel economy decrease the max- 
imum speed capability of vehicles. The standard 
is written to require that the 80 mph test be met 
only if vehicles are capable of attaining a speed of 
84 mph. Therefore, vehicles which cannot attain 



PART 571; S 105-83-PRE 59 



that speed need not comply with the 80 mph re- 
quirements. Since many vehicles can attain 
speeds well in excess of 80 mph and some vehicles 
are at times driven at those high speeds, despite 
the 55 mph national speed limit, the agency 
believes that 80 mph requirements are appro- 
priate and in the interest of safety. 

Fade Recovery; Water Recovery 

The October 1979 notice explained that the 
fade and recovery requirements were included to 
assure that a vehicle's braking performance is 
satisfactory when exposed to the high brake 
temperatures caused by prolonged or severe use, 
such as is found in long, downhill driving. The pro- 
posal requires that vehicles be capable of passing 
two successive fade and recovery tests. The 
water recovery requirements assure that a vehi- 
cle's braking system performs adequately after 
immersion in water. 

The comments on these tests were limited to 
the fade and recovery requirements. Chrysler 
stated that the fade tests simulate abuse that is 
rarely, if ever, encountered in actual customer 
service. That commenter stated that the fade 
tests, coupled with the fourth effectiveness re- 
quirements which follow the fade tests, would 
result in braking systems that are biased toward 
the rear brakes. According to Chrysler, rear 
biased brakes would be prone to lock-up in the 
lightly loaded condition. Wagner Electric submit- 
ted a similar comment and suggested that the sec- 
ond fade and recovery test and the fourth effec- 
tiveness test were redundant. That commenter 
suggested that those two tests be eliminated to 
simplify the test procedures of Standard 105. 

The concern that the test requirements would 
result in braking systems biased toward the rear 
brakes was largely discussed in the preceding 
section of this notice. The proposed requirements 
of Standard 105 included both fully loaded and 
lightly loaded tests. The agency concluded, based 
upon its own vehicle tests and on information sub- 
mitted by manufacturers, that the proposed test 
requirements could be met by changes in various 
braking system components. So long as both fully 
loaded and lightly loaded requirements were met, 
the braking system would be properly balanced 
for both fully loaded and lightly loaded condi- 
tions. By extending the fourth effectiveness re- 
quirements by 10 percent for vehicles with a 



GVWR of 8,000 to 10,000 lbs., additional leeway 
was provided to manufacturers in designing their 4 
braking systems to be properly balanced. As ' 
noted above, no changes were made in the re- 
quirements applicable to vehicles with a GVWR 
of under 8,000 lbs., since recent models of most of 
those vehicles already pass the effectiveness re- 
quirements. Only minor changes are required for 
those vehicles that do not. 

The two fade tests were designed to produce 
first a mild to moderate fade condition and then a 
more severe fade condition. Light fade occurs in 
vehicles even in low speed applications such as in 
heavy traffic. Moderate to severe fade is a condi- 
tion that may occur when vehicles are used on 
hilly or mountainous roads, especially when 
heavy loads are carried. Far from being redun- 
dant, the second fade test simulates the type of 
fade experienced during long mountain descents. 
The agency has verified that the temperatures 
produced by the test sequence are the same 
temperatures as sometimes experienced during 
long mountain descents. The fade and recovery 
test requirements assure that brakes do not per- 
form abnormally while subject to the heat caused 
by severe use or during the time that the brakes 
are cooling off after severe use. . 

The fourth effectiveness test is a complete ef- m 
fectiveness test that is conducted after most of ^ 
the other tests, including the fade tests, have 
been completed. This test is included to give an 
overall system evaluation to assure that a brak- 
ing system retains satisfactory characteristics 
related to effectiveness, pedal force, and sen- 
sitivity after exposure to the types of conditions 
simulated during the test sequence. 

A comment submitted by the American Truck- 
ing Associations (ATA) suggested that the pro- 
posed fade requirements are severe enough to 
adversely affect user acceptance in normal serv- 
ice. According to ATA, compromises in such 
things as loss of feel and hard pedal in order to 
achieve greater fade resistance may be neces- 
sary. The comment also suggested that fade 
resistance tests developed in the past may be out- 
dated as vehicles are becoming less powerful. 

The agency tested a number of production 
vehicles before proposing the fade requirements 
and found that almost all of them met the re- 
quirements. The only vehicles tested by the agen- 
cy which appeared to present problems were 



PART 571; S 105-83-PRE 60 



some small imported pickup trucks. Since many 
other vehicles passed the requirements, without 
having problems such as loss of feel or hard 
pedal, it is clear that braking systems can be 
designed to meet the fade requirements without 
having the problems suggested by ATA. Since 
fade tests primarily apply to a vehicle's downhill 
performance, the requirements are appropriate 
for vehicles even if they are less powerful than in 
the past. 

Partial System Failure; Failed 
Power-Assist/Power Units 

Partial system failure requirements were in- 
cluded to ensure that a vehicle's brakes are 
capable of bringing the vehicle to a controlled 
stop in a reasonable distance if a part of the serv- 
ice brake system should fail. Stopping distance 
requirements were also proposed for vehicles 
with failed power-assist or brake power units. 

The October 1979 notice explained that many 
manufacturers currently provide what are called 
split brake systems to provide braking capacity 
in the event of a partial failure. The split system 
consists of two or more brake subsystems, each 
of which is not affected by leakage or failure in 
the other subsystem. Split systems are typically 
used on passenger cars, school buses, light trucks 
and vans. Under the proposed requirements, all 
hydraulic braked vehicles are required to utilize 
a split or redundant brake system. 

Several commenters stated that the stopping 
distances for partial failure and for inoperative 
brake power and power assist units for vehicles 
with a GVWR over 10,000 lbs. are too stringent. 
Daimler-Benz stated that the requirements could 
only be met if the operative braking system has 
an increased capacity. 

In a late submission to the docket, Wagner 
Electric asserted that agency tests substan- 
tiating the capability to meet the partial system 
requirements for vehicles over 10,000 lbs. were 
based on the two most effective of the possible 
partial systems. The commenter stated that no 
data was provided on vertical split systems and 
suggested that the requirements as proposed 
would encourage forms of split systems, such as 
vertical split systems, that would inordinately in- 
crease the level of front brake torque (i.e., make 
the front brakes overly powerful) and contribute 
toward lock-up on icy or wet roads. (A vertical 



split system essentially consists of one sub- 
system that supplies braking power to the front 
brakes and another subsystem that provides 
power to the back brakes. This contrasts with a 
variety of other types of split systems. Some 
horizontal split systems, for example, consist of 
two subsystems that each provide some braking 
power to each wheel. The two types of split 
systems which Wagner Electric's comment sug- 
gested are the most effective are a horizontal 
split and a 1- V2 x V2 split, a system with some of 
the attributes of a horizontal split system.) A 
comment submitted by ATA also suggested that 
the requirements would mandate overly power- 
ful, aggressive front brakes. 

Several commenters suggested that the stop- 
ping distance requirements for vehicles over 
10,000 lbs. GVWR be relaxed. Wagner Electric 
suggested that the requirements currently in ef- 
fect for school buses be adopted. 

The partial system failure and failed power 
assist or brake power unit requirements were 
proposed by the agency after careful analysis of 
its own vehicle test results and of confidential 
data submitted by manufacturers. These data in- 
dicate that many production vehicles already 
meet the proposed requirements. The current 
school bus requirements were issued in 1975 
under a short-term statutory deadline. Analysis 
of current school bus data indicates that many 
school buses already meet the more stringent re- 
quirements proposed by the October 1979 notice. 
As with other stopping distance requirements, 
there is some increment of safety benefit for 
each reduction of stopping distance. When par- 
tial failure of the service brake system occurs or 
brake power or power assist units become in- 
operative, it is important that a vehicle be able to 
stop in a reasonable distance, especially when 
that vehicle has the aggressivity associated with 
a GVWR of over 10.000 lbs. 

In regard to Wagner Electric's comment con- 
cerning vertical split systems, it is true that if 
the subsystem providing power to the rear 
brakes in a vertical split system fails, the sub- 
system providing power to the front brakes 
would be required to meet the stopping distance 
requirements under the standard. Therefore, in 
order to meet this requirement with a vertical 
split system, a vehicle would need relatively 
powerful front brakes. Similar requirements 



PART 571; S 105-83-PRE 61 



have been in effect for vehicles with air brakes 
under Standard 121, and European regulations 
necessitate even more powerful front axle brakes 
without safety problems. 

Moreover, in keeping with the National Traffic 
and Motor Vehicle Safety Act, the requirements 
are written as performance requirements and not 
design requirements. Manufacturers may meet 
the requirements in many different ways and are 
not required to use vertical split systems. Indeed, 
the selection of a means of compliance that poses 
significant safety risks could raise a safety defect 
issue. If Wagner Electric is concerned that ver- 
tical split systems may contribute to lock-up 
when used on some vehicle configurations, the 
manufacturer has the option to use other types of 
split systems, such as horizontal splits, or a 
redundant split system. When one of the subsys- 
tems of a horizontal split system fails, some brak- 
ing power is still provided to each wheel by the 
operative subsystem, so the stopping distances 
do not have to be met solely by the power pro- 
vided to the front wheels. Therefore, the braking 
system does not have to have relatively powerful 
front brakes in order to meet the requirements. 
This would also be true for some other types of 
split systems and for redundant systems. 

Wagner Electric also stated that the 150 lb. 
maximum pedal force specified for the re- 
quirements is too low and might result in overly 
sensitive brakes. That company suggested that a 
200 lb. pedal force be adopted. 

An analysis of the data referred to above in- 
dicates that many vehicles on the road already 
meet this requirement, without experiencing 
problems of oversensitivity. While Wagner Elec- 
tric suggests in its comment that even a small 
person can reach a 200 lb. pedal effort, the agency 
has found that small females have difficulty even 
applying forces of less than 150 lbs. 

Moreover, when a driver is used to applying 
very little force to bring a vehicle to a stop, the 
driver is likely to believe that the braking system 
has failed entirely, rather than only partially, 
if the driver applies maximum force and cannot 
feel the vehicle braking. Reports of "no brakes" 
are sometimes given in accident reports where 
only a partial failure has occurred. Therefore, 
it is important that a vehicle's braking sys- 
tem respond noticeably when a driver is apply- 
ing significant force in a partial failure or 



failed power assist or brake power unit situation. 

A comment submitted by the Metropolitan 
Transit Agency of Dade County, Florida, called 
for lower pedal force requirements. That com- 
menter cited the difficulty smaller drivers have 
in bringing a large bus to a stop after loss of 
vacuum. In establishing the 150 lb. pedal force, 
the agency took account of both the need to 
establish a level of pedal force appropriate for 
smaller drivers and to keep it high enough that 
brakes will not be oversensitive in ordinary use. 
That commenter also suggested that the agency 
establish requirements for vacuum reserve. The 
agency included optional procedures in Standard 
105 that encourage manufacturers to include 
vacuum reserves by permitting slightly longer 
stopping distances in the no power tests if the 
vehicle has the capability of making several stops 
in consecutive order with gradually decreasing 
capabilities. The agency recognizes the safety ad- 
vantages offered by vacuum reserves, but has 
not, as of yet, proposed that they be required. 

A comment submitted by the Recreation Vehi- 
cle Industry Association (RVIA) requested that 
the test procedures for vehicles with a GVWR of 
over 10,000 lbs. be changed to require less stops 
and snubs to condition the brakes. The agency 
declines to make this change since a significant 
number of stops and snubs is required in order 
that a braking system's capability be tested in a 
"worn-in" condition. 

Equipment Integrity 

Comments on the requirements concerning 
equipment integrity were primarily limited to the 
spile stop requirements. RVIA suggested that 
the spike stop test requirements are inappro- 
priate for motor homes. According to RVIA, it is 
unaware of a single case where a weakness that 
the spike stop test would uncover has ever been 
found in a motor home. 

The spike stop test requirements were devel- 
oped to determine the structural integrity of a 
vehicle's braking system. Vehicles must be 
capable of making several very sudden stops 
without loss of brake system structural integrity. 
Virtually all types of vehicles, including motor 
homes, are at times subjected to the abuse caused 
by very sudden stops. If the vehicle's braking 
system loses its structural integrity during such 
stops, serious accidents could result. 



PART 571; S 105-83-PRE 62 



some small imported pickup trucks. Since many 
other vehicles passed the requirements, without 
having problems such as loss of feel or hard 
pedal, it is clear that braking systems can be 
designed to meet the fade requirements without 
having the problems suggested by ATA. Since 
fade tests primarily apply to a vehicle's downhill 
performance, the requirements are appropriate 
for vehicles even if they are less powerful than in 
the past. 

Partial System Failure; Failed 
Power-Assist/Power Units 

Partial system failure requirements were in- 
cluded to ensure that a vehicle's brakes are 
capable of bringing the vehicle to a controlled 
stop in a reasonable distance if a part of the serv- 
ice brake system should fail. Stopping distance 
requirements were also proposed for vehicles 
with failed power-assist or brake power units. 

The October 1979 notice explained that many 
manufacturers currently provide what are called 
split brake systems to provide braking capacity 
in the event of a partial failure. The split system 
consists of two or more brake subsystems, each 
of which is not affected by leakage or failure in 
the other subsystem. Split systems are typically 
used on passenger cars, school buses, light trucks 
and vans. Under the proposed requirements, all 
hydraulic braked vehicles are required to utilize 
a split or redundant brake system. 

Several commenters stated that the stopping 
distances for partial failure and for inoperative 
brake power and power assist units for vehicles 
with a GVWR over 10,000 lbs. are too stringent. 
Daimler-Benz stated that the requirements could 
only be met if the operative braking system has 
an increased capacity. 

In a late submission to the docket, Wagner 
Electric asserted that agency tests substan- 
tiating the capability to meet the partial system 
requirements for vehicles over 10,000 lbs. were 
based on the two most effective of the possible 
partial systems. The commenter stated that no 
data was provided on vertical split systems and 
suggested that the requirements as proposed 
would encourage forms of split systems, such as 
vertical split systems, that would inordinately in- 
crease the level of front brake torque (i.e., make 
the front brakes overly powerful) and contribute 
toward lock-up on icy or wet roads. (A vertical 



split system essentially consists of one sub- 
system that supplies braking power to the front 
brakes and another subsystem that provides 
power to the back brakes. This contrasts with a 
variety of other types of split systems. Some 
horizontal split systems, for example, consist of 
two subsystems that each provide some braking 
power to each wheel. The two types of split 
systems which Wagner Electric's comment sug- 
gested are the most effective are a horizontal 
split and a 1- Vz x V2 split, a system with some of 
the attributes of a horizontal split system.) A 
comment submitted by ATA also suggested that 
the requirements would mandate overly power- 
ful, aggressive front brakes. 

Several commenters suggested that the stop- 
ping distance requirements for vehicles over 
10,000 lbs. GVWR be relaxed. Wagner Electric 
suggested that the requirements currently in ef- 
fect for school buses be adopted. 

The partial system failure and failed power 
assist or brake power unit requirements were 
proposed by the agency after careful analysis of 
its own vehicle test results and of confidential 
data submitted by manufacturers. These data in- 
dicate that many production vehicles already 
meet the proposed requirements. The current 
school bus requirements were issued in 1975 
under a short-term statutory deadline. Analysis 
of current school bus data indicates that many 
school buses already meet the more stringent re- 
quirements proposed by the October 1979 notice. 
As with other stopping distance requirements, 
there is some increment of safety benefit for 
each reduction of stopping distance. When par- 
tial failure of the service brake system occurs or 
brake power or power assist units become in- 
operative, it is important that a vehicle be able to 
stop in a reasonable distance, especially when 
that vehicle has the aggressivity associated with 
a GVWR of over 10,000 lbs. 

In regard to Wagner Electric's comment con- 
cerning vertical split systems, it is true that if 
the subsystem providing power to the rear 
brakes in a vertical split system fails, the sub- 
system providing power to the front brakes 
would be required to meet the stopping distance 
requirements under the standard. Therefore, in 
order to meet this requirement with a vertical 
split system, a vehicle would need relatively 
powerful front brakes. Similar requirements 



PART 571; S 105-83-PRE 61 



have been in effect for vehicles with air brakes 
under Standard 121, and European regulations 
necessitate even more powerful front axle brakes 
without safety problems. 

Moreover, in keeping with the National Traffic 
and Motor Vehicle Safety Act, the requirements 
are written as performance requirements and not 
design requirements. Manufacturers may meet 
the requirements in many different ways and are 
not required to use vertical split systems. Indeed, 
the selection of a means of compliance that poses 
significant safety risks could raise a safety defect 
issue. If Wagner Electric is concerned that ver- 
tical split systems may contribute to lock-up 
when used on some vehicle configurations, the 
manufacturer has the option to use other types of 
split systems, such as horizontal splits, or a 
redundant split system. When one of the subsys- 
tems of a horizontal split system fails, some brak- 
ing power is still provided to each wheel by the 
operative subsystem, so the stopping distances 
do not have to be met solely by the power pro- 
vided to the front wheels. Therefore, the braking 
system does not have to have relatively powerful 
front brakes in order to meet the requirements. 
This would also be true for some other types of 
split systems and for redundant systems. 

Wagner Electric also stated that the 150 lb. 
maximum pedal force specified for the re- 
quirements is too low and might result in overly 
sensitive brakes. That company suggested that a 
200 lb. pedal force be adopted. 

An analysis of the data referred to above in- 
dicates that many vehicles on the road already 
meet this requirement, without experiencing 
problems of oversensitivity. While Wagner Elec- 
tric suggests in its comment that even a small 
person can reach a 200 lb. pedal effort, the agency 
has found that small females have difficulty even 
applying forces of less than 150 lbs. 

Moreover, when a driver is used to applying 
very little force to bring a vehicle to a stop, the 
driver is likely to believe that the braking system 
has failed entirely, rather than only partially, 
if the driver applies maximum force and cannot 
feel the vehicle braking. Reports of "no brakes" 
are sometimes given in accident reports where 
only a partial failure has occurred. Therefore, 
it is important that a vehicle's braking sys- 
tem respond noticeably when a driver is apply- 
ing significant force in a partial failure or 



failed power assist or brake power unit situation. 

A comment submitted by the Metropolitan 
Transit Agency of Dade County, Florida, called 
for lower pedal force requirements. That com- 
menter cited the difficulty smaller drivers have 
in bringing a large bus to a stop after loss of 
vacuum. In establishing the 150 lb. pedal force, 
the agency took account of both the need to 
establish a level of pedal force appropriate for 
smaller drivers and to keep it high enough that 
brakes will not be oversensitive in ordinary use. 
That commenter also suggested that the agency 
establish requirements for vacuum reserve. The 
agency included optional procedures in Standard 
105 that encourage manufacturers to include 
vacuum reserves by permitting slightly longer 
stopping distances in the no power tests if the 
vehicle has the capability of making several stops 
in consecutive order with gradually decreasing 
capabilities. The agency recognizes the safety ad- 
vantages offered by vacuum reserves, but has 
not, as of yet, proposed that they be required. 

A comment submitted by the Recreation Vehi- 
cle Industry Association (RVIA) requested that 
the test procedures for vehicles with a GVWR of 
over 10,000 lbs. be changed to require less stops 
and snubs to condition the brakes. The agency 
declines to make this change since a significant 
number of stops and snubs is required in order 
that a braking system's capability be tested in a 
"worn-in" condition. 

Equipment Integrity 

Comments on the requirements concerning 
equipment integrity were primarily limited to the 
spile stop requirements. RVIA suggested that 
the spike stop test requirements are inappro- 
priate for motor homes. According to RVIA, it is 
unaware of a single case where a weakness that 
the spike stop test would uncover has ever been 
found in a motor home. 

The spike stop test requirements were devel- 
oped to determine the structural integrity of a 
vehicle's braking system. Vehicles must be 
capable of making several very sudden stops 
without loss of brake system structural integrity. 
Virtually all types of vehicles, including motor 
homes, are at times subjected to the abuse caused 
by very sudden stops. If the vehicle's braking 
system loses its structural integrity during such 
stops, serious accidents could result. 



PART 571; S 105-83-PRE 62 



Parking Brakes 

The October 1979 notice proposed parking 
brake performance requirements designed to en- 
sure that vehicles have adequate grade holding 
performance. Under the proposal, vehicles with a 
GVWR of 10,000 lbs. or less are to meet these re- 
quirements on a grade of 30 percent, when a max- 
imum force of 90 lbs. is applied to hand-operated 
parking brake systems and 125 lbs. is applied to 
foot-operated parking brake systems. While no 
comments were received that were specifically 
opposed to the establishment of parking brake re- 
quirements for light trucks, several submissions 
did comment on the appropriateness of the 30 
percent gradient and the maximum force re- 
quirements. 

The Japan Automobile Manufacturers Associa- 
tion and Toyo Kogyo stated that a 30 percent gra- 
dient is too stringent. According to those com- 
ments, some vehicles have difficulty climbing a 30 
percent grade when fully loaded. They requested 
that a gradient of 18 percent be adopted, stating 
that European and Australian safety standards 
incorporate that requirement. 

The 30 percent gradient requirement, which is 
the same as that in effect for passenger cars and 
school buses with a GVWR of 10,000 lbs. or less, 
represents a degree of steepness that is found on 
roads in some parts of the United States. While 
the agency is unaware of any light trucks that 
cannot climb a 30 percent grade, even a vehicle 
that has difficulty climbing a 30 percent g^ade 
may on occasion be parked on such a steep hill. 
Moreover, recognizing the dangers inherent if a 
vehicle's grade holding performance is inade- 
quate, the agency established the requirements 
with a view toward providing a margin of safety 
for parking brake systems. The safety margin 
will prevent accidents from occurring when 
vehicles are parked on more commonly found 
grades, in some instances, where parking brake 
systems have deteriorated over time or are im- 
properly adjusted. It is also noted that although 
European regulations have only an 18 percent 
grade-holding requirement, those regulations 
also require a dynamic stopping performance test 
using the parking brake. 

Several commenters stated that the maximum 
force requirements proposed by the standard for 
vehicles with a GVWR of 10,000 lbs. or less are 



too stringent. Those commenters suggesting 
changes requested either that European re- 
quirements be followed (said to be 132 lbs. for 
hand-operated systems) or that current re- 
quirements for school buses be followed (125 lbs. 
for hand-operated systems and 150 lbs. for foot- 
operated systems). 

The 90 lb. and 125 lb. requirements proposed 
by the notice are the same as those in effect for 
passenger cars. They were chosen by the agency 
as the maximum force requirements that are ap- 
propriate for small females. Since small females 
may be expected to drive light trucks, it is ap- 
propriate to require that parking brake systems 
be designed with their needs in mind. Moreover, 
the agency established the 90 lb. and 125 lb. re- 
quirements with a recognition that some parking 
brake systems are located in positions within the 
vehicle which are awkward for drivers to reach. 
The 90 lb. and 125 lb. requirements therefore pro- 
vide a margin of safety for instances where 
drivers have difficulty applying adequate force to 
parking brake systems because of their location. 

As with the other requirements of the pro- 
posal, the agency established the parking brake 
requirements after conducting tests on produc- 
tion vehicles. Neither the agency's test results or 
any comments submitted indicate that manufac- 
turers will have difficulty meeting the parking 
brake requirements. 

Costs and Benefits 

The agency has considered the economic and 
other impacts of this final rule and determined 
that this rule is not significant within the mean- 
ing of Executive Order 12221 and the Department 
of Transportation's policies and procedures im- 
plementing that order. The agency's assessment 
of the benefits and economic consequences of this 
final rule are contained in a regulatory evaluation 
that has been placed in the docket for this rule- 
making. Copies of that regulatory evaluation can 
be obtained by writing NHTSA's docket section, 
at the address given in the beginning of this 
notice. 

The October 1979 notice explained that a regu- 
latory evaluation had been prepared before issu- 
ing the notice and had been included in the 
docket. A number of comments were received on 
the costs and benefits of the proposed re- 
quirements. 



PART 571; S 105-83-PRE 63 



Ford stated that although its cost analyses 
were not complete, it had sufficient information 
to indicate that the proposed requirements 
would affect a greater number of Ford products 
and cost considerably more than the agency had 
estimated. Chrysler stated that the requirements 
would necessitate the redesign of the parking 
brake systems on all of its light trucks and re- 
quire some degree of revision to master 
cylinders, brake boosters, and/or foundation 
brakes on 80 to 90 percent of its light trucks. 
That company also indicated that it would find it 
necessary to engage in considerably more testing 
than estimated by the agency in order to meet 
the proposed requirements. 

Both Ford and Chrysler suggested that several 
requirements be relaxed in order to reduce the 
costs of the proposed standard. Ford requested 
that first, second and fourth effectiveness test 
stopping distances be relaxed for all vehicles and 
that third effectivenss test stopping distances be 
relaxed for vehicles with a GVWR of 8,000 to 
10,000 lbs. Ford also requested that the stopping 
distance requirements for the failed system and 
spike stop check tests be relaxed and that the 
maximum parking brake force requirements be 
changed from 125 lbs. to 150 lbs. Chrysler asked 
that fourth effectiveness test stopping distances 
be extended by 16 percent and that the max- 
imum parking brake force requirements be 
changed from 125 lbs. to 150 lbs. 

General Motors stated that while it supported 
NHTSA action to require split service brake 
systems on vehicles over 10,000 lbs. GVWR, a 
considerably larger number of those vehicles 
would require changes than estimated by the 
agency. According to GM, optional split service 
brake systems were purchased on only two per- 
cent of its hydraulic braked heavy-duty vehicles 
in model year 1979. 

In order to aid in developing its cost estimates, 
the agency enlisted an outside contractor before 
issuing the October 1979 notice to conduct an in- 
dependent assessment of the costs that would be 
involved. A report prepared by the IIT Research 
Institute (IITRI), which was included in the 
docket, substantially verified the cost estimates 
made by NHTSA, with one exception. 

As the regulatory evaluation explained, 
estimates on the light truck brake system costs 
differed, reflecting the different methodologies 



used by IITRI and NHTSA. Since NHTSA's 
estimates were based on actual test results and 
confidential data submitted by the manufac- 
turers, which were unavailable to IITRI, the 
regulatory evaluation used NHTSA figures for 
light truck brake system costs. IITRI figures 
were used for development/compliance test costs 
and cost estimates for medium and heavy duty 
trucks. 

A revised regulatory evaluation, which has 
been placed in the docket, was prepared by the 
agency to accompany the issuance of this final 
rule. Revisions were made in the regulatory 
evaluation to reflect the latest information 
available to the agency. 

The comments by Ford and Chrysler were dif- 
ficult to evaluate since they gave only general- 
ized bases for their assertions that a greater 
number of vehicles would be affected by the 
standard than estimated by the agency. While 
those commenters cited some additional braking 
system components that might require changes, 
they did not specify which vehicles would require 
the changes or indicate what the costs of those 
changes would be. 

For example, while Chrysler asserted that the 
requirements would necessitate the redesign of 
the parking brake systems on all of its light 
trucks, it did not indicate its basis for believing 
that substantially more of its light trucks would 
require upgrading of their parking brake 
systems than estimated by the agency. Nor did it 
indicate what changes would be required or the 
costs of those changes. Ford stated that prelimi- 
nary test results indicate that the proposal would 
necessitate for some models, in addition to those 
changes assumed by the agency to be required, 
the addition of hydraulic boosters or larger 
hydraulic boosters and revisions to brake pedals, 
power steering pumps, hoses and tires. Ford did 
not indicate the nature of the preliminary test 
data it was relying upon. Nor did that commenter 
specify what models would require additional 
changes or indicate the costs of those changes. 
Also, while Ford requested numerous changes in 
the proposed requirements, it did not attempt to 
support the specific changes it requested. 

In light of the agency's own detailed evalua- 
tion of the changes made necessary by the re- 
quirements and of the costs of those changes, 
which was based upon test data and manufac- 



PART 571; S 105-83-PRE 64 



Parking Brakes 

The October 1979 notice proposed parking 
brake performance requirements designed to en- 
sure that vehicles have adequate grade holding 
performance. Under the proposal, vehicles with a 
GVWR of 10,000 lbs. or less are to meet these re- 
quirements on a grade of 30 percent, when a max- 
imum force of 90 lbs. is applied to hand-operated 
parking brake systems and 125 lbs. is applied to 
foot-operated parking brake systems. While no 
comments were received that were specifically 
opposed to the establishment of parking brake re- 
quirements for light trucks, several submissions 
did comment on the appropriateness of the 30 
percent gradient and the maximum force re- 
quirements. 

The Japan Automobile Manufacturers Associa- 
tion and Toyo Kogyo stated that a 30 percent gra- 
dient is too stringent. According to those com- 
ments, some vehicles have difficulty climbing a 30 
percent grade when fully loaded. They requested 
that a gradient of 18 percent be adopted, stating 
that European and Australian safety standards 
incorporate that requirement. 

The 30 percent gradient requirement, which is 
the same as that in effect for passenger cars and 
school buses with a GVWR of 10,000 lbs. or less, 
represents a degree of steepness that is found on 
roads in some parts of the United States. While 
the agency is unaware of any light trucks that 
cannot climb a 30 percent grade, even a vehicle 
that has difficulty climbing a 30 percent grade 
may on occasion be parked on such a steep hill. 
Moreover, recognizing the dangers inherent if a 
vehicle's grade holding performance is inade- 
quate, the agency established the requirements 
with a view toward providing a margin of safety 
for parking brake systems. The safety margin 
will prevent accidents from occurring when 
vehicles are parked on more commonly found 
grades, in some instances, where parking brake 
systems have deteriorated over time or are im- 
properly adjusted. It is also noted that although 
European regulations have only an 18 percent 
grade-holding requirement, those regulations 
also require a dynamic stopping performance test 
using the parking brake. 

Several commenters stated that the maximum 
force requirements proposed by the standard for 
vehicles with a GVWR of 10,000 lbs. or less are 



too stringent. Those commenters suggesting 
changes requested either that European re- 
quirements be followed (said to be 132 lbs. for 
hand-operated systems) or that current re- 
quirements for school buses be followed (125 lbs. 
for hand-operated systems and 150 lbs. for foot- 
operated systems). 

The 90 lb. and 125 lb. requirements proposed 
by the notice are the same as those in effect for 
passenger cars. They were chosen by the agency 
as the maximum force requirements that are ap- 
propriate for small females. Since small females 
may be expected to drive light trucks, it is ap- 
propriate to require that parking brake systems 
be designed with their needs in mind. Moreover, 
the agency established the 90 lb. and 125 lb. re- 
quirements with a recognition that some parking 
brake systems are located in positions within the 
vehicle which are awkward for drivers to reach. 
The 90 lb. and 125 lb. requirements therefore pro- 
vide a margin of safety for instances where 
drivers have difficulty applying adequate force to 
parking brake systems because of their location. 

As with the other requirements of the pro- 
posal, the agency established the parking brake 
requirements after conducting tests on produc- 
tion vehicles. Neither the agency's test results or 
any comments submitted indicate that manufac- 
turers will have difficulty meeting the parking 
brake requirements. 

Costs and Benefits 

The agency has considered the economic and 
other impacts of this final rule and determined 
that this rule is not significant within the mean- 
ing of Executive Order 12221 and the Department 
of Transportation's policies and procedures im- 
plementing that order. The agency's assessment 
of the benefits and economic consequences of this 
final rule are contained in a regulatory evaluation 
that has been placed in the docket for this rule- 
making. Copies of that regulatory evaluation can 
be obtained by writing NHTSA's docket section, 
at the address given in the beginning of this 
notice. 

The October 1979 notice explained that a regfu- 
latory evaluation had been prepared before issu- 
ing the notice and had been included in the 
docket. A number of comments were received on 
the costs and benefits of the proposed re- 
quirements. 



PART 571; S 105-83-PRE 63 



/ 



Ford stated that although its cost analyses 
were not complete, it had sufficient information 
to indicate that the proposed requirements 
would affect a greater number of Ford products 
and cost considerably more than the agency had 
estimated. Chrysler stated that the requirements 
would necessitate the redesign of the parking 
brake systems on all of its light trucks and re- 
quire some degree of revision to master 
cylinders, brake boosters, and/or foundation 
brakes on 80 to 90 percent of its light trucks. 
That company also indicated that it would find it 
necessary to engage in considerably more testing 
than estimated by the agency in order to meet 
the proposed requirements. 

Both Ford and Chrysler suggested that several 
requirements be relaxed in order to reduce the 
costs of the proposed standard. Ford requested 
that first, second and fourth effectiveness test 
stopping distances be relaxed for all vehicles and 
that third effectivenss test stopping distances be 
relaxed for vehicles with a GVWR of 8,000 to 
10,000 lbs. Ford also requested that the stopping 
distance requirements for the failed system and 
spike stop check tests be relaxed and that the 
maximum parking brake force requirements be 
changed from 125 lbs. to 150 lbs. Chrysler asked 
that fourth effectiveness test stopping distances 
be extended by 16 percent and that the max- 
imum parking brake force requirements be 
changed from 125 lbs. to 150 lbs. 

General Motors stated that while it supported 
NHTSA action to require split service brake 
systems on vehicles over 10,000 lbs. GVWR, a 
considerably larger number of those vehicles 
would require changes than estimated by the 
agency. According to GM, optional split service 
brake systems were purchased on only two per- 
cent of its hydraulic braked heavy-duty vehicles 
in model year 1979. 

In order to aid in developing its cost estimates, 
the agency enlisted an outside contractor before 
issuing the October 1979 notice to conduct an in- 
dependent assessment of the costs that would be 
involved. A report prepared by the IIT Research 
Institute (IITRI), which was included in the 
docket, substantially verified the cost estimates 
made by NHTSA, with one exception. 

As the regulatory evaluation explained, 
estimates on the light truck brake system costs 
differed, reflecting the different methodologies 



used by IITRI and NHTSA. Since NHTSA's 
estimates were based on actual test results and 
confidential data submitted by the manufac- 
turers, which were unavailable to IITRI, the 
regulatory evaluation used NHTSA figures for 
light truck brake system costs. IITRI figures 
were used for development/compliance test costs 
and cost estimates for medium and heavy duty 
trucks. 

A revised regulatory evaluation, which has 
been placed in the docket, was prepared by the 
agency to accompany the issuance of this final 
rule. Revisions were made in the regulatory 
evaluation to reflect the latest information 
available to the agency. 

The comments by Ford and Chrysler were dif- 
ficult to evaluate since they gave only general- 
ized bases for their assertions that a greater 
number of vehicles would be affected by the 
standard than estimated by the agency. While 
those commenters cited some additional braking 
system components that might require changes, 
they did not specify which vehicles would require 
the changes or indicate what the costs of those 
changes would be. 

For example, while Chrysler asserted that the 
requirements would necessitate the redesign of 
the parking brake systems on all of its light 
trucks, it did not indicate its basis for believing 
that substantially more of its light trucks would 
require upgrading of their parking brake 
systems than estimated by the agency. Nor did it 
indicate what changes would be required or the 
costs of those changes. Ford stated that prelimi- 
nary test results indicate that the proposal would 
necessitate for some models, in addition to those 
changes assumed by the agency to be required, 
the addition of hydraulic boosters or larger 
hydraulic boosters and revisions to brake pedals, 
power steering pumps, hoses and tires. Ford did 
not indicate the nature of the preliminary test 
data it was relying upon. Nor did that commenter 
specify what models would require additional 
changes or indicate the costs of those changes. 
Also, while Ford requested numerous changes in 
the proposed requirements, it did not attempt to 
support the specific changes it requested. 

In light of the agency's own detailed evalua- 
tion of the changes made necessary by the re- 
quirements and of the costs of those changes, 
which was based upon test data and manufac- 



PART 571; S 105-83-FRE 64 



turer-supplied information, as well as the inde- 
pendent assessment made by IITRI, the agency 
continues to believe that its cost estimates are 
correct, with one exception noted below. 

The agency did change the regulatory evalua- 
tion's estimate of the number of vehicles with a 
GVWR over 10,000 lbs. requiring split brake 
systems. The agency had anticipated that a 
greater percentage of those vehicles would be 
purchased with optional split brake systems. 
While the number of vehicles affected by that re- 
quirement is greater than originally estimated 
by the agency, the cost per vehicle remains the 
same, and the agency believes the requirements 
to be fully justified by the benefits that will 
accrue. 

Other comments that were received concern- 
ing costs related to costs of developing anti-lock 
or similar devices, such as brake system pressure 
modifiers, and cost that would be borne by final 
stage manufacturers. As explained fully above in 
the portion of this notice entitled "Effectiveness 
Requirements," manufacturers will not find it 
necessary to develop anti-lock or similar devices, 
nor will final stage manufacturers in most cases 
have any costs as a result of the standard. In- 
stead, final stage manufacturers will ordinarily 
be able to rely on the incomplete vehicle 
manufacturer's certification of the braking 
system. 

The October 1979 notice explained that the 
proposal was a continuation of prior NHTSA 
rulemaking on Standard 105. While the extension 
of Standard 105 to trucks, buses and MPV's had 
proceeded to the adoption of a final rule, that ex- 
tension was indefinitely delayed in April 1975 
because the agency had determined that 
although the benefits of the rule would be 
substantial, the costs of the standard, particu- 
larly for heavy trucks, warranted delaying the 
standard. See 40 FR 18411, April 28, 1975. 

Manufacturers have made a number of signifi- 
cant improvements in their braking systems 
since that time on a voluntary basis, largely 
following the requirements and test procedures 
of the delayed final rule. Because of those im- 
provements, as well as some changes made in the 
requirements by the agency, the costs of the 
standard today are only a small fraction of what 
they would have been in 1975. 

The April 1975 notice stated that manufac- 



turers had submitted costs for light to medium 
duty trucks that ranged from $54 to $775 per unit 
(depending on model configuration) to attain com- 
pliance with the standard. The agency compared 
those figures with independently gathered de- 
tailed cost information and substantiated that 
the manufacturers' estimates were accurate. In 
contrast to those figures, the agency today 
estimates that the average cost per domestic 
light truck, bus, or MPV with a GVWR of 10,000 
lbs. or less is only $2.71, or about $21.24 for each 
vehicle that needs to be upgraded in braking 
system performance. The costs for meeting the 
partial failure and warning indicator re- 
quirements for medium and heavy trucks (over 
10,000 lbs. GVWR) are estimated to be about $54 
per vehicle. The total costs of meeting the stand- 
ard's requirements for all trucks, buses and 
MPV's are estimated to be under $18 million. 

As explained elsewhere in this notice, the 
regulatory evaluation, and the October 1979 
notice, the agency carefully evaluated the costs 
and benefits of the proposed requirements. In 
analyzing costs, the agency estimated how the re- 
quirements would affect each manufacturer on a 
model-by-model basis. In light of this detailed 
analyis and evaluation, the agency declined to 
relax particular requirements on the sole ground 
that they would result in some costs to manufac- 
turers. 

A number of comments were also received that 
related to the benefits of the standard. Ford 
stated that the proposed requirements have not 
been justified as being the minimum necessary to 
provide safe operation of the affected vehicles. 
That commenter stated that the agency had not 
provided evidence that the levels of braking per- 
formance of today's vehicles are causative fac- 
tors in the accidents involving those vehicles. 

Ford also stated that the estimate of benefits 
presented in the agency's regulatory evaluation 
is based on inappropriate data and incomplete 
analysis. In particular, that commenter stated 
that a study by the Institute for Research in 
Public Safety (IRPS) that was cited by the 
regulatory evaluation does not support the con- 
clusion that a 5 to 10 percent reduction in ac- 
cidents could be obtained by a 5 percent shorten- 
ing of stopping distances. That study was based 
on a sample of skidding accidents, and the finding 
was related to the benefits that would accrue if 



PART 571; S 105-83-PRE 65 



vehicles were equipped with anti-lock braking 
systems. According to Ford, that finding does not 
relate to the effect on accidents that would be at- 
tributable to the implementation of the proposed 
requirements, since the requirements do not an- 
ticipate the introduction of anti-lock braking 
systems. That company also asserted that the 
relationship between measured vehicle param- 
eters such as specific stopping distances derived 
under specified test conditions and the safety ef- 
fectiveness of the same vehicle in customer serv- 
ice has yet to be established. 

A similar comment was submitted by NTEA. 
That commenter stated that by failing to demon- 
strate why an increase in light truck accident 
fatalities has occurred or that the proposed stand- 
ard will in any way reduce those fatalities, the 
NHTSA data are seriously deficient. NTEA also 
stated that since the requirements will affect only 
17 percent of the vehicles subject to the standard, 
NHTSA is obligated to identify that 17 percent 
segment as the cause of the safety problem. (As a 
result of the agency revising its estimate of the 
number of vehicles with a GVWR over 10,000 lbs. 
requiring the addition of split service brake 
systems, discussed above, the percentage of 
vehicles requiring changes as a result of the 
standard is now estimated to be about 20 
percent.) 

The October 1979 notice explained that in car- 
rying out the mandate of the National Traffic and 
Motor Vehicle Safety Act to issue vehicle safety 
standards to protect the public against unreason- 
able risk of vehicle accidents and of death or in- 
jury occurring as a result of such accidents, the 
agency is confronted with inherent problems that 
limit the degree of certainty and precision 
achievable in estimating the effectiveness and 
therefore benefits of proposed standards. While 
engineering and accident analyses can clearly 
demonstrate that certain vehicle improvements 
will facilitate the performance of the driver's task 
and thereby improve safety, it is virtually im- 
possible to isolate individual factors to arrive at 
precise and certain conclusions about the quan- 
tified benefits that will accrue. 

Given the duty to act in the area of accident 
avoidance notwithstanding an inherent measure 
of imprecision and uncertainty, the agency has 
developed and issued accident avoidance stand- 
ards while attempting within its capabilities to 



quantify the benefits of the standards and limit 
the uncertainty. The extension of Standard 105 is 
no different, and, given the inevitable residual 
uncertainty, the decisionmaking regarding the 
precise requirements rests in part on policy judg- 
ment. 

The braking system of a vehicle clearly pro- 
vides its most important accident avoidance 
capability. Common sense, as well as basic traffic 
theory, indicate that a vehicle with a shorter stop- 
ping distance capability will be safer than the 
same vehicle with a longer stopping distance 
capability, assuming that other parameters such 
as vehicle stability are held constant. Also, as 
noted above, since light trucks, buses, and MPV's 
share the same traffic flow as passenger cars, 
they should ideally have the same stopping 
distance capability. 

As fully explained above, the agency carefully 
evaluated the costs of improving braking systems 
for light trucks, buses and MPV's and proposed 
requirements that, in its judgment, were eco- 
nomical. In recognition of the costs and problems 
associated with anti-lock or similar devices, the 
agency proposed requirements that could be met, 
where upgrading was required, by simple, state- 
of-the-art changes to the types of braking 
systems in use. Since braking ability is an ex- 
tremely important safety factor and stopping 
distances can economically be made significantly 
shorter for light trucks, buses, and MPV's, the 
agency believes that the braking ability of those 
vehicles creates an unnecessary risk. 

Because available accident data and studies are 
limited, it is very difficult to make estimates as to 
the precise benefits that will result from improv- 
ing a vehicle's accident avoidance capability. The 
best information available to the agency in 
estimating the benefits resulting from improved 
stopping distances was the IRPS study, which 
was based on a survey of skidding accidents. Skid- 
ding accidents are useful for analysis because 
they leave physical evidence indicating the brak- 
ing distance of a vehicle prior to impact. Based 
upon that study, the agency concluded that a 5 to 
10 percent reduction of accidents could be ob- 
tained by a 5 percent shortening of stopping 
distances. 

The proposed requirements would result in a 
reduction of skidding accidents, despite the fact 
that anti-lock or similar devices are not con- 



PART 571; S 105-83-PRE 66 



templated, since some vehicles would have their 
braking balance improved. Also, with better 
braking capability, drivers might be less prone to 
applying their brakes in a manner that would 
result in skids. While the IRPS data may not be 
ideal, since it looked at some types of skidding 
accidents that would not be prevented by the re- 
quirements and did not look at some accidents 
that would be prevented (i.e., those that do not 
leave skid marks), the agency believes that it 
does provide evidence that is useful in analyzing 
all accidents where braking is attempted. 

The 105 test sequence was designed to simulate 
real world conditions. A vehicle's braking system 
is tested, for example, in new and broken-in condi- 
tions, at various speeds, while the vehicle is fully 
and lightly loaded, under varying conditions of 
fade, and under partial failure and failed power. 
Thus, the test does relate to performance in 
customer service. 

In deciding to propose the extension of Stand- 
ard 105 to light trucks, buses and MPV's, the 
agency was very concerned about the recent in- 
crease in light truck fatalities. However, the exten- 
sion is directed at all accidents and not merely at 
the increase in accidents as suggested by NTEA. 

As noted above, manufacturers have largely 
improved the braking performance of many of the 
vehicles subject to this standard since the final 
rule was delayed in 1975. Because of these im- 
provements, changes will be required in only 
about 20 percent of the vehicles subject to the 
standard. The only effect on the other 80 percent 
of vehicles is that manufacturers will not be able 
to reduce the performance of those vehicles' ex- 
isting braking systems. 

The agency believes it appropriate to require 
that manufacturers maintain the current level of 
braking performance for that 80 percent segment 
of vehicles. In the 1960's, for example, stopping 
distances of passenger cars lengthened as a result 
of increased weight. Today, the agency is con- 
cerned that manufacturers might reduce the 
braking ability of their vehicles as part of an ef- 
fort to improve fuel economy. Since some braking 
system components are relatively heavy, the 
braking system is a prime target for weight 
reduction. The agency believes braking ability to 
be such an important safety factor that it should 
not be compromised by efforts to improve fuel 
economy. 



Because of the limitations of available accident 
data, it is difficult and sometimes impossible to 
use available accident data to determine the acci- 
dent rates of particular vehicle types. As noted 
above, the agency believes the braking ability of 
those vehicles requiring upgrading of their brak- 
ing systems to create an unreasonable risk, since 
that ability can economically be significantly im- 
proved. 

Miscellaneous Comments 

The Japan Automobile Manufacturers Associa- 
tion stated that separate requirements should be 
applicable to vehicles used for passengers and 
those used for cargo. That request is similar to 
ones received during other rulemaking pro- 
ceedings to establish separate requirements for 
commercial applications. 

The National Traffic and Motor Vehicle Safety 
Act contemplates the application of standards 
based on vehicle type instead of vehicle use. Bas- 
ing a standard on vehicle use would present dif- 
ficult enforcement problems. It would also place a 
manufacturer in the difficult position of having to 
assess in advance the potential future use of the 
vehicle. Further, basing standards on vehicle use 
does not recognize that a vehicle may have two or 
more uses during its lifetime. Therefore, the 
agency has declined to establish separate re- 
quirements based upon vehicle use. 

The Japan Automobile Manufacturers Associa- 
tion also requested that all vehicles with a GVWR 
over 10,000 lbs., other than school buses, be in- 
cluded in Standard 130 under contemplation. 
Daimler-Benz also requested that vehicles over 
10,000 lbs. be included in one standard, whether 
they have air brakes or hydraulic brakes. Based 
upon the differences between air brake systems 
and hydraulic brake systems, the agency has 
issued separate standards for the two types of 
braking systems. Standard 121 currently applies 
to air braked vehicles and Standard 105 to 
hydraulic braked vehicles. 

The agency has issued an advance notice of pro- 
posed rulemaking for a new standard to apply to 
heavy duty brake systems. Standard 130, which 
addressed issues for which rulemaking is at least 
several years away. See 45 FR 13155, February 
28, 1980. A notice of proposed rulemaking, with 
opportunity to comment, would be issued if the 
agency decides to proceed with that standard. 



PART 571; S 105-83-PRE 67 



General Motors stated that the proposed re- 
quirements of Standard 105 may not be appro- 
priate for electric vehicles which are under 
development. Since these vehicles are still in the 
development stage, the agency is unable to 
establish at this time what types of changes, if 
any, would be appropriate for electric vehicles. 
The agency will consider the need for different 
requirements for electric vehicles when more in- 
formation is available as to what characteristics 
those vehicles will have. 

Wagner Electric requested that the weight 
permitted for driver and instrumentation on 
vehicles with a GVWR of 10,000 lbs. or less for the 
lightly loaded tests be increased from 300 lbs. to 
400 lbs. to permit the use of more recording 
equipment. Since the lightly loaded tests measure 
the braking ability of a vehicle while unloaded, it 
is desirable to keep the weight as low as possible. 
However, after evaluating the types of in- 
strumentation that are used to certify compliance 
with Standard 105, the agency agrees that in- 
creasing the weight allowance for driver and in- 
strumentation from 300 lbs. to 400 lbs. for 
vehicles with a GVWR of 10,000 lbs. or less will 
allow the use of additional types of instrumenta- 
tion that will be useful in evaluating the perform- 
ance of a vehicle's braking system. Moreover, the 
agency has determined that the slight increase in 
weight will not adversely affect the results of the 
lightly loaded tests. 

One commenter suggested that the standard's 
requirements might have an adverse effect on 
tire manufacturers, since tires are an important 
parameter in complying with the standard and 
manufacturers would not have the time, funds or 
facilities to test every kind of tire. Manufacturers 
will not be required to test all kinds of tires, since 
they purchase tires according to specifications. 
Normal production tires were used in all tests 
relied on by the agency in establising the stand- 
ard's requirements. The standard has been in ef- 



fect for several years for passenger cars and 
school buses without adverse effects on tire 
manufacturers. 

Leadtime 

Numerous comments were received on the pro- 
posed effective date of the requirements. The 
agency evaluated those comments and agrees 
with a number of them that a minimum of 2 years 
leadtime is appropriate. The effective date of the 
standard was changed to September 1, 1983, 
which gives a leadtime well in excess of 2 years 
and corresponds with the start of a new model 
year. 

Chrysler stated that it required a leadtime of 
30 months if its recommendations were adopted 
and 42 months if its recommendations were not 
adopted. The extra 12 months beyond 30 months 
were said to be needed to develop load-sensing or 
deceleration-sensing proportioning valves. As ex- 
plained fully in this notice, no manufacturer will 
be required to develop anti-lock or similar devices 
in order to be able to comply with the standard's 
requirements. The effective date of this final rule 
gives a leadtime of approximately 30 months. 

The principal authors of this notice are George 
L. Parker, Office of Vehicle Safety Standards, and 
J. Edward Glancy, Office of Chief Counsel. 

In consideration of the foregoing, §571.105, 
Chapter V of Title 49, Code of Federal Regula- 
tions, is amended accordingly. 

Issued on December 22, 1980. 



Joan Claybrook 
Administrator 

46 FR 55 
January 2, 1981 



PART 571; S 105-83-PRE 68 



PREAMBLE TO AN AMENDMENT TO 
FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 105 

Hydraulic Brake Systems 

(Docket No. 70-27; Notice 23) 



ACTION: Final rule; response to petitions 
for reconsideration. 

SUMMARY: This notice responds to three 
petitions for reconsideration concerning the 
amendment extending Standard No. 105, 
Hydraulic Brake Systems, to trucks, buses, 
and multipurpose passenger vehicles 
(MPV's). The amendment also upgraded the 
standard's requirements for school buses. In 
response to one of the petitions, the agency 
has changed the parking brake gradient 
requirement from 30 percent to 20 percent 
for trucks, buses (other than school buses) 
and MPV's with a GVWR of 10,000 pounds or 
less. The agency will shortly propose a 
conforming amendment to make the same 
change for school buses with a GVWR of 
10,000 pounds or less. 

DATES: This amendment is effective 
September 1, 1983. That is the same effective 
date as for the January 1981 final rule 
extending Standard No. 105 to trucks, buses 
and MPV's. 

ADDRESS: Petitions for reconsideration 
should refer to the docket number and be 
submitted to: Docket Section, Room 5109, 400 
Seventh Street, S.W., Washington, D.C. 
20590. 

SUPPLEMENTARY INFORMATION: On 
January 2, 1981, the NHTSA published in the 
Federal Register (46 F.R. 55) a final rule 
amending Standard No. 105, Hydraulic Brake 
Systems. Prior to that time, the standard 



applied to passenger cars and school buses 
only. The amendment extended the standard's 
applicability on a general basis (with some 
modifications) to trucks, all types of buses, 
and multipurpose passenger vehicles (MPV's) 
with a gross vehicle weight rating (GVWR) of 
10,000 pounds or less. (These vehicles are 
collectively referred to as LTM's.) Several 
requirements were also extended to trucks, 
buses and MPV's with a GVWR greater than 
10,000 pounds. In addition, the standard's 
requirements for school buses were upgraded. 
Petitions for reconsideration were filed 
with the agency by Chrysler, Ford and the 
Brake System Parts Manufacturers Council, 
all of which dealt almost entirely with the 
requirements applicable to vehicles with a 
GVWR of 10,000 pounds or less. Of the three 
petitions, Chrysler's was the only one that 
raised any technical issues associated with 
compliance with the amendment. All three 
petitions challenged the amendment on the 
bases of safety need and/or costs and 
benefits. After carefully evaluating those 
petitions, the agency decided to modify the 
parking brake requirements in response to 
Chrysler's petition. To the extent set forth 
below, Chrysler's petition is granted. 
Otherwise, Chrysler's petition and the other 
two petitions are denied. 

Parking Brake Requirements 

Standard No. 105 includes requirements 
for both a vehicle's service brake system and 
its parking brake. These two systems are 
related in that the parking brake uses major 



PART 571; S 105-83-PRE 69 



components of the service brake system, 
including the brake shoes and brake drums. 
The final rule's parking brake requirements 
specified that various performance tests be 
met when a vehicle is parked on a 30 percent 
grade and a maximum force of 90 pounds is 
applied to hand-operated parking brake 
systems and 125 pounds is applied to foot- 
operated parking brake systems. 

Chrysler's petition for reconsideration 
stated that the parking brake effort limits 
would cause a major redesign of most of its 
brake systems. According to that company, 
such redesign would waste scarce resources 
and be inflationary in the absence of 
demonstrated benefits. 

The agency contacted Chrysler to obtain 
clarification of that company's assertions. 
The agency requested information about the 
nature of the changes needed to meet the 
parking brake requirements and the costs of 
those changes, as well as data substantiating 
those needs. Chrysler indicated that all of its 
parking brake systems would require changes 
in order to meet the parking brake 
requirements. Many vehicles were said to 
require a major redesign, including new 
actuating pedals and supporting structures, 
low friction cables with new guides, new 
parking brake lever arms within the rear 
brake drums, and new shoes and linings. 

Chrysler's assertions were substantiated 
by test data. Chrysler ran a series of parking 
brake tests on a cross-section of its light 
trucks on both a 32 percent grade and a 20 
percent grade. (The 32 percent grade was 
used because it was the grade closest to 30 
percent that Chrysler had available.) Of nine 
vehicles tested on the 32 percent grade, only 
one passed the parking brake tests. That 
vehicle passed by a margin generally 
considered to be insufficient to assure that 
other vehicles of the same type would pass 
the tests. 

In addition to the information received 
from Chrysler, the agency received new data 
from agency-sponsored tests that were 
conducted for purposes unrelated to this 
rulemaking. Three Chrysler LTM's were 
among the vehicles tested. While the tests 
were limited in number, their results 



confirmed the information supplied by 
Chrysler. Both the data submitted by 
Chrysler and the test results received from 
the agency-sponsored tests have been placed 
in the docket. 

The agency evaluated Chrysler's assertions 
in light of the test data received. Based upon 
that data, the agency has concluded that its 
Regulatory Evaluation underestimated the 
costs of the parking brake requirements for 
Chrysler. Because this conclusion is based on 
actual test results, it is more reliable than the 
original conclusions made in the Regulatory 
Evaluation. Those earlier conclusions were 
largely based on engineering analysis, which 
is generally less reliable than actual testing. 
While they were also based on confidential 
information received from manufacturers, 
the agency had received less information 
from Chrysler than from other companies. 

The Regulatory Evaluation estimated that 
10 percent of Chrysler's LTM's would require 
changes in order to meet the parking brake 
requirements, at an average cost of $10.00 
per vehicle needing changes. The agency now 
estimates that virtually all of Chrysler's 
LTM's would require changes in order to 
meet the parking brake requirements as 
issued. Many of Chrysler's LTM's would 
require a minor redesign with the types of 
changes indicated by Chrysler and listed 
above. Other vehicles would require a minor 
redesign, with such changes as longer 
actuating pedals, rerouted cables, and new 
parking brake lever arms within the rear 
brake drums. 

Chrysler did not provide information about 
the costs of the changes needed to meet the 
parking brake requirements. The agency 
estimates that the cost per vehicle requiring 
a major redesign would be $17.50, while the 
cost per vehicle requiring a minor redesign 
would be $6.00. These estimates are based on 
the types of changes needed for a major 
redesign and a minor redesign, discussed 
above. The agency used brake system 
component costs contained in a report 
prepared by the IIT Research Institute under 
contract to the agency, for guidance in 
preparing its estimates. That report, which 
was issued in 1979, was included in the docket 



PART 571; S 105-83-PRE 70 



at the time the notice of proposed rulemaking 
was issued. 

In response to Chrysler's petition for 
reconsideration, the agency reevaluated 
Standard No. 105's parking brake requirements 
in light of the higher costs that it recognizes 
would result from those requirements. In 
reevaluating the requirements the agency 
analyzed two issues: the appropriateness of 
the parking brake effort limits and the 30 
percent gradient. Concerns about both of 
these issues were raised by several 
commenters in response to the notice of 
proposed rulemaking. 

While the parking brake effort limit and 
gfradient requirements address different 
issues from the point of view of motor vehicle 
safety, in practice the two requirements are 
closely related. Over a certain range of both 
force and gradient, a given parking brake will 
hold a vehicle on increasingly steep gradients 
as increasingly greater force is applied to the 
brake. Thus, a given parking brake design 
may be able to meet either a more stringent 
parking brake effort limit (i.e., a limit 
requiring that less force be used) or a steeper 
gradient, but not both. 

The agency has concluded, in light of the 
lack of significant safety need for a gradient 
requirement as stringent as 30 degrees and 
the increased costs that would result from 
the parking brake requirements, that the 
parking brake gradient requirement should 
be changed from 30 percent down to 20 
percent with retention of the parking brake 
effort limits. As explained below, this change 
will substantially reduce the costs of the 
parking brake requirements with only a 
minimal impact on benefits. Also, the change 
may promote international harmonization of 
safety standards. Consideration is currently 
being given in Europe to changing its 
standard to incorporate a 20 percent gradient 
requirement instead of an 18 percent 
gradient. 

The preamble to the final rule explained 
that two commenters had indicated that they 
believed the 30 percent gradient to be too 
stringent. Those commenters requested that 
an 18 percent gradient be adopted, noting 
that European and Australian safety 



standards incorporate that gradient. The 
agency declined to adopt a less stringent 
gradient at that time, noting that 30 percent 
gradients do exist in some parts of the United 
States and that the requirement provided a 
margin of safety where parking brake 
systems have deteriorated over time or are 
improperly adjusted. Even at that time, the 
agency recognized that any benefits of that 
particular requirement would be relatively 
small. Roads with a gradient as steep as 30 
percent exist in only a few parts of the 
country. Therefore, only a small number of 
vehicles affected by this standard would ever 
encounter such roads. 

The agency does not believe that the large 
numbers of vehicles affected by the standard 
should be required to meet this particular 
requirement which would only be of any 
possible benefit for a very small number of 
vehicles. 

The agency declined to change the parking 
brake effort requirements because they were 
chosen as the maximum force requirements 
that are appropriate for small females. Those 
requirements, a maximum force of 90 pounds 
for hand-operated parking brake systems and 
125 pounds for foot-operated parking brake 
systems, are the same as those in effect for 
passenger cars. Chrysler's comment on the 
notice of proposed rulemaking had asked that 
they be changed to 125 pounds and 150 
pounds, respectively. Those limits represent 
the parking brake effort requirements that 
have been in effect for school buses for 
several years. Research studies indicate, 
however, that between 20 and 50 percent of 
the female driving population do not have 
enough strength to exert the maximum pedal 
efforts that have been permitted for school 
buses. It is appropriate to require that 
parking brake systems be designed with the 
needs of the driving population in mind. The 
90 pound and 125 pound limits will cut the 
above percentages in half, i.e., only 10 
percent to 25 percent of the females may lack 
sufficient strength. 

The new parking brake effort limits apply 
to all LTM's, including school buses (with a 
GVWR of 10,000 pounds or less). As noted 
above, school buses were subject to Standard 



PART 571; S 105-83-PRE 71 



No. 105 before the January 1981 final rule 
was issued. The parking brake requirements 
for school buses with a GVWR over 10,000 
pounds, which specify both a 20 percent 
gradient and the less stringent effort limit, 
were not changed by either the Jari'eary 1981 
final rule or this amendment. However, the 
January 1981 final rule did change the 
standard's parking brake requirements for 
school buses with a GVWR of 10,000 pounds 
or less to include the new more stringent 
effort limit. The agency had not proposed 
changing the gradient requirement, which 
remained at 30 percent. 

As a conforming amendment, the agency 
will shortly propose to change the gradient 
requirement for school buses with a GVWR 
of 10,000 pounds or less from 30 percent to 20 
percent. The purpose of that change would be 
to make the parking brake requirements for 
those school buses the same as for other 
LTM's. The agency believes that change 
should be made primarily because school 
buses are constructed on the same chassis, 
including parking brakes, as other LTM's. 
Different parking brake requirements for 
school buses could either limit which chassis 
could be used for school buses or require.that 
new parking brake systems be specifically 
designed and installed on some of those 
chassis used for school buses. In light of the 
more stringent parking brake effort limits 
and the relationship between force and the 
steepness of gradient on which a parking 
brake will hold a vehicle, the agency does not 
believe that current school bus parking 
brakes will be significantly altered as a result 
of the less stringent gradient requirement. 

The agency has determined that significant 
cost savings will result from changing the 
gradient requirement for all LTM's. With a 
30 percent gradient requirement, Chrysler 
would be required to complete major 
redesigns of the braking systems of many of 
its vehicles and minor redesigns of the rest. 
With the 20 percent gradient requirement, 
Chrysler will not have to complete any major 
redesigns. The agency estimates that 
Chrysler will have to complete minor 
redesigns on approximately 48 percent of its 
vehicles. 



A Supplement to the Final Regulatory 
Evaluation has been prepared to reflect these 
new conclusions and has been placed in the 
docket. The figures contained in that 
document assume that the conforming 
amendment for school buses, discussed 
above, will be made. If it is not made, 
substantially higher costs for school buses 
could be involved. Because of the larger 
number of vehicles that are now estimated to 
be affected, the new projected cost for 
parking brake requirements for Chryser is 
higher than previously estimated, despite the 
relaxation of the gradient requirement. The 
Supplement to the Final Regulatory 
Evaluation estimates that the parking brake 
requirements will result in a total cost to 
Chrysler of $1,271,400. The previous estimate 
was $442,000. The agency now estimates that 
the total costs of the parking brake 
requirements for Chrysler would have been 
in excess of $3,000,000 if the gradient 
requirement was left at 30 percent. 

While the agency now estimates that the 
20 percent grade will result in greater costs 
for Chrysler (though not for manufacturers 
as a whole) than originally estimated, the 
agency believes that those costs are justified. 
The parking brake of a vehicle performs an 
important safety function. It is vital that a 
vehicle's parking brake be able to hold the 
vehicle on the types of grades on which it is 
parked. Twenty percent grades are not 
uncommon in urban and residential areas, 
both on streets and driveways, where these 
vehicles are likely to be parked. In light of the 
relatively modest cost required to meet the 
20 percent grade requirement, the agency 
has determined that vehicles not meeting 
that requirement pose an unreasonable safety 
risk. As noted above. Standard No. 105 has 
required even large school buses, i.e., those 
with a GVWR greater than 10,000 pounds, to 
be tested on a 20 percent grade for several 
years. Also, Standard No. 121, Air Brake 
Systems, uses a 20 percent grade for large 
air-braked trucks. 

The change in gradient will result in cost 
savings to other manufacturers. The agency's 
new cost estimates for those manufacturers 
are set forth in the Supplement to the Final 



PART 571; S 105-83-PRE 72 



Regulatory Evaluation. Th^ agency estimates 
that while the number of vehicles requiring 
upgrading as a result of the parking brake 
requirements will not change for those 
manufacturers, less significant design 
changes will be needed to meet the new 
gradient requirement. The costs for those 
manufacturers will therefore be less than 
previously estimated. 

Service Brake Requirements: Technical Issues 

Chrysler's petition discussed several 
issues in addition to the parking brake 
requirements and requested withdrawal of 
the entire amendment pending further studies. 
That company stated, as it did in its comment 
on the notice of proposed rulemaking, that 
the test requirements are overly stringent 
and unreasonable because the test 
procedures are abusive to the brake system. 
According to that commenter, the test 
procedure is unrepresentative of real-world 
driving conditions and goes beyond the need 
for motor vehicle safety. Moreover, that 
commenter suggested that the requirements 
might cause manufacturers to bias the design 
of brake systems toward complying with the 
standard rather than providing brake 
systems that are balanced under all vehicle 
loading and driving conditions. 

The agency carefully considered and 
addressed those concerns in the preamble to 
the January 1981 final rule. Chrysler's 
petition neither addressed the statements 
made by the agency in response to those 
concerns nor indicated any consideration of 
changes made in the standard's requirements 
to assure that manufacturers have adequate 
leeway to produce well-balanced brake 
systems. The petition also did not cite any 
new issues or data related to those concerns. 
Moreover, as explained in the preamble to 
the final rule, the vast majority of light 
trucks sold today already meet all of the 
standard's performance requirements 
without experiencing any problems relating 
to the balancing of brake performance. 

Standard No. 105's test procedures were 
developed by the agency to assure that a 
vehicle's braking system meets minimum 



performance requirements under the varying 
types of conditions experienced in actual 
service. A vehicle's braking system is tested, 
for example, in new and broken-in conditions, 
at various speeds, while the vehicle is fully 
and lightly loaded, under varying conditions 
of fade, and under partial failure and failed 
power. 

Contrary to the assertions made by 
Chrysler's petition and as explained in the 
preamble to the final rule, the tests do 
represent the types of conditions 
experienced in actual service. For example, 
the standard's second fade test, which 
Chrysler has alleged in the past to be 
abusive, simulates the type of fade 
experienced during long mountain descents. 
The agency has verified that the 
temperatures produced by the test sequence 
are the same temperatures as sometimes 
experienced during long mountain descents. 

Chrysler's comment on the proposed rule 
requested only one change in the standard's 
requirements based upon the above-stated 
concerns, an increase of 16 percent in fourth 
effectiveness (fully loaded) stopping 
distances. Chrysler stated that change was 
necessary to provide consumers with better 
balanced brake systems and to avoid the use 
of unproven load or deceleration sensing 
proportioning devices. As the preamble to 
the final rule explained, the proposed 
stopping distances were based on vehicle 
tests conducted by the agency using 
production vehicles with unaltered brakes 
and on confidential information provided by 
General Motors, Ford and Chrysler. These 
data indicated that recent models of almost 
all vehicles under 8,000 pounds GVWR 
passed the proposed requirements. 
Moreover, the agency determined that all 
vehicles subject to the standard could meet 
the proposed requirements without using 
unproven load or deceleration sensing 
proportioning devices by instead making 
modifications to such vehicle components a& 
brake linings, wheel cylinders, master 
cylinders, and combination valves. 

A vehicle's braking system which met the 
proposed requirements for Standard No. 105 
would be adequately balanced in that it would 



PART 571; S 105-83-PRE 73 



meet performance requirements uiider the 
varying conditions described above, most 
significantly when the vehicle was both 
loaded and unloaded. Based upon a number of 
comments received from manufacturers, 
however, as well as on a further evaluation of 
available data, the agency determined for the 
January 1981 final rule that the stopping 
distances for the fourth effectiveness test for 
vehicles with a GVWR of 8,000 to 10,000 
pounds should be extended by 10 percent. 
This change gave manufacturers additional 
leeway in balancing their braking systems, 
thus making it easier to design systems that 
are balanced for both fully loaded and lightly 
loaded conditions. 

The preamble to the final rule explained 
that since the agency had concluded that the 
requirements could be met as proposed for all 
vehicles (for both loaded and unloaded tests) 
without anti-lock or similar devices, the 
agency declined to adopt Chrysler's 
suggestion of a 16 percent extension of fourth 
effectiveness stopping distances. Instead, 
NHTSA chose the 10 percent extension 
suggested by a number of other manufacturers. 
The agency further determined, based on 
test data, that a 10 percent extension would 
be sufficient to make it easier for 
manufacturers to assure that their vehicle's 
braking systems perform well in both loaded 
and unloaded conditions. 

Neither Chrysler's comment on the notice 
of proposed rulemaking or its petition for 
reconsideration explained the derivation of 
its 16 percent figure. Moreover, Chrysler's 
petition for reconsideration did not indicate 
why the 10 percent extension was insufficient 
to meet the problem identified by Chrysler 
and did not either renew that company's 
request for a 16 percent extension, or raise 
any other issues concerning the matter. 

Safety Need, Costs and Benefits 

All three petitions for reconsideration 
challenged the extension of the standard on 
the bases of safety need and/or costs and 
benefits. Chrysler stated that the January 
1981 final rule would require it and probably 
other manufacturers to redesign service and 



parking brake systems of light duty trucks, 
buses and MPV's. According to that 
commenter, such changes would waste scarce 
resources in the absence of any demonstrated 
safety need. As explained above, the agency 
changed the parking brake requirements in 
response to Chrysler's concerns. Ford's 
petition requested withdrawal of the entire 
final rule because it believes there has been a 
complete lack of any valid demonstration by 
NHTSA that the implementation of the 
requirements may reasonably be expected to 
produce the safety benefits that have been 
projected for it and because it believes that 
the expenditures required to demonstrate 
conformity with the standard are excessive 
and inflationary. Ford's petition also stated 
that NHTSA has failed, based on data 
presented, to establish a safety need for the 
extension of the standard. The Brake System 
Parts Manufacturers Council stated in its 
petition that it did not believe that careful 
analysis has been conducted relating to the 
costs and benefits of the standard and that it 
does not believe that regulations should be 
adopted unless the benefits exceed the costs 
of the regulation. 

The issues of safety need and costs and 
benefits were discussed at considerable 
length in the preambles of the notice of 
proposed rulemaking and the final rule and in 
the Regulatory Evaluation which was 
prepared by the agency and made available 
to the public. As those documents indicate, 
the agency did carefully consider those 
issues. 

The safety need for the extension of the 
standard arises from the vital safety role 
played by a vehicle's braking system and the 
fact that many vehicles are produced with 
braking systems which can be significantly 
improved at an economical cost. In evaluating 
safety need, the agency carefully considered 
studies indicating the number and 
seriousness of accidents involving these 
vehicles, the overinvolvement of LTM's in 
fatal accidents as compared with passenger 
cars, the reduction in accidents that would 
result from improved braking systems, and 
the costs and feasibility of making such 
improvements. 



PART 571; S 105-83-PRE 74 



One of the agency's primary concerns 
about LTM braking is the differential in 
stopping distances between passenger cars 
and LTM's. Since light trucks, buses and 
MPV's share the same roads and traffic flow 
with passenger cars, they should ideally stop 
in the same distances. The preamble to the 
final rule explained, however, that there are 
differences between passenger cars and 
LTM's which make accomplishing that goal 
more difficult for LTM's. Therefore, taking 
those differences into account, the agency 
established stopping distances for light 
trucks, buses and MPV's which are slightly 
longer than those in effect for passenger cars. 
In light of the greater aggfressiveness 
associated with LTM's as a result of their 
size, weight, and design, the agency 
determined that there is a safety need for 
LTM braking to be as optimal as is 
economically feasible, thereby reducing the 
differential in stopping distances between 
passenger cars and LTM's and reducing 
accidents involving those vehicles. 

Based on those considerations, the agency 
believes there is a safety need to assure that 
the braking performance of all vehicles 
subject to the standard is at the optimal level 
which can economically be achieved. 
Approximately 25 percent of the vehicles 
subject to the amendment will require 
improved braking systems. Moreover, the 
rulemaking action has had and will continue 
to have an effect on the other 75 percent of 
vehicles. As is explained belpw, manufacturers 
have already improved the braking systems 
of many of their vehicles, largely as a result 
of this rulemaking. 

The agency believes there is a safely need 
to assure that those vehicles' braking 
performance is not downgraded. Increases in 
stopping distance are not without precedent. 
Stopping distances for passenger cars 
actually lengthened during the 1960's as a 
result of increased weight. Today, the agency 
is concerned that manufacturers might be 
tempted, in the absence of a standard, to 
reduce the braking performance of their 
vehicles as part of an effort to reduce weight 
and thereby improve fuel economy. Since 
some braking system components are 



relatively heavy, the braking system js a 
prime target for weight-reduction. The 
agency believes braking ability to be such an 
important safety factor that it should not be 
compromised by efforts to improve fuel 
economy. 

Contrary to assumptions made by Ford's 
petition for reconsideration, the agency did 
not issue the amendment to Standard No. 105 
solely because of the overinvolvement of 
LTM's in fatal accidents, as compared to 
passenger cars, and the rise in the trend of 
those accidents. Ford attempted to 
demonstrate in its petition that the 
overinvolvement of LTM's in fatal accidents 
is the result of a greater number of young 
males driving those vehicles rather than a 
problem with LTM braking ability. Ford also 
argued that there is no evidence that 
improved braking ability for LTM's will 
reverse the rise in the trend of fatal accidents 
involving those vehicles. 

The agency included in its Regulatory 
Evaluation an analysis of accident data 
involving LTM's. The agency stated that the 
overinvolvement of LTM's in fatal accidents 
suggests a probability that LTM's are 
deficient in accident preventative systems 
and/or that their weight and aggressiveness 
make them dangerous to pedestrians, 
bicyclists, and occupants of lower weight 
cars. The Regulatory Evaluation noted that 
in either case improvement of the braking 
systems of LTM's for greater accident 
prevention would serve to help fulfill the 
need for safety. 

Ford may be correct that the demographic 
profile of LTM drivers is another factor 
accounting for the overinvolvement of LTM's 
in fatal accidents. That would not change the 
fact that improved braking ability will reduce 
accidents. Similarly, the fact that the rise in 
the trend of fatal accidents involving LTM's 
has occurred during a period when brakirfg 
performance has either improved or been 
held constant does not alter the fact that 
further improvements in braking 
performance will produce additional safety 
benefits. There is a safety need for vehicles' 
braking systems to perform as optimally as is 
economically feasible. The agency has not 



PART 571; S 105-83-PRE 75 



claimed that improved braking performance 
will by itself reverse the rise in the trend of 
fatal accidents involving LTM's. The agency 
has determined that improved braking 
performance as a result of the amendment 
will reduce accidents that would occur in the 
absence of the standard and thereby save 
lives. _ 

The amendment to Standard No. 105 was 
issued by the agency in light of the total 
number of accidents involving LTM's and not 
just the increase in those accidents. As noted 
above, the agency evaluated the number and 
seriousness of accidents involving LTM's, the 
overinvolvement of LTM's in fatal accidents 
as compared with passenger cars, the 
reduction in accidents that would result from 
improved braking systems, and the costs and 
feasibility of making such improvements. 
Before issuing the notice of proposed 
rulemaking, the agency estimated both the 
costs and the benefits of the requirements and 
concluded that the costs of the amendment 
were justified by the benefits. Based upon all 
of these factors, the agency concluded that 
improving braking systems is a reasonable 
way of reducing some of the LTM accident 
problem. 

The rulemaking process for this 
amendment has been going on for a period of 
over 10 years. During the early 1970's, a final 
rule was issued establishing braking 
requirements for these vehicles. However, 
that rule was indefinitely delayed in 1975 
based upon economic considerations. Since 
that time, manufacturers have voluntarily 
made a number of improvements in their 
braking systems, largely following the 
requirements and test procedures of the 
delayed final rule. 

Because of the voluntary changes made by 
manufacturers in many of their vehicles since 
the previous final rule was delayed, as well as 
changes made by the agency in the new 
standard, the costs of the amendment are 
estimated to be only a small fraction of those 
of the delayed 1975 final rule. Manufacturers 
had submitted costs for the 1975 final rule for 
light to medium duty trucks that ranged from 
$54 to $775 per unit (depending on model 
configuration) to attain compliance with the 



standard. The agency compared those figures 
with independently gathered detailed cost 
information and determined that those 
estimates were accurate. 

Those figures have no relevance to the 
January 1981 final rule. Today, as a result of 
the voluntary changes made by manufacturers 
in many of their vehicles and changes made in 
the standard's requirements by the agency, it 
is estimated that the average cost of the new 
final rule will be only $2.53 per domestic 
LTM, or about $13.74 for each vehicle that 
needs to be upgraded. The costs for meeting 
the requirements for medium and heavy 
trucks (over 10,000 lbs GVWR) are estimated 
to be about $54 per vehicle. The total costs of 
meeting the standard's requirements for all 
trucks, buses and MPV's are estimated to be 
under $18,000,000. 

The agency made its estimates of costs on a 
company-by-company basis. In order to assure 
that its estimates were correct, the agency 
enlisted an outside contractor to independently 
assess the costs that would be involved. As 
the preamble to the January 1981 final rule 
explained more fully, the report substantially 
verified the cost estimates of the agency. Both 
the contractor's report and the agency's 
Regulatory Evaluation, which were available 
to the public in the docket, indicated the 
models which would require upgrading and 
the nature of the changes needed. 

Comments received from Ford and 
Chrysler on the notice of proposed 
rulemaking suggested that a greater number 
of vehicles would be affected by the standard 
than estimated by the agency. However, 
those comments gave only generalized bases 
for that assertion. While those commenters 
cited some additional braking system 
components that might require changes, they 
did not specify which vehicles would require 
changes or indicate what the nature or costs 
of those changes would be. Neither 
Chrysler's petition for reconsideration or 
that of Ford provided such information. 

The agency contacted Chrysler to obtain 
clarification of that company's assertions 
about the costs of the standard. As explained 
above, Chrysler provided information 
concerning changes that would be required as 



PART 571; S 105-83-PRE 76 



a result of the parking brake requirements. 
That company also provided test data to 
substantiate that information. Largely on the 
basis of that information, the agency changed 
the parking brake requirements and amended 
its cost estimates concerning those 
requirements. Chrysler did not provide 
information concerning the costs of the other 
requirements of the standard. In the absence 
of information contradicting the detailed 
studies on costs made by both the agency and 
an outside contractor for those other 
requirements, the agency continues to 
believe that its cost estimates are correct. 

The agency also contacted Ford to obtain 
clarification of its assertions about costs. 
Ford's petition stated that the amendment 
would result in $10,000,000 of certification 
related costs for that company and cause it to 
raise the suggested retail prices of its LTM's 
by an average of $11 per vehicle. By contrast, 
the agency's estimate of certification costs 
for Ford is only $130,000. Ford did not discuss 
the $130,000 figure, which was included in the 
Regulatory Evaluation, in its comment on the 
notice of proposed rulemaking. 

In response to the agency's request for 
clarification, Ford indicated that of the $11 
increase in costs that it projects, $8 is related 
to increased quality control by parts 
suppliers and $3 represents amortization of a 
$10 million initial investment. Of the $10 
million, $7.5 million was said to be for the 
purchase of nine chassis dynamometers and 
the upgrading of nine other dynamometers to 
be used to check brake performance at their 
nine truck plants. The remaining $2.5 million 
was attributed to engineering costs 
associated with compliance certification and 
quality control. 

In setting the requirements for the 
amendment, the agency specifically took into 
account production variability. All 
manufacturers balance their level of quality 
control with the margin of compliance that 
they believe is necessary to be confident of 
100 percent compliance. By designing braking 
systems for a level of performance which 
provides a sufficient margin of compliance to 
account ^or production variability, the 
substantial quality control costs cited by 



Ford should be made unnecessary. The 
agency took those factors into account when 
making its cost estimates and assumed that 
manufacturers would upgrade their vehicles' 
braking systems, where necessary, to 
provide a margin of compliance so as to make 
substantial quality control costs unnecessary. 
Further, the test requirements of Standard 
No. 105 do not specify the use of chassis 
dynamometers. While such devices may be 
useful for the purposes of quality control in 
, checking such vehicle components as braking 
systems, speedometers, and emissions 
systems, their use is neither necessary nor 
sufficient to assure compliance with Standard 
No. 105. 

On the issue of benefits, the Brake System 
Parts Manufacturers Council (BSPMC) cited 
in its petition a statement made in The 
Automobile Calendar by the United States 
Regulatory Council that NHTSA cannot 
predict the precise level of safety 
improvement resulting from the January 1981 
final rule because of the isolated effect of a 
number of interrelated accident factors, such 
as driver performance, vehicle responsiveness, 
and the variable characteristics of the 
highway and environment. That statement 
was cited by BSPMC as evidence that the 
agency does not know the benefits that the 
final rule will entail. 

Both the notice of proposed rulemaking 
and the preamble to the final rule explained 
that in carrying out the mandate of the 
National Traffic and Motor Vehicle Safety 
Act to issue vehicle safety standards to 
protect the public against unreasonable risk 
of vehicle accidents and of death and injury 
occurring as a result of such accidents, the 
agency is confronted with inherent problems 
that limit the degree of precision achievable 
in estimating the benefits of proposed 
standards. Engineering and accident 
analyses can clearly demonstrate that certain 
vehicle improvements will facilitate the 
performance of the driver's task and thereby 
improve safety. In this case, there is also a 
study showing that reducing stopping 
distances will reduce accidents. However, it 
is virtually impossible to isolate individual 
factors to arrive at precise and certain 



PART 571; S 105-83-PRE 77 



conclusions about the quantified benefits that 
will accrue. 

The notices explained that given the duty 
to act under this precautionary statute in the 
area of accident avoidance notwithstanding 
an inherent measure of imprecision and 
uncertainty, the agency has developed and 
issued accident avoidance standards while 
attempting within its capabilities to quantify 
the benefits of the standards and limit the 
uncertainty. Before issuing the proposal to 
amend Standard No. 105, the agency 
carefully evaluated and estimated the 
benefits that will accrue from the 
amendment. Those estimates were included 
in the Regulatory Evaluation prepared by the 
agency and made available to the public. 

Ford's petition challenged the statement in 
the Regulatory Evaluation that an average 4 
percent reduction in stopping distance 
capability will produce a 5 to 9 percent 
reduction in accidents where brakes are used. 
That statement, which was based on a study 
by the Institute for Research in Public Safety 
(IRPS), was used by the agency in projecting 
a reduction of 1,700 to 3,500 LTM-related 
accidents in the first year after the 
requirements became effective. The 
preamble to the final rule discussed the IRPS 
study at some length in response to a 
comment by Ford. 

Ford's petition did not discuss the agency's 
response to its comment regarding the IRPS 
study. Instead, Ford stated that it is 
"obvious" that a minor improvement (such as 

4 percent) in the maximum stopping distance 
capability of a vehicle can be utilized only in a 
very small proportion of accidents (well under 

5 percent). That commenter concluded that 
reductions in LTM accidents would be 
limited to only the 5 percent of accidents in 
which this maximum capability was utilized. 
According to Ford, that would make the 
projected benefits virtually disappear. 

Ford's petition gave no basis for its 
assertion that it is "obvious" that a 4 percent 
improvement in the maximum stopping 
distance capability of a vehicle can be utilized 
only in a very small proportion of accidents. 
Nor did Ford cite any source for its 5 percent 
figure. As noted above, the agency factored 



into its estimates of benefits the fact that 
brakes are used in about 50 percent of 
accidents. The 50 percent figure is derived 
from the IRPS study. 

Moreover, in addition to the projected 
reduction of 1,700 to 3,500 LTM-related 
accidents in the first year after the 
requirements become effective, the 
improvement in stopping distance capability 
will provide benefits in accident situations 
where brakes are used but the accident is not 
prevented. Those benefits will result from 
the fact that the vehicles will be traveling at 
a slower rate of speed when the accident 
occurs, thereby reducing the severity of the 
accident. For example, assuming a vehicle's 
maximum stopping distance capability is 
utilized from a speed of 60 mph, at the point 
where the improved vehicle is going less than 
2 mph, the unimproved vehicle would have 
been going about 13 mph. At the point where 
the improved vehicle is going 10 mph, the 
unimproved vehicle would have been going 
about 16 mph. In the absence of information 
contradicting the agency's estimates of 
benefits or the studies on which they are 
based, the agency continues to believe that its 
estimates of benefits are correct. 

NHTSA has considered the economic and 
other impacts of the January 1981 final rule 
and this amendment and has determined that 
they are not major within the meaning of 
Executive Order No. 12291. The agency has 
further determined that they are not 
significant within the meaning of the 
Department of Transportation regulatory 
procedures. Copies of the agency's 
Supplement to the Final Regulatory 
Evaluation may be obtained by writing 
NHTSA's Docket Section at the address 
given at the beginning of this notice. 

Although NHTSA has considered the 
effects of these amendments on small 
businesses, the agency has not prepared a 
regulatory flexibility analysis. Such an 
analysis is not necessary in this case, since 
the Regulatory Flexibility Act applies only to 
rules for which an NPRM was issued on or 
after January 1, 1981. The NPRM for the 
extension of Standard No. 105 to trucks, 



PART 571; S 105-83-PRE 78 



buses and MPV's was published in October Issued on December 15, 1981. 

1979. 

The agency has also analyzed these 

amendments for purposes of the National Raymond A. Peck, Jr. 

Environmental Policy Act and has Administrator 

determined that they will not have a 46 F.R. 61887 

significant effect on the human environment. December 21, 1981 



PART 571; S 105-83-PRE 79-80 



PREAMBLE TO AN AMENDMENT TO 
FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 105 

Hydraulic Brake Systems 
[Docket No. 70-27; Notice 28] 



ACTION: Final rule. 

SUMMARY: This notice amends Standard No. 105, 
Hydraulic Brake Systems, to provide an optional 
test procedure for trucks, buses other than school 
buses, and multipurpose passenger vehicles 
(MPV's) with a gross vehicle weight rating (GVWR) 
of greater than 10,000 pounds. The standard 
becomes applicable to these vehicles on September 
1, 1983. The amendment permits manufacturers 
to meet the partial failure requirements after con- 
ducting the standard's full test sequence preceding 
the partial failure test instead of the abbreviated 
test sequence generally specified for these vehicles. 
Under this option, manufacturers continue to be 
required to meet only the requirements of those 
tests in the abbreviated test sequence. 

EFFECTIVE DATE: September 1, 1983. 

SUPPLEMENTARY INFORMATION: Standard No. 
105, Hydraulic Brake Systems, provides that 
vehicles must meet a variety of performance re- 
quirements when tested according to a lengthy list 
of test procediu"es and in the sequence in which the 
procedures are listed by the standard. Currently, 
the standard is only applicable to passenger cars 
and school buses. However, effective September 1, 
1983, the standard becomes applicable, in whole 
or in part, to trucks, all types of buses, and 
multipurpose passenger vehicles. (Final rule 
published in the Federal Register (46 FR 55) on 
January 2, 1981; response to petitions for recon- 
sideration published December 21, 1981 (46 FR 
61887).) 

While Standard No. 105 was extended on a 
general basis (with some modifications) to vehicles 



with a gross vehicle weight rating (GVWR) of 
10,000 poimds or less, only limited requirements 
were made applicable to vehicles with a GVWR 
greater than 10,000 poimds. (The steindard's full 
requirements already applied to all school buses, 
including those with a GVWR greater than lO.CKX) 
pounds.) The abbreviated test sequence applicable 
to heavy vehicles other than school buses is similar 
to the full test sequence, except that many of the 
tests are eliminated. 

On July 14, 1983, in response to concerns raised 
by General Motors (GM) about an apparent 
anomaly in the test procedure, NHTSA published 
a notice of proposed rulemaking (NPRM) in the 
Federal Register (48 FR 32202) to provide an op- 
tional test procediu-e for heavy vehicles other than 
school buses. As explained in that notice, the 
agency was informed by GM that some of its heavy 
vehicles were having difficulties in meeting Stan- 
dard No. 105's partial failiu-e requirements under 
the limited test sequence. (The partial failure test 
ensiu-es that a vehicle's breikes are capable of 
bringing the vehicle to a controlled stop in a 
reasonable distance if a part of the service brake 
system should fail.) Under the full test sequence, 
the partial failure test is conducted well into the 
test sequence, following three effectiveness tests, 
burnish and rebumish (i.e., break-in or condition- 
ing) procedures, and the parking brake test. Of 
these various steps, only one, the bxumish pro- 
cedure, is included in the limited test sequence. 

GM informed NHTSA that it discovered, late in 
its compliance testing, that certain of its heavy 
vehicles, as designed, were imable to meet the pjir- 
tial failure requirements under the limited test se- 
quence. However, the same vehicles would meet 
the partial failure requirements if tested under the 



PART 571; S 105-83-PRE 81 



full test sequence. 

According to GM, redesign of some of its heavy 
vehicle braking systems would be required to meet 
the partial failure requirements under the limited 
test sequence. That company stated that in the 
short run the minimum cost resulting from such 
redesign would be in excess of $100 per vehicle, 
without improving user safety. Annual production 
of approximately 20,000 vehicles would be affected. 
Given the economic consequences of this apparent 
anomaly related to the test procedure, GM re- 
quested that the standard be {unended to correct it. 

After analyzing the issues raised by GM, NHTSA 
agreed that the standard should be amended. The 
NPRM explained that the elimination of the other 
procedures from the limited test sequence could 
have the effect of increasing the stringency of the 
later partial failiu-e test. The reason for this is that 
some brakes tend to become more effective as they 
are tested, because temperature conditioning im- 
proves the friction of the brake pads. 

The NPRM also explained that the increased 
stringency of the peutial failure test under the 
limited test sequence was neither intended nor 
foreseen by the agency. Indeed, the stopping 
distances for the partial failure test were beised on 
the assumption that the full test sequence would 
be conducted. The same stopping distances are ap- 
plicable to heavy school buses, but they are tested 
under the full test sequence. 

NHTSA proposed that manufacturers be given 
the option of subjecting their heavy vehicles to the 
full test sequence preceding the partial failure test 
instead of the limited test sequence. The NPRM ex- 
plained that manufacturers would not be required 
to meet performance requirements associated with 
the additional tests under this proposed option. 
However, manufacturers would be required to con- 
duct the additional tests in accordance with the 
standard's specified test procedures. 

Three comments were received by the agency, all 
of which supported adoption of the proposed amend- 
ment. GM commented that the NPRM properly 
described the situation as an unexpected and unin- 
tended increase in test stringency arising solely 
from the elimination of several test sequence steps 
in the interest of test efficiency and that the dif- 
ficulty is only one of procedure and not one that 
in any way affects motor vehicle seifety. That com- 
pany emphasized that the brake system in ques- 
tion is very similar to that on its school buses of 
equivalent GVWR and when tested to the full se- 



quence schedule, as is the school bus system, meets 

all applicable requirements. ( 

GM also stated that the proposed solution is the 
most logical approach to elimination of this unin- 
tended increase in stringency. That company noted 
that giving the manufacturer the option to choose 
whether its vehicles are tested to the full or ab- 
breviated test sequence enables systems which 
have been developed to meet the full school bus re- 
quirements to also comply when used on trucks, 
without additional complication, while also allow- 
ing a manufacturer which has developed a system 
to comply with the abbreviated test sequence to use 
that system without additional testing. 

Ford commented that it agrees with the agency's 
analysis that the elimination of certain procedures 
from the test sequence applicable to vehicles other 
than the subject heavy vehicles could have the ef- 
fect of increasing the stringency of the partial 
failure test in the abbreviated test sequence, and 
that it supports the proposed amendment. Chrysler 
submitted a comment which stated that it concurs 
with the proposed amendment. 

After reviewing the comments, NHTSA heis 
determined that the amendment should be adopted 
as proposed. An effective date of September 1, 1983, 
is provided. The agency has determined that an ef- A 
fective date of such short notice is in the public in- I 
terest given the imminence of the September 1, 
1983, effective date for Standard No. 105's applic- 
ability to these vehicles, and the optional nature 
of the amendment. 

The agency has considered the costs and other 
impacts of this amendment and has determined 
that it is not major within the meaning of Ex- 
ecutive Order 12291 or significant within the 
meaning of Department of Transportation's 
regulatory procedures. Further, the agency con- 
cludes that the economic and other consequences 
of the amendment are so minimal as not to require 
preparation of a full regulatory evaluation. Due to 
the optional nature of the amendment, no new costs 
are imposed on manufacturers or consumers. The 
amendment will result in some cost savings to 
manufacturers and consumers since it eliminates 
the need for redesign of some brake systems. In the 
short run, these savings could be relatively high 
on a per vehicle basis. As noted above, GM 
indicated that short-run redesign costs would have 
been in excess of $100 per vehicle, had the standard 
remained unchanged. In the longer run, however, 
NHTSA believes that these savings would probably 



PART 571; S 105-83-PRE 82 



be low, since, with a long leadtime, manufacturers 
could likely redesign their brakes at a much lower 
cost to comply with the requirements under the 
abbreviated test sequence. 

The agency has considered the effects of this pro- 
posal in relation to the Regulatory Flexibility Act. 
I certify that this amendment will not have a 
significant economic impact on a substantial 
number of small entities. Small businesses will be 
affected by the amendment only to the extent that 
they are sellers or pxirchasers of affected vehicles. 
Small organizations and small government 
jurisdictions will only be affected to the extent that 
they are purchasers of affected vehicles. The 
amendment will result in some lower vehicle 
prices, thereby benefitting both sellers and pur- 
chasers. However, such savings are sufficiently 
small relative to the purchase price of heavy 
vehicles, even in the short nm when they are ex- 
pected to be at their highest, that they are unlikely 
to significantly affect purchasing decisions. 

Finally, the agency has analyzed this amend- 
ment for §571.105 [Amended]. 



Section S7 is amended by revising the paren- 
thetical £ifter the first sentence of the paragraph 
to read as follows: 

(For vehicles only having to meet the re- 
qviirements of S5.1.2 and S5.1.3 in section S6.1, the 
applicable test procedures and sequence are S7.1, 

57.2, S7.4, S7.9, S7.10 and 87.18. However, at the 
option of the manufacturer, the following test pro- 
cedures and sequence may be conducted: S7.1, S7.2, 

57.3, S7.4, S7.5, S7.6, S7.7, S7.8, S7.9, S7.10 and 
S7.18. The choice of this option shall not be con- 
strued as adding to the requirements specified in 
S5.1.2 and S5.1.3.) 

Issued on August 30, 1983 



Diane K. Steed, 
Deputy Administrator 

48 F.R. 39939 
September 2, 1983 



PART 571; S 105-83-PRE 83-84 



^ 



Eff*cHv«: September 1, 1974 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 106 

Brake Hoses 
(Docket No. 1-5; Notice 8) 



This notice amends 49 CFR 571.106, Motor 
Vehicle Safety Standard 106, Hydraulic Brake 
Hoses, by (1) extending its requirements to all 
motor vehicles and hydraulic, air, and vacuum 
brake hose, brake hose assemblies, and brake 
hose end fittings for use in those vehicles, (2) 
replacing some design-oriented requirements with 
performance requirements for brake hose, brake 
hose assemblies, and brake hose end fittings, and 
(3) establishing comprehensive labeling require- 
ments for brake hose, brake hose assemblies, and 
brake hose end fittings. 

A notice of proposed rulemaking on this sub- 
ject was published on March 30, 1971 (36 F.R. 
5855). It revised and corrected earlier proposed 
amendments and propoccd the elimination of 
many design specifications in favor of broad 
performance requirements. This reorientation 
generated little comment, but extensive comments 
were received on the details of the proposed 
requirements. 

Tests conducted by the NHTSA Safety Sys- 
tems Laboratory and comments to the docket 
both indicated that the extensive sequential test- 
ing proposed in the NPRM could be an unpre- 
dictable measure of brake hose performance and 
much sequential testing was eliminated. One of 
the remaining sequential tests requires that all 
hose assemblies meet the constriction test as well 
as any other single test. 

Several comments indicated confusion con- 
cerning the rule's applicability to components of 
the brake system. The definition of brake hose 
now limits the standard to flexible conduits that 
transmit or contain the fluid pressure or vacuum 
used to apply force to a vehicle's brakes. This 
excludes such hose as that from the brake fluid 
reservoir to the master cylinder, and that from 



the air compressor discharge to its reservoir. 
Chassis plumbing which is flexible falls within 
the definition of brake hose, as does hose from 
the engine to the vacuum booster. 

In response to continued requests for physical 
tolerances and related accommodations for test- 
ing, it is reiterated that the safety standards 
should in all cases be considered as performance 
levels that each vehicle or item of equipment 
must meet, and not as instructions for manu- 
facturer testing. Thus, a 35-hour continuous 
flex test .procedure sets the minimum perform- 
ance level that the hose must meet when the 
NHTSA tests for compliance. The manufacturer 
may certify this performance level on the basis 
of interrupted tests as long as, in the exercise of 
due care, these tests provide assurance that his 
hose complies and will withstand 35 hours of 
continuous flexing. In response to another ques- 
tion, the manufacturer must determine for him- 
self how frequently he should test his products 
to ensure that they comply. 

The standard does not establish varying burst 
strength requirements for different size hose, 
because all sizes may be subject to extreme pres- 
sure conditions. Neither does the standard re- 
move wire-braided air brake hose from the 
adhesion requirements as requested, because the 
NHTSA has concluded that properly embedded 
wire-braided hose will sustain an 8-pound pull, 
and that no sufficient data exists to exempt wire- 
braided hose at this time. 

Labeling requirements have been modified in 
response to comments to permit (1) lettering to 
fit smaller size hoses, (2) antitorque stripes that 
are "clearly identifiable" in order to accommo- 
date a molding process as well as color-striping, 
(3) use of fractions to express the hose inside 



PART 571; S 106— PRE 1 



EffKllv*: SapMmbtr I, 1974 

diameter, and (4) interruption of the second 
stripe with optional additional information not 
permitted in the legend that interrupts the first 
stripe. In this way, the labeling provision re- 
quires certain safety-related information ex- 
pressed in a specified format, and it also permits 
labeling with additional information by the 
manufacturer at his option. For example, sev- 
eral comments suggested the use of "air-brake" 
in lieu of "A" and inclusion of SAE air brake- 
hose type designations as. a part of labeling air 
brake components. Another comment requested 
metric labeling. As modified, the standard now 
permits all this information to be placed on the 
hose as additional information. 

Labeling requirements for brake hose end fit- 
ting manufacturers no longer include the as- 
sembly completion date. Instead, the assembler 
is required to place a band on each hose assembly 
which indicates the assembly completion date. 
"Brake hose assembly" has been redefined to ex- 
clude assemblies containing used components, 
and this effectively excludes repair operations 
from the requirements of the standard. 

The amendment has been reorganized to 
clearly indicate that it applies to three types of 
hose, hose assemblies, and end fittings. The re- 
quirements and test procedures for each type of 
hose have been grouped together for clarity, in 
response to docket comments. 

Changes to the hydraulic brake hose require- 
ments include revision of many sequential tests. 
The 1,500 psi air pressure resistance test was 
eliminated as an inappropriate measure of hy- 
draulic brake hose performance. The water 
absorption test proposed in the NPRM was di- 
vided into three distinct tests. The test tem- 
perature in the brake fluid compatibility test 
has been lowered to more accurately reflect ve- 
hicle operating conditions and to approach a 
more suitable test temperature for the specified 
procedure. 

Few changes were made to the vacuum brake 
hose section. In response to the request of its 
manufacturers, %2-inch hose has been added to 
the performance requirements data. Distinctions 
between light and heavy duty hose were largely 
eliminated. 



All sequential testing except for the constric- 
tion test and one water absorption-tensile 
strength test has been eliminated from the air 
brake hose requirements. Comments indicated 
that the extensive combination of tests was in- 
appropriate to measure the adequacy of tradi- 
tionally constructed air brake hose. The 
ultraviolet test has been eliminated until suf- 
ficient data is generated to support a minimum 
performance requirement. The standard has 
also been modified to allow use of permanent as 
well as reusable end fittings. As anticipated in 
the NPRM, outside and inside diameter specifi- 
cations have been added to the requirements for 
two types of air brake hose, although these 
specifications do not require the use of Standard 
SAE 100R5 fittings as proposed in the NPRM. 

The suggested standardization on 100R5 fit- 
tings generated the greatest number of comments 
on the rulemaking. Comments generally agreed 
that thread engagement and component attach- 
ment should be standardized. However, dis- 
agreement exists on which fitting is most suitable 
for standardization. Many comments indicated 
that type E fittings are predominant in the in- 
dustry and will be more so in the future and that 
their non-proprietary design permits manufac- 
ture by anyone. The NHTSA has decided, on 
the basis of the comments received, not to stand- 
ardize on any type of fitting at this time. This 
amendment only establishes hose diameters and 
tolerances intended for use in reusable air brake 
hose assemblies as a first step toward standardi- 
zation of the air brake hose assembly. Notice 
and further opportimity to comment will pre- 
cede Any rulemaking on the standardization of 
air brake hose assemblies. 

In consideration of the foregoing, Standard 
No. 106, Brake Hoses, 49 CFR Part 671.106, is 
amended to read as set forth below. 

Effective date: September 1, 1974. 

(Sec. 103, 119, Pub. L. 89-563, 80 Stat. 718, 
15 U.S.C. 1392, 1407; delegation of authority at 
49 CFR 1.51.) 

Issued on November 5, 1973. 

James B. Gregory 
Administrator 

38 F.R. 31302 
November 13, 1973 



PART 571; S 106— PRE 2 



EfFeclive: January 29, 1974 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 106 

Brake Hoses 

(Docket No. 1-5; Notice 9) 



This notice amends Standard No. 106, Brake 
hoses, 49 CFR 571.106, to require a manufacturer 
designation in place of the manufacturer identifi- 
cation code assigned by the National Highway 
Traffic Safety Administration (NHTSA) which 
is presently required by the labeling provision. 

The NHTSA has not completed consideration 
of comments to its manufacturer's identification 
code proposal published June 7, 1973 (38 F.R. 
14968). General Motors has stated that produc- 
tion of 1975 model vehicles that conform to 
Standard 106 will require the immediate manu- 
facture of brake hose that conforms to Standard 
106. This amendment modifies the identification 
requirements to permit the use of manufacturer 
designations, such as those presently in use, until 
the NHTSA issues a final rule on the manufac- 
turer's identification code proposal. At that time 
the standard would be amended again to require 
whatever code might be assigned by the NHTSA. 

Other matters raised by petitions for recon- 
sideration are presently under consideration and 



will be answered in accordance with the proce- 
dures of 49 CFR 553.35, Petitions for recon- 
sideration. 

In consideration of the foregoing, Standard 106 
(49 CFR 571.106) is amended .... 

Effective date : January 29, 1974. Because this 
amendment creates no additional burden, and be- 
cause of the immediate need for an effective re- 
quirement applicable to equipment to be produced 
for the 1975 model year, it is found for good 
cause shown that notice and public procedure 
thereon are impracticable, and that an immediate 
effective date is in the public interest. 

(Sees. 103, 119, Pub. L. 89-563, 80 Stat. 718, 
15 U.S.C. 1392, 1407; delegation of authority at 
49 CFR 1.51.) 

Issued on January 23, 1974. 

James B. Gregory 
Administrator 

39 F.R. 3680 
January 29, 1974 



PART 571; S 106— PRE 3-4 



Effective: September 1, 1974 
January 1, 1975 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 106-74 

Brake Hoses 
(Docket No. 1-5; Notice 10) 



This notice responds to petitions for recon- 
sideration of amended Standard 106, Brake hoses, 
49 CFR 571.106, published November 13, 1973 
(38 F.R. 31302). In response to comments by 
36 manufacturers and users of brake hoses, the 
National Highway Traffic Safety Administration 
(NHTSA) amends the definitions, labeling, and 
performance provisions of the standard in several 
respects. 

The Motor Vehicle Manufacturers Association, 
the American Trucking Association, and three 
manufacturers questioned the applicability of the 
standard to nylon and thermoplastic tubing used 
in the chassis plumbing of air brake systems. 
They asserted that Notice 7 offered no opportunity 
for comment on the properties and use of this 
material and that no safety need could justify 
its inclusion in the standard. The comments 
point to a distinction in industry terminology be- 
tween "tubing" and "hose" to argue that NHTSA 
use of the term "hose" limited the proposal to 
traditional applications of six SAE hose types 
at articulating points in the air brake system. 

The NHTSA considers that the broad defini- 
tion of "Airbrake hose" provided an opportunity 
to comment on the issue of tubing. Notice 7 de- 
fined "Airbrake hose" as "a flexible hose for use 
in an airbrake system . . ." and it clarified this 
definition in the preamble to the notice. 

Major revisions have been made in the air- 
brake hose portion of the proposal by elim- 
inating the six types previously specified. 
Thus an airbrake hose under the proposal may 
be manufactured from any material as long as 
the hose can meet the performance require- 
ments of the standard. 

The NHTSA included "flexible" in its definition 
of hose, desjiite the common meaning of hose as 



flexible pipe or tubing, to emphasize the exclusion 
of relatively inflexible elements of an airbrake 
system such as copper tubing commonly found in 
chassis tubing. Finally, the broad term "air 
brake system" adequately gives notice of the 
standard's applicability to the chassis plumbing 
portion of that system. The NHTSA deter- 
mined that a safety need exists to include flexible 
chassis plumbing in this standard because it is 
used in the same environment as hose located at 
articulating points and is subject to many of the 
same types of stress, including heat, cold, and 
pressure. A failure of either flexible conduit 
creates as great a safety hazard. For these rea- 
sons, the petitions that tubing be excluded from 
the standard are denied. 

Manufacturers who commented on the use of 
nylon and thermoplastic in air brake systems ex- 
pressed confidence that their products, which are 
in widespread use as chassis plumbing, will meet 
the requirements of the standard. They re- 
quested testing to exclude inadequate materials 
which might also meet the present requirements. 
The NHTSA expects to propose additional re- 
quirements after review and testing demonstrate 
that traditional hose materials presently in use 
will not be excluded arbitrarily. In the interim, 
the NHTSA's safety defect authority can pre- 
vent the use of inadequate materials. 

To accommodate the inclusion of nylon and 
thermoplastic, the comments also requested a 
revision of the tensile strength value for the 
smaller nylon and thermoplastic hose. This 
change has been made. It should be stressed 
that the applicability of this standard to nylon 
and thermoplastic tubing does not affect tubing 
construction or characteristics. 



PART 571; S 106— PRE 5 



Effective: September 1, 1974 
January 1, 1975 



"Brake hose" is defined in the final rule as "a 
flexible conduit that transmits or contains the 
fluid pressure or vacuum used to apply force to 
a vehicle's brakes." Wagner Electric and several 
other manufacturers argued that a definition like 
this which differs from accepted industry term- 
inology should include a list of the parts of the 
brake system it covers. Actually, the use of 
general language different from industry term- 
inology is specifically intended to avoid identifica- 
tion with specific designs and thereby permit 
the definition to accommodate future designs as 
they develop. The preamble refers to specific 
lines only in response to manufacturer requests 
for interpretations, and the NHTSA will con- 
tinue to provide interpretations to interested 
persons upon request. The NHTSA interprets 
the term "flexible" to exclude copper or steel 
tubing. In response to Chrysler, General Motors, 
Ford, and Mercedes-Benz, the NHTSA reiterates 
that the vacuum and hydraulic booster lines that 
service power brake systems transmit or contain 
pressure used to apply force to a vehicle's brakes 
within the meaning of the definition. Accessory 
air lines such as those to the power air horn and 
windshield wipers are, of course, excluded. 

The definition of "brake hose assembly" in the 
rule covered both combinations of clamps and 
hose and combinations of end fittings and hose. 
The NHTSA has deleted reference to clamps, in 
agreement with manufacturers who pointed out 
that the mounting of a slip-on clamp and hose is 
an essentially different manufacturing operation 
that, if regulated, should be subject to different 
performance requirements from brake hose as- 
semblies. The clamp assemblies are subject to 
NHTSA safety defect authority. Comments dis- 
agreed for various reasons on the exclusion of 
hose assemblies containing used components from 
the standard. The NHTSA concludes that the 
exclusion is realistic and justified. 

The standard now defines "permanently at- 
tached end fittings" to make clear that 3-piece 
hose fittings which utilize sacrificial sleeves or 
ferrules are permanently attached end fittings 
and that the hose used with them is not pro- 
hibited by S7.1. In addition to the action taken 
with respect to the definition, %-in and V^-in 
hose sizes have been added to Table III under 



both Type I and Type II hose in order that their 
use may be continued. 

The definition of "rupture" lias been modified 
slightly to make clear that the two types of 
failure included in the definition are "separation 
of the hose from its end fitting" and "leakage". 
Both a small leak and a hose burst constitute 
"leakage" under this definition. 

Manufacturers of brake hose assemblies and 
vehicles petitioned for numerous variations in 
the labeling provisions. The many proposed 
changes in brake hose assembly labeling illustrate 
the importance of uniform labeling in a field 
where differing combinations of responsibility 
exist between manufacturers and installers of 
hose assembly components. 

The NHTSA has determined that the basic 
assembly banding technique set forth in Notice 
8 remains the clearest uniform identification 
method for assembly manufacturers. The band 
may be freely attached at any point on the as- 
sembly to minimize binding and wear as long as 
it is retained by the end fittings. An exception 
to the banding requirement has been made for the 
vehicle manufacturer who assembles and installs 
his own brake hose assemblies, because his assem- 
blies are integrally related to the vehicle, and the 
vehicle certification and identification informa- 
tion serves to identify and certify the hose as- 
sembly. The manufacturer may choose to band 
those hose assemblies subject to being rebuilt, to 
delimit his responsibiilty in the event a rebuilt 
assembly fails. 

Manufacturers will be permitted to mark the 
date of manufacture by day or month on the 
assembly and hose. Tlie identification code re- 
quired on each component is not yet available for 
issuance and therefore an amendment of the 
standard has already been issued to permit use 
of a manufacturer designation in place of the 
code (39 F.R. 3680, January 29, 1974). That 
language has been revised to allow the use of a 
manufacturer designation that does not consist of 
the block capital letters otherwise required by 
S5.2.2, S5.2.3, and S5.2.4. 

The labeling requirements now reflect the use 
of nominal inside and outside diameter desig- 
nations. Tlie hose labeling has been modified 
from "not less than 6 inches" to "not more than 



PART 571; S 106— PRE 6 



Effective: September 1, 1974 
January 1, 1975 



6 inches" in response to many requests, 'royotii's 
request for one-strii)e labelinji' of required and 
optional information has been denied, to ensure 
that the required information appears at least 
once on hose as short as 4 inclies. The NIITSA 
has denied requests for rearrann;ements of the 
required information, concluding that they would 
not make it clearer to the user. In response to 
Midland-Ross' request for clarification, it is re- 
iterated that, while the NHTSA requires certain 
safety-related information expressed in a certain 
format, it does not prohibit the addition of other 
information elsewhere on hydraulic, air, or 
vacuum hose. 

Several manufacturers of hydraulic brake hose 
assemblies argued that end-fitting labeling in- 
formation becomes meaningless once a fitting is 
permanently attached to a hose. They reasoned 
that the crimping process deforms the fitting, its 
coating, and i)ossibly the lettering, so that no 
fitting manufacturer would certify his product 
to the assembler, and that the responsibility for 
the fitting's conformity would in any case fall 
on the assembler. 

While the NHTSA expects the labeling in- 
formation to serve a useful purpose on reusable 
and 3-piece permanently attached end fittings, 
the limited benefit of markings on a crimped 
fitting justifies their elimination. In fact the 
one performance requirement that applies to fit- 
tings has been modified to reflect the crimping 
process and it effectively becomes the assembler's 
responsibility to meet this corrosion resistance 
provision. 

There were several general comments on the 
performance requirements and the test proce- 
dures. There were requests for physical toler- 
ances, especially for the expansion test apparatus, 
and related accommodations for test purposes. 
These arise from misunderstanding of the legal 
nature of the safety standards, which are per- 
formance levels that each vehicle or item of motor 
vehicle equipment must meet, and not instriictions 
for manufacturer testing. In the case of a cali- 
bration factor, for example, the NHTSA set an 
exact performance level by stating its require- 
ment without a tolerance. Then, in compliance 
testing, it determines the calibration factor of 
its equipment and gives the benefit of that factor 
to the manufacturer in assessing the test results. 



(correspondingly, the manufacturer should deal 
with an exact performance level by determining 
the calibration factor of his equipment and pe- 
nalizing his test results by that amount. Manu- 
facturer testing should be directed at pro\ ing the 
equipment's capability in tiie exercise of d)ie care, 
by testing mider conditions at least as adverse 
as any that could be established in accordance 
Avith the procedures. For example, to accept 
Goodyear's suggested room temperature range 
of 65° to 90°F. would permit tlie NIITSA to 
test at any temperature within the range, and a 
manufacturer would correspondingly have to test 
to assure himself that his product would conform 
at every point within the range. 

Toyota expressed some confusion about sequen- 
tial testing. As stated in S.").3, ST..*], and S9.2, a 
particular hose, end fitting, or hose assembly 
need not meet further requirements after having 
met the constriction requirements and any one 
other requirement listed. A particular hose as- 
sembly, therefore, would have to meet the con- 
striction requirement in each case and then one 
other selected requirement, of which 85.3.6, Water 
absorption and tensile strength^ is one example. 

The constriction requirement requires that any 
cross section which the NHTSA chooses to ex- 
amine will be a certain percentage of the nominal 
diameter. Again the manufacturer may utilize 
whatever test method convinces him in the exer- 
cise of due care that his i)roduct conforms to the 
constriction requirement. Chrysler objected to 
the application of the constriction test to hose 
assemblies, citing situations where restrictions 
are designed into brake systems for pressure con- 
trol. The NHTSA has determined that the estab- 
lished percentages limit constrictions to a safe 
level. 

With regard to the requirements as a group, 
it is noted that, while a hose must conform to 
any of the requirements, it need not be tested 
to requirements that are obviously inapplicable. 
For instance, thermoplastic tubing need not be 
subjected to the adhesion test because it is ob- 
vious that there are no layers in this constric- 
tion which could fail to adhere. 

Numerous comments were addressed to specific 
hydraulic performance requirements. The expan- 
sion and burst-strength requirements included a 



PART 571 ; S 106— PRE 7 



Effective: September 1, 1974 
January 1, 1975 



30-minute waiting period, wliich lias been elim- 
inated as unnecessary. The procedure is modified 
to better describe the test sequence, and two 
values in Table I are corrected. 

With regard to mounting hose assemblies hav- 
ing L-shnped end fittings in a flexing macliine. 
the te"' procedures iiave been modified to permit 
the use of adapters to secure the assembly to the 
machine with the same orientation as a straight 
assembly. 

The low-temperature resistance test for hy- 
draulic hose has been modified from — 05°F. 
to — 40°F. in line with air and vacuum hose test 
values. 

A hydraulic hose assembler objected that use 
of SAE RM-1 compatibility fluid had not been 
proposed in Notice 7 and therefore could not be 
specified in the final rule. Notice 7 proposed use 
of "brake fluid conforming to Standard No. 116." 
This means that the NHTSA could have cliosen 
any such fluid for use in its tests, and that the 
manufacturer would have to test with each fluid 
or otherwise assure himself in the exercise of 
due care that his hose assembly could meet the 
requirements using eacli fluid conforming to 
Standard No. 116. Specification of a single fluid 
is therefore a relaxation of the proposed require- 
ment. The Society of Automotive Engineers 
Referee Materials Subcommittee, which contracts 
for production of RM-1 fluid, has assured the 
NHTSA of its continued availability for at least 
the next 3 years. A modification of the require- 
ments has been made for mineral-type systems. 

The NHTSA agrees with AVagner Electric 
that the end fitting corrosion requirement must 
accommodate the crimping and labeling process, 
and the requirement is amended to permit dis- 
placement of the protective coating necessary to 
mark the fittings and attach it to a hose. 

Several comments were addressed to the air 
brake hose requirements. Clarifying language 
has been added to make clear that air brake hose 
assemblies may be constructed with permanent 
or reusable end fittings. Table III now includes 
A- and B-type hose in %- and V2-in special 
diameters to assure its continued availability, 
particularly for replacement purposes. The con- 
striction test value of 66 percent remains un- 
changed because the calculation method is 



already consistent with hydraulic value of 64 
percent. 

Table IV is revised to include outside dimen- 
sions. New, smaller radii for tubing tests can- 
not be adopted, however, until there has been 
notice and opiwrtunity to comment. In answer 
to Toyota's request for interpretation, it is cor- 
rect that the test cylinder radii are directly pro- 
portional to the diameter of the hose being tested. 
Suggestions to examine the inner as well as 
outer layers of hose subjected to the low-tem- 
perature resistance test will be considered in 
future rulemaking, since interested persons 
should be given notice and opportunity to com- 
ment. The same considerations apply to Samuel 
Moore Company's suggested liigher test tempera- 
ture in the oil -resistance requirement, more 
demanding percentages in the length change 
requirement and the high-temperature burst 
strength test. The oil resistance test specimen 
has been modified to one-third of an inch in 
width because i/^-in specimens can not be cut 
from the smaller hose sizes. Tlie burst strength 
value is reduced to 800 psi to accommodate nylon 
and thermoplastic tubing while retaining a safety 
performance level five times that of normal 
operating conditions. 

The application of air pressure has been re- 
tained in the length change test and the air 
pressure test, despite requests for "optional" pres- 
sure sources. Hidden options of this type are 
generally undesirable in the safety standards, 
since they make uncertain the level of required 
performance, and complicate the comparison of 
manufacturer and NHTSA test results. The 
manufacturer is free to use pressure sources other 
than air as long as his results assure him that 
the hose would meet the requirement if air were 
used. 

Manufacturers proposed alternative means of 
testing the adhesion of hose layers because of the 
difficulty associated with testing wire-braided 
and small diameter hose. As pointed out in the 
petitions, sufficient care in conducting the present 
test will prevent these difficulties. Any manu- 
facturer who believes that the alternative pro- 
cedure has significant advantages should submit 
a petition for rulemaking with supporting data. 



PART 571; S 106— PRE 



Some comments on the adhesion test argued 
for the averaging of test results witliout specify- 
ing any objection to the present procedure. At 
this time, it does not appear that averaging 
would be desirable for purposes of this standard. 
In another area, some tensile strength test values 
have been reduced in recognition of the use of 
tubing in nonarticulating applications. The dis- 
tinction between permanent and reusable fittings 
is eliminated, consistent with the rationale that 
the components may operate under the same con- 
ditions. 

The NHTSA denies Wagner Electric's re- 
quested re-establishment of the air pressure test 
procedures which appeared in Notice 7. These 
procedures were modified because comments ob- 
jected to the measuring technique. As noted 
previously, the manufacturer may use any test 
method which assures him the equipment meets 
the requirement as stated. 

One significant question was raised with regard 
to the vacuum hose requirements. Table V in- 
advertently listed the- same hose lengths and 
cylinder radii for the low and high temperature 
resistance tests. A new column of values is 
added to that table. 

Because of the additional leadtime required 
to purchase conforming brake hose and assemblies 
for use in vehicles which must conform to the 
standard, the effective date of the standard as it 
applies to vehicles is delayed 4 months to Jan- 



Effeclive: September 1, 1974 
January 1, 1975 

uary 1, 1975. An amendment to the presently 
effective Standard lOfi permits compliiince either 
with that standard or witii this standard, as it 
is effective September 1, 1974. 

Interested persons are reminded that, in addi- 
tion to the amendments set fortii lielow, an amend- 
ment of Standard 106 has already been issued 
which permits the use of a manufacturer desig- 
nation in place of the identification code called 
for in the rule as first issued. (39 F.R. 3680, 
January 29, 1974.) 

In consideration of the foregoing, both Stand- 
ard No. 106, 49 CFR 571.106, in its presently 
effective form and Standard No. 106 as it is effec- 
tive September 1, 1974, and January 1, 1975, are 
amended. 

The present Standard No. 106 is amended by 
the addition of a new paragraph .... 

Elective dates: September 1, 1974, for equip- 
ment covered by the standard; January 1, 1975, 
for vehicles to which the standard applies. 

(Sees. 103, 119, Pub. L. 89-563, 80 Stat. 718, 
15 U.S.C. 1392, 1407; delegation of authority at 
49 CFR 1.51.) 

Issued on February 20, 1974. 

James B. Gregory 
Administrator 

39 F.R. 7425 
February 26, 1974 



PART 571; S 106— PRE 9-10 



Effective: September 1, 1974 
March 1, 1975 
September 1, 1975 



PREAMBLE TO AMENDMENT TO MOTOR VEHICLE SAFETY STANDARD NO. 106-74 

Brake Hoses 

(Docket No. 1-5; Notice 11) 



This notice amends Standard No. 106, Brake 
hoses, 49 CFR 571.106, by modifying the defini- 
tion of "permanently attached end fitting", the 
effective date for brake hose assemblies and ve- 
hicles, several labeling requirements, and certain 
tensile strength, constriction, and corrosion re- 
sistance requirements, in response to petitions for 
reconsideration of amendments published Jan- 
uary 29, 1974 (39 FR. 3680) (Notice 9) and 
February 26, 1974 (39 FR 7425) (Notice 10). 
In addition, Toyo Kogyo Company, in a letter 
request for interpretation, pointed out an in- 
advertent change of language in Notice 8 (38 FR 
31302, November 13, 1973) which is corrected in 
this notice. 

Notice 9 

Notice 9 amended the standard to permit the 
use of "a designation that identifies the manufac- 
turer" of an end fitting, hose or hose assembly 
in place of a manufacturer identification code 
which the NHTSA is not yet prepared to issue. 
Any designation which is filed with the NHTSA 
may be used until the permanent code is imple- 
mented. The only comment on Notice 9 was 
made by Weatherhead Company, which objected 
to any interim marking on grounds of expense 
and advocated elimination of all label identifica- 
tion from' the hose. The NHTSA considers iden- 
tification other than a colored thread to be 
reasonable and necessary for rapid recognition, 
and Weatherhead's first petition is denied. 

Although not raised by Weatherhead in its 
petition, several assemblers have objected that the 
manufacturer designation requirement conflicts 
with the general industry practice of marking 
hose with the distributor's designation. The 
NHTSA requirement that the manufacturer des- 
ignation appear on one side of the hose in the 



required format does not in any way prevent 
labeling of hose with the distributor's designa- 
tion on the opposite side of the hose along with 
other optional information. 

Weatherhead petitioned for revision of the 
identification requirements to permit designations 
other than block capital letters and numerals. 
The necessary language has already been added 
to the standard in Notice 10. 

Weatherhead also requested a modification of 
the definition of "end fitting" that would exclude 
end fitting components from the labeling require- 
ments in order to accommodate the practice of 
assembler intermixing of components made by 
different manufacturers. Such an exclusion of 
components, combined with the present exclusion 
of labeling crimped-on fittings, would eliminate 
all identification requirements for all fittings. 
While unlabeled crimped fittings may be traced 
through the hose assembler's band, "renewable" 
or reuseable fittings must be labeled at least once 
to permit location of any defective fitting whi