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

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Federal Motor Vehicle Safety 
Standards and Regulations 

^,!ra°n?p?S Supplemepit 51— Amendments 

jfX'sST" and Interpretations Issued 

Administration -i-i i j r\r\r\ 

Through 1992 i^mmBmnitr 

TD8.6/2:992/SUPP.51 ^ i Sn^lfe^ 

Page Control Chart 

Federal Hotor Uefcicle Safetg Standa... ^ DEC f 7 ^93 

(1) Federal Motor Vehicle Safety Standard No. 105 , ' V^UUutJUMHv 

(a) Insen attached pages numbered PART 571; S 105— PRE 113 through PRE 123 behind page m't)t5Wminilwitqi)|t)ir 
PART 571; S105-PRE 111-112. 

(b) Substitute attached Standard 105 for Standard 105 in book. 

(2) Federal Motor Vehicle Safety Standard No. 108 

(a) Insert attached pages numbered PART 571; S108-PRE 391 through PRE 404 behind page in book numbered 
PART 571; S108-PRE 389. 

(b) Substitute attached Standard 108 (except for Art Pages) for Standard 108 in book. 

(3) Federal Motor Vehicle Safety Standard No. 1 1 1 

• (a) Insert attached pages numbered PART 571; Slll-PRE 29 through PRE 57 behind page in book numbered 

PART572;S111-PRE28. 
(b) Substitute attached Standard 111 for Standard 1 1 1 in book. 

(4) Federal Motor Vehicle Safety Standard 121 

(a) Insert attached pages numbered PART 571; S121-PRE 223 through PRE 239 behind page in book numbered 
PART 571; S121-PRE 222. 

(b) Substitute attached Standard 121 for Standard 1 2 1 in book. 

(5) Federal Motor Vehicle Safety Standard No. 131 

(a) Insert attached pages numbered PART 571; S131-PRE 13 through PRE 16 behind page in book numbered 
PART 571; S131-PRE 12. 

(b) Substitute attached Standard 131 for Standard 131 in book. 

(6) Federal Motor Vehicle Safety Standard No. 213 

(a) Insert attached pages numbered PART 571; S213-PRE 73 through PRE 91 behind page in book numbered 
PART 571; S213-PRE 71-72. 

(b) Substitute attached Standard 213 for Standard 213 in book. 

(7) Federal Motor Vehicle Safety Standard No. 214 

(a) Insert attached pages numbered PART 571; S214-PRE 75 through PRE 87 behind page in book numbered 
PART571;S214-PRE74. 

(b) Substitute attached Standard 214 for Standard 214 in book. 

(Continued on reverse) 

^P The Federal Motor Vehicle Safety Standards and amendments published In this format are for reference purposes 

only. They should not be considered as legally binding or be used as a source of authority In matters of litigation. 
The United States Code of Federal Regulations is the only source of legal authority for the standards. 



(8) Federal Motor Vehicle Safety Standard No. 217 

(a) Insert attached pages numbered PART 571: S217-PRE 23 through PRE 47 behind page in book numbered 
PART571;S217-PRE22. 

(b) Substitute attached Standard 217 for Standard 217 in book. 

(9) Part 572 — Anthropomorphic Test Dummies 

(a) Insert attached page numbered PART 572-PRE 103 behind page in book numbered PART 572-PRE 102. 

(b) Substitute attached PART 572 for PART 572 in book. 

(10) PART 586— Side Impact Protection 

(a) Insert attached pages numbered PART 586-PRE 5 through PRE 15 behind page in book numbered PART 
586-PRE 4. 

(b) Substitute attached PART 586 for PART 586 in book. 

(11) PART 588— Child Restraint Systems Recordkeeping 

Insert attached pages numbered PART 588-PRE 1 through PART 588-1 behind page in book numbered PART 

587-2. 

(12) PART 591 — Importation of Vehicles and Equipment Subject to Federal Safety Bumper and Theft 

Protection Standards 

(a) Insert attached page numbered PART 591 -PRE 51 behind page in book numbered PART 591 -PRE 50. 

(b) Substitute attached PART 591 for PART 591 in book. 



i 



PREAMBLE TO AN AMENDMENT TO FEDERAL MOTOR 

VEHICLE SAFETY STANDARD NO. 105 

Hydraulic Brake Systems 

(Docket No. 91-21; Notice 2) 
RIN: 2127 -AD34 



ACTION: Final rule. 

SUMMARY: This rule amends Federal Motor 
Vehicle Safety Standard No. 121, Air Brake Sys- 
tems, to require automatic brake adjusters on all 
air-braked vehicles and adjustment indicators on 
air-braked vehicles with external adjustment 
mechanisms. This rule also amends Standard No. 
105, Hydraulic Brake Systems, to require auto- 
matic brake adjusters on vehicles with hydraulic 
brake systems. However, the rule does not require 
adjustment indicators on hydraulically-braked 
vehicles because there do not appear to be signifi- 
cant problems with monitoring automatic brake 
adjusters on such vehicles. These amendments 
should improve the braking performance of 
vehicles by ensuring that their brakes are properly 
adjusted. 

DATES: Effective Dates: The amendments to 
Standard No. 105 become effective October 20, 
1993. 

The amendments to Standard No. 121 become 
effective October 20, 1994. 

SUPPLEMENTARY INFORMATION: 

Background 

General Information 
Proper brake adjustment is critical for maintain- 
ing safe stopping performance. Devices known as 
automatic brake adjusters automatically maintain 
proper brake adjustment, thus eliminating the 
need for frequent inspection and manual adjust- 
ment of the brakes. Automatic brake adjusters 
have been used on passenger cars and light trucks 
since the early 1960s and have been standard 
equipment on all such vehicles sold in recent 
years in the United States. In addition, the vast 
majority of medium and heavy duty vehicles with 
hydraulic brake systems have automatic brake 



adjusters. Automatic brake adjusters were intro- 
duced for use on heavy duty air-braked vehicles 
in the early 1960s and are widely used today. The 
installation rates of automatic brake adjusters by 
manufacturers of heavy duty air-braked vehicles 
range from 30 to 100 percent of their fleets. 

Safety Need and Practicability of Automatic 
Adjustment Devices 

Notwithstanding the importance of proper brake 
adjustment for maintaining safe stopping perform- 
ance, numerous studies have shown that brake 
adjustment is not being maintained on some air- 
braked medium and heavy duty vehicles that are 
not equipped with automatic brake adjusters. (See 
Automatic Slack Adjusters for Heavy Vehicle Air 
Brake Systems, DOT HS 807 724, February 
1991.) When brakes are under-adjusted, stopping 
ability is reduced and the probability of a crash 
is increased. When brakes are over-adjusted, 
maintenance costs and the possibility of a crash 
are increased as a result of excessive lining wear, 
wheel lock, or brake drum cracking. Such 
improper brake adiustment contributes to a 
significant number of crashes, including those in 
which vehicles are unable to stop in time and 
those in which there are "runaways" on steep 
mountain grades. 

As detailed in the notice of proposed rule- 
making (NPRM) for this rulemaking (56 FR 
20396, May 3, 1991), several studies highlight the 
problems associated with improper brake adjust- 
ment, especially on air-braked vehicles. These 
studies include the Office of Technology Assess- 
ment's (OTA's) September 1988 report Gearing 
Up for Safety, NHTSA's March 1987 Heavy 
Truck Safety Study Report to Congress, the 
National Transportation Safety Board's investiga- 
tions of heavy truck crashes, and a Federal High- 
way Administration study. 



PART 571; S105— PRE-113 



Based on the above-mentioned concerns, the 
National Transportation Safety Board rec- 
ommended that NHTSA develop a Federal Motor 
Vehicle Safety Standard requiring all newly 
manufactured commercial vehicles to have equip- 
ment ensuring that brakes are always properly 
adjusted. 

Automatic brake adjusters are now used on 
approximately 60 percent of new medium and 
heavy duty vehicles with air brakes. However, 
one major, and a number of smaller vehicle 
manufacturers, do not provide automatic brake 
adjusters as standard equipment, and many pur- 
chasers do not order them as optional equipment. 

NHTSA believes that automatic brake adjuster 
use has stabilized at about the current 60 percent 
level. NHTSA has conducted a large-scale fleet 
evaluation to assess the performance and reliabil- 
ity of automatic brake adjusters, as compared to 
manual adjusters on heavy commercial vehicles 
with S-cam air brakes. NHTSA collected brake 
adjustment data from several hundred fleet 
vehicles equipped with automatic and manual 
brake adjusters for approximately five years. The 
conclusions regarding the fleet examination are 
detailed in the NPRM. Among the principal 
conclusions were that: 

• Automatic brake adjusters generally maintained 
brake adjustments within the limits specified by 
the vehicle manufacturer. The medium percent- 
age of out-of-adjustment brakes for the fleet 
applications was about four percent. This rep- 
resents a far lower out-of-adjustment rate than 
is commonly found in roadside check studies of 
brake adjustment for manually-adjusted air 
brakes. 

• In the most successful applications, automatic 
brake adjusters consistently exhibited out-of- 
adjustment percentages of less than one per- 
cent. Thus, automatic brake adjusters dem- 
onstrated the potential for very effective 
performance levels. 

• The incidence of brake over-adjustment with 
automatically-adjusted brakes was low. In the 
fleet test, there was no case of an automatic 
brake adjuster over adjusting a brake enough to 
cause brake over-heating, wheel lockup, or 
excessive brake lining wear. 



Automatic Adjusters and Indicators 
on Air Brake Systems 

There are three principal types of air-braked 
systems used in this country: 1) S-cam actuators, 
2) wedge type actuators, and 3) disc brakes. For 
S-cam brakes, which comprise about 95 percent 
of air-brake systems, two major types of auto- 
matic brake adjusters are available. One adjusts 
on the basis of actual shoe-to-drum clearance. The 
other adjusts on the basis of the air chamber push 
rod stroke. All wedge type brakes, which com- 
prise about three percent of the market, have an 
internal automatic adjustment mechanism. As for 
disc brakes which comprise about two percent of 
air-brake systems, some have external self-adjust- 
ing mechanisms, while others have internal 
adjustment features. The external adjustment 
mechanism of an air disc brake system operates 
similarly to those on S-cam brakes. 

Brake adjustment indicators improve brake 
adjustment by increasing the convenience of 
checking brake adjusters and their proper func- 
tioning. Without brake adjustment indicators, 
measuring brake adjustment requires following a 
laborious and time-consuming manual procedure 
in which the push rod length must be measured 
before and during brake application. The proce- 
dure is especially difficult for brake chambers 
located at positions under the vehicle that are dif- 
ficult to reach. Also, a person checking brake 
adjustment must know the specific adjustment 
data for each chamber because some manufactur- 
ers have slightly different stroke lengths for the 
same size chamber. The procedure is also com- 
plicated because the chamber's make and model 
may be difficult to identify when it is covered 
with road dirt and corrosion. 

Several types of brake adjustment indicators are 
cuiTently available. One type involves air brake 
chambers with paint markings on push rods that 
indicate the level of adjustment. However, such 
markings may not be useful in certain applica- 
tions (e.g., with wedge brakes when the push rod 
is enclosed in a sleeve and with S-cam brakes 
having push rods with protective rubber boots). A 
second type of brake adjustment indicator is 
installed by inserting a guide arm and sliding 
stem assembly into a small hole in the air booster 
can. A third method involves attaching a hose 
clamp to the air chamber push rod to mark the 



PART 5/1: S105— PRE-114 



fully adjusted brake position relative to the air 
chamber housing. To check the brake adjustment, 
the space between the air chamber housing and 
hose clamp is compared with a bar gauge. 

Notice of Proposed Rulemaking 

On May 3. 1991, NHTSA published an NPRM 
in which the agency proposed to amend Standard 
No. 121 to require automatic brake adjusters and 
adjustment indicators on vehicles with air brake 
systems. (56 FR 20396) The NPRM also pro- 
posed to amend Standard No. 105 to require auto- 
matic brake adjusters on vehicles with hydraulic 
brake systems. NHTSA decided not to propose 
requiring adjustment indicators on hydraulically- 
braked vehicles because the agency believed that 
there were no significant problems with automatic 
brake adjusters for these vehicles or with check- 
ing the adjustment of such systems. 

Among the issues discussed in the NPRM were 
(1) the need to require automatic brake adjusters 
in passenger cars and other hydraulically braked 
vehicles, (2) specific provisions in the proposed 
language to require automatic brake adjusters on 
passenger cars, (3) the need for automatic brake 
adjusters on air-braked vehicles to correct for 
both under and over-adjustment, (4) the apparent 
absence of a need for automatic adjustment 
indicators for hydraulically braked vehicles, (5) 
visibility requirements for adjustment indicators 
on air-braked vehicles, (6) the necessary leadtime 
for the proposal, and (7) the costs associated with 
the rulemaking. 

Comments to the NPRM and the 
Agency's Response 

NHTSA received about 35 comments in 
response to the NPRM. These were from vehicle 
manufacturers, brake manufacturers, manufactur- 
ers of brake adjusters and adjustment indicators, 
heavy vehicle users, trade associations, and oth- 
ers. The majority of commenters generally agreed 
with the proposal to require brake adjusters on 
both hydraulic and air-braked vehicles and to 
require adjustment indicators on air-braked 
vehicles. In addition, commenters addressed spe- 
cific matters in the proposed regulation, including 
the issues of over-adjustment, visibility require- 
ments, and other provisions in the proposed regu- 
latory text. 

The agency has considered the points raised by 
the commenters in developing the final rule. The 



agency's discussion of the more significant com- 
ments and other relevant information is set forth 
below. The notice first addresses issues about 
automatic adjusters and indicators on vehicles 
equipped with air brakes because the safety prob- 
lem primarily involves, and consequently the 
agency's rulemaking efforts focus on, these 
vehicles. The notice then discusses adjustment 
devices on hydraulically-braked vehicles. 

Air-Braked Vehicles 

1. General Considerations 

As explained above, the safety problem with 
out-of-adjustment brakes primarily involves air- 
braked vehicles. Accordingly, the agency's rule- 
making efforts have focused on requiring auto- 
matic adjusters and adjustment indicators on such 
vehicles. 

In response to the NPRM's proposal to require 
automatic adjusters on air-braked vehicles, all but 
one commenter addressing this issue supported 
requiring automatic adjusters on air-braked 
vehicles. Those supporting the rulemaking 
included the American Trucking Associations 
(ATA). Truck Trailer Manufacturers Association 
(TTMA), General Motors (GM), Ford, and Advo- 
cates for Highway and Auto Safety (AHAS). 
AHAS stated that the amendments would mitigate 
the extent and severity of fatal and injury produc- 
ing accidents. Only one commenter, Mr. Robert 
Crail, a brake consultant, disputed the need for 
and effectiveness of automatic adjusters on air- 
braked vehicles. Mr. Crail stated that automatic 
adjusters are not accurate enough to be mandated, 
citing raw data about automatic slack adjusters. 

Based on the comments and other available 
information, NHTSA has determined that requir- 
ing automatic adjusters on air-braked vehicles will 
improve the brake performance of these vehicles. 
As the NPRM explained, out-of-adjustment brakes 
pose a significant safety problem that could be 
alleviated by requiring automatic brake adjusters. 
The agency notes that Mr. Crail's critical com- 
ments were based, in part, on raw data gathered 
from unscreened sources and uncontrolled test 
conditions. Therefore, his conclusions based on 
the data are questionable. While NHTSA 
acknowledges that older brake adjuster designs 
may not perform as well as properly maintained 
manual adjusters, the new generation of currently 
produced automatic adjusters provide superior 
brake adjustment. In addition, even the previous 



PART 571; S105— PRE-115 



generation of automatic brake adjusters are often 
superior to manual adjusters because some owners 
of vehicles with manual adjusters do not take the 
time to properly adjust or otherwise properly 
maintain their brakes. 

2. Proposed Regulatory Text 
The NPRM proposed amending Standard No. 
121 to require all vehicles with air brakes to be 
equipped with automatic adjusters. Specifically, 
the NPRM proposed that the standard be amended 
to require these devices on trucks, buses, and 
trailers, as follows: 

Each vehicle shall be equipped with a service 
brake system acting on all wheels. Wear of the 
service brakes shall be compensated for by 
means of a system of automatic adjustment, 
which maintains brake adjustment within the 
manufacturer's recommended adjustment limits. 
The condition of service brake adjustment shall 
be provided by a brake adjustment indicator 
that is discernible when viewed with 20/40 
vision, using an ordinary flashlight with two D- 
cell batteries from a position 8 feet away on 
the adjacent pavement surface. The brake 
adjustment indicator shall be capable of 
displaying the service brake adjustment condi- 
tions of: under-adjustment, over-adjustment, 
and fully adjusted within the manufacturer's 
specified limits. 

Commenters addressed various aspects of the 
proposed regulatory text, including specifying that 
brake adjustment be maintained within the manu- 
facturer's recommended adjustment limits, having 
adjusters correct for under and over adjustment, 
having indicators display the conditions of under, 
over, and full adjustment, and having visibility 
requirements. Along with the comments address- 
ing each of these considerations, the agency's 
response to the comments is presented below. 

a. Brake Adjustment within Manufacturer' s 
Recommended Adjustment Limits 

As explained above, the NPRM proposed that 
brake adjustment would have to be maintained 
"within the manufacturer's recommended adjust- 
ment limits." The agency had tentatively believed 
that requiring adjustment within the manufactur- 
er's recommended adjustment limits would pro- 
vide a more specific performance requirement. 

Several commenters, including White GMC/ 
Volvo, GM, Ford, Midland-Grau, and a brake 
indicator manufacturer, criticized the proposal to 



require maintaining brake adjustment within the 
manufacturer's recommended adjustment limits. ^^ 
These commenters believed that the proposal was ^H 
unnecessary, ambiguous, and would unreasonably 
burden manufacturers. GM and Ford stated that 
the proposal was potentially ambiguous since 
determining what "maintaining brake adjust- 
ment" means could be interpreted several ways. 
Accordingly, these commenters believed that 
some compliance test would be necessary if the 
agency adopted this provision. White GMC/ 
Volvo, GM, and Ford believed that the proposal 
might be interpreted as requiring the manufacturer 
to be responsible for brake adjustment throughout 
the vehicle's life, even though the manufacturer is 
typically responsible for compliance only until the 
first consumer purchase. In addition, some com- 
menters were concerned that the proposal did not 
specify an objective measure about the proper 
level of adjustment. This consideration led Mid- 
land-Grau to recommend that the standard incor- 
porate the Federal Highway Administration's 
requirements in appendix G to subchapter B of 
Chapter III, Title 49, Code of Federal Regula- 
tions. FHWA, based on input from the Commer- 
cial Vehicle Safety Alliance and brake chambers ^M 
manufacturers, has established a set of brake ^B 
adjustment tables that are published in the North 
American Uniform Vehicle Out-of-Service Cri- 
teria. The States rely on these roadside inspection 
tables to place a vehicle out of service if the 
adjustment limits are exceeded. 

After reviewing the comments and the available 
infomiation, NHTSA has determined that the final 
rule should not include a reference to maintaining 
adjustment within the manufacturer's rec- 
ommended limits. The agency agrees with com- 
menters that such a provision would not provide 
any significant safety benefits but might cause 
unnecessary complications and confusion. In 
terms of safety benefits, the final rule addresses 
the most important issue by requiring each 
vehicle to be equipped with a service brake sys- 
tem including means for automatic adjustment to 
compensate for wear of the system. The reference 
to the manufacturer's adjustment limits would 
have been superfluous and potentially confusing. 
Nevertheless, as explained below, the agency has 
decided to reference the FHWA's regulations ^ 

about "Vehicle Out-of-Service Criteria." By not fl 
including reference to maintaining adjustment 
based on the manufacturer's recommendations. 



PART 3/1; SI 05— PRE- 11 6 



this amendment is consistent with the proposed 
requirement about brake adjustment in Standard 
No. 135, Passenger Car Braise Systems. (56 FR 
30528, July 3, 1991). Accordingly, the final rule 
specifies that "Wear of the service brakes shall 
be compensated for by means of a system of 
automatic adjustment," without reference to a 
manufacturer's adjustment limits. The agency 
notes that there is no objective criteria as to what 
constitutes "maintains adjustment." In addition, 
as a general rule, the agency does not establish 
extended durability testing. The agency believes 
that to require that the adjustment be maintained 
throughout the lifetime of the vehicle is unrealis- 
tic, dependent upon the vehicle's exposure, and 
beyond the scope of NHTSA's authority. 

As for Midland-Grau's recommendation to use 
FHWA's regulations for "Driver Out-of-Service 
Criteria" for brake adjustment, NHTSA has 
decided to reference these provisions in Standard 
No. 121 because they are relevant to in-use heavy 
truck operation regulated by FHWA. Because 
amendments to Standard No. 121 require the use 
of brake adjustment indicators which require the 
display of underadjustment, a reference to adjust- 
ment limits is necessary. Those limits are speci- 
fied in Appendix G to Subchapter B of Chapter 
III, 49 CFR Parts 200 to 399. 

b. Brake Over-adjustment and Under-adjiist- 
ment 

The NPRM tentatively concluded that auto- 
matic brake adjusters should have the capability 
of correcting for both under and over-adjustment. 
The NPRM also proposed that a brake adjustment 
indicator be capable of displaying the brake 
adjustment conditions of under-adjustment, over- 
adjustment, and fully adjusted. The notice 
requested comments about whether these require- 
ments were feasible and whether they should be 
specified in the regulatory text. 

Twelve commenters, primarily heavy brake and 
vehicle manufacturers, opposed requiring brake 
adjusters to correct for over-adjustment. These 
commenters also opposed requiring the brake 
adjustment indicators to identify the over-adjusted 
and fully adjusted conditions. User groups, such 
as the Owner-Operator Independent Drivers 
Association supported these proposals. Navistar, 
Haldex, Bendix, Midland-Grau, Rockwell, Ford, 
the MVMA, Chrysler, Eaton, and the ATA 
believed that requiring the device to control for 
over-adjustment and having the adjustment indica- 



tor identify this condition were unnecessary and 
impracticable. MVMA stated that the incidence of 
over-adjustment is very infrequent and poses a 
minimal risk to safety. In addition, several manu- 
facturers explained that the condition of over- 
adjustment can be ascertained by excessive wear, 
abuse of the equipment, and in extreme cases, 
smoke. The commenters also stated that the pro- 
posal was impracticable because there was no 
current technology that reliably indicates the over- 
adjusted condition. After reviewing the comments 
and available infomiation, NHTSA concludes that 
requiring brake adjusters to correct for over- 
adjustment and having adjustment indicators show 
the over-adjusted and fully-adjusted conditions are 
unnecessary for safety and would be impractica- 
ble. In terms of the safety need, the fleet evalua- 
tion cited in the NPRM concluded that the 
incidence of brake over-adjustment was extremely 
low. NHTSA further notes that potential problems 
associated with over-adjustment will not be 
significant. The driver typically will be aware of 
over-adjustment because the brake system will 
drag and may begin to smoke. In terms of prac- 
ticability, the NPRM's tentative determination 
about the availability of automatic brake adjusters 
to correct for over-adjustment appears to be 
inconsistent with the current state of brake tech- 
nology. The agency now agrees with the com- 
ments that regulating over-adjustment would be 
impracticable given that such devices are not 
readily available. Based on the above, the final 
rule does not require brake adjusters to correct for 
over-adjustment and does not require the adjust- 
ment indicators to show the over-adjusted and 
fully-adjusted conditions. 

As for the condition of under-adjustment, most 
commenters, including Rockwell, MVMA, Ford, 
and GM believed that the agency should intro- 
duce requirements to prevent this brake condition. 
MVMA stated that the primary motivation and 
safety benefit underlying automatic brake adjust- 
ers is to minimize the incidence of under-adjust- 
ment. 

After reviewing the comments and the available 
information, NHTSA has decided to adopt provi- 
sions requiring brake adjusters to correct for the 
condition of service brake under-adjustment and 
have a device that indicates the under-adjusted 
condition. The agency agrees with the com- 
menters that under adjustment poses a significant 
risk to safety. In addition, NHTSA believes that 



PART 571; SI 05— PRE- 



this requirement is practicable since there cur- 
rently are several devices that are capable of 
indicating the under-adjusted condition. Accord- 
ingly, Sections 5.1.8 and S5.2.2 are amended to 
read, in relevant part, '"(b) Brake indicator. .. the 
condition of service brake under-adjustment shall 
be provided by a brake adjustment indicator ... 

c. Visibility' Requirements for Brake Adjust- 
ers 

The NPRM proposed that the brake adjustment 
indicator be discernible when viewed with 20/40 
vision, using an ordinary flashlight with two D- 
cell batteries from a position at least eight feet 
away on the adjacent pavement surface. The 
agency believed that these visibility requirements 
would allow a person to check brake adjustment 
without having to crawl under the vehicle. 

Commenters offered various views about the 
proposed visibility requirements. Manufacturers of 
aftermarket add-on indicators favored the pro- 
posal, while vehicle manufacturers and custom 
builders objected. Users of brake equipment 
offered mixed views. 

Several commenters, including Mack, Navistar, 
GM, the National Truck Equipment Association 
(NTEA), Haldex, the Truck Trailer Manufacturers 
Association (TTMA), and Flxible stated that the 
proposed visibility requirements were impractica- 
ble, especially for those vehicle configurations in 
which the line of sight to the air brake chambers 
is obscured. In many vehicles, including buses, 
beverage haulers, walk-in vans, ambulances, low- 
bed trucks, utility trailers, and tank-trucks, the 
brake adjustment indicator may only be inspected 
by crawling under a vehicle. Mack explained that 
many vehicle configurations make it difficult or 
impossible to view the chamber from eight feet 
away because brake chambers are frequently 
located in positions that are obscured by tires, 
hoods, and other vehicle components. In addition, 
Rockwell stated that in-service environmental fac- 
tors such as mud, salt, and grease would prevent 
the reading of the adjustment indicator unless the 
chamber were wiped off. 

These practicability concerns with the proposed 
visibility requirements led commenters to rec- 
ommend modifying the proposal. GM rec- 
ommended a simplified requirement in which the 
indicator would have to be discernible when 
viewed with 20/40 vision from outside or the 
underside of the vehicle. Ford suggested that the 



visibility requirement allow inspection from either 
side of or under the vehicle. 

After reviewing the comments, NHTSA has^ 
decided not to adopt the detailed visibility pro- 
posal because the requirement would raise signifi- 
cant practicability problems. The agency notes 
that the proposed eight foot requirement would 
necessitate extensive redesign of certain vehicle 
configurations such as drop floor and moving 
vans. In addition, the proposed visibility require- 
ment would be impracticable for evaluating brake 
adjusters that have been covered by road contami- 
nants such as dirt, grime, and snow. NHTSA 
believes that by not adopting the eight foot view- 
ing requirement, the standard will encourage 
closer hands-on inspection of the equipment. 
Based on the above considerations, the agency 
has decided not to require that the adjustment 
indicator be readable at a distance of eight feet. 
The visibility provision now states that "the 
condition of service brake under-adjustment shall 
be provided by a brake adjustment indicator that 
is discernible when viewed with 20/40 vision 
from a location adjacent to or underneath the 
vehicle." 

d. Vehicle Type ^ 

The NPRM proposed that all air-braked 
vehicles be equipped with an adjustment indica- 
tor, regardless of brake system type. The NPRM 
explained that there were three principal types of 
air brake systems: S cam brakes which account 
for 95 percent of the brake market; wedge type 
brakes, three percent of the market; and disc 
brakes, two percent of the market. While S cam 
brakes have external adjustment mechanisms, 
wedge brakes and some disc brakes have internal 
mechanisms. 

Several commenters, including Volvo GM 
Heavy Truck, Navistar, GM, Bendix, Rockwell, 
and MVMA, stated that adjustment indicators are 
only practicable with external adjustment designs 
such as S cam brakes with exposed push rods. 
MVMA stated that there was little if any need to 
require adjustment indicators on internally 
adjusted brakes. Like hydraulic brakes, air-brake 
systems with internal adjustment designs would 
have to be significantly redesigned to incorporate 
an adjustment indicator. Rockwell believed that 
the nominal benefits from having wedge brakes 
and internally adjusted disc brakes equipped with 
indicators did not wanant the significant costs 
that would be needed to redesign these systems. 



PART 571; S105— PRE-lli 



Bendix and Lear Siegler explained that some 

(external actuators are equipped with a protective 
boot or a scraper seal. 

After reviewing the comments and the available 
information. NHTSA has determined that 
although all air brakes should have a system of 
automatic adjustment, it is not necessary to 
require adjustment indicators on internally 
adjusted brakes. The agency is not aware of any 
significant adjustment problems with internally 
adjusted brakes. In addition, such a requirement 
for these designs would not be practicable given 
the significant feasibility concerns and redesign 
costs to require an adjustment indicator on 
internally adjusted brake systems. The agency 
notes that S cam brakes, except the approximately 
one percent that have protective pushrod boots, 
have exposed air chamber pushrods which easily 
can be marked to indicate brake adjustment. 

S cam brakes whose pushrods are covered 
by protective boots cannot be simply marked, 
since the markings would not be visible to outside 
inspection. The NPRM did not propose to exempt 
booted systems from having to have adjustment 
indicators, describing two designs that have the 
potential to indicate adjustment of such systems. 
In commenting to the docket, Lear Siegler, a 
major air chamber manufacturer, stated that air 
brake actuators equipped with protective boots 
should be exempt from adjustment indication in 
its current technological form. Bendix commented 
that brake actuators with pushrod boots or scraper 
seals should be exempted. 

After a review of the comments to the docket 
and other information on this issue, the agency 
has decided not to require adjustment indicators 
on service brake systems that have pushrod boots. 
Systems having scraper seals and exposed 
pushrods will be required to have adjustment 
indicators, since the pushrods can be easily 
marked and inspected. Brake acmators with 
pushrod boots are made to provide performance 
and reliability under severe operating conditions, 
such as corrosive or hazardous material handling 
and refuse collection and disposal. The heavy- 
duty, durable adjustment indicators, adequately 
integrated into the actuator system, that would be 
necessary to withstand these severe operating 
environments, would cost substantially more than 
indicators on exposed pushrods. Brake systems 
with pushrod boots account for perhaps one per- 
cent of the brake actuator market, as previously 



noted. These systems are being required to have 
automatic brake adjusters. Further, many booted 
systems are used with rolling diaphragm brake 
chambers (roto chambers) that have longer strokes 
than conventional chambers and thus provide a 
greater operating range for automatic slack adjust- 
ers and a longer period of use before the 
underadjustment condition is reached. While the 
agency is not requiring brake systems with booted 
pushrods to have adjustment indicators, it would 
revisit this issue if the number of these systems 
increase substantially in the future. Thus, the 
agency is only requiring externally adjusted 
brakes with exposed pushrods to be equipped 
with adjustment indicators. The agency estimates 
that about 94 percent of air brakes will be 
equipped with indicators. 

3. Miscellaneous Concerns 

Several commenters, including brake indicator 
manufacturers and user groups, requested that the 
agency require air-braked vehicles that are cur- 
rently in use to be retrofitted with automatic 
adjusters and adjustment indicators. NHTSA notes 
that the National Traffic and Motor Vehicle 
Safety Act of 1966 (15 U.S.C. 1381) authorizes 
the agency to promulgate safety standards for new 
vehicles only. The Act does not provide the 
agency with out authority to require the retro- 
fitting of in-use vehicles. Therefore, the agency 
cannot require in-use vehicles to be equipped with 
automatic brake adjusters or adjustment indica- 
tors. 

Flxible commented that it should be allowed 
the option of using manual slack adjusters during 
its certification testing. NHTSA notes that Flxible 
can do whatever it wants in its compliance test- 
ing, if it can establish, should it become necessary 
to do so, that use of its test procedure constitutes 
due care. Nevertheless, NHTSA believes that 
Flxible may have difficulty establishing due care 
if it uses manual adjusters during its certification 
testing, because an earlier rulemaking prohibited 
the disconnecting of automatic adjusters during 
agency compliance testing. (54 FR 40080, 
September 28, 1989). That notice explained that 
an important purpose behind the test conditions 
and procedures is to test vehicles as they will per- 
form when used on the road. Since automatic 
brake adjusters are operational during normal use, 
specifying that they be operational during agency 
compliance testing helps approximate real-world 



PART 571: S105— PRE-1 19 



conditions and provides a better test of real-world 
performance. 

Advocates for Highway and Auto Safety asked 
whether dollies are required to be equipped with 
automatic adjusters and adjustment indicators 
under the proposals. The requirement for auto- 
matic adjusters and adjustment indicators is 
applicable to dollies since section 571.3 defines a 
"trailer converter dolly" as "a trailer chassis 
equipped with one or more axles, a lower half of 
a fifth wheel and a drawbar." Since trailer chassis 
are trailers and trailers are subject to the require- 
ment, trailer converter dollies also are subject to 
the requirement. 

The ATA requested an exclusion from the 
automatic adjuster requirements for vehicles 
involved in "permit" operations such as 
transporting hazardous waste and explosives. 
While NHTSA has the authority to set standards 
based on vehicle type, it does not typically have 
the authority to set standards based on end use 
(aside from school buses). Even if it had such 
authority, vehicle manufacturers could not predict, 
in many instances, which vehicles were ultimately 
going to be used for permit operations and thus 
could not identify which vehicles were excluded. 
Many vehicles used in permit operations are 
standard trucks and trailers with no special fea- 
tures. If the agency were to attempt to exclude the 
permit operation vehicles by excluding whole 
vehicle types, the exclusion would be overbroad. 
The agency notes that a variety of vehicle types 
are used for these permit operations, and if 
NHTSA were to exclude all of these types, it 
would be excluding many vehicles not used for 
permit operations. In addition, the professed rea- 
son to exclude vehicles in permit operations (i.e., 
the presumed frequency of manual brake adjust- 
ments) can be accomplished with brakes equipped 
with automatic adjusters. Some truckers involved 
in dangerous activities adjust their brakes every 
day instead of relying on their automatic adjust- 
ers, because automatic adjusters are equipped with 
external adjusting mechanisms similar to the man- 
ual adjusters. Therefore, if a permit hauler desires 
to adjust its brakes manually, it can do so. Based 
on the above, the agency believes that heavy 
haulers involved in permit operations should be 
required to comply with the automatic adjustment 
requirements. 

International Transquip recommended a salt 
spray test and a stroke cycle test for accuracy. 



performance, and readability. NHTSA notes that 
these tests were not proposed in the NPRM and 
does not believe they are necessary at this time. 
The agency believes that a safety need for these 
additional requirements could not be established. 
In addition, the existing SAE Recommended Prac- 
tice on automatic adjusters already requires 
environmental chamber tests along with cycle 
testing. If additional information indicated that 
these tests would provide significant safety bene- 
fits at reasonable costs, the agency would con- 
sider proposing them. 

MGM Brakes commented that the SAE Truck 
and Bus Brake Actuator Sub-Committee has writ- 
ten and approved a recommended practice for 
cam or disc brake actuators. However, the SAE 
has withheld this document from publication 
because its policy is to not publish any rec- 
ommended practice that will require another 
manufacturer to infringe a patent. Apparently, one 
air brake actuator manufacturer was recently 
issued a patent on a stroke indicator marking sys- 
tem. Notwithstanding the SAE's concern about 
patent infringement, NHTSA notes that this rule 
specifies a general performance standard. There- 
fore, the agency does not anticipate that restric- 
tions caused by patents will be a problem because 
there are many different indicator designs and air 
chamber push rods may be marked in many ways. 

HydrauUcally-Braked Systems 

1 . Brake Adjusters 

The NPRM discussed the need for automatic 
brake adjusters on hydraulically-braked vehicles, 
including passenger cars. The notice explained 
that all new passenger cars have been manufac- 
tured with automatic adjusters for several years. 
The agency stated that such a requirement would 
be consistent with the agency's proposal in Stand- 
ard No. 135 about international brake harmoni- 
zation (52 PR 1474, January 14, 1987, 56 PR 
30528, July 3, 1991). The proposal requested 
comments on whether passenger cars should be 
covered by this amendment to Standard No. 105. 
The proposal also requested comment about 
whether other hydraulically-braked vehicles 
should be required to have automatic brake 
adjusters. 

No commenter expressly supported equipping 
passenger cars and other hydraulic braked 
vehicles with automatic brake adjusters. However, 
several commenters, including General Motors 



PART 571; SI 05— PRE- 120 



and the Motor Vehicle Manufacturers Association 
(MVMA), implicitly supported this requirement 
by commenting that an immediate effective date 
for such vehicles was feasible, provided that the 
requirements did not require the development of 
new designs. Chrysler and Toyota questioned the 
need for such a requirement, claiming that 
hydraulically-braked vehicles are already 
equipped with such devices. 

In addition, Ford and GM commented that, in 
the interests of international brake harmonization, 
the requirements about brake adjusters in Stand- 
ard No. 105 and 135 should be identical. This 
consideration led Ford to state that the proposal 
in Standard No. 10105 about automatic correction 
for over-adjustment was not needed. 

After reviewing these comments. NHTSA has 
determined that Standard No. 105 should be 
amended to require automatic brake adjusters. 
Because vehicles subject to Standard No. 105 
typically are equipped with these devices, the 
agency does not anticipate that the requirement 
would pose a burden on manufacturers. In addi- 
tion, amending Standard No. 105 to require these 
devices will result in consistency between that 
Standard and Standard No. 135. The agency notes 
that such consistency is important because under 
the Standard No. 135 proposal, a manufacturer 
could comply with either standard during the five- 
year phase-in period for Standard No. 135. 

2. Adjustment Indicators 

The NPRM stated that even though brake 
adjusters would be required on hydraulically- 
braked vehicles, automatic adjustment indicators 
would not be required on these vehicles. The 
notice explained that the agency believed that 
there were no significant problems with automatic 
brake adjusters for hydraulically-braked vehicles 
or with checking the adjustment of the brakes on 
such vehicles. Nevertheless, the agency requested 
comments about whether adjustment indicators 
should be required on hydraulically-braked 
vehicles. 

Chrysler believed that allowing continued vol- 
untary compliance would be more appropriate 
than mandating installation through rulemaking. 
GM and MVMA stated that indicators should not 
be required on hydraulic brakes because no safety 
need for such a requirement has been dem- 
onstrated. 

NHTSA continues to believe that there is no 
significant safety problem with automatic adjust- 



ers for hydraulically-braked vehicles or with 
checking the adjustment of such vehicles. Accord- 
ingly, the agency has decided not to require 
adjustment indicators on hydraulically-braked 
vehicles. 

Effective Date 

The NPRM proposed that the amendments 
become effective two years after promulgation of 
the final rule. The agency proposed the same 
leadtime for both air-braked and hydraulically- 
braked vehicles. 

With respect to automatic brake adjusters on 
air-braked vehicles, the notice explained that most 
truck and bus manufacturers already offer auto- 
matic brake adjusters as standard equipment. The 
agency acknowledged that most truck trailer 
manufacturers do not offer automatic brake 
adjusters as standard equipment; about 30 percent 
of all new trailers are presently ordered with auto- 
matic brake adjusters. In addition, the agency esti- 
mated that about 60 percent of all new medium 
and heavy trucks, buses, and trailers already have 
automatic brake adjusters. NHTSA believed that a 
switch from manual to automatic brake adjusters 
would not require major redesigns of more than 
a few, if any, vehicles because automatic brake 
adjusters are already available for most vehicles 
with manual adjusters and the overall brake sys- 
tem is about the same size, with or without auto- 
matic adjusters. The NPRM further stated that 
manufacturers of automatic brake adjusters could 
easily supply enough adjusters to equip all new 
air-braked trucks, buses, and trailers within two 
years. 

The NPRM also stated that two years was 
sufficient leadtime for the brake adjustment 
indicator requirement, noting that two major air 
brake manufacturers, with over 75 percent of the 
market, already mark their push rods with a visual 
indicator for under-adjustment. The notice stated 
that other manufacturers should be able to 
develop a brake adjustment indicator within two 
years. The agency requested comments on the 
adequacy of the leadtime generally and specifi- 
cally for any particular types of vehicles or brake 
systems which would require extensive redesign. 
The notice explained that the agency would con- 
sider providing longer leadtime for vehicles or 
brake systems which needed additional leadtime. 

Thirteen commenters addressed the proposed 
leadtime for requiring brake adjusters and adjust- 



PART571;S105— PRE-121 



ment indicators on air-braked vehicles. The Inter- 
national Brotherhood of Teamsters and a brake 
consultant believed that a leadtime of one year or 
less was appropriate, claiming that the equipment 
is already available. Haldex stated that a one year 
lead time would be possible provided that the 
issue of adjustment indicators was separated. Sev- 
eral commenters, including Ford, the National 
School Transportation Association (NSTA), the 
American Petroleum Institute, the Owner-Operator 
Independent Drivers Association, TTMA, GM, 
and MVMA believed that the proposed two year 
leadtime was appropriate for requirements similar 
to those being adopted in this final rule. Chrysler 
believed that leadtime of three years would be 
necessary for some manufacturers to develop 
automatic adjusters and indicators. 

NHTSA continues to believe that a two year 
leadtime will provide manufacturers adequate 
time to equip air-braked vehicles with brake 
adjusters and adjustment indicators. The agency 
notes that the final rule omits several provisions 
that would have raised significant practicability 
concerns for some vehicle and brake designs. 
NHTSA further notes that although some manu- 
facturers already comply or could quickly bring 
their vehicles into compliance with the require- 
ments, a significant number of small trailer manu- 
facturers would have difficulty complying with 
the amendments unless a two year leadtime is 
provided. 

As for hydraulically-braked vehicles, the notice 
also proposed that the amendment become effec- 
tive two years after publication of the final rule. 
The NPRM requested comment on whether a 
shorter leadtime for hydraulically-braked vehicles 
was appropriate since these vehicles are typically 
produced with automatic brake adjusters. 

GM and MVMA stated that an immediate 
effective date for hydraulically-braked vehicles 
would be acceptable, provided that the amend- 
ments did not require the development of new 
designs. Ford stated that the two year time period 
was more than adequate. No commenter requested 
a leadtime for hydraulically-braked vehicles 
longer than two years. 

Based on the comments and available informa- 
tion, NHTSA has determined that a one year lead- 
time is appropriate for requiring automatic adjust- 
ers on hydraulically-braked vehicles. Those com- 
menters that addressed the issue indicated that an 
immediate effective date would be acceptable. No 



commenter stated that an effective date longer 
than one year was necessary or that a one year 
leadtime would pose an unreasonable burden. 
Based on its review of hydraulically-braked 
vehicles, NHTSA believes that all such passenger 
cars and light trucks are equipped with an auto- 
matic adjuster. As for hydraulically-braked 
medium and heavy duty vehicles, the agency 
notes that these vehicles are typically manufac- 
tured by specialty manufacturers that purchase the 
axle sets and brake components from major 
manufacturers. The agency believes that the major 
manufacturers or trade groups representing the 
specialty manufacturers would have expressed 
their concern if a shorter leadtime had posed a 
hardship. 

This final rule does not have any retroactive 
effect. Under section 103(d) of the National Traf- 
fic and Motor Vehicle Safety Act (15 U.S.C. 
1392(d)), whenever a Federal motor vehicle safety 
standard is in effect, a state may not adopt or 
maintain a safety standard applicable to the same 
aspect of performance which is not identical to 
the Federal standard. Section 105 of the Act (15 
U.S.C. 1394) sets forth a procedure for judicial 
review of final rules establishing, amending or 
revoking Federal motor vehicle safety standards. 
That section does not require submission of a 
petition for reconsideration or other administrative 
proceedings before parties may file suit in court. 

Part 571— [Amended] 

In consideration of the foregoing, 49 CFR Part 
571 is amended as follows: 

1. The authority citation for Part 571 continues 
to read as follows: 

Authority: 15 U.S.C. 1392, 1401, 1403. 1407; 
delegation of authority at 49 CFR 1 .50. 

§571.105 [Amended] 

2. S5.1 of §571.105 is amended by adding the 
following after the current heading: 

Each vehicle shall be equipped with a service 
brake system acting on all wheels. Wear of the 
service brake shall be compensated for by means 
of a system of automatic adjustment. 

§571.121 [Amended] 

3. S5.1.8 of §571.121 is revised to read as fol- 
lows: 



PART 571: S105— PRE-122 



S5.1.8 Brake distribution and automatic adjust- 
ment. Each vehicle shall be equipped with a serv- 
ice brake system acting on all wheels. 

(a) Brake adjuster. Wear of the service brakes 
shall be compensated for by means of a system 
of automatic adjustment. The readjustment limits 
shall be in accordance with those specified in 
Appendix G to Subchapter B of Chapter III - 
"Minimum Periodic Inspection Standards,"' 49 
CFR Parts 200 to 399. 

(b) Brake indicator. For each brake equipped 
with an external automatic adjustment mechanism 
and having an exposed pushrod, the condition of 
service brake under-adjustment shall be displayed 
by a brake adjustment indicator that is discernible 
when viewed with 20/40 vision from a location 
adjacent to or underneath the vehicle. 

4. S5.2.2 of §571.121 is revised to read as fol- 
lows: 

S5.2.2 Brake distribution and automatic adjust- 
ment. Each vehicle shall be equipped with a serv- 
ice brake system acting on all wheels. 



(a) Brake Adjuster. Wear of the service brakes 
shall be compensated for by means of a system 
of automatic adjustment. The readjustment limits 
shall be in accordance with those specified in 
Appendix G to Subchapter B of Chapter III — 
"Minimum Periodic Inspection Standards," 49 
CFR Parts 200 to 399. 

(b) Brake Indicator. For each brake equipped 
with an external automatic adjustment mechanism 
and having an exposed pushrod, the condition of 
service brake under-adjustment shall be displayed 
by a brake adjustment indicator in a manner that 
is discernible when viewed with 20/40 vision 
from a location adjacent to or underneath the 
vehicle. 

Issued on October 14, 1992. 



Marion C. Blakey 
Administrator 



57 F.R. 47793 
October 20, 1992 



PART 571; S105— PRE-123 



MOTOR VEHICLE SAFETY STANDARD NO. 
Hydraulic Brake Systems 



105 



51. Scope. This standard specifies requirements 
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. 

53. Application. This standard applies to pas- 
senger cars, multipurpose passenger vehilces, 
trucks, and buses with hydraulic service brake sys- 
tems. 

54. Definitions. Antilock system means a portion 
of a service brake system that automatically con- 
trols the degree of rotational wheel slip 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 opera- 
tor 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 
therugh 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 transitting 
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 500 
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). 

Parking mechanism means a component or sub- 
system 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 Amer- 
ican Society for Testing and laterials (ASTM) 
Method E-274-70 (as revised July, 1974) at 40 
mph, omitting water delivery as specified in para- 
graphs 7. 1 and 7.2 of that method. 

Snub means the braking deceleration of a 
vehicle from a higher reference speed to a lover 
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. 

Split service brake system means a brake sys- 
tem consisting of two or more subsystems 
actuated 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-sys- 
tems) shall not impair the operation of any other 
subsystem. 

Stopping distance means the distance traveled 
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 



PART 571; S 105-1 



axle loading and/or dynamic weight transfer 
between axles during deceleration. 

S5. Requirements. 

S5.1 Service brake systems. [Each vehicle 
shall be equipped with a service brake system act- 
ing on all wheels. Wear of the service brake shall 
be compensated for by means of a system of auto- 
matic adjustment. (57 F.R. 47793— October 20, 
1992. Effective: October 20, 1993)] 

S5.1.1 Stopping distance. The service brakes 
shall be capable of stopping each vehicle, other 
than a vehicle which both has a GVV/R of not less 
than 8,000 pounds and not greater than 10,000 
pounds and is not a school bus, in four effective- 
ness tests within the distances and from thespeeds 
specified in S5. 1.1.1, S5.1.1.2, S5.1.1.3, and 
S5.1.1.4. 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 
effectiveness tests within the distances and from 
the speeds specified in S5. 1.1.1, S5.1.1.2, and 
S5.1.1.4. 

S.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 dis- 
tances specified in Column I of Table II. 

S5.1.1.2 In the second effectiveness test, the 
vehicle shall be capable of stopping from 30 and 
60 mph within the corresponding distances speci- 



fied in Column II of Table II. If the speed attain- 
able in 2 miles is not less than 84 mph. a pas- 
senger 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. 

55.1.1.3 In the third effectiveness test the vehicle 
shall be capable of stopping at lightly loaded 
vehicle weight from 60 mph within the cor- 
responding distance specified in Column III of 
Table II. 

55.1.1.4 In the fourth effectiveness test, a vehicle 
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 7 Table II. If the speed attainable in 2 miles is 
not less than 84 mph, a passenger-car lor other 
vehicle with a GVWR of 10,000 lbs. or less shall 
also be capable of stopping from 80 mph within 
the corresponding distance specified in Column I 
of Table II. 

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 
indicated below, within the corresponding dis- 
tance specified in Column I of Table II. 



Speed attainable in 2 miles (mph) 



Required to stop 
from (mph) 



Not less than 99 but less than 104 
104 or more 



TABLE I— BRAKE TEST PROCEDURE SEQUENCE AND REQUIREMENTS 



Sequ 



Light 



Test Procedure 



Instrumentation check 

First (prebumish) effectiveness test 

Burnish procedure 

Second effectiveness 

First rebumish 

Parking brake 

Third effectiveness (lightly loaded vehicle) 

Partial failure 

Inoperative brake power and power assist ur 

First fade and recovery 

Second rebumish 

Second fade and recovery 

Third rebumish 

Fourth effectiveness 

Water recovery 

Spike stops 

Final inspection 

Moving barrier test 



S7.2 





S7.3 


S5. 1.1.1 


S7.4 




S7.5 


S5.I.1.2 


S7.6 




S7.7 


S5.2 


S7.8 


S5.1.1.3 


S7.9 


S5.1.2 


S7.10 


S5.1.3 


S7.ll 


S5.1.4 


S7.12 


— 


S7.13 


S.'i.l.4 


S7.14 


— 


S7.15 


S5.1.1.4 


S7.16 


S.S.L.'S 


S7.17 


S5.1.6 


S7.18 


S.5.6 


S7.19 


S5.2.2.3 



(Rev. 10/20/92) 



PART 571: S 105-2 



S5.1.2 Partial failure. 

55. 1.2.1 In vehicles manufactured with a spHt 
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 rup- 
ture or leakage type of failure in any component 
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 
requirements of either S5. 1.3.1, S5. 1.3.2, or 
S5. 1.3.4 (chosen at the option of the manufac- 
turer), 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 of the manufacturer). (46 F.R. 55 — January 
2, 1981. Effective: 9/1/83)] 

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 cor- 
responding 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 inop- 
erative, 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 UI, when the 
inoperative 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)] 



[TABLE II— STOPPING DISTANCES 





STOPPING DISTANCE IN FEET FOR TESTS INDICATED 






I 


n 


III 


IV 


Vehicle test 

speed (miles 

per hour) 


1st (prebumish) power and 4th ef- 
fectiveness: spike effectiveness 
check 


2d 
effectiveness 


3d (lightly loaded vehicle) 
effectiveness 


Inoperative brake 
power and power as- 
sist unit: partial failure 




(a) (b) (c) (d) 


(b) 
(a) and (d) 


(a) (b) (c) (d) 


(b) 

(a) and (d) 

(c) 



30 '57 '65 '-69(lst) '88 '54 '57 '81 51 57 65 81 114 130 170 

'2 65 (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 1607 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 tests. -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 



PART 571; S 105-3 



[TABLE III— INOPERATIVE BRAKE POWER ASSIST AND BRAKE POWER UNITS 



Stop No. 



Average Deceleration, FPSPS 



Equivalent Stopping Distance, Feet 



Column 1- 


-brake 


power 


Column 2- 


-brake 


power 


Column 3- 


-brake 


power 


Column 4— brake 


assist 






init 




as 


iSlSt 




power 


uni 




(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 






323 




388 


9.0 




8.5 


II.O 




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 



' 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)] 



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 sys- 
tem, with any one failure in any one unit, shall be 
capable of stopping the vehicle from 60 mph: 

(a) In 10 consecutive stops at an average decel- 
eration 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 units with a backup system, with one brake 
power assist unit or brake power unit inoperative 
and depleted of all reserve capability and with 
only the backup system operating in the failed 
subsystem, 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 
maximum 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. 

55.1.4.3 (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 lim- 
its: 

(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 base- 
line check minus 10 pounds, or 

(B) The average control force for the base- 
line check times 0.60, 

whichever result is lower (but in no case lower 
than 5 pounds). 



(Rev. 1/2/81) 



PART 571; S 105-^ 



(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 applica- 
tion 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 base- 
line check minus 10 pounds, or 

(B) The average control force for the base- 
line 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 forward 
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 capable 
of making five recovery stops from 30 mph at 10 
fpsps for each stop with a control force application 
that falls within the following maximum and mini- 
mum limits: 

(1) A maximum for the first four recovery 
stops of 150 pounds, and for the fifth stop, of 45 
pounds more than the average control force for 
the baseline check (but in no case more than 90 
pounds, except that the maximum control force 
for the fifth stop in the case of a vehicle manufac- 
tured before September 1, 1976, shall be not more 
than plus 60 pounds of the average control force 
for the baseline check) (but in no case more than 
110 pounds). 

(2) A minimum of — 

(A) The average control force for the base- 
line check minus 10 pounds, or 



(B) The average control force for the base- 
line check times 0.60. 
whichever result is lower (but in no case lower 
than 5 pounds). 

(b) After being driven for 2 minutes at a speed 
of 5 mph in any combination of forward and 
reverse directions through a trough having a water 
depth o 6 inches, 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 for each snub, 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 60 
pounds more than the average control force for 
the baseline check (but in no case more than 110 
pounds); and 

(2) A minimum of — 

(A) The average control force for the base- 
line check minus 10 pounds, or 

(B) The average control force for the base- 
line check times 0.60, whichever is lower (but 
in no case lower than 5 pounds). 

S5.1.6 Spike stops. Each vehicle with a GVWR 
of 10,000 lbs. or less shall be capable of making 
10 spike stops from 30 mph, followed by 
effectiveness (check) stops from 60 mph, at least 
one of which shall be within a corresponding stop- 
ping distance specified in Column I of Table II. 

S5.2 Parking brake system. Each vehicle [with 
a GVWR of 10,000 lbs. or less and each school 
bus with a GVWR greater than 10,000 lbs.] shall 
be manufactured with a parking brake system of 
a friction type with a solely mechanical means to 
retain engagement, which shall under the condi- 
tions of S6, when tested according to the proce- 
dures specified in S7, meet the requirements 
specified in S5.2.1, S5.2.2, or S5.2.3 as appro- 
priate, with the system engaged — 

(a) In the case of a [vehicle with a GVWR of 
10,000 lbs. or less] with a force applied to the 
control not to exceed 125 pounds for a foot-oper- 
ated system and 90 pounds for a hand-operated 
system; and 

(b) In the case of a school bus [with a GVWR 
greater than 10,000 lbs.] with a force applied to 
the control not to exceed 150 pounds for a foot- 
operated system and 125 pounds for a hand-oper- 



PART571; S 105-5 



(Rev. 12/21/81) 



ated system. (46 F.R. 61887— December 21, 1981. 
Effective: 9/1/83) 

55.2.1 Except as provided in S5.2.2, the parking 
brake system on a [passenger car and on a school 
bus] with a GVWR of 10.000 pounds or less shall 
be capable of holding the vehicle stationary (to the 
hmit of traction on the braked wheels) for 5 min- 
utes in both a forward and reverse direction on a 
30 percent grade. (46 F.R. 61887— December 21, 
1981. Effective: 9/1/83) 

55.2.2 A vehicle of a type described in S5.2.1 at 
the option of the manufacturer may meet the 
requirements of S5.2.2.I, S5.2.2.2, and S5.2.2.3 
instead of the requirements of S5.2.1 if: 

(a) The vehicle has a transmission or trans- 
mission control which incorporates a parking 
mechanism, and 

(b) The parking mechanism must be engaged 
before the ignition key can be removed. 

55.2.2.1 The vehicle's parking brake and parking 
mechanism, when both are engaged, shall be 
cpable of holding the vehicle stationary (to the 
limit of traction of the braked wheels) for 5 min- 
utes, in both forward and reverse directions, on a 
30 percent grade. 

55.2.2.2 The vehicle's parking brake, with the 
parking mechanism not engaged, shall be capable 
of holding the vehicle stationary for 5 minutes, in 
both forward and reverse directions, on a 20 per- 
cent grade. 

55.2.2.3 With the parking mechanism engaged 
and the parking brake not engaged, the parking 
mechanism shall not disengage or fracture in a 
manner permitting vehicle movement, when the 
vehicle is impacted at each end, on a level surface, 
by a barrier moving at IVi mph. 

55.2.3 The parking brake system on a multipur- 
pose passenger vehicle, truck, and bus (other than 
a school bus) with a GVWR greater than 10,000 
pounds shall be capable of holding the vehicle 
stationary for 5 minutes, in both forward and 
reverse directions, on a 20 percent grade. 

S5.3 Brake system Indicator lamp. Each 
vehicle shall have one or more brake system 
indicator lamps, mounted in front of and in clear 
view of the driver, which meet the requirements of 



S5.3.1 through S5.3.5. However, the options pro- 
vided in S5.3.1(a) shall not apply to a vehicle 
manufactured without a split service brake system: 
such a vehicle shall, to meet the requirements of 
S5.3.1(a), be equipped with a warning indicator 
that activates under the conditions specified in 
S5. 3. 1(a)(4). This warning indicator shall, instead 
of meeting the requirements of S5.3.2 through 
S5.3.5, activate (while the vehicle remains capable 
of meeting the requirements of S5. 1.2.2 and the 
ignition switch is in the "on" position) a continu- 
ous or intermittent audible signal and a flashing 
warning light displaying the words "STOP — 
BRAKE FAILURE" in block capital letters not 
less than one-quarter of an inch in height. 

55.3.1 An indicator lamp shall be activated when 
the ignition (start) switch is in the "on" ("run") 
position and whenever any of conditions (a), (c), 
or (d) occur, or, at the option of the manufacturer, 
whenever any of conditions (b), (c), or (d) occur: 

(a) A gross loss of pressure (such as caused by 
rupture of a brake line but not by a structural fail- 
ure of a housing that is common to two or more 
subsystems) due to one of the following condi- 
tions (chosen at the option of the manufacturer): 

(1) Before or upon application of a differen- 
tial pressure of not more than 225 lb/in- 
between the active and failed brake system 
measured at a master cylinder outlet or a slave 
cylinder outlet. 

(2) Before or upon application of 50 pounds 
of control force upon a fully manual service 
brake. 

(3) Before or upon application of 25 pounds 
of control force upon a service brake with a 
brake power assist unit. 

(4) When the supply pressure in a brake 
power unit drops to a level not less than one- 
half of the noiTnal system pressure. 

(b) A drop in the level of brake fluid in any 
master cylinder reservoir compartment to less 
than the recommended safe level specified by the 
manufacturer or to one-fourth of the fluid capac- 
ity of the reservoir compartment, whichever is 
greater. 

(c) A total functional electrical failure in an 
antilock or variable proportioning brake system. 

(d) Application of the parking brake. 

55.3.2 [(a) Except as provided in paragraph (b) of 
this section, all indicator lamps shall be activated 



(Rev. 12/21/81) 



PART 571; S 105-6 



as a check of lamp function either when the igni- 
tion (start) switch is turned to the "on" (run) 
position when the engine is not running, or when 
the ignition (start) switch is in a position between 
"on" (run) and "start" that is designated by the 
manufacturer as a check position. 

(b) The indicator lamps need not be activated 
when a starter interlock is in operation. (54 F.R. 
40080— September 29, 1989. Effective: September 
1, 1991)] 

55.3.3 Each indicator lamp activated due to a 
condition specified in S5.3.1 shall remain acti- 
vated as long as the condition exists, whenever the 
ignition (start) switch is in the "on" ("run") 
position, whether or not the engine is running. 

55.3.4 When an indicator lamp is activated it may 
be steady burning or flashing. 

S5.3.5(a) (a) Each indicator lamp shall display 
word, words, or abbreviation, in accordance with 
the requirements of Standard No. 101 (49 CFR 
571.101) and/or this section, which shall have let- 
ters not less than '/s-inch high and be legible to 
the driver in daylight when lighted. 

(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) I 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 aditional labeling. 

(A) If a separate indicator lamp is provided for 
gross loss of pressure, the words "Brake Pres- 
sure" 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 contrast- 
ing 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. 

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 mas- 
ter cylinder. Loss of fluid from one compartment 
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 res- 
ervoirs move from a new lining, fully retracted 
position (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 
compartments 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 only the brake sys- 
tem shall have a minimum capacity equivalent to 
the fluid displacement required to charge the sys- 
tem piston(s) or accumulator(s) to normal operat- 
ing 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 adjusted ini- 
tially to the manufacturer's recommended setting) 
to a fully worn, fully applied position. 

55.4.3 Reservoir labeling. Each vehicle shall 
have a brake fluid warning statement that reads as 
follows, in letters at least Vs 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 shall 
be— 

(a) Permanently affixed, engraved. or 
embossed; 



PART 571; S 105-7 



(Rev. 9/29/89) 



(b) Located so as to be visible by direct view, 
either on or within 4 inches of the braice fluid res- 
ervoir filler plug or cap; and 

(c) Of a color that contrasts with its back- 
ground, if it is not engraved or embossed. 

55.5 Antilock and variable proportioning 
bral<e systems. In the event of failure (structural 
or functional) in an antilock or variable propor- 
tioning 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 require- 
ments 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. 
Friction 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 require- 
ments of S5 shall be met under the following 
conditions. Where a range of conditions is speci- 
fied, the vehicle shall be capable of meeting the 
requirements at all points within the range. 

S6.1 Vehicle weight. 

S6.1.1 Other than tests specified at lightly loaded 
vehicle weight in S7.7, S7.8, and S7.9, the vehicle 
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 rat- 
ing, the load required to reach GVWR is placed 



so that the weight on that axle remains the same 
as at lightly loaded vehicle weight. 

S6.1.2 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 pres- 
sure is the pressure recommended by the vehicle 
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, 
S7.11.3.2, and as required for S7.13, the trans- 
mission selector control is in neutral for all decel- 
erations. For all other tests during all decelera- 
tions, 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 run in gear a manual 
transmission 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 tim- 
ing settings are according to the manufacturer's 
recommendations. If the vehicle is equipped with 
an adjustable engine speed governor, it is adjusted 
according to the manufacturer's recommendation. 

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 num- 
ber of 8 1 . Burnish stops are conducted on any sur- 
face. The parking brake test surface is clean, dry 
smooth Portland cement concrete. 



(Rev. 1/2/81) 



PART 571; S 105- 



S6.10 Vehicle position. The vehicle is ahgned 
in the center of the roadway at the start of each 
brake appHcation. Stops, other than spiiie 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, uncon- 
trolled 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), partial failure stops, and inoperative 
brake power or power assist unit stops. (46 F.R. 
55)— January 2, 1981. Effective: 9/1/83) 



S6.11 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 
thermocouple 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, 
thermocouples are installed within one-eighth of 
an inch to one-quarter inch of the groove and as 
close to the center as possible. 




CO DRILL NO. 31 
0.100 MAX DEPTH 
BEFORE GRIND 



Figure 1 — Typical Plug Thermocuple Installations 

PART 571; S 105-9 



(Rev. 1/2/81) 



S6.12 Initial brake temperature. Unless other- 
wise specified, the brake temperature is 150° F to 
200° F. 



equipped with a headlighting ststem designed to 
conform to the requirements of S7.3, S7.4, S7.5, 
or S7.6. 



S6.13 Control forces. Unless otherwise speci- 
fied, 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 
vehicle shall be capable of meeting all the 
applicable requirements of S5 when testing 
according to the procedures and in the sequence 
set forth below, without replacing any brake sys- 
tem part or making any adjustments to the brake 
system other than as pennitted in burnish and 
rebumish procedures 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 procedures 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 may be 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 con- 
strued as adding to the requirements specified in 
S5.1.2 and S5.1.3.) For vehicles manufactured 
before September 1, 1991, automatic adjusters 
may be locked out, at the option of the manufac- 
turer, when the vehicle is prepared for testing. If 
this option is selected, adjusters must remain 
locked out for the entire sequence of tests. For 
vehicles manufactured on or after September 1, 
1991, automatic adjusters must remain activated at 
all times. A vehicle shall be deemed to comply 
with the stopping distance requirements of 55. 1 if 
all 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 within a 
stopping distance that does not exceed the cor- 
responding distance specified in Table II. When 
the transmission selector control is required 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 service 
brakes. (54 F.R. 40080— September 29, 1989. Effec- 
tive: September 1, 1991)] 

S7.1 Brake warming. Each passenger car, multi- 
purpose passenger vehicle, truck and bus shall be 



57.2 Pretest Instrumentation cfieck. Conduct a 
general check of instrumentation by making not 
more than 10 stops from a 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, replace- 
ment, or adjustment is necessary, make not more 
than 10 additional stops or snubs after such repair, 
replacement, or adjustment. 

57.3 Service brake system — first (reburnish) 
effectiveness test. Make six stops from 30 mph. 
Then make six stops from 60 mph. 

57.4 Service brake system— burnish proce- 
dure. 

57.4.1 Vehicles with GVWR of 10,000 pounds 
or less. 

57.4.1.1 Burnish. Burnish the brakes by making 
200 stops from 40 mph at 12 fpsps (the 150 pound 
control force limit does not apply here). The inter- ^' 
val from the start of one service brake application (^ 
to the start of the next shall be either the time nec- 
essary to reduce the initial brake temperature to 
between 230° F and 270° F, or the distance of 1 

mile, whichever occurs first. Accelerate to 40 mph 
after each stop and maintain that speed until mak- 
ing the next stop. 

57.4.1.2 Brake adjustment— post burnish. 

[After burnishing, adjust the brakes in accordance 
with the manufacturer's published recommenda- 
tions. 54 F.R. 40080— September 29, 1989. 
Effective: September I, 1991.)] 

57.4.2 Vehicles with GVWR greater than 
10,000 pounds. 

S7.4.2.1 Burnish. Vehicles manufactured before 
September 1, 1993 may be burnished according to 
the procedures set forth in S 7.4.2. 1(a) or 
S 7.4.2.1(b) of this section, at the manufactures 
option. Vehicles manufactured on or after Septem- 
ber 1, 1993 shall be burnished according to the 
procedures set forth in S 7.4.2. 1(b) of this section. ^ 
(a) Burnish the brakes by making 500 snubs at \^ 
10 fsps in the sequence specified in Table IV and 



PART 571; S 105-10 



within the speed ranges indicated. Except where 
an adjustment is specified, after each braice 
appHcation accelerate 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 attain any speed specified in 1 
mile, continue to accelerate until the speed speci- 
fied is reached or until the vehicle has traveled 
1.5 miles from the initial point of the previous 
brake application, whichever occurs first. If dur- 
ing any of the brake applications specified in 
Table IV the hottest brake reaches 500° F, make 
the remainder of the 500 applications from that 
snub condition, except that a higher or lower snub 
condition shall be followed (up to the 60 mph ini- 
tial speed) as necesary to maintain a hottest brake 
temperature of 500° F±50° F. However, if at a 
snub condition of 40 to 20 mph, the temperature 
of the hottest brake exceeds 550° F, make the 
remainder of the 500 brake applications from that 
snub condition, without regard to the brake 
temperature. The brakes shall be adjusted three 
times during the burnish procedure, in accordance 
with the manufacturer's recommendations, after 
125, 250, and 375 snubs. 



Table IV 



Snub condi- 
tions (highesi 
speed indi- 
cated) 



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 



(b) Burnish the brakes by making 500 snubs 
between 40 mph and 20 mph at a deceleration 
rate of 10 fsps. Except where an adjustment is 
specified, after each brake application accelerate 
to 40 mph 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 the vehicle cannot attain a speed of 40 mph in 
1 mile, continue to accelerate until the vehicle 
reaches 40 mph or until the vehicle has traveled 
1.5 miles from the initial point of the previous 
brake application, whichever occurs first. The 
brakes shall be adjusted three times during the 

t burnish procedure, the accordance with the manu- 
facturer's recommendations, after 125, 250, and 



375 snubs. 



S7.4.2.2 [Brake adjustment — post burnish. After 
burnishing, adjust the brakes in accordance with 
the manufacturer's published recommendations. 
(54 F.R. 40080— September 29, 1989. Effective: 
September 1, 1991)] 

57.5 Service brake system— second effective- 
ness 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. 

57.6 First reburnish. Repeat S7.42 except make 
35 burnish stops or snubs. In the case of vehicles 
burnished in accordance with S7.4.2.1(a) of this 
section, reburnish the vehicle 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 
brake applications from the highest snub condition 
listed in Table IV that will maintain the hottest 
brake temperature a 500° F±50° F. If at a snub 
condition of 40 to 20 mph, the temperature of the 
hottest brake exceeds 550° F, make the remainder 
of the 35 brake applications from the snub condi- 
tion without regard to brake temperature. 

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 
actuation of a hand-operated brake system shall be 
measured at the center of the hand grip area or at 
a distance of I '/i inches from the end of the actu- 
ation lever, as illustrated in Figure 2. 



S7.7 Test procedure for requirements of 
S5.2.1. 

57.7.1.1 Condition the parking brake friction ele- 
ments 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). 

57.7.1.2 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. 



PART 571; S 105-11 



'"^^' »-^,. -if 



LEVER TYPE A 




F = APPLIED 
R = REACTION 



LEVER TYPE B 



Figure 2 — Location for Measuring Brake Application Force (Hand Bral<e) 



S7.7.1.3 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 
applications 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: 

[(a) In the case of a passenger car or other 
vehicle 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)] 



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). 



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. 



S7.7.1.4 Following the application of the parking 
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 station- 
ary, 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. 



57.7.3 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 manufac- 
turer's published recommendations as furnished to 
the purchaser. If no recommendations are fur- 
nished, run the vehicle in an unbumished condi- 



(Rev. 1/2/81) 



PART 571; S 105-12 



57.8 Service brake system-lightly loaded 

• vehicle (third effectiveness) test. Make six stops 
from 60 mph with vehicle at Hghtiy loaded vehicle 
weight. [This test is not applicable 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. 
EfTective: 9/1/83)] 

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 
appropriate for the indicator being tested) nec- 
essary 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 application of the service brake con- 
trol. Restore the service brake system to nonnal at 
^ completion of this test. 

^ S7.9.2 Repeat S7.9.1 for each of the other sub- 
systems. 

57.9.3 Repeat 57.9.1 and 57.9.2 with vehicle at 
GVWR. Restore the service brake system to nor- 
mal 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 inoperative. Dis- 
connect variable proportioning brake system. 
Make four stops, each from 60 mph. If more than 
one antilock or variable proportioning brake sub- 
system is provided, disconnect or render one sub- 
system inoperative and run as above. Restore sys- 
tem to normal at completion 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 vari- 
able proportioning unit is disconnected. 

^ S7.10 Service brake system — Inoperative 
M brake 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 rel- 
evant power supply. Exhaust any residual brake 
power reserve capability of the disconnected sys- 
tem. On vehicles with brake power units, dis- 
connect the primary source of power. Make four 
stops, each from 60 mph, by a continuous applica- 
tion of the service brake control. Restore the sys- 
tem 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 Optional procedures— passenger cars 
only. 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 pressure 
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 pas- 
senger cars (equivalent stoppng distance 646 feet) 
and determine whether the control 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 ele- 
ment 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 



PART 571; S 105-13 



(Rev. 1/2/81) 



in conjunction with a backup system and the 
backup system is activated automatically in the 
event of a primal^ power failure, the backup sys- 
tem is operative during this test. Disconnect the 
primary source of power of one subsystem. Make 
15 stops, each from 60 mph, with the backup sys- 
tem 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, con- 
duct tests of each in turn. 

S7.11 Service brake system— first fade and 
recovery test. 

57.1 1 .1 Baseline check stops or snubs. 

57.1 1.1.1 Vehicles with GVWR of 10,000 
pounds or less. Make three stops from 30 mph 
at 10 fpsps for each stop. Control force readings 
ma be terminated when vehicle speed falls to 5 
mph. Average the maximum brake control force 
required 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. 

S7.1 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 attain- 
able deceleration between 5 and 1 5 fpsps for each 
stop. Establish an initial brake temperature before 
the first brake application of 130° F to 150° F. Ini- 
tial brake temperatures before brake applications 
for subsequent stops are those occurring at the dis- 
tance 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 proce- 
dure specified in S7. 11.3.1. 



S7.1 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 fpsps 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 subsequent snubs are those 
occurring in the time intei-vals specified below. 
Attain the required deceleration within 1 s and 
maintain it for the remainder of the snubbing time. 
Leave an interval of 30 s between snubs (start of 
brake application to start of brake application). 
Accelerate immediately to the initial test speed 
after each snub. Drive for .5mi 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 Ibor 
less. Make five stops from 30 mph at 10 fpsps for 
each stop. Control force readings may be termi- 
nated when vehicle speed falls to 5 mph. Allow 

a braking distance interval of 1 mi. Immediately 
after each stop accelerate at maximum rate to 30 
mph and maintain that speed until making the next 
stop. Record the maximum control force for each ^^ 
stop. 

57.1 1.3.2 Vehicles with GVWR greater than 
10,000 lb. Witn transmission in neutural (or 
declutched) make five snubs from 40 to 20 mph 
at 10 fpsps for each snub. After each snub, accel- 
erate at maximum rate to 40 mph and maintain 
that speed until making the next brake application 
at a point 1.5 mi form the point of the previous 
brake application. Record the maximum control 
force for each snub. 

57.12 Service brake 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) ip. 
make four stops from either 95 mph if the speed \ 
attainable in 2 miles is 99 to (but not including) 



PART 571; S 105-14 



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. 

57.16.1 Baseline clieck 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. 

57.16.2 Wet brake recovery stops. With the 
brakes fully released at all times, drive the vehicle 
for 2 minutes at a speed of 5 mph, in any com- 
bination 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 applica- 
tion. 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 neu- 
tral, with no reverse stops. Make spike stops by 
applying a control force of 200 pounds while 
recording control force versus time. Maintain con- 
trol force until vehicle has stopped. At completion 
of 10 spike stops, make 6 effectiveness stops from 
60 mph. 

87.18 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 
'/32 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. Linings 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 Recommended 
Practice J972 "Moving Barrier Collision Tests," 
November 1966, impact the vehicle from the front 
at IVi mph. Keep the longitudinal axis of the bar- 
rier 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 brakini; 
tests. 



PART 571; S 105-15 



PREAMBLE TO AN AMENDMENT TO FEDERAL MOTOR VEHICLE SAFETY 
STANDARD NO. 108 

Lamps, Reflective Devices, and Associated Equipment 

Docket No. 80-9; Notice 6 
RIN2127-AA12 



AGENCY: National Highway Traffic Safety 
Administration (NHTSA), DOT 

ACTION: Final rule. 

SUMMARY: This notice requires that trailers 
which have an overall width of 80 inches or more 
and a GVWR of more than 10,000 pounds, except 
trailers manufactured exclusively for use as offices 
or dwellings, be equipped on the sides and rear 
with means for increasing their conspicuity. This 
will enhance the likelihood of their detection at 
night and under other conditions of reduced visi- 
bility. Trailer manufacturers will be given a choice 
of installing either retroreflective sheeting or 
reflex reflectors. Under the rule, manufacturers of 
retroreflective sheeting or reflectors will certify 
compliance of their product with Standard No. 
108, whether for use as original or as replacement 
equipment. NHTSA estimates that the incidence of 
accidents involving trailers struck in the side or 
rear by other vehicles could be reduced 15 percent 
by enhancing conspicuity as required by this rule. 

DATES: The effective date for the rule is Decem- 
ber 1, 1993. Petitions for reconsideration of the 
rule must be received not later than 30 days after 
the rule is published in the Federal Register. 

ADDRESS: Petitions for reconsideration should 
refer to Docket 80-9; Notice 6, and be submitted 
to: Administrator, Docket Section, Room 5109, 
Nassif Building, 400 Seventh Street, SW, 
Washington DC 20590 (Docket hours are from 
9:30 a.m. to 4 p.m.) 

FOR FURTHER INFORMATION CONTACT: Pat- 
rick Boyd, Office of Rulemaking (202-366-6346). 

SUPPLEMENTARY INFORMATION: On Decem- 
ber 4, 1991, NHTSA published a notice of pro- 



posed rulemaking (NPRM) addressed to making 
large trailers more visible on the road (56 FR 
63474). The NPRM represented a tentative and 
partial solution to a safety problem that has con- 
cerned NHTSA for some years: the need to reduce 
the incidence and severity of collisions with large 
trailers during darkness or reduced visibility. As 
early as May 27, 1980, the agency showed its 
interest in enhanced conspicuity as a possible 
solution. NHTSA issued an ANPRM (45 FR 
35405) requesting comments on methods to 
reduce such collisions by improving the conspicu- 
ity of large commercial vehicles. Forty-two com- 
ments were received, most of which favored the 
concept. 

NHTSA Fleet Study 
Between 1980 and 1985, the agency conducted 
a fleet study in which retroreflective material was 
placed on truck-van trailer combinations in a 
manner designed to increase their conspicuity. 
The treatment of trailers consisted of outlining the 
rear perimeter, and delineating the lower side. No 
reflectorized mud flaps were used. The contractor 
concluded that truck-trailer combinations 
equipped with this material were involved in 15 
percent fewer crashes (in which a trailer was 
struck in the side or rear) than combinations lack- 
ing the material. 

1987 Request for Comments 
The agency published a Notice of Request for 
Comments on September 18, 1987 (52 FR 35345) 
concerning the use of reflective material to 
increase the conspicuity of large trucks and trail- 
ers. The Notice recited the results of the fleet 
study and sought comments on the test results as 
well as the experiences others may have had with 
the use of reflective material to enhance conspicu- 
ity. Thirty-seven comments were received, most 
agreeing that an effectiveness of 15 percent could 



PART 571; S 108— PRE-391 



be expected when all large vehicles were so 
equipped with reflective material. 

The Motor Carrier Safety Act of 1990 
In response to the NHTSA fleet study. Con- 
gress included in the Motor Carrier Safety Act of 
1990 (Sec. 15, P.L. 101-500) a provision directing 
the Secretary of Transportation "to initiate a rule- 
making proceeding on the need to adopt methods 
for making trucks or any category of trucks more 
visible to motorists. . ."' not later than February 
3, 1991, and to complete the rulemaking proceed- 
ing not later than November 3, 1992. 

The 1991 NPRM 

NHTSA regards its 1991 NPRM, which is part 
of a mlemaking proceeding begun before the 
enactment of the Motor Carrier Safety Act of 
1990, as responsive to the directive in that Act, 
and this notice as the completion of the rule- 
making proceeding mandated by Congress. Under 
the NPRM, heavy trailers would be required to be 
equipped with means for increasing their con- 
spicuity because the agency tentatively concluded 
that this would be an effective method to reduce 
the incidence and severity of these crashes. The 
proposal did not apply to large trucks without 
trailers, since NHTSA' s PARS (Fatal Accident 
Reporting System) accident data for 1989 
indicated a much lower rate of conspicuity-related 
accidents for large trucks alone than for large 
truck-trailer combinations. The reader is referred 
to the NPRM for a further discussion of the data. 

Eighty-three comments were received in 
response to the NPRM, representing the views of 
manufacturers of vehicles, lamps, reflectors, and 
retroreflective sheeting; commercial and private 
fleet operators; the Teamsters union; States; insur- 
ance companies; and citizens. A Summary of 
Comments has been prepared and is available for 
inspection in the docket. Details of the NPRM, 
issues raised by the comments, and NHTSA's 
responses are discussed below. NHTSA has incor- 
porated recommendations on modifications to the 
proposed retroreflective brightness values in a 
Supplementary Notice of Proposed Rulemaking 
(SNPRM) that is being prepared for publication. 
The SNPRM will also incorporate proposals 
regarding substitution of the retroreflective mate- 
rials required by this notice for existing reflex 
reflectors. 



Effectiveness of Conspicuity Treatment 
There was near unanimity among the com- 
menters that a S retroreflective conspicuity treat- 
ment would prevent accidents and save lives. 
Most of the comments were directed towards the 
details of implementing conspicuity treatment 
rather than questioning its efficacy. The only 
commenter who questioned the possible effective- 
ness was UPS, only commenter who questioned 
the principally because neither it nor its insurers 
were aware of any data concerning conspicuity- 
related accidents. 

However, other commenters reported specific 
data on conspicuity-related accidents and their 
experiences with retroreflective treatments. Amer- 
ican Inter-Fidelity Exchange, an insurer, began in 
August 1990 to require 3M diamond grade mate- 
rial on all insured platform trailers. In the 17- 
month period before August 1990, it had $2 mil- 
lion in claims with injuries and fatalities in con- 
spicuity-related accidents. In the 18-month period 
subsequent to July 1990, it experienced no costs, 
no fatalities and few injuries in conspicuity 
related accidents. The insured fleet numbered 
3,500 flat bed trailers, and the miles traveled 
totalled 3.5 million. Landstar commented that it 
had retrofitted 6,500 trailers of a fleet of 9,000, 
and had experienced a 50 percent reduction in 
underride accidents, and a 90 percent reduction in 
the cost of an average underride accident claim. 
American Trucking Associations (ATA) reported 
on a program to assess the effectiveness of detect- 
ability where a conspicuity treatment was applied 
to 11,000 trailers. It found that the fleet experi- 
enced no conspicuity-related accidents in the year 
since the first application. The effectiveness of 
conspicuity treatment in daytime remains subject 
to question. While the agency is not assuming 
that there is a daytime benefit, it believes that the 
overall effectiveness of retroreflective conspicuity 
treatment is clearly demonstrated by the experi- 
ence of these commenters. 

Types of Trailers to Be Regulated 
Since the various types of trailers differ from 
one another in their configuration, NHTSA ten- 
tatively concluded that the method of compliance 
that may be appropriate for one type may not be 
for another. For example, van-type trailers have 
distinct rectangular side and rear perimeters to 
which conspicuity enhancing materials could be 
easily applied, while tank-type, platform trailers. 



PART 571; S 108— PRE-392 



or others do not. In order to ensure that the 
requirements would be practicable for each type 

• of trailer to which they apply, the agency devel- 
oped and proposed definitions for four types of 
trailers: "Dump," "Flatbed," "Tank," and 
"Van." The requirements proposed for these 
types differed somewhat based on the differences 
in their configurations. Noting that these trailer 
types account for 95 percent of the miles traveled 
by heavy commercial trailers, NHTSA sought 
comment on whether, for the sake of practicabil- 
ity, the remaining 5 percent of trailers (those not 
fitting any of the four proposed definitions) 
should be excluded from compliance with the 
conspicuity treatment requirements. Additionally, 
NHTSA sought comment on the practicability of 
applying conspicuity treatment to car carriers, 
heavy haulers, and intermodal trailers. 

Twenty-four general commenters wanted the 
final rule to include all commercial trailers with- 
out exceptions. They argued that it is preferable 
to allow sufficient latitude in the spacing and 
location of reflective materials that would facili- 
tate compliance by all trailer types, than to 
exclude some specific type on the basis of prac- 

• ticability. 
However, a number of other commenters 
requested that specific trailer types be excluded 
from the final rule. These trailer types were con- 
tainer chassis, automobile transporter, side-loading 
beverage, garbage, shiny aluminum, stainless van, 
and house and recreational. 

NHTSA considered each of these trailer types. 
Container chassis trailers and garbage trailers 
designed for carrying containers are motor 
vehicles for purposes of the lighting standards of 
NHTSA and the Federal Highway Administration 
(FHWA). The sides of these types of trailers are 
easily visible, even if low. Thus, the agency sees 
no reason to exclude container chassis trailers or 
garbage container trailers from the final rule. 
Similarly, reflectorization of frame members 
appears to be a practical solution for trailers with 
bodies routinely covered by tarps, such as some 
platform trailers. 

Some commenters called for marking of 
containers because a container mounted on a con- 
tainer chassis resembles a van trailer. However, a 
commenter representing the container industry 
^ pointed out that the marking of containers is sub- 

P ject to international treaty and that containers 

equipped with conspicuity material would be 



illegal to transport in some countries. Accord- 
ingly, NHTSA has chosen not to require marking 
of containers. 

Commenters recommending an exclusion for 
car transporters pointed out that the transporter 
side rails may be lower than 15 inches and that 
the vehicles transported are equipped with side 
and rear reflex reflectors. However, the reflectors 
on cars being transported on the carrier would not 
provide the trailer with either a recognizable pat- 
tern or a sufficient return of light to satisfy the 
intent of the rule. NHTSA has chosen to allow 
greater flexibility in the minimum mounting 
height of retroreflective materials so that the side 
rails of such vehicles may be equipped with con- 
spicuity materials, if there is no practical alter- 
native. 

With respect to side-loading beverage trailers, 
the rationale for exclusion appears to be based on 
the need to mount retroreflective materials low 
enough to clear the doors. NHTSA believes that 
the minimum mounting height adopted by this 
rule will be low enough to clear the doors, but, 
in any event, neither the NPRM nor the final rule 
prohibit application of conspicuity treatment to 
doors. 

Finally, the agency has considered the request 
to exclude travel and house trailers. NHTSA long 
ago relinquished jurisdiction over mobile homes 
as trailers to the Department of Housing and 
Urban Development. However, the agency does 
regulate travel trailers. They are low mileage 
vehicles that are generally parked off-road at 
night, either on private property or trailer parks. 
NHTSA has concluded that to exclude this type 
of large trailer from the conspicuity requirement 
would not have an adverse effect upon safety. 
Accordingly, S5.7 will specify that the mle 
applies to all large trailers except those that are 
designed exclusively for living or office use. 

The National Marine Manufacturers Associa- 
tion commented that it does not consider its 
small-boat industry to be affected by this rule- 
making action because boats weighing 10,000 
pounds or more are normally carried by commer- 
cial rather than recreational trailers. This is not 
always the case. Boats weighing less than 10,000 
pounds may be carried by recreational trailers 
with GVWRs over 10,000 pounds. Any boat 
trailer whose GVWR exceeds 10,000 pounds will 
be subject to this rule, whether the trailer is 
commercial or recreational. 



PART 571; S 108— PRE-393 



There were also recommendations that trucks 
and truck tractors be required to have conspicuity 
treatments. NHTSA restricted the NPRM to trail- 
ers to assure its cost effectiveness, because it 
appeared that the vast majority of fatal accidents 
in which trucks are struck at night involve tractor 
trailer combinations. The argument for including 
truck tractors is that they are not required to be 
equipped with rear mounted turn signals or rear 
identification lamps, and their tail/stop lamps are 
closer together than on other vehicles. Hence, 
from the rear at least, they are not a conspicuous 
presence on the road at night. Preliminary 
information available from PARS and General 
Estimates System (GES) indicate that there is a 
far higher accident involvement rate at night for 
tractors than for trucks. The foregoing suggests 
that a rear conspicuity treatment for truck tractors 
may provide safety benefits. The agency is 
considering the issue for possible inclusion in a 
future rulemaking. 

Manufacturer Choice of Type of Retroreflective 

Materials 
NHTSA tentatively decided in the NPRM that 
manufacturers of heavy trailers should be required 
to equip them with one of two proposed types of 
retroreflective materials. Compliance would be 
achieved using either retroreflective sheeting, or 
an array of reflex reflectors which reflects the 
same amount of light as the retroreflective sheet- 
ing. Commenters supported the option. As 
explained below, the final rule allows manufactur- 
ers the choice of using retroreflective sheeting or 
reflex reflectors. 

Performance and Location of Retroreflective 
Materials 

NHTSA proposed, as alternatives, two sets of 
requirements regarding pattern, color and location 
for placing retroreflective sheeting on the side and 
rear of trailers. One alternative was the pattern 
tested in the fleet study, and the other was a 
modification of the pattern that was expected to 
increase visibility of the trailer side. Each alter- 
native used about the same amount of 
retroreflective sheeting, so that cost was not an 
issue. However, the second alternative distributed 
it in a way that was more generally applicable to 
all trailers, avoided setting higher standards for 
van trailers, and promoted uniformity of appear- 
ance. Under either alternative, the material would 
not be required to be affixed to discontinuous sur- 



faces on the trailer body, and on items such as 
door hinges, and lamp bodies. While the agency 
proposed two specific configurations of conspicu- 
ity treatment, it specifically sought comment on 
whether variations of these alternatives would be 
more appropriate for a final rule, or whether there 
were other patterns more appropriate for con- 
spicuity that should be proposed before a final 
rule was adopted. NHTSA also asked that com- 
menters discuss the cost-effectiveness of each pat- 
tern, and provide support for their comments. The 
agency anticipated that the final rule would 
specify only one pattern, and not allow alternative 
treatments. Associated issues on which NHTSA 
requested comment were the appropriate level of 
retroreflective performance of the sheeting, the 
appropriate amount of sheeting used, whether the 
sheeting should be patterned, and the appropriate 
location of the sheeting, with respect to each of 
the alternatives. 

Configuration of Retroreflective Sheeting 
For its proposed Alternative 1, the agency 
chose a variation of the scheme used in the 
NHTSA fleet study. Alternative 1 consisted of a 
2-inch wide strip of retroreflective tape in 
alternating red and white rectangles delineating 
the lower side rails and outlining the rear perim- 
eter of the trailer. The white rectangles would be 
7 to 9 inches long, and the adjacent red rectangles 
would be 2 to 4 inches longer than the white 12 
rectangles. The material would be installed on the 
perimeter of the rear of van trailers, and on as 
much of the rear perimeter of other trailers as 
practicable. The material would also be installed 
horizontally on each side to indicate the length of 
the trailer. The length of the material mounted on 
the side inclusive of interruptions for discontinu- 
ous surfaces would be within 3 feet of the full 
length of the trailer. Allowing for interruptions 
due to trailer design, the total length of the 
individual horizontal strips provided would not be 
less than 85 percent of the length of the material 
were there no interruptions. The mounting height 
of the horizontal side strips would be restricted to 
the same height as other retroreflective devices 
currently required by Standard No. 108; the center 
would be not less than 15 inches above the road 
surface; and the upper edge not more than 60 
inches above it. In the NPRM, NHTSA noted 
that, because of their configuration, van trailers 
can best benefit from this type of treatment. The 



PART ,'^7l; S 



-PRE-394 



large, flat surfaces of van trailers give the 
observer a better basis for judgment of size, 
shape, and distance compared with a flat bed 
trailer having only a thin side or rear frame. 

Alternative 2 redistributed the conspicuity 
materials by placing more on the sides of the 
trailers and using only a partial outline on the 
rear. In NHTSA's view, this approach would pro- 
vide better depth perception to the drivers of 
vehicles approaching the trailer from the sides 
and create a more standardized treatment across 
trailer categories without requiring the use of 
more conspicuity materials. In addition, this 
approach would avoid "penalizing" van trailers 
which, because of their large and flat surfaces, 
would require, under Alternative 1, a greater use 
of reflective materials than other trailer types. 
Alternative 2 would provide slightly better side 
recognition distance than Alternative 1, and iden- 
tical rear recognition distance, as demonstrated by 
laboratory and field results from an ongoing 
University of Michigan Transportation Research 
Institute (UMTRI) research for NHTSA (Contract 
No. DTNH22-90-C-07017). Under both Alter- 
native 1 and Alternative 2, red and white material 
would be required to be installed horizontally on 
each side to indicate the length of the trailer. 
However, on the rear, the only red and white 
material required by Alternative 2 would be at the 
base of the perimeter, rather than the entire 
perimeter as required by Alternative 1. In addi- 
tion. Alternative 2 would require two vertical 
white strips 12 inches high and 2 inches wide, to 
indicate the width of the trailer, located within 12 
inches of its full width. Similarly, two vertical 
white strips would be located on the side, as close 
to the front and rear as practicable, to indicate the 
full length of the trailer. In addition, the upper 
comers of the rear and both sides would be 
required to be marked with two intersecting 
pieces of white reflective sheeting, each 12 inches 
by 2 inches. On the rectangular sides and rear of 
a van trailer, the white strips, along with the red 
and white base strips, would mark the bottom and 
four corners of the sides and rear. However, 
under Alternative 2, the white strips could also be 
applied to trailers of irregular shape because they 
would not be required to form a continuous 
perimeter. White strips of sheeting would also be 
added to the vertical members of the rear 
underride protection equipment. Finally, white 
sheeting 36 inches long and not less than 2 inches 



high would be installed horizontally at the top 
center of the trailer sides. 

After consideration of the comments, and for 
the reasons set forth below, NHTSA has decided 
to adopt the side conspicuity configuration of 
Alternative 1, and a rear conspicuity configuration 
similar to Alternative 2. 

Alternative 1 was preferred by the U.S. Postal 
Service and Peterson Manufacturing. Alternative 2 
was the choice of the National Private Truck 
Council, Idaho State Police, National Automobile 
Dealers Association, New Jersey Motor Vehicle 
Administration, Minnesota Department of 
Transportation, Wolf Technical Services, Dr. 
Rudolf Mortimer, Insurance Institute for Highway 
Safety, and Advocates for Highway & Auto 
Safety. Other commenters suggested combining 
elements of the two Alternatives. Many com- 
menters desired discontinuous side striping to 
reduce material expense, to accommodate irregu- 
lar surfaces and to simplify repair. 

NHTSA believes that an effective configuration 
must identify the vehicle unambiguously as a 
trailer, and allow an estimate of its size and the 
closing distance to it. Given the decision to 
include all large trailers (except house trailers), 
practicability concerns require that the rule have 
enough flexibility to be applied to all trailers. The 
reduced detail of a more flexible rule creates a 
greater dependence on the common sense of 
trailer manufacturers to use materials in an effec- 
tive way. The present widespread voluntary use of 
conspicuity materials well adapted to the struc- 
tures of various types of trailers gives the agency 
confidence that a more flexible rule will be effec- 
tive. 

It is for this reason that NHTSA has chosen the 
side conspicuity treatment of Alternative 1 and a 
rear treatment similar to Alternative 2. The use of 
broken side stripes, with at least 50 percent of the 
length of the trailer covered, will make it prac- 
ticable for ribbed trailers, and trailers with sides 
partially obscured by equipment, to conform. 
Under the rule, the distribution of spaces and 
material must be as uniform as practicable and 
indicate the full length and width of the trailer, 
but they may be arranged to fit the structure of 
the trailer. The colors must be placed in alternat- 
ing sequence with no more than two-thirds of the 
material in one color. 

Flexibility in the vertical location of stripes is 
necessary to allow lowboys, car carriers, and 



PART 571; S 108— PRE-395 



some tank trailers to comply. In order to promote 
uniformity without excluding trailer types, the 
stripes should be located for maximum visibility, 
thus the rule requires that they be as close as 
practicable to 4 feet above the road surface (the 
lower edge of the body of the great majority of 
trailers is about 4 feet above the road). Material 
may be placed on trailer doors. NHTSA recog- 
nizes that the location for maximum visibility on 
certain trailers may be the trailer frame. 

The rear treatment of Alternative 2 is a good 
basis for a universal requirement. However, the 
treatment element for the underride device was 
the subject of both positive and negative com- 
ment. Objections were based on the potential for 
frequent damage that would cause trailers in use 
to fail inspections by the FHWA. NHTSA has 
observed that the horizontal bar of the underride 
device is less subject to docking impacts than the 
vertical bars because it is below most dock sur- 
faces (and under a NHTSA proposal would be 
even lower). Therefore, the final rule requires 
retroreflective material to be applied to the hori- 
zontal device, instead of the vertical ones as pro- 
posed. NHTSA believes that the original con- 
spicuity material should have a long useful life on 
a large number of trailers, especially if it is 
applied to a recessed surface. However, NHTSA 
recognizes that routine damage, as a practical 
matter, may be unavoidable for some trailers as a 
consequence of their particular use. Therefore, the 
FHWA will consider the exclusion of conspicuity 
treatment from the rear underride device in any 
future rulemaking concerning trailer conspicuity 
requirements for vehicles subject to 49 CFR Pait 
393 Parts and Accessories Necessary for Safe 
Operation, and 49 CFR Part 396 Inspection and 
Maintenance. 

The rule requires conspicuity treatment of the 
upper corners where they exist. For example, plat- 
form trailers are required by the Motor Carrier 
Safety regulations (49 CFR 393.106) to have a 
front bulkhead, which can carry the upper comer 
treatment. The rear stripe of material will be 
continuous across the rear. To harmonize with 
Motor Carrier Safety regulations (49 CFR 
323.26), a 3-inch spacing between white material 
and rear lamps is required (but red material may 
be used adjacent to lamps to create a full width 
stripe). 

The UMTRI study specifically supports the rear 
treatment of Alternative 2 that has been chosen 



(see Figure 6.1(B) of its research report as cited 
in the NPRM). UMTRI found comparable detec- ^^ 
tion distances between vehicles using a partial (' ~ 
and a full rear outline, and recommended the par- 
tial outline as adequate for the task. 

Although NHTSA' s standards cannot apply to 
vehicles in use, NHTSA believes that the safety 
benefits of conspicuity treatment are so 
demonstratable that fleet owners will wish to 
retrofit their trailers with conspicuity treatment. 
NHTSA recommends that they employ a treat- 
ment that corresponds with the requirements of 
the final rule. Several commenters believe that 
retrofit would be encouraged if NHTSA allowed 
two 1-inch strips of material as an alternative to 
one 2-inch strip. The final rule affords the manu- 
facturer this option. 

Peifonnance of Retroreflective Sheeting 
The NPRM proposed a set of tests to evaluate 
retroreflective sheeting. These tests would be con- 
ducted in accordance with ASTM D 4956-90, 
Standard Specification for Retroreflective Sheet- 
ing for Traffic Control. The ASTM Specification 
was chosen because NHTSA understood it to be 
the Specification that manufacturers of 
retroreflective sheeting were following as their 
current manufacturing practice. The tests that 
NHTSA proposed addressed retroreflective photo- 
metric performance, flexibility, adhesion, impact 
resistance, accelerated weathering, shrinkage, 
resistance to fungus, and specular gloss. Com- 
menters were also asked to discuss the use of 2- 
inch wide white material of a minimum 250 can- 
dela lux/square meter (for entrance angles of light 
up to 30 degrees) as compared with wider, but 
lower performance material or narrower, higher 
performance material. The notice proposed that 
material meeting the performance requirements 
(other than reflectivity) for Type V, defined as a 
super-high-intensity retroreflective sheeting, be 
used to enhance the conspicuity of trailers. It pro- 
posed minimum requirements for coefficients of 
retroreflective intensity from research in progress 
by UMTRI that were lower than those specified 
by ASTM for Type V material. The proposed val- 
ues were shown to be adequate, and more closely 
represented the material fleet tested during the 
Vector study. 

A principal issue that was raised by the com- /^ 
ments was the brightness of the retroreflective V 
material. Brightness is expressed in "specific 



PART 571; S 108— PRE-396 



intensity per unit area" or "SIA."" SIA is speci- 
fied at observation angles of 0.2 degree and 0.5 
degree, and light entrance angles of -4 degrees 
and 30 degrees in both the ASTM specification 
and the NPRM. The NPRM required the same 
minimum performance at both entrance angles, a 
specification intended to simulate a viewing dis- 
tance of 740 feet to a trailer angled at 30 degrees 
with respect to an approaching vehicle. Although 
commercially available retroreflective material 
easily exceeds the proposed minimum perform- 
ance at -4 degrees, the lesser values proposed and 
adopted for that angle adequately meet the need 
for motor vehicle safety. 

There were three questions raised about the 
brightness of the material: whether the higher 
specification of the ASTM should be adopted; 
whether a system of wider stripes of material of 
lower brightness should be allowed; and whether 
a brightness should be specified at an entrance 
angle greater than 30 degrees. 

Insurance Institute of Highway Safety (IIHS), 
Advocates for Highway & Auto Safety (Advo- 
cates), Reflexite, and Transportation Safety 
Equipment Institute (TSEI) supported the ASTM 
specification. IIHS justified its comment by point- 
ing out that the UMTRI study measured sight dis- 
tances in good weather using subjects in a car 
with clean headlamps and windshield. For this 
reason, the proposed material brightness should be 
increased to account for weather and car condi- 
tions. NHTSA disagrees with this argument. The 
values for brightness proposed are actually four 
times greater than the minimum brightness that 
UMTRI measured as adequate under good condi- 
tions specifically to accommodate weather, dirt, 
and other deleterious effects. Accordingly, 
NHTSA has decided not to adopt the higher 
ASTM specification. 

UMTRI also indicated that wider stripes 
of lower performance material would be as effec- 
tive as the proposed material as long as the 
amount of light reflected is preserved. Stimsonite 
and 3M recommended that the final rule allow 
wider material with equal specific intensity per 
linear foot as the proposed 2-inch material. There- 
fore, in the final rule, NHTSA is also allowing 3- 
inch and 4-inch wide materials as options. The 
three materials will be known respectively as 
D0T-C2, D0T-C3 and D0T-C4. These materials 
are believed to have the equivalent specific inten- 



sity per linear foot as those proposed and adopted 
for the 2-inch material. Figure 29 as adopted con- 
tains the SIA values for D0T-C3 and D0T-C4 
materials at the same observation and entrance 
angles as the DOT-C2 materials. 

Several commenters voiced a need for values at 
an entrance angle of 45 degrees, and NHTSA ten- 
tatively concurs. However, since the agency nei- 
ther proposed a particular value nor even raised 
the general issue of a value for that entrance 
angle, NHTSA has included a proposed value in 
the SNPRM that NHTSA is issuing simulta- 
neously with the final rule. It also proposes that 
the SIA value of 10 adopted for D0T-C2 red 
material at the 0.5 degree observation angle and 
entrance angles of -4 degrees and 30 degrees be 
increased from 10 to 15 in order to be more 
consistent with the performance specified at an 
observation angle of 0.2 degree. 

The Rulemaking Analysis section of the NPRM 
stated that the average life of a trailer was 
believed to be 14 years, and that one application 
of the material should be sufficient for the life of 
a trailer. Yellow Freight and Anya Carrol dis- 
agreed. One cited the effects of chipping by 
stones, scrapes by tree limbs and by cleaning 
brushes. The other commented that loss of bright- 
ness will occur in the absence of frequent clean- 
ing of the materials. 

UMTRI investigated material that had been 
installed on fleets for at least 10 years, and found 
a moderate loss of brightness due to age, and a 
larger loss when the material was dirty. Material 
manufacturers routinely guarantee the retention of 
at least 50 percent of their original brightness for 
7 years, while agreeing with UMTRI that the 
service life is much longer. NHTSA' s proposed 
SIA values took into account the effect of age and 
dirt. Further, the agency made an effort to use 
industry standards in the belief that those stand- 
ards represented the best engineering solutions of 
suppliers to the actual requirements of users. 
Thus, no change to the proposal is needed in 
response to considerations of durability or life of 
retroreflective materials. Further, as noted later, 
the FHWA will consider maintenance of the con- 
spicuity treatment in any future rulemaking to 
adopt the conspicuity requirements in the Federal 
Motor Carrier Safety Regulations. 



PART 571; S 108— PRE-397 



Comments on Dimensions and Color of 
Retroreflective Sheeting 

With respect to retroreflective materials, 
NHTSA requested views on the proposed length 
and width of the red and white segments. NHTSA 
noted that it was not proposing to allow corporate 
logos as a substitute for the conspicuity materials. 
Typically, logos consist of material of low bright- 
ness, and they are not applied to the perimeters 
of a vehicle but are centered on the sides and 
rear. Logos may be used to supplement the con- 
spicuity-enhancing materials that would be 
required, however. 

With respect to the requirements of Alternative 
1 and Alternative 2 regarding pattern, color and 
location, the agency sought comments on the 
likely relative effectiveness of each on van trail- 
ers, and on trailers other than van trailers. 

With respect to Alternative 2, NHTSA asked 
for views on whether it would improve or detract 
from the side conspicuity of trailers as compared 
with Alternative 1, and whether the 12-inch long 
segments of white material contemplated should 
be increased to 18 inches (NHTSA estimated this 
would increase compliance costs about 8 percent). 

NHTSA was also interested in comments on 
how to improve the conspicuity of platform trail- 
ers, and on the desirability of standardizing to the 
maximum extent possible the treatment of all 
trailers. 

Very few commenters supported a red and 
white alternating combination pattern. ATA, 
Transamerica Leasing, and Robert Crail advocated 
white only; Motor Vehicle Manufacturers 
Association (MVMA) opposed white material on 
the rear as a violation of State laws and a source 
of possible masking of taillamps. Truck Trailer 
Manufacturing Association (TTMA) and United 
Parcel Service (UPS) opposed red on the sides. 
Rudolf Mortimer recommended red on the rear 
and yellow on the sides, while New Jersey sug- 
gested a side treatment of yellow and white. 

The final rule requires only a single stripe of 
material on the side, and not a perimeter oudine. 
Under this circumstance, the agency does not con- 
sider stripes of yellow or white, used alone or 
combined in alternating segments, as sufficiendy 
distinct from common highway lane markings. 
Red and white were the colors used in the 
UMTRl study. NHTSA is confident that the pub- 
lic will quickly learn to associate the red/white 
stripe with trailers, and that the intuitive associa- 



tion of red with danger will reinforce the learning. 
Addressing MVMA's comment on the potential 
masking of stop and turn signal lamps by white ( 
retroreflective material, the rule requires a mini- 
mum spacing of three inches between white mate- 
rial and adjacent red lamps. This is an existing 
requirement of the Motor Carrier Safety Regula- 
tions of the FHWA. Data available to NHTSA 
does not indicate that the presence of red 
retroreflective material adjacent to a red lamp 
affects the perceptibility of the lamp. 

UMTRI found that red and white segments of 
equal length (about 12 inches) were most effec- 
tive in connoting dangers to viewers. The NPRM 
specified a somewhat different design in which 
the red segments were longer (11 to 12 inches) 
than the white (7 to 8 inches); this was based on 
the length of presently available commercial prod- 
ucts. In the final rule, the specification for both 
segments is changed to 12 +/- 6 inches to 
accommodate both the UMTRI study and 
commercially available products, as well as to 
afford flexibility to the trailer manufacturer. 

NHTSA understands that New Jersey presently 
requires retrofit of the sides of 53-foot trailers for 
the rearmost 5 feet in yellow and white material, 
and prohibits red and white material. As noted 
eariier. Standard No. 108 has no retroactive effect 
on trailers in use. However, under the preemption 
clause (15 U.S.C. 1392(d)), the new vehicle 
specifications of Standard No. 108 must be recog- 
nized by the States, and New Jersey will be 
unable to prohibit red and white material on the 
sides of large trailers manufactured on and after 
the effective date of this final rule. NHTSA there- 
fore encourages New Jersey to review its require- 
ment with a view towards allowing red and white 
material for retrofit, and thereby promoting uni- 
formity of conspicuity treatment. 

Reflex Reflectors 
The NPRM proposed that a manufacturer have 
the choice of installing a system of reflex reflec- 
tors instead of retroreflective sheeting. Reflex 
reflectors that conform to SAE Standard J594f 
Reflex Reflectors, January 1977 (the current 
requirement in Standard No. 108), are rated in 
terms of the absolute amount of light reflected in 
proportion to the illumination striking them. The 
size of the reflector and the brightness of the 
material may be balanced to achieve the specified 
amount of reflected light. Retroreflective sheeting. 



PART 571; S 108— PRE-398 



however, is rated in terms of the reflected light 
per unit area, in proportion to the illumination. 
Typically, three reflex reflectors (either white or 
red, and independent of their size and shape) 
would provide the same reflected light as one foot 
of 2-inch D0T-C2 reflective sheeting of the same 
color. The array of reflectors that the agency 
believed equivalent to the proposed alternating 
white/red retroreflective material scheme was a 
group of two white reflectors alternating with a 
group of three red reflectors, the center of each 
reflector in a group being approximately 4 inches 
from the center of the next one in that group. For 
the elements of Alternative 2 that are all white, 
if the reflex reflector performance were as above, 
three white reflectors per foot would likely suf- 
fice. Although these reflectors would be required 
to conform to SAE J594f, they would also be 
required to meet the additional performance 
requirement of providing very high reflectivity 
over a range of entrance angles of light from 30 
degrees left to 30 degrees right. The additional 
requirement ensured that the array of reflex 
reflectors would deliver the same minimum 
performance as the retroreflective sheeting. Reflex 
reflectors molded in bars, resembling the sheeting 
material, but narrower, were an obvious means of 
implementation to NHTSA. For a multiple/retlec- 
tor bar, each segment conforming to SAE J594f 
would be labeled in order to indicate the number 
of reflectors per length of bar. NHTSA requested 
comments on this option, its likely relative 
effectiveness as an alternative to the use of 
retroreflective sheeting, and the likelihood of day- 
time conspicuity enhancement compared with that 
of sheeting. 

Landstar and Wolf Technical Services argued 
that reflectors are more prone to damage than 
sheeting. Advocates claimed that the proposed 
array would be less bright than sheeting, while 
Grote argued exactly the opposite. NHTSA dis- 
agrees with Grote and Advocates. The agency's 
figures show for both sheeting and reflectors a 
value of 3.87 cd/lux per foot of white treatment. 
Grote mistakenly assumed that the values were 
based upon equal areas rather than on equal light 
return. 

NHTSA recognizes that standards and durabil- 
ity differ between sheeting and reflectors, but it 
also recognizes that both products are apparently 
capable of providing the minimum safety 
performance necessary for vehicle conspicuity. 



The final rule allows the option as proposed, with 
a slight modification in the spacing requirement 
to allow arrays a range of alternating color 
lengths analogous to that permitted for sheeting, 
and to eliminate the minimum spacing because 
there is no conesponding maximum brightness for 
sheeting material. Further, as already noted, the 
Federal Highway Administration will conduct a 
separate rulemaking to address concerns about the 
maintenance of the conspicuity treatment required 
by this rulemaking. 

Combination Conspicuity Systems 
Because the retroreflective capabilities of the 
sheeting and reflectors specified by this standard 
are deemed equivalent, there appears to be no 
discernable reason why reflex reflectors meeting 
the new requirements may not be installed in lieu 
of retroreflective sheeting at any required location 
on the side or on the rear, should practicality or 
other conditions so dictate. Allowance of com- 
bination conspicuity systems will afford greater 
flexibility in complying with this rule. 

Certification of Compliance of Retroreflective 
Materials 

The responsibility for compliance with the 
performance requirements of the retroreflective 
sheeting or reflex reflectors used to comply with 
the conspicuity requirements rests upon the manu- 
facturers of the sheeting or reflectors. Thus, 
manufacturers who are providing these materials 
to the trailer manufacturing industry and to 
replacement parts outlets will have to certify 
compliance with Standard No. 108, whether the 
materials are intended for use as original or 
replacement equipment. Such manufacturers must 
also file information in accordance with 49 CFR 
Part 566, Manufacturer Identification, if they 
have not done so before. 

Certification of the retroreflective materials will 
be mandatory. For the retroreflective sheeting, it 
will consist of the characters "D0T-C2," "DOT- 
C3" or "D0T-C4" to distinguish the materials 
from those conforming to Federal Specification 
L-S-300, September 7, 1965, which is presently 
permitted by paragraph. S5. 1.1.4 as an allowable 
alternative for side reflex reflectors. These reflec- 
tors may be marked "DOT" as an indication that 
they meet this earlier version of L-S-300. How- 
ever, it should be noted that they may not meet 
ASTM D 4956-90, nor the conspicuity require- 
ments of the final rule. 



PART 571: S 108— PRE-399 



Each reflex reflector installed for the purpose 
of compliance with the conspicuity requirements 
will also be required to be marked with the letters 
DOT-C as a certification of compliance with the 
conspicuity requirements (reflectors conforming 
only to SAE J594f would continue to be marked 
DOT if then- manufacturer chose that method of 
certification). The spacing of the certification on 
retroreflective materials occasioned some com- 
ment. With respect to strips of all-white material, 
NHTSA proposed to require the DOT-C symbol 
to appear not less than every 12 inches. With 
respect to strips of alternating red and white 
material, the agency proposed that the DOT-C 
symbol appear on each red segment and each 
white segment. However, NHTSA requested com- 
ments on an alternative such as one requiring that 
the DOT-C symbol appear on one color alone, 
with a paragraph added to Standard No. 108 
specifying that such certification shall also be a 
certification of the materials adjacent to it that are 
of a different color. NHTSA requested comments 
on whether individual segment marking would be 
pracficable, or whether other methods may be 
used that have the desired legal result for certifi- 
cafion of materials. In the view of the com- 
menters, the NPRM's alternative suggestion of 
certification once per color cycle appeared to be 
the most reasonable solution. NHTSA is adopting 
this recommendation for materials of alternating 
colors. With respect to the white material used to 
mark the upper rear comers, certificadon will 
appear at least once every 12 inches. 

Possible Elimination of Other Lighting Equipment 
Some commenters believe that existing require- 
ments for lamps and reflectors on large trailers 
should be modified when the conspicuity rule 
becomes effective. UPS suggested eliminating 
clearance lamps. TTMA argued that identification 
lamps and reflectors will no longer be needed. 
The American Petroleum Institute and ATA went 
further, recommending in addition to these, the 
elimination of all marker lamps. On the other 
hand, Grote and Trucklite opposed the elimination 
of any of the present lighting and reflecting 
equipment. 

The agency is opposed to the elimination of 
any lamps, since the conspicuity treatment is 
intended to be a passive augmentation of the 
existing active lighting equipment. Safety depends 
on lamps being present and functioning in poor 



weather conditions, or when the trailer is dirtier 
than normal, conditions that work against the full 
effectiveness of reflected light. f- 

However, rear and side reflex reflectors that are 
mounted at the same height as the conspicuity 
stripes could be considered redundant, even 
though amber side reflectors would be replaced 
with red and white conspicuity treatment. The 
agency is pursuing this matter further through the 
SNPRM that is being prepared for publication. 

Shift to Expression of Measurements in Metric 
System Units 

In implementation of the Department's policy 
to use the metric system where possible in 
rulemakings, the values that were proposed 
conventionally in the NPRM are adopted using 
metric units. For example, the strip of material 
whose width was 2 inches in the NPRM becomes 
one whose width is 50 mm in the final rule. This 
shift will result temporarily in Standard No. 108 
using the conventional system of measurement in 
one section, and the metric system in another. 
However, eventually Standard No. 108 will be 
converted entirely to metric expression, in accord- 
ance with a NHTSA timetable. 

Associated Rulemaking: Rear Underride V 

Protection 
The agency is also seeking to reduce the sever- 
ity of accidents in which vehicles strike the rear 
ends of trailers through rulemaking regarding rear 
underride protection. To the extent that the num- 
ber and severity of rear end crashes would be 
mitigated by enhancing conspicuity, the benefits 
of a rear underride rule might be lessened. 
Interested persons were advised to be aware of 
the relatedness of these two rulemaking actions in 
preparing their comments on each. 

Related Rulemaking: Federal Highway 
Administration 
The FHWA has worked with NHTSA to ensure 
that its standards are compatible with the Federal 
motor vehicle safety standards wherever possible. 
As part of this effort, the FHWA will continue to 
adopt the appropriate sections of NHTSA' s stand- 
ards into the Federal Motor Canier Safety Regu- 
lations (FMCSRs). If amendments to 49 CFR 
Parts 393, Parts and Accessories Necessary for 
Safe OperationTl, and 396. Inspection Repair ^ 
and Maintenance, of the FMCSRs are necessary V_ 
to ensure the continued presence and proper 



PART 571; S 108— PRE-400 



performance of conspicuity enhancements on 
large trailers, the FHWA will address the issue in 
a separate rulemaking. 

This final rule does not have any retroactive 
effect. Under section 103(d) of the National Traf- 
fic and Motor Vehicle Safety Act (15 U.S.C. 
1392(d)), whenever a Federal motor vehicle safety 
standard is in effect, a state may not adopt or 
maintain a safety standard applicable to the same 
aspect of performance which is not identical to 
the Federal standard. Section 105 of the Act (15 
U.S.C. 1394) sets forth a procedure for judicial 
review of final rules establishing, amending or 
revoking Federal motor vehicle safety standards. 
That section does not require submission of a 
petition for reconsideration or other administrative 
proceedings before parties may file suit in court. 

Effective Dote 
Because of the relatively simple efforts that 
would be necessary to comply with the conspicu- 
ity requirements, and the fact that trailers are not 
modified on a model year basis, the agency pro- 
posed an effective date of the final rule that 
would be 12 months after publication of the final 
rule. Accordingly, the effective date of the final 
rule is December 1, 1993. 

Rulemaking Analyses 
Executive Order 12291 (Federal Regulation) 
and DOT Regulatory Policies and Procedures. 
NHTSA has considered the impacts of this rule- 
making action and has determined that although it 
is not major within the meaning of Executive 
Order 12291 "Federal Regulation," it is signifi- 
cant under Department of Transportation regu- 
latory policies and procedures because it involves 
a matter of substantial Congressional and public 
interest. The rulemaking will not have an effect 
upon the economy in excess of $100 million a 
year. NHTSA estimates that the cost to equip all 
new trailers manufactured in a calendar year will 
be $17.3 million. This estimate will not be 
affected by the proportion of manufacturers which 
choose sheeting material versus reflex reflectors 
molded in bars as their means of compliance. The 
agency further estimates that once all trailers 
within the affected categories of trailers comply 
with the new requirements, 2,113 accidents will 
be prevented and 9,052 others will be mitigated 
annually. The resulting reduction in property dam- 
age will be $41.75 million. Thus, the cost of the 
conspicuity system will be offset by the savings 



in property damage alone. However, the expected 
prevention of injuries and fatalities is the reason 
that NHTSA is acting to improve the visibility of 
large trailers. 

NHTSA estimates that the life of the average 
trailer is 14 years. Agency research indicates that 
the original application of conspicuity materials 
can be expected to perform during the entire life 
of the trailer. NHTSA has no studies allowing it 
to quantify a reduction in fatalities and injuries 
that would be expected from use of conspicuity 
material. However, it is reasonable to expect 
prevention of some 80 fatalities and 1,315 injuries 
if they were reduced in proportion to the expected 
reduction in accidents. There is no cost assigned 
to preventing those fatalities and injuries because 
the reduction of property damage alone is 
expected to exceed the cost of conspicuity mate- 
rials and labor. The costs and benefits are cal- 
culated in 1992 dollars. A Regulatory Evaluation 
has been prepared and is available for examina- 
tion by the public in the docket. 

Regulatory Flexibilit}' Act. The agency has also 
considered the effects of this rule in relation to 
the Regulatory Flexibility Act. I certify that this 
rule will not have a significant economic effect 
trailer upon a substantial number of small entities. 
Although trailer manufacturers are generally small 
businesses within the meaning of the Regulatory 
Flexibility Act, the cost impact of complying with 
the regulation will not be significant. The agency 
estimates that compliance costs to the trailer 
buyer will average $102 per trailer to the 
consumer. As for manufacturers of retroreflective 
materials and reflex reflectors, NHTSA notes that 
retroreflective materials that conform to ASTM D 
4956-90 Type V are presently being manufac- 
tured, and that the cost to add DOT certification 
symbols should be only about $.11 a trailer. Fur- 
ther, small organizations and governmental juris- 
dictions will not be significantly affected as the 
price of new trailers equipped with conspicuity 
treatment will not, as already noted above, be 
more than minimally impacted. Accordingly, no 
Regulatory Flexibility Analysis has been prepared. 

Executive Order 12612 {Federalism}. This 
action has been analyzed in accordance with the 
principles and criteria contained in Executive 
Order 12612 on "Federalism." It has been deter- 
mined that the rule does not have sufficient fed- 
eralism implications to warrant the preparation of 
a Federalism Assessment. 



PART 571; S 108— PRE^Ol 



National Environmental Policy Act. NHTSA 
has analyzed this rule for purposes of the 
National Environmental Policy Act. The rule will 
not have a significant effect upon the environ- 
ment. Retroreflective material is non-toxic in 
nature. Further, the rule will not have an effect 
upon fuel consumption. 

Paperwork Reduction Act. The labeling require- 
ments associated with this rule have been submit- 
ted to the Office of Management and Budget for 
approval in accordance with 44 U.S.C. chapter 
35. ADMINISTRATION: National Highway Traf- 
fic Safety Administration; TITLE: Labeling of 
reflective material for trailer conspicuity; NEED 
FOR INFORMATION: Identification of reflective 
material as conforming to requirements; ANTICI- 
PATED USE OF INFORMATION: Routine 
trailer inspection by Federal Highway Administra- 
tion; FREQUENCY; On occasion; BURDEN 
ESTIMATE: 200 hours; RESPONDENTS: 2; 
FORM(S): None; AVERAGE BURDEN HOURS 
PER RESPONDENT: 100; For further informa- 
tion contact: The Information Requirements Divi- 
sion, M-34, Office of the Secretary of Transpor- 
tation, 400 Seventh Street, S.W., Washington, 
D.C. 20590, (202) 366-4735. 

List of Subjects in 49 CFR Part 571 
Imports, Motor vehicle safety. Motor vehicles 
PART 571— FEDERAL MOTOR VEHICLE 
SAFETY STANDARDS. 

In consideration of the foregoing. 49 CFR part 
571 is amended as follows: 

1. The authority citation for part 571 continues 
to read as follows: 

Authority: 15 U.S.C. 1392, 1401, 1403, 1407; 
delegation of authority at 49 CFR 1.50. 
S571.108 [Amended] 

2. Section S3 Application is amended to read: 
S3 Application. This standard applies to: 

(a) Passenger cars, multipurpose passenger 
vehicles, trucks, buses, trailers (except pole trail- 
ers and trailer converter dollies), and motorcycles; 

(b) Retroreflective sheeting and reflex reflec- 
tors manufactured to conform to 85. 7 of this 
standard; and 

(c) Lamps, reflective devices, and associated 
equipment for replacement of like equipment on 
vehicles to which this standard applies. 



3. Sections S5.7, S5.7.I and S5.7.2, S5.7 are 
redesignated S5.8, S5.8.1 and S5.8.2, and a new 
section is added to read: p 

S5.7 Conspicuity Systems. Each trailer of 80 or 
more inches overall width, and with a GVWR 
over 10,000 lbs. manufactured on or after Decem- 
ber 1, 1993, except a trailer designed exclusively 
for living or office use, shall be equipped with 
either retroreflective sheeting that meets the 
requirements of S5.7.1, reflex reflectors that meet 
the requirements of S5.7.2, or a combination of 
retroreflective sheeting and reflex reflectors that 
meet the requirement of S5.7.3. 

S5.7.1 Retroreflective sheeting. Each trailer to 
which S5.7 applies that does not conform to 
S5.7.2 or S5.7.3 shall be equipped with 
retroreflective sheeting that conforms to the 
requirements specified in S5.7.1.1 through 
S5.7.1.5. 

S5.7.1.1 Construction. Retroreflective sheeting 
shall consist of a smooth, flat, transparent exterior 
film with retroreflective elements embedded or 
suspended beneath the film so as to form a non- 
exposed retroreflective optical system. 

S5.7.1.2. Performance requirements. Retro- z_ 
reflective sheeting shall meet the requirements of ' 
ASTM D 4956-90, Standard Specification for 
Retroreflective Sheeting for Traffic Control, for 
Type V Sheeting, except for the photometric 
requirements, and shall meet the minimum photo- 
metric performance requirements specified in Fig- 
ure 29. 

S5.7.1.3 Sheeting pattern, dimensions, and rel- 
ative coefficients of retroreflection. 

(a) Retroreflective sheeting shall be applied in 
a pattern of alternating white and red color seg- 
ments to the side and rear of each trailer, and in 
white to the upper rear corners of each trailer, in 
the locations specified in S5.7.1.4, and illustrated 
in Figure 30. 

(b) Except for a segment that is trimmed to 
clear obstnictions, or lengthened to provide red 
sheeting near red lamps, each white or red seg- 
ment shall have a length of 300mm +1- 150 mm. 

(c) Neither white nor red sheeting shall rep- 
resent more than two thirds of the aggregate of 
any continuous strip marking the width of a 
trailer, or any continuous or broken strip marking ~ 
its length. 



PART 571; S I( 



(d) Retroreflective sheeting shall have a width 
of 50 mm (Grade DOT-C2). 75 mm (Grade DOT- 
A C3), or 100 mm (Grade D0T-C4). 
^^ (e) The coefficients for retroreflection of each 

segment of red or white sheeting shall be not less 
than the minimum values specified in Figure 29 
of diis standard for grades D0T-C2, D0T-C3, 
and D0T-C4. 

S5.7.1.4 Location, (a) Retroreflective sheeting 
shall be applied to each trailer on the side and 
rear as specified below, but need not be applied 
to discontinuous surfaces such as outside ribs, 
stake post pickets on platform trailers, and exter- 
nal protruding beams, or to items of equipment 
such as door hinges and lamp bodies. 

(b) The edge of white sheeting shall be not be 
located closer than 75 mm to the edge of the 
luminous lens area of any lamp that is required 
by this standard. 

(c) The edge of red sheeting shall not be 
located closer than 75 mm to the edge of the 
luminous lens area of any lamp that is required 
by this standard. 

55. 7. 1.4.1 Rear. Retroreflective sheeting shall 

• be applied to the rear of each trailer as follows: 
(a) Element 1: a horizontal strip of sheeting in 
alternating colors across the full width of the 
trailer as close to the extreme edges as prac- 
ticable, and as close as practicable to 1.25 meters 
above the road surface. 

(b) Element 2: two pairs of white strips of 
sheeting, each pair consisting of strips 300 mm 
long of grade D0T-C2 (50 mm wide), D0T-C3 
(75 mm wide), or D0T-C4 (100 mm wide), 
applied horizontally and vertically to the right and 
left upper contours of the body, as viewed from 
the rear, as close to the top of the trailer and as 
far apart as practicable. 

(c) Element 3; a strip of sheeting in alternating 
colors across the full width of the horizontal 
member of the rear underride protection device. 

55.7. 1.4.2 Side. Retroreflective sheeting shall 
be applied to each side of a trailer as follows: 

(a) A horizontal strip of sheeting in alternating 
colors, originating and terminating as close to the 
front and rear ends as practicable, and as close as 
practicable to 1.25 m above the road surface 
except that, at the location chosen, the strip shall 
^ not be obscured in whole or in part by other 

W motor vehicle equipment or trailer cargo. The 

strip need not be continuous as long as not less 



than half of the length of the trailer is covered 
and the spaces are distributed as evenly as prac- 
ticable. 

(b) If necessary to clear rivet heads or other 
similar obstructions, grade DOT-C2 retroreflective 
sheeting may be separated into two 25 mm wide 
strips of the same length and color, separated by 
a space of not more than 25 mm, and used in 
place of the retroreflective sheeting that would 
otherwise be applied. 

S5.7.1.5 Certification. The letters DOT-C2, 
D0T-C3, or D0T-C4, as appropriate, constituting 
a certification that the retroreflective sheeting 
conforms to the requirements of S5.7.1.2, shall 
appear at least once on the exposed surface of 
each white or red segment of retroreflective sheet- 
ing, and at least once every 300 mm on 
retroreflective sheeting that is white only. The 
characters shall be not less than 3 mm high, and 
shall be permanently stamped, etched, molded, or 
printed in indelible ink. 

S5.7.2 Reflex Reflectors. Each trailer to which 
S5.7 applies that does not conform to S5.7.1 or 
S5.7.3 shall be equipped with reflex reflectors in 
accordance with this section. 

S5. 7. 2. 1(a) Each reflex reflector shall conform 
to SAE Standard J594f, Reflex Reflectors, January 
1977. 

(b) Each red reflex reflector shall also provide, 
at an observation angle of 0.2 degree, not less 
than 310 millicandelas/lux at any light entrance 
angle between 30 degrees left and 30 degrees 
right, including an entrance angle of degree. 

(c) Each white reflex reflector shall also pro- 
vide, at an observation angle of 0.2 degree, not 
less than 1290 millicandelas/lux at any light 
entrance angle between 30 degrees left and 30 
degrees right, including an entrance angle of 
degree. 

S5. 7.2.2 Reflex reflectors shall be installed and 
located as specified below: 

(a) In the same locations and in the same 
length in which retroreflective sheeting is required 
by S5.7.1.4 to be applied in alternating colors, 
reflex reflectors shall be installed in a repetitive 
pattern of two or three white reflex reflectors 
alternating with two or three red reflex reflectors, 
with the center of each reflectror more than 100 
mm from the center of each adjacent reflector. 

(b) In the same locations and in the same 
length in which white retroreflective sheeting is 



PART 571; S 



-PRE^03 



required by S5.7.1.4 to be installed, white reflex 
reflectors shall be installed, with the center of 
each white reflex reflector not more than 100 mm 
the center of each adjacent reflector. 

S5.7.2.3 Certification. The exposed surface of 
each reflexreflector shall be marked with the let- 
ters DOT-C which constitutes a certification that 
the reflector conforms to all applicable require- 
ments of section 571.108 of this part. The certifi- 
cation shall be not less than 3 mm high, and 
permanently stamped, etched, molded or printed 
in indelible ink. 

S5.7.3 Combination of sheeting and reflectors. 
Each trailer to which S5.7 applies that does not 
conform to S5.7.1 or S5.7.2, shall be equipped 
with retroreflective materials that meet the 
requirements of S5.7.1 except that reflex reflec- 
tors that meet the requirements of S5.7.2.1, and 
that are installed in accordance with S5.7.2.2, 
may be used instead of any corresponding ele- 
ment of retroreflective sheeting located as 
required by S5.7.1.4. 

4. Table I is amended by adding the following 
at the end thereof: 



Multipurpose pas- Trailers Applicable 

Sanger vehicles, SAE 

trucks, and buses standards 



5. Table II is amended by adding the following 
after the requirements for "Intermediate side _ 
reflex reflectors": ^ 



Item Multipurpose pas- Trailers 

senger vehicles, 
trucks, and buses 

Conspicuity See S5.7 See S5.7 

6. Figure 29 is added as follows: 

OBSERVATION ANGLE 



Height above 
road sur- 
face 



Entrance Angle 


0.2 Degree 
White Red 


0.5 Deg 


ree 


Grade 


White 


Red 


-4 degrees 
30 degrees 


250 
250 


60 
60 


65 
65 


10 
10 


DOT-C2 
DOT-C2 


-4 degrees 
30 degrees 


165 
165 


40 
40 


43 
43 


10 
10 


DOT-C3 
DOT-C3 


-4 degrees 
30 degrees 


125 
125 


30 
30 


33 
33 


8 


DOT-C4 
DOT-C4 



Conspicuity 



Figure 29 Minimum Photometeric Performance 

of Retroreflective Sheeting (Canadela/Lux/ 

Square IVIeter) 

7. Figure 30 is added as follows: 
Issued on: December 3, 1992. 

Marion C. Blakey 
Administrator 

57 F.R. 58406 
December 10, 1992 




VAN PLATFORM 

Figure 30 Typical Trailer Conspicuity Treatments 



c 



PART 571; S 108— PRE-404 



MOTOR VEHICLE SAFETY STANDARD NO. 108 

Lamps, Reflective Devices, and Associated Equipment-Passenger Cars, 

Multipurpose Passenger Vehicles, Trucks, Buses, Trailers, and Motorcycles 

(Docket No. 69-18) 



51 Scope. This standard specifies requirements 
for original and replacement lamps, reflective 
devices, and associated equipment. 

52 Purpose. The purpose of this standard is to 
reduce traffic accidents and deaths and injuries 
resulting from traffic accidents, by providing ade- 
quate illumination of the roadway, and by enhanc- 
ing the conspicuity of motor vehicles on the public 
roads so that their presence is perceived and their 
signals understood, both in daylight and in dark- 
ness or other conditions of reduced visibility. 

53 Application. [This standard applies to: 

(a) Passenger cars, multipurpose passenger 

vehicles, trucks, buses, trailers (except pole trail- 
^ ers and trailer converter dollies), and motorcycles; 
^ (b) Retroreflective sheeting and reflex reflectors 

manufactured to conform to S5.7 of this standard; 

and 

(c) Lamps, reflective devices, and associated 

equipment for replacement of like equipment on 

vehicles to which this standard applies. (57 F.R. 

58406— December 10, 1992. Effective: December 1, 

1993)] 

54 Definitions. "Aiming Reference Plane" 
means a plane which is perpendicular to the 
longitudinal axis of the vehicle and tangent to the 
forwardmost aiming pad on the headlamp. 

Beam contributor means an indivisible optical 
assembly including and lens, reflector, and light 
source, that is part of an integral beam 
headlighting system and contributes only a por- 
tion of a headlamp beam. 

Cargo lamp is a lamp that is mounted on a 
multipurpose passenger vehicle, truck, or bus for 
the purpose of providing illumination to load or 
unload cargo. 

Direct reading indicator means a device that is 
m mounted in its entirety on a headlamp or 

W headlamp aiming or headlamp mounting equip- 



ment, is part of a VHAD, and provides informa- 
tion about headlamp aim in an analog or digital 
fonnat. 

Effective projected luminous lens area means 
that area of the projection on a plane perpendicu- 
lar to the lamp axis of the portion of the light- 
emitting surface that directs light to the photo- 
metric test pattern, and does not include mounting 
hole bosses, reflex reflector area, beads or rims 
that may glow or produce small areas of 
increased intensity as a result of uncontrolled 
light from smallareas {V2 deg. radius around the 
test point). 

Flash means a cycle of activation and deactiva- 
tion of a lamp by automatic means, continuing 
until stopped either automatically or manually. 

Headlamp test fixture means a device designed 
to support a headlamp or headlamp assembly in 
the test position specified in the laboratory tests 
and whose mounting hardware and components 
are those necessary to operate the headlamp as 
installed in a motor vehicle. 

Integral Beam Headlamp means a headlamp 
comprising an integral and indivisible optical 
assembly including lens, reflector, and light 
source, that is neither a standardized sealed beam 
headlamp designed to conform to paragraph S7.3 
nor a replaceable bulb headlamp designed to con- 
form to paragraph S7.5. 

Multiple compartment lamp means a device 
which gives its indication by two or more sepa- 
rately lighted areas which are joined by one or 
more common parts, such as a housing or lens. 

Multiple lamp arrangement means an array of 
two or more separate lamps on each side of the 
vehicle which operate together to give a signal. 

Remote reading indicator means a device that 
is not mounted in its entirety on a headlamp or 
headlamp aiming or headlamp mounting equip- 
ment, but otherwise meets the definition of a 
direct reading indicator. 



PART 571; S 



(Rev. 12/10/92) 



Replaceable bulb headlamp means a headlamp 
comprising a bonded lens and reflector assembly 
and one or two standardized replaceable light 
sources. 

Seasoning means a process of energizing the 
filament of a headlamp, at design voltage, for a 
period of time equal to 1 percent of average rated 
laboratory life. 

Standardized replaceable light source means an 
assembly of a capsule, base, and terminals, that 
meets the requirements of S7.6. 

Vehicle headlamp aiming device or VHAD 
means motor vehicle equipment permanently 
installed on a motor vehicle by the manufacturer 
of the vehicle, which is used for determining the 
horizontal and vertical aim of headlamps. 

S5 Requirements. 

S5.1 Required motor veliicle lighting equip- 
ment. 

S5.1.1 Except as provided in succeeding para- 
graphs of S5.1.1, each vehicle shall be equipped 
with at least the number of lamps, reflective 
devices, and associated equipment specified in 
Tables I and III and S7, as applicable. Required 
equipiTient shall be designed to conform to the 
SAE Standards or Recommended Practices ref- 
erenced in those tables. Table I applies to multi- 
purpose passenger vehicles, trucks, trailers, and 
buses, 80 or more inches in overall width. Table 
III applies to passenger cars and motorcycles and 
to multipuipose passenger vehicles trucks, trailers, 
and buses, less than 80 inches in overall width. 

55.1.1.1 A truck tractor need not be equipped with 
turn-signal lamps mounted on the rear if the turn 
signal lamps at or near the front are so constructed 
(double-faced) and so located that they meet the 
requirements for double-faced turn signals speci- 
fied in SAE Standard J588e, Turn Signal Lamps, 
September 1970. 

55.1.1.2 A truck tractor need not be equipped with 
any rear side marker devices, rear clearance 
lamps, and rear identification lamps. 

55.1.1.3 Intermediate side marker devices are not 
required on vehicle less than 30 feet in overall 
length. 



55.1 .1 .4 Reflective material conforming to Federal 
Specification L-S-300, Sheeting and Tape, Reflec- 
tive: Non-exposed Lens, Adhesive Backing, f- 
September 7, 1965, may be used for side reflex 
reflectors if this material, as used on the vehicle, 
meets the performance standards in either Table I 

or Table lA of SAE Standard J594f, Reflex Reflec- 
tors, January 1977. 

55.1.1.5 The turn signal operating unit on each 
passenger car and multipurpose passenger vehicle, 
truck, and bus less than 80 inches in overall width 
shall be self-canceling by steering wheel rotation 
and capable of cancellation by a manually oper- 
ated control. 

55.1.1.6 [(a)] Each stop lamp manufactured to 
replace a stop lamp that was designed to conform 
to SAE Standard J586b Stop Lamps, June 1966, 
may also be designed to conform to J586b. It shall 
meet the photometric minimum candlepower 
requirements for Class A red turn signal lamps 
specified in SAE Standard J575d, Tests for Motor 
Vehicle Lighting Devices and Components, August 
1967. Each such lamp manufactured for use on a 
passenger car and on a multipurpose passenger 
vehicle, truck, trailer, or bus less than 80 inches ^ 
in overall width shall have an effective projected 
luminous area not less than 3'/2 square inches. If 
multiple compartment lamps or multiple lamps are 
used, the effective projected luminous area of each 
compartment or lamp shall be not less than 3'/2 
square inches; however, the photometric require- 
ments may be met by a combination of compart- 
ments or lamps. 

[(b) Each stop lamp manufactured to replace a 
stop lamp that was designed to conform to SAE 
Standard J586c, Stop Lamps, August 1970, may 
also be designed to conform to J586c. (55 F.R. 
20158— May 15, 1990. Effective: December 1, 
1990.)] 

[(c) A multipuipose passenger vehicle, truck, 
bus, or trailer whose overall width is 80 inches or 
more, manufactured on or before November 30, 
1991, and whose stop lamps are located more 
than 22 inches apart, may be equipped with stop 
lamps designed to conform to SAE Standard 
J586c, Stop Lamps, August 1970." (55 F.R. 
20158— May 15, 1990. Effective: December 1, 
1990.)] 

55.1.1.7 (a) Each turn signal lamp manufactured V 
to replace a turn signal lamp that was designed to 



(Rev. 5/15/90) 



PART 571; S 108-2 



conform to SAE Standard J588d Turn Signal 
Lamps. June 1966, may also be designed to con- 
forni to J588d, and shall meet the photometric 
minimum candlepower requirements for Class A 
turn signal lamps specified in SAE Standard 
J575d, Tests for Motor Vehicle Lighting Devices 
and Components, August 1967. Each such lamp 
manufactured for use on a passenger car and on 
a multipurpose passenger vehicle, truck, trailer or 
bus less than 80 inches in overall width shall have 
an effective projected luminous area not less than 
3V2 square inches. If multiple compartment lamps 
or multiple lamps are used, the effective projected 
luminous area of each compartment or lamp shall 
be not less than 3'/2 square inches; however, the 
photometric requirements may be met by a com- 
bination of compartments or lamps. Each such 
lamp manufactured for use on a multipurpose pas- 
senger vehicle, truck, trailer or bus 80 inches or 
more in overall width shall have an effective pro- 
jected luminous area not less than 12 square 
inches. 

[(b) Each turn signal lamp manufactured to 
replace a turn signal lamp that was designed to 
conform to SAE Standard J588e, Turn Signal 
Lamps. September 1970, may also be designed to 
conform to SAE Standard J588e. Note 6 of Table 
1 of SAE Standard J588e does not apply. A stop 
lamp that is not optically combined with a turn 
signal lamp shall remain activated when the turn 
signal is flashing. (55 F.R. 20158— May 15, 1990. 
Effective: December 1, 1990.)] 

[(c) A multipurpose passenger vehicle, truck, 
bus, or trailer, whose overall width is 80 inches 
or greater, manufactured on or before November 
30, 1991, and whose turn signal lamps are located 
more than 22 inches apart, may be equipped with 
turn signal lamps designed to conform to SAE 
Standard J588e, Turn Signal Lamps. September 
1970. (55 F.R. 20158-May 15, 1990. Effective: 
December 1, 1990.)] 

S5.1.1.8 For each motor vehicle less than 30 feet 
in overall length, the photometric-minimum 
candlepower requirements for side marker lamps 
specified in SAE Standard J592e, Clearance, Side 
Marker, and Identificatiou Lamps. July 1 972, may 
be met for all inboard test points at a distance of 



15 feet from the vehicle and on a vertical plane 
that is perpendicular to the longitudinal axis of the 
vehicle and located midway between the front and 
rear side marker lamps. 

55.1.1.9 A boat trailer whose overall width is 80 
inches or more need not be equipped with both 
front and rear clearance lamps provided an amber 
(to front) and red (to rear) clearance lamp is 
located at or near the midpoint on each side so as 
to indicate its extreme width. 

55.1.1.10 Multiple license plate lamps and backup 
lamps may be used to fulfill the requirements of 
the SAE Standards applicable to such lamps ref- 
erenced in Tables I and III. 

55.1.1.11 [A parking lamp, tail lamp, stop lamp 
manufactured to replace a stop lamp designed to 
conform to SAE Standard J586c. Stop Lamps, 
August 1970, or turn signal lamp manufactured to 
replace a turn signal lamp that was designed to 
conform to SAE Standard J588e, Turn Signal 
Lamps. September 1970, shall meet the minium 
percentage specified in Figure la of the cor- 
responding minimum allowable value specified in 
Table 1 and Table 3 of SAE J588 NOV 84 Turn 
Signal Lamps except that motorcycle turn signal 
lamps need meet only one-half of the minimum 
photometric values specified in Figure lb. (55 F.R. 
20158— May 15, 1990. Effective: December 1, 
1990.)] 

Figure 1 a. — Required percentages of minimum 
candlepower of Figure lb. 



(iteg) 




Turn 
signal 


Srop 


Park- 
inf> 


Tail 




5L. 5R 


20 


20 


20 












20L. 20R 


12.5 


12.5 


10 


15 


5U. 5D 


lOL, lOR 


37.5 


37.5 


20 


40 




V 


87.5 


87.5 


70 


90 




lOL, lOR 


50 


50 


35 


40 


H 


5L, 5R 


100 


100 


90 


100 




V 


100 


100 


100 


100 



Note. — Minimum design candlepower requirements are 
determined by multiplying the percentages given in this Figure by 
the minimum allowable candlepower values in Figure lb. The 
resulting values shall be truncated after one digit to the right of the 
decimal point. 



PART 571; S 1( 



(Rev. 5/15/90) 



Figure lb. — Minimum and maximum allow- 
able candlepower values. 

Lighted Sections 

Lamp 

/ 2 9 

Stop 80/300 95/360 110/420 

Tail' 2/18 3.5/20 5.0/25 

Parking^ 4.0/125 

Red turn signal 80/300 95/360 110/420 

Yellow turn signal rear 130/750 150/900 175/1050 

Yellow turn signal front 200/- 240/- 275/- 

Yellow turn signal front ' 500/- 600/- 685/- 

' Maximum at H or above. 

-The maximum candlepower value of 125 applies to all test 
points at H or above. The maximum allowable candlepower value 
below H is 250. 

-'Values apply when the optical axis (filament center) of the front- 
turn signal is at a .spacing less than 4 inches (10 cm.) from the 
lighted edge of the headlamp unit providing the lower beam, or from 
the lighted edge of any additional lamp installed as original 
equipment and which supplements the lower beam. 

S5.1.1.12 [A parking lamp, tail lamp, stop lamp 
manufactured to replace a stop lamp designed to 
conform to SAE Standard J586c Stop Lamps, 
August 1970, or turn signal lamp manufactured to 
replace a turn signal lamp designated to conform 
to the SAE Standard J588e, Turn Signal Lamps, 
September 1970, is not required to meet the mini- 
mum photometric value at each test point speci- 
fied in this standard if the sum of the percentages 
of the minimum candlepower measured at the test 
points is not less than that specified for each 
group listed in Figure Ic. (55 F.R. 20158— May 15, 
1990. Effective: December 1, 1990.)] 

Figure Ic. — Sum of the percentages of 
grouped minimum candlepower. 

Croups and test points J"™^ Slop ''"^'^' Tail 

10U-5L, 5U-20L, 5D-20L, lOD- 

5L 65 65 60 70 

5U-10L. H-IOL, 5D-10L 125 125 75 120 

H-5L, 5U-V, NV, 5D-V, H-5R . 475 475 420 480 

5U-10R, H-IOR, 5D-10R 125 125 75 120 

10U-5R, 5U-20R, 5D-20R, 

lOD-SR 65 65 60 70 



55.1.1.13 Each passenger car, and each multipur- 
pose passenger vehicle, tiuck, and bus of less than 
80 inches overall width, shall be equipped with a 
turn signal operating unit designed to complete a 
durability test of 100,000 cycles. 

55.1.1.14 A trailer that is less than 30 inches in 
overall width may be equipped with only one tail 
lamp, stop lamp, and rear reflex reflector, which 
shall be located at or near its vertical centerline. 



55.1.1.15 A trailer that is less than 6 feet in over- 
all length, including the tongue, need not be 
equipped with front side marker lamps and front 
side reflex reflectors. ' 

55.1.1.16 A lamp designed to use a type of bulb 
that has not been assigned a mean spherical 
candlepower rating by its manufacturer and is not 
listed in SAE Standard J 573d, Lamp Bulbs and 
Sealed Units, December 1986, shall meet the 
applicable requirements of this standard when 
used with any bulb of the type specified by the 
lamp manufacturer, operated at the bulb's design 
voltage. A lamp that contains a sealed-in bulb 
shall meet these requirements with the bulb oper- 
ated at the bulb's design voltage. 

55.1.1.17 Except for a lamp having a sealed-in 
bulb, a lamp shall meet the applicable require- 
ments of this standard when tested with a bulb 
whose filament is positioned within ± .010 inch of 
the nominal design position specified in SAE 
Standard J573d, Lamp Bulbs and Sealed Units, 
December 1968, or specified by the bulb manufac- 
turer. 

55.1.1.18 A backup lamp is not required to meet 
the minimum photometric values at each test point 
specified in Table I of SAE Standard J593c, 
Backup Lamps, February 1968 if the sum of the 
candlepower measured at the test points within 
each group listed in Figure 2 is not less than the 
group totals specified in that figure. 

(a) Each headlamp system, other than a 
headlamp system designed to conform to para- 
graph S7.5, that is designed to use such external 
aiming devices shall not deviate more than 0.30 
degree when a downward torque of 201b.-in. (2.25 
N-m) is applied to the headlamp in its normal 
operating position, through the lamp's mechanical 
axis at the plane of the forwardmost aiming pad. 
Each headlamp system that is designed to con- 
form to paragraph S7.5 and that is designed to 
use such external aiming devices, and which is 
manufactured on or after September 1, 1990, shall 
comply with this paragraph. 

55.1.1.19 Each variable load turn signal flasher 
shall comply with voltage drop and durability 
requirements of SAE Standard J590b, Turn Signal 
Flasher, October 1965 with the maximum design 
load connected, and shall comply with starting 
time, flash rate, and percent current "on" time 



(Rev. 5/15/90) 



PART 571; S 108-4 



requirements of J590b both with the minimum and 
with the maximum design load connected. 

55.1.1.20 The lowest voltage drop for turn signal 
flashers and hazard warning signal flashers meas- 
ured between the input and load terminals shall 
not exceed 0.8 voU. 

55.1.1.21 A motor-driven cycle whose speed 
attainable in 1 mile is 30 mph or less need not be 
equipped with turn signal lamps. 

55.1.1.22 A motor-driven cycle whose speed 
attainable in 1 mile is 30 mph or less may be 
equipped with a stop lamp whose effective pro- 
jected luminous lens area is not less than 3'/2 
square inches and whose photometric output for 
the groups of test points specified in Figure 1 is 
at least one-half of the minimum values set forth 
in that figure. 

55.1.1.23 Each tail lamp manufactured to replace 
the tail lamp designed to conform to SAE Stand- 
ard J585d, Tail Lamps, August 1970, may also be 
designed to conform to J585d. 

55.1.1.24 Each turn signal lamp manufactured to 
replace a turn signal lamp (on a motorcycle) that 
was designed to conform to SAE Standard J588d, 
Turn Signal Lamps, June 1966, may also be 
designed to conform to J588d. 

55.1.1.25 Each turn signal lamp on a motorcycle 
manufactured on and after January 1, 1973, shall 
have an effective projected luminous area of not 
less than V/i square inches. 

55.1.1.26 Note 6 of Table 1 in SAE Standard 
J588e, Tiini Signal Lamps, September 1970. does 
not apply. [A stop lamp that is not optically com- 
bined, as defined by SAE Information Report J387 
Terminology — Motor Vehicle Lighting NOV 87, 
with a turn signal lamp shall remain activated 
when the turn signal is flashing. (56 F.R. 26343 — 
June 7, 1991. Effective: July 8, 1991.)] 

55.1.1.27 (a) Except as provided in paragraph (b) 
of this section, each passenger car manufactured 
on or after September 1, 1985, and each multipur- 
pose passenger vehicle, truck, and bus whose 
overall width is less than 80 inches, whose 
GVWR is 10,000 pounds or less, manufactured on 



or after September 1, 1993, shall be equipped with 
a high-mounted stop lamp which: 

(1) Shall have an effective projected lumi- 
nous area not less than AV2 square inches. 

(2) Shall have a signal visible to the rear 
through a horizontal angle from 45 degrees to the 
left to 45 degrees to the right of the longitudinal 
axis of the vehicle. 

(3) Shall have the minimum photometric val- 
ues in the amount and location listed in Figure 
10. 

(4) Need not meet the requirements of para- 
graphs 3.1.6 Moisture Test, 3.1.7 Dust Test, and 
3.1.8 Corrosion Test of SAE Recommended Prac- 
tice J 186a if it is mounted inside the vehicle. 

(5) Shall provide access for convenient 
replacement of the bulb without the use of special 
tools. 

(b) Each multipurpose passenger vehicle, truck 
and bus whose overall width is less than 80 
inches, whose GVWR is 10,000 pounds or less, 
whose vertical centerline, when the vehicle is 
viewed from the rear, is not located on a fixed 
body panel but separates one or two movable 
body sections, such as doors, which lacks suffi- 
cient space to install a single high-mounted stop 
lamp on the centerline above such body sections, 
and which is manufactured on or after September 
1, 1993, shall have two high-mounted stop lamps 
which: 

(1) Are identical in size and shape and have 
an effective projected luminous area not less than 
2 '74 inches each. 

(2) Together have a signal to the rear visible 
as specified in paragraph (a)(2) of this section. 

(3) Together have the minimum photometric 
values specified in paragraph (a)(3) of this sec- 
tion. 

(4) Shall provide access for convenient 
replacement of the bulbs without special tools. 

[S5.1.1.28 A multipurpose passenger vehicle, 
truck, or bus, whose overall width is less than 80 
inches, and whose GVWR is 10,000 pounds or 
less, that is manufactured between September 1, 
1992 and September 1, 1993, may be equipped 
with a high-mounted stop lamp or, in the case of 
vehicles subject to S5. 1.1. 27(b), two high-mounted 
stop lamps, that conform to S5.1.1.27 and 
S5.3.1.8. (56 F.R. 16015— April 19, 1991. Effective: 
Optional compliance, September 1, 1992; Manda- 
tory compliance, September 1, 1993)J 



PART 571: S 108-5 



(Rev. 6/7/91) 



55.1.1.29 Instead of the headlamps specified by 
Table III, a motorcycle may be equipped with one 
half of any headlighting system specified in S7 
which provides both a full upper beam and full 
lower beam, and where more than one lamp must 
be used, the lamps shall be mounted vertically, 
with the lower beam as high as practicable. When 
installed on a motorcycle such half system need 
not meet the aiming requirements specified in S7. 

55.1.1.30 Each replaceable bulb headlamp that is 
designed to meet the photometric requirements of 
SAE Recommended Practice J584, Motorcycle 
Headlamps, April 1964, and that is equipped with 
a light source other than a standardized replace- 
able light source, and that is manufactured on or 
after September 1, 1990 shall have the word 
"motorcycle" permanently marked on the lens in 
characters not less than 0.114 inch (3mm) in 
height. 

55.1 .1 .31 On a motor vehicle whose overall width 
is less than 80 inches: 

(a) The functional lighted lens area of a single 
compartment stop lamp, and a single compartment 
rear turn signal lamp, shall be not less than 50 
square centimeters. 

(b) If a multiple compartment lamp or multiple 
lamps are used to meet the photometric require- 
ments for stop lamps and rear turn signal lamps, 
the functional lighted lens area of each compart- 
ment or lamp shall be at least 22 square centi- 
meters, provided the combined area is at least 50 
square centimeters. 

55.1.1.32 On a motor vehicle, except a passenger 
car, whose overall width is 80 inches or more, 
measurements of the functional lighted lens area, 
and of the photometries, of a multiple compart- 
ment stop lamp, and a multiple compartment turn 
signal lamp, shall be made for the entire lamp and 
not for the individual compartments. 

S5.1.2 Plastic materials used for optical parts such 
as lenses and reflectors shall conform to SAE Rec- 
ommended Practice J576c, May 1970, except that: 

(a) Plastic lenses used for inner lenses or those 
covered by another material and not exposed 
directly to sunlight shall meet the requirements of 
paragraphs 3.4 and 4.2 of SAE J576c. when cov- 
ered by the outer lens or other material; 

(b) After the outdoor-exposure test, the haze 
and loss of surface luster of plastic materials used 



for lamp lenses shall not be greater than 30 per- 
cent haze as measured by ASTM- 1 003-6 1 , Haze ^ 
cmd Luminous Transmittance of Transparent Plas- ( 
tic; and 

(c) After the outdoor exposure test, plastic 
materials used for reflex reflectors shall meet the 
appearance requirements of paragraph 4.2.2 of 
SAE J576c. 

55.1.3 No additional lamp, reflective device, or 
other motor vehicle equipment shall be installed 
that impairs the effectiveness of lighting equip- 
ment required by this standard. 

55.1.4 Each school bus shall be equipped with a 
system of either: 

(a) Four red signal lamps designed to conform 
to SAE Standard J887, School Bus Red Signal 
Lamps, July 1964, and installed in accordance 
with that standard; or 

(b) Four red signal lamps designed to conform 
to SAE Standard J887, School Bus Red Signal 
Lamps, July 1964, and four amber signal lamps 
designed to conform to that standard, except for 
their color, and except that their candlepower 
shall be at least 2'/2 times that specified for red "^ 
signal lamps. Both red and amber lamps shall be 
installed in accordance with SAE Standard J887, 
except that: 

(i) Each amber signal lamp shall be located 
near each red signal lamp, at the same level, but 
closer to the vertical centerline of the bus; and 

(ii) The system shall be wired so that the 
amber signal lamps are activated only by manual 
or foot operation, and if activated, are automati- 
cally deactivated and the red signal lamps auto- 
matically activated when the bus entrance door is 
opened. 

55.1.5 The color in all lamps, reflective devices, 
and associated equipment to which this standard 
applies shall comply with SAE Standard J578c, 
Color Specification for Electric Signal Lighting 
Devices, February 1977. 

S5.2. Other requirements. 

S5.2.1 The words "it is recommended that," 
"recommendations," or "should be" appearing in 
any SAE Standard or Recommended Practice ref- f^ 
erenced or subreferenced in this standard shall be ^ 
read as setting forth mandatory requirements. 



(Rev. 7/19/89) 



PARI' 571; S 108-6 



except that the aiming pads on the lens face and 
the blacl: area surrounding the signal lamp, rec- 
ommended in SAE Standard J887, School Bus Red 
Signal Lamps, July 1964, are not required. 

S5.2.2 The words "Type 1 (SW)," 'Type 2 
(53/4")," "Type 2 (7")," "Type lA," "Type 
2A," and "Type 2B" appearing in any SAE 
Standard or Recommended Practice referenced or 
subreferenced in this standard shall also be read as 
setting forth requirements respectively for the fol- 
lowing types of headlamps: ICl, 2C1, 2D1, lAl, 
2A1, and2BI. 

S5.3 Location of required equipment. 

5.3.1 Except as provided in succeeding paragraphs 
of S5.3.1 [and S7] each lamp, reflective device, 
and item of associated equipment shall be securely 
mounted on a rigid part of the vehicle other than 
glazing that is not designed to be removed except 
for repair, in accordance with the requirements of 
Tables I or III [as applicable, and S7, and in the 
location] specified in Table II (multipurpose pas- 
senger vehicles, trucks, trailers, and buses 80 or 
more inches in overall width) and Table IV (all 
passenger cars, and motorcycles, and multipurpose 
passenger vehicles, trucks, trailers, and buses less 
than 80 inches in overall width), as applicable. (54 
F.R. 30223— July 19, 1989. Effective: July 19, 1989.) 

S5.3.1.1 Except as provided in S5. 3. I.I.I, each 
lamp and reflective device shall be located so that 
it meets the visibility requirements specified in 
any applicable SAE Standard or Recommended 
Practice. In addition, no part of the vehicle shall 
prevent a parking lamp, taillamp, stop lamp, turn- 
signal lamp, or backup lamp from meeting its 
photometric output at any applicable group of test 
points specified in Figures Ic and 2, or prevent 
any other lamp from meeting the photometric out- 
put at any test point specified in any applicable 
SAE Standard or Recommended Practice. How- 
ever, if motor vehicle equipment (e.g., mirrors, 
snow plows, wrecker booms, backhoes, and 
winches) prevents compliance with this paragraph 
by any required lamp or reflective devices, an 
auxiliary lamp or device meeting the requirements 
of this paragraph shall be provided. 

S5.3.1.1.1 Clearance lamps may be mounted at a 
location other than on the front and rear if nec- 
essary to indicate the overall width of a vehicle. 



or for protection from damage during normal 
operation of the vehicle, and at such a location 
they need not be visible at 45 degrees inboard. 

55.3.1.2 On a truck tractor, the red rear reflex 
reflectors may be mounted on the back of the cab, 
at a minimum height not less than 4 inches above 
the height of the rear tires. 

55.3.1.3 On a trailer, the amber front side reflex 
reflectors and amber front side-marker lamps may 
be located as far forward as practicable exclusive 
of the trailer tongue. 

55.3.1.4 When the rear identification lamps are 
mounted at the extreme height of a vehicle, rear 
clearance lamps need not meet the requirement of 
Table II that they be located as close as prac- 
ticable to the top of the vehicle. 

55.3.1.5 The center of the lens referred to in SAE 
Standard J593c. Backup Lamps, February 1968, is 
the optical center. 

55.3.1.6 On a truck tractor, clearance lamps 
mounted on the cab may be located to indicate the 
width of the cab, rather than the overall width of 
the vehicle. 

55.3.1.7 On a motor vehicle on which the front 
turn signal lamp is less than 100 mm from the 
lighted edge of a lower beam headlamp, as meas- 
ured from the optical center of the turn signal 
lamp, the multiplier applied to obtain the required 
minimum luminous intensities shall be 2.5. 

55.3.1.8 [(a) Each high-mounted stop lamp 
installed in or on a vehicle subject to S5. 1.1. 27(a) 
shall be located as follows: 

(1) With its center at any place on the verti- 
cal centerline of the vehicle, including the glaz- 
ing, as the vehicle is viewed from the rear. 

(2) If the lamp is mounted below the rear 
window, no portion of the lens shall be lower 
than 6 inches below the rear window on 
convertibles, or 3 inches on other passenger cars. 

(3) If the lamp is mounted inside the vehicle, 
means shall be provided to minimize reflections 
from the light of the lamp upon the rear window 
glazing that might be visible to the driver when 
viewed directly, or indirectly in the rearview mir- 
ror. 



PART 571; S 108-7 



(Rev. 7/19/89) 



(b) The high-mounted stop lamps installed in or 
on a vehicle subject to S5. 1.1. 27(b) shall be 
located at the same height, with one vertical edge 
of each lamp on the vertical edge of the body sec- 
tion nearest the vertical centerline. 

(6) In the second column Table III for the 
item "High-mounted stop lamp", the text "1 red, 
for passenger cars only" is revised to read "1 
red". 

(7) In the second column of Table IV for the 
item "High-mounted stop lamp", the text "On 
the rear, on the vertical centerline (See S4.3.1.8), 
effective September 1, 1985, for passenger cars 
only" is revised to read "On the rear, on the ver- 
tical centerline (See S5.1.1.27, S5.3.1.8, and 
Table III)." 

(8) In the fourth column of Table IV for the 
item "High-mounted stop lamp", the text "(See 
S4.3.I.8)" is revised to read "See S5.3.1.8 for 
passenger cars. Not less than 34 inches for multi- 
purpose passenger vehicles, trucks, and buses." 
(56 F.R. 16015— April 19, 1991. Effective: Optional 
compliance, September 1, 1992; Mandatory compli- 
ance September 1, 1993)] 

55.4 Equipment combinations. Two or more 
lamps, reflective devices, or items of associated 
equipment may be combined if the requirements 
for each lamp, reflective device, and item of asso- 
ciated equipment are met, with the following 
exceptions: 

(a) No high-mounted stop lamp shall be com- 
bined with any other lamp or reflective device, 
other than with a cargo lamp. 

(b) No high-mounted stop lamp shall be com- 
bined optically, as defined by SAE Information 
Report J387 Terminology — Motor Vehicle Light- 
ing NOV 87, with any cargo lamp. 

(c) No clearance lamp shall be combined opti- 
cally, as defined by SAE Information Report J387 
Terminology — Motor Vehicle Lighting NOV 87, 
with any tail lamp. 

S5.4.1 Removed. 

(55 F.R. 46669 November 6, 1990.) 

55.5 Special wiring requirements. 

S5.5.1 Each vehicle shall have a means of switch- 
ing between lower and upper beams that conforms 
to SAE Recommended Practice J564a, Headlamp 
Beam Switching. April 1964, or to SAE Rec- 



ommended Practice J565b, Semi-Aittomatic 
Headlamp Beam Switching Devices, February 
1969. Except as provided in S5.5.8, the lower and ^- 
upper beams shall not be energized simultaneously ( 
except momentarily for temporary signalling pur- 
poses or during switching between beams. 

55.5.2 Each vehicle shall have a means for 
indicating to the driver when the upper beams of 
the headlamps are on that conforms to SAE Rec- 
ommended Practice J564a, April 1964, except that 
the signal color need not be red. 

55.5.3 The taillamps on each vehicle shall be acti- 
vated when the headlamps are activated in a 
steady-burning state. 

55.5.4 The stoplamps on each vehicle shall be 
activated upon application of the service brakes. 
The high-mounted stoplamp on each passenger car 
shall be activated only upon application of the 
service brakes. 

55.5.5 The vehicular-hazard warning-signal 
operating unit on each vehicle shall operate 
independently of the ignition or equivalent switch, 

and when activated, shall cause to flash simulta- ^ 

neously sufficient turn signal lamps to meet, as a J^ 

minimum, the turn signal lamp photometric ^?" 
requirements of this standard. 

55.5.6 Each vehicle equipped with a turn signal 
operating unit shall also have an illuminated pilot 
indicator. Failure of one or more turn signal lamps 
to operate shall be indicated in accordance with 
SAE Standard J588e, Turn Signal Lamps, Septem- 
ber 1970, except when a variable-load turn signal 
flasher is used on a truck, bus, or multipurpose 
passenger vehicle 80 or more inches in overall 
width, on a truck that is capable of accommodat- 
ing a slide-in camper, or on any vehicle equipped 
to tow trailers. 

55.5.7 On each passenger car. and motorcycle, 
and multipurpose passenger vehicle, truck, and 
bus of less than 80 inches overall width: 

(a) When the parking lamps are activated, the 
taillamps, license plate lamps, and side marker 
lamps shall also be activated; and 

(b) When the headlamps are activated in a 
steady-burning state, the taillamps, parking lamps. __^ 
license plate lamps and side marker lamps shall I 
also be activated. ^ 



(Rev. 4/19/91) 



PART 571; S 108-8 



55.5.8 On a motor vehicle equipped with a 
^ headhghting system designed to conform to the 
B photometric requirements of Figure 15, the lamps 

marked "L" or "LF'" may be wired to remain 
permanently activated when the lamps marked 
"U" or "LF" are activated. On a motor equipped 
with an Integral Beam headhghting system meet- 
ing the photometric requirements of section 
S7.4(a)(l)(ii), the lower beam headlamps shall be 
wired to remain permanently activated when the 
upper beam headlamps are activated. On a motor 
vehicle equipped with a headhghting system 
designed to conform to the requirements of Figure 
17, a lower beam light source may be wired to 
remain activated when an upper beam light source 
is activated if the lower beam light source contrib- 
utes to compliance of the headhghting system with 
the upper beam requirements of Figure 17. 

55.5.9 Except as provided in Section S5.5.8, the 
wiring harness or connector assembly of each 
headlamp system shall be designed so that only 
those light sources intended for meeting lower 
beam photometries are energized when the beam 

^ selector switch is in the lower beam position, and 

^ that only those light sources intended for meeting 
^ upper beam photometries are energized when the 
beam selector switch is in the upper beam posi- 
tion. 

55.5.10 The wiring requirements for lighting 
equipment in use are: 

(a) Turn signal lamps, hazard warning signal 
lamps, and school bus warning lamps shall be 
wired to flash; 

(b) Headlamps and side-marker lamps may be 
wired to flash for signalling purposes; 

(c) A motorcycle headlamp may be wired to 
allow either its upper beam or its lower beam, but 
not both, to modulate from a higher intensity to 
a lower intensity in accordance with Section S4.6; 

(d) All other lamps shall be wired to be steady- 
burning. 

S5.6 Motorcycle headlamp modulation sys- 
tem. 

S5.6.1 A headlamp on a motorcycle may be wired 
m to modulate either the upper beam or the lower 

" beam from its maximum intensity to a lesser 

intensity provided that: 



(a) The rate of modulation shall be 240 ± 40 
cycles per minute. 

(b) The headlamp shall be operated at maxi- 
mum power for 50 to 70 percent of each cycle. 

(c) The lowest intensity at any test point shall 
be not less than 17 percent of the maximum 
intensity measured at the same point. 

(d) The modulator switch shall be wired in the 
power lead of the beam filament being modulated 
and not in the ground side of the circuit. 

(e) Means shall be provided so that both the 
lower beam and upper beam remain operable in 
the event of a modulator failure. 

(f) The system shall include a sensor mounted 
with the axis of its sensing element perpendicular 
to a horizontal plane. Headlamp modulation shall 
cease whenever the level of light emitted by a 
tungsten filament light operating at 3000° Kelvin 
is either less than 270 lux (25 footcandles) of 
direct light for upward pointing sensors or less 
than 60 lux (5.6 footcandles) of reflected light for 
downward pointing sensors. The light is measured 
by a silicon cell type light meter that is located 
at the sensor and pointing in the same direction 
as the sensor. A Kodak Gray Card (Kodak R-27) 
is placed at ground level to simulate the road sur- 
face in testing downward-pointing sensors. 

(g) When tested in accordance with the test 
profile shown in Figure 9, the voltage drop across 
the modulator when the lamp is on at all test 
conditions for 12-volt systems and 6- volt systems 
shall not be greater than .45 volt. The modulator 
shall meet all the provisions of the standard after 
completion of the test profile shown in Figure 9. 

(h) Means shall be provided so that both the 
lower and upper beam function at design voltage 
when the headlamp control switch is in either the 
lower or upper beam position when the modulator 
is off. 

S5.6.2 (a) Each motorcycle headlamp modulator 
not intended as original equipment, or its con- 
tainer, shall be labeled with the maximum watt- 
age, and the minimum wattage, appropriate for its 
use. Additionally, each such modulator shall com- 
ply with S5.6.1 (a) through (g) when connected to 
a headlamp of the maximum rated power and a 
headlamp of the minimum rated power and shall 
provide means so that the modulated beam func- 
tions at design voltage when the modulator is off. 
(b) Instructions, with a diagram, shall be pro- 
vided for mounting the light sensor including 



PART 571; S 



location on the motorcycle, distance above the 
road surface, and orientation with respect to the 
light. 

[S5.7 Conspicuity Systems. Each trailer of 80 
or more inches overall width, and with a GVWR 
over 10,000 lbs., manufactured on or after Decem- 
ber 1, 1993, except a trailer designed exclusively 
for living or office use, shall be equipped with 
either retroreflective sheeting that meets the 
requirements of S5.7.1, reflex reflectors that meet 
the requirements of S5.7.2, or a combination of 
retroreflective sheeting and reflex reflectors that 
meet the requirement of S5.7.3. 

[S5.7.1 Retroreflective sheeting. Each trailer 
to which S5.7 applies that does not conform to 
S5.7.2 or S5.7.3 shall be equipped with 
retroreflective sheeting that confoiTns to the 
requirements specified in S5.7.1.1 through 
S5.7.1.5. 

[S5.7.1.1 Construction. Retroreflective sheeting 
shall consist of a smooth, flat, transparent exterior 
film with retroreflective elements embedded or 
suspended beneath the film so as to form a non- 
exposed retroreflective optical system. 

[S5.7.1.2 Performance requirements. Retro- 
reflective sheeting shall meet the requirements of 
ASTM D 4956-90, Standard Specification for 
Retroreflective Sheeting for Traffic Control, for 
Type V Sheeting, except for the photometric 
requirements, and shall meet the minimum photo- 
metric performance requirements specified in Fig- 
ure 29. 

[5.7.1.3 Sheeting pattern, dimensions, and 
relative coefficients of retroref lection. 

(a) Retroreflective sheeting shall be applied in 
a pattern of alternating white and red color seg- 
ments to the side and rear of each trailer, and in 
white to the upper rear comers of each trailer, in 
the locations specified in S5.7.1.4, and illustrated 
in Figure 30. 

(b) Except for a segment that is trimmed to 
clear obstructions, or lengthened to provide red 
sheeting near red lamps, each white or red seg- 
ment shall be a length of 300 mm ± 1 50 mm. 

(c) Neither white nor red sheeting shall rep- 
resent more than two thirds of the aggregate of 
any continuous strip marking the width of a 



trailer, or any continuous or broken strip marking 

its length. _ 

(d) Retroreflective sheeting shall have a width ( 
of 50 mm (Grade D0T-C2), 75 mm (Grade 
D0T-C3), or 100 mm (Grade D0T-C4). 

(e) The coefficients for retroreflection of each 
segment of red or white sheeting shall be not less 
than the minimum values specified in Figure 29 
of this standard for grades D0T-C2, D0T-C3, 
and DOT-C4. 

[S5.7.1.4 Location, (a) Retroreflective sheeting 
shall be applied to each trailer on the side and rear 
as specified below, but need not be applied to dis- 
continuous surfaces such as outside ribs, stake 
post pickets on platform trailers, and external 
protruding beams, or to items of equipment such 
as door hinges and lamp bodies. 

(b) The edge of white sheeting shall not be 
located closer than 75 mm to the edge of the 
luminous lens area of any lamp that is required 
by this standard. 

(c) The edge of red sheeting shall not be 
located closer than 75 mm to the edge of the 
luminous lens area of any amber lamp that is 
required by this standard. /"^ 

[S5.7.1.4.1 Rear. Retroreflective sheeting shall 
be applied to the rear of each trailer as follows: 

(a) Element 1: a horizontal strip of sheeting in 
alternating colors across the full width of the 
trailer as close to the extreme edges as prac- 
ticable, and as close as practicable to 1.25 meters 
above the road surface. 

(b) Element 2: two pairs of white strips of 
sheeting, each pair consisting of strips 300 mm 
long of grade D0T-C2 (50 mm wide), D0T-C3 
(75 mm wide), or DOT-C4 (100 mm wide), 
applied horizontally and vertically to the right and 
left upper contours of the body, as viewed from 
the rear, as close to the top of the trailer and as 
far apart as practicable. 

(c) Element 3: a strip of sheeting in alternating 
colors across the full width of the horizontal 
member of the rear underride protection device. 

[S5.7.1.4.2 Side. Retroreflective sheeting shall 
be applied to each side of a trailer as follows: 

(a) A horizontal strip of sheeting in alternating 
colors, originating and terminating as close to the /^ 
front and rear ends as practicable, and as close as ^^ 
practicable to 1.25 m above the road surface 



(Rev. 12/10/92) 



PART 5''1; S 108-10 



except that, at the location chosen, the strip shall 
not be obscured in whole or in part by other 
^k motor vehicle equipment or trailer cargo. The 
^r strip need not be continuous as long as not less 
than half of the length of the trailer is covered 
and the spaces are distributed as evenly as prac- 
ticable. 

(b) If necessary to clear rivet heads or other 
similar obstructions, grade D0T-C2 retro- 
reflective sheeting may be separated into two 25 
mm wide strips of the same length and color, 
separated by a space of not more than 25 mm, 
and used in place of the retroreflective sheeting 
that would otherwise be applied. 

[S5.7.1.5 Certification. The letters DOT-C2. 
D0T-C3, or D0T-C4, as appropriate, constituting 
a certification that the retroreflective sheeting con- 
forms to the requirements of S5.7.1.2, shall appear 
at least once on the exposed surface of each white 
or red segment of retroreflective sheeting, and at 
least once every 300 mm on retroreflective sheet- 
ing that is white only. The characters shall be not 
less than 3 mm high, and shall be permanently 
stamped, etched, molded, or printed in indelible 
^ ink. 

" IS5.7.2 Reflex Reflectors. Each trailer to which 
S5.7 applies that does not conform to S5.7.1 or 
S5.7.3 shall be equipped with reflex reflectors in 
accordance with this section. 

[S5.7.2.1(a) Each reflex reflector shall conform to 
SAE Standard J594f, Reflex Reflectors, January 
1977. 

(b) Each red reflex reflector shall also provide, 
at an observation angle of 0.2 degree, not less 
than 310 millicandelas/lux at any light entrance 
angle between 30 degrees left and 30 degrees 
right, including an entrance angle of degree. 

(c) Each white reflex reflector shall also pro- 
vide, at an observation angle of 0.2 degree, not 
less than 1290 millicandelas/lux at any light 
entrance angle between 30 degrees left and 30 
degrees right, including an entrance angle of 
degree. 

[S5.7.2.2 Reflex reflectors shall be installed 
and located as specified below: 

^ (a) In the same locations and in the same 

m length in which retroreflective sheeting is required 



by S5.7.1.4 to be applied in alternating colors, 
reflex reflectors shall be installed in a repetitive 
pattern of two or three white reflex reflectors 
alternating with two or three red reflex reflectors, 
with the center of each reflector not more than 
100 mm from the center of each adjacent reflec- 
tor. 

(b) In the same locations and in the same 
length in which white retroreflective sheeting is 
required by S5.7.1.4 to be installed, white reflex 
reflectors shall be installed, with the center of 
each white reflex reflector not more than 100 mm 
from the center of each adjacent reflector. 

[S5.7.2.3 Certification. The exposed surface of 
each reflex reflector shall be marked with the let- 
ters DOT-C which constitutes a certification that 
the reflector conforms to all applicable require- 
ments of section 571.108 of this part. The certifi- 
cation shall be not less than 3 mm high, and 
permanently stamped, etched, molded or printed in 
indelible ink. 

[S5.7.3 Combination of sheeting and reflec- 
tors. Each trailer to which S5.7 applies that does 
not conform to S5.7.1 or S5.7.2, shall be equipped 
with retroreflective materials that meet the 
requirements of S5.7.1 except that reflex reflectors 
that meet the requirements of S5.7.2.1, and that 
are installed in accordance with S5.7.2.2, may be 
used instead of any corresponding element of 
retroreflective sheeting located as required by 
S5.7.1.4. (F.R. 58406— December 10, 1992. Effec- 
tive: December 1, 1993)] 

S5.8 Replacement equipment. 

55.8.1 Each lamp, reflective device, or item of 
associated equipment manufactured to replace any 
lamp, reflective device, or item of associated 
equipment on any vehicle to which this standard 
applies, shall be designed to confonn with this 
standard. 

55.8.2 Unless otherwise specified in this standard, 
each lamp, reflective device, or item of associated 
equipment to which section S5.7.1 applies may be 
labeled with the symbol DOT, which shall con- 
stitute a certification that it conforms to applicable 
Federal motor vehicle safety standards. 



PART 571; S 108-11 



(Rev. 12/10/92) 



56 Subreferenced SAE Standards and Rec- 
ommended Practices. 

56.1 SAE Standards and Recommended Practices 
subreferenced by the SAE Standards and Rec- 
ommended Practices included in Tables I and III 
and paragraphs S5.1.4 and S5.5.1 are those pub- 
lished in the 1970 edition of the SAE Handbook, 
except that the SAE standard referred to as 
"J575" is J575e, Tests for Motor Vehicle Lighting 
Devices and Components, August 1970, for 
stoplamps, designed to conform to SAE Standards 
J586c, J586 FEB 84, and J 1398 MAY 85; for 
taillamps designed to conform to SAE Standards 
J585d and J585e; for turn signal lamps designed 
to conform to SAE Standards J588e. J588 NOV 
84, and J 1395 APR 85; and for high-mounted 
stoplamps designed to conform to SAE Rec- 
ommended Practice J 186a. The reference in J585e 
to J256 does not apply. For headlamps, unless 
otherwise specified in this standard, the version of 
SAE Standard J575 is DEC 88, and the version of 
SAE Standard J602 is OCT 80. The definition of 
"optically combined" in SAE Information Report 
J387 Terminology — Motor Vehicle Lighting NOV 
87, applies to that term as used in J586c and 
J588e. 

56.2 Requirements of SAE Standards incorporated 
by reference in this standard, other than J576b and 
J576c, do not include tests for warpage of devices 
with plastic lenses. 

56.3 The term "effective projected luminous lens 
area" has the same meaning as the term "func- 
tional lighted lens area" in any SAE Standard or 
Recommended Practice incorporated by reference 
or by subreference in this standard. 

57 Headlighting requirements. 

57.1 Each passenger car, multipurpose passenger 
vehicle, truck, and bus shall be equipped with a 
headlighting system designed to conform to the 
requirements of S7.3, S7.4, or S7.5. 

57.2 (a) The lens of each original and replacement 
equipment headlamp, and of each original equip- 
ment and replacement equipment beam contributor 
manufactured on or after December 1, 1989, shall 
be marked with the symbol "DOT," either hori- 
zontally or vertically which shall constitute the 
certification required by 15 U.S.C. 1403. 



(b) The lens of each headlamp and of each 
beam contributor manufactured on or after 
December 1, 1989, to which paragraph (a) of this — 
section applies shall be marked with the name V 
and/or trademark registered with the U.S. Patent 

and Trademark Office of the manufacturer of 
such headlamp or beam contributor, or its 
importer, or any manufacturer of a vehicle 
equipped with such headlamp or beam contribu- 
tor. Nothing in this paragraph shall be construed 
to authorize the marking of any such name and/ 
or trademark by one who is not the owner, unless 
the owner has consented to it. 

(c) Each headlamp and beam contributor to 
which paragraph (a) of this section applies shall 
be marked with its voltage and with its part or 
trade number. 

S7.3 Sealed beam headlighting system. A 

sealed beam headlighting system shall be designed 
to meet the requirements of one of the following 
subparagraphs of S7.3.2 through S7.3.9. In ref- 
erences to Figures in SAE J 1383 APR 85 for 
headlamp dimensional requirements, only those 
dimensions marked "I" for interchangeability are 
applicable. 

57.3.1 The lens of each sealed beam headlamp ^ 
designed to conform to S7.3.2 through S7.3.6 shall 

be marked according to paragraph 5.4.3 through 
5.4.5 of SAE Standard J 1383 April 85 Perform- 
ance Requirements for Motor Vehicle Headlamps. 

57.3.2 Type A headlighting system. A Type A 
headlighting system consists of two Type 1 Al and 
two Type 2A1 headlamps and associated hard- 
ware, which are designed to conform to the fol- 
lowing requirements: 

(a) SAE Standard J 1383 APR 85 Performance 
Requirements for Motor Vehicle Headlamps, with 
the following exceptions: 

(1) Paragraphs 1, 2.1.2, 2.8.2, 3, 4.1.1, 4.1.2, 
4.1.3, 4.4, 4.6, 4.8 through 4.18, 5.1.1, 5.1.3, 
5.1.5, 5.1.7 through 5.1.16. 5.2.2, 5.3.5, 5.4.1, 
5.4.2, and 6 through 6.4 do not apply. 

(2) In paragraph 5.3.2, the words "and 
retaining rings" are omitted. 

(3) In paragraphs 4.5.2 and 5.1.6, the words 
"either Table 1 or Table 2 of SAE J579 DEC 84 

as appropriate" are substituted for "Table 3." a 

(b) SAE Standard J580 DEC 86 Sealed Beam ( 
Headlamp Assembly (except paragraphs 3, 4.1.1, 



PART 571; S 108-12 



5.1.1.1, 5.1.2.3, and the second sentence of 5.1.6); 
^ in 5.2.1, delete the words "and retaining rings;" 

^^ the correct reference is SAE J 1383 Figure 6, 9, 12 
^ and 14. 

(c) After a vibration test conducted in accord- 
ance with paragraph S8.8, there shall be no evi- 
dence of loose or broken parts, other than fila- 
ments, visible without magnification. 

(d) The maximum wattage at 12.8 volts (design 
voltage): Single filament headlamp, 55 watts on 
the upper beam; dual filament headlamp, 43 watts 
on the upper beam and 65 watts on the lower 
beam. 

S7.3.3 Type B headlighting system. A Type B 
headlighting system consists of two Type 2B1 
headlamps and associated hardware, which are 
designed to conform to the following require- 
ments: 

(a) The requirements of paiagraphs S7.3.2(a) 
through (c). 

(b) The maximum wattage at 12.8 volts (design 
voltage): 70 watts on the upper beam and 60 
watts on the lower beam. 

^ S7.3.4 Type C headlighting system. A Type C 

H headlighting system consists of two Type ICl and 
two Type 2C1 headlamps and associated hard- 
ware, which are designed to conform to the 
requirements of paragraph S7.3.2(a) through (d). 

57.3.5 Type D headlighting system, (a) A 

Type D headlighting system consists of two Type 
2D1 headlamps and associated hardware, which 
are designed to conform to the requirements of 
paragraph S7.3.2(a) through (c). 

[(b) The maximum wattage at 12.8 volts 
(design voltage): 65 watts on upper beam, and 55 
watts on lower beam. (55 F.R. 4424 — February 8, 
1990. Effective: March 12, 1990.)] 

57.3.6 Type E headlighting system, (a) A 

Type E headlighting system consists of two Type 
2E1 headlamps and associated hardware, which 
are designed to conform to the requirements of 
paragraph S7.3.2(a) through (c). 

[(b) The maximum wattage at 12.8 vohs 
(design voltage): 70 watts on upper beam, and 60 
watts on lower beam. (55 F.R. 4424 — February 8, 
^ 1990. Effective: March 12, 1990.)] 

" S7.3.7 Type F headlighting system. A Type F 

headlighting system consists of two Type UP and 



two Type LP headlamps and associated hardware, 
which are designed to conform to the following 
requirements: 

(a) Figures 11, 12, 13, and 14 as appropriate. 

(b) The photometric requirements of Figure 15 
of this standard. A realm tolerance of ± V4 degree 
is allowed for any test point on the Type LF lamp 
when tested alone, but is not allowed on the Type 
UF lamp when tested alone. For the test point 
10U-90U, measurement shall be from the nor- 
mally exposed surface of the lens face. 

(c) SAE Standard J 1383 APR 85 Performance 
Requirements for Motor Vehicle Headlamps, Sec- 
tions 2.4, 2.5, 2.6, 4.1, 4.1.4 and [5.1.4]. 

(d) When tested in accordance with section (c), 
the mounted assembly (either Type UP or Type 
LF headlamps, respective mounting ring, aiming 
ring, and aim adjustment mechanism) shall be 
designed to conform to the requirements of Figure 
15 for upper or lower beams respectively without 
realm when any conforming Type UF or LF 
headlamp is tested and replaced by another 
conforming headlamp of the same Type. 

(e) SAE J580 DEC 86 Sealed Beam Headlamp 
Assembly with the following exceptions: 

(1) Section 2.2 Mounting Ring reads: "the 
adjustable ring upon which the sealed beam unit 
is mounted and which forces the sealed beam unit 
to seat against the aiming ring when assembled 
into a sealed beam assembly." 

(2) The definition "2.3 Aiming Ring" reads: 
"The clamping ring that retains the sealed beam 
unit against the mounting ring, and that provides 
an interface between the unit's aiming/seating 
pads and the headlamp aimer adapter (locating 
plate)." 

(3) Section 4.1.1 Vibration Test does not 
apply. 

(4) Section 5.1.1.1 [and 5.1.2.3] do not 
apply. 

(5) Section 5.1.2.1 reads: "When the 
headlamp assembly is tested in the laboratory, a 
minimum aiming adjustment of ± 2.5 degrees 
shall be provided in the horizontal plane and ± 4 
degrees in the vertical plane." 

(6) Section 5.1.2.2 concludes: "... through 
an angle of ± 2.5 degrees and ± 4 degrees respec- 
tively." 

(7) Section 5.1.6 is retitled "Retaining Ring/ 
Aiming Ring Tests." The phrase "92 x 
150mm . . . 0.340 in (8.6 mm)" is added at the 



PART 571; S 1( 



(Rev. 2/8/90) 



end of the table for flange thickness. The sentence 
beginning 'The fastening means" is deleted. (55 
F.R. 4424— February 8, 1990. Effective: March 12, 
1990)] 

(8) Figures 2, 3, and 4 do not apply, and the 
reference to them in section 4.5 is replaced by 
"Figure 16, Deflectometer, of Federal Motor 
Vehicle Safety Standard No. 108." 

(f) A lens for a Type F headlamp incorporating 
an upper beam shall be labeled "UF". A lens for 
a Type F headlamp incorporating a lower beam 
shall be labeled "LF". The face of letters, num- 
bers, or other symbols molded on the surface of 
the lens shall not be raised more than 0.020 in. 
(0.5 mm), and shall be placed no closer to the 
geometric center of the lens than 1.375 in (35 
mm). The marking shall be molded in the lens 
and shall be not less than Va in. (6.35 mm.) in 
size. 

(g) The maximum wattage at 12.8 volts (design 
voltage): 70 watts on the upper beam and 60 
watts on the lower beam. 

(h) Type F headlamps may be mounted on 
common or parallel seating and aiming planes to 
permit simultaneous aiming of both headlamps 
provided that when tested with any conforming 
Type UF and LF headlamps according to Section 
SIO: 

(1) The assembly (consisting of the Type UF 
and LF headlamps, mounting rings, the aiming/ 
seating rings, and aim adjustment mechanism), 
shall be designed to conform to the test point val- 
ues of Figure 15. 

(2) There shall be no provision for adjust- 
ment between the common or parallel aiming and 
seating planes of the two lamps. 

(i) After a vibration test conducted in 
accordance with paragraph S8.8, the Type F 
system shall show no evidence of loose or bro- 
ken parts, other than filaments, visible without 
magnification. 

S7.3.8 Type G headlighting system. A Type G 
headlamp system consists of two Type IGl 
headlamps and two Type 20 1 headlamps each of 
which is designed to conform to the following 
requirements: 

(a) Figures 1 8 and 2 1 . 

(b) SAE Standard J 1383 APR 85 Performance 
Requirements for Motor Vehicle Headlamps 
(except paragraphs 1, 2.1.2, 2.8.2, 3, 4.1.1, 4.1.2, 
4.1.3, 4.4, 4.6, 4.8 through 4.18, 5.1.1, 5.1.3, 



5.1.5 through 5.1.16, 5.2.2, 5.3.5 through 6.4). In 
paragraph 5.3.2 the words "and retaining rings" 

are omitted. In paragraph 4.5.2, the words either i" 
Table 1 or Table 2 or SAE J579 DEC 84. as ^ 
appropriate" are substituted for the words "Table 
3." 

(c) SAE Standard J580 DEC 86 Sealed Beam 
Headlamp Assembly, with the following excep- 
tion: 

(1) Sections 2.2, 2.3, 4.1.1, 5.1.1.1, 5.1.2.3, 

5.1.6 and 5.2.1. 

(2) Section 4.5 reads: '"Torque Deflection 
Test. The headlamp assembly to be tested shall be 
mounted in the designed vehicle position and set 
at nominal aim (0.0). A special adapter (Figure 
22) for the deflectometer (Figure 3) shall be 
clamped onto the headlamp assembly. A torque of 
20 in.-lbs. (2.25 N-m) shall be applied to the 
headlamp assembly through the deflectometer, 
and a reading on the thumb wheel shall be taken. 
The torque shall be removed and a second read- 
ing on the thumb wheel shall be taken." 

(d) After a vibration test conducted in accord- 
ance with paragraph S8.8, there shall be no evi- 
dence of loose or broken parts, other than fila- 
ments, visible without magnification. /^ 

(e) The maximum wattage at 12.8 volts (design 
voltage) for the IGl and 2G1 upper beam is 55 
watts and 43 watts respectively; for the 2GI 
lower beam, 65 watts. 

(f) A lens for a Type G headlamp incorporating 
only part of an upper beam shall be labeled IGl. 
A lens for a Type G headlamp incorporating both 
parts of an upper beam and a lower beam shall 
be labeled 2G1. The face of letters, numbers, or 
other symbols molded on the surface of the lens 
shall not be raised more than 0.020 in. (0.5 mm.), 
and shall be placed no closer to the geometric 
center of the lens than 1.375 in. (35 mm.). The 
marking shall be molded in the lens and shall be 
not less than '/i in. (6.35 mm) in size. 

S7.3.9 Type H headlighting system. A Type H 
headlamp system consisting of two Type 2H1 
headlamps and associated hardware, which are 
designed to conform to the following require- 
ments: 

(a) Paragraph S7.3.8(a) through (d). 

(b) The maximum wattage at 12.8 volts (design /*■ 
voltage): 70 watts on the upper beam and 60 I 
watts on the lower beam. 



(Rev. 2/8/90) 



PART 571; S 



(c) A lens for a Type H headlamp incorporat- 
ing both an upper beam and a lower beam shall 
be labeled 2H1. The face of letters, numbers, or 
other symbols molded on the surface of the lens 
shall not be raised more than 0.020 in. (0.5 mm), 
and shall be placed no closer to the geometric 
center of the lens than 1.375 in. (35 mm.) The 
marking shall be molded in the lens and shall be 
not less than '/i in. (6.35 mm) in size. 

S7.4 Integral Beam Headlighting System. An 

integral beam headlighting system shall be 
designed to conform to the following require- 
ments: 

(a) The system shall provide in total not more 
than two upper beams and two lower beams of 
the performance described in one of the follow- 
ing: 

(1) In a four-headlamp system, each upper 
beam headlamp and each lower beam headlamp 
shall be designed to conform to the photometries 
of one of the following: 

(i) Figure 15; 

(ii) Figure 15 except that the upper beam test 
values at 21/2 D-V and 2'/2 D-12R and 12L 
shall apply to the lower headlamp and not to 
the upper beam headlamp, and the upper beam 
test point value at I'/i D-9R and 9L shall be 
1,000, or 

(iii) Table 2 of SAE J579 DEC 84. 

(2) In a two-headlamp system, each 
headlamp shall be designed to conform to the 
photometries of one of the following: 

(i) Figure 17; or 

(ii) Table 1 of SAE J579 DEC 84. 

(3) In a system in which there is more than 
one beam contributor providing a lower beam, 
and/or more than one beam contributor providing 
an upper beam, each beam contributor in the sys- 
tem shall be designed to meet only the photo- 
metric performance requirements of Figure 15 
based upon the following mathematical expres- 
sion: conforming test point value = 2 (Figure 15 
test point value)/total number of lower or upper 
beam contributors for the vehicle, as appropriate. 
The system shall be designed to use the Vehicle 
Headlamp Aiming Device (VHAD) as specified 
in paragraph S7.8.5.2. 

(b) The lower and upper beams shall be pro- 
vided only as follows where each headlamp con- 
tains two light sources: 



(1) The lower beam shall be provided either 
by the most outboard light source (or the upper- 
most if arranged vertically), or by all light 
sources. 

(2) The upper beam shall be provided either 
by the most inboard light source (or the upper- 
most if arranged vertically), or by all light 
sources. 

(c) The lower and upper beams shall be pro- 
vided only as follows where each headlamp con- 
tains a signal light source. 

(1) The lower beam shall be provided by the 
most outboard headlamps (or the uppermost if 
arranged vertically), and the lens of each such 
headlamp shall be permanently marked with the 
letter "L." 

(2) The upper shall be provided by the most 
inboard headlamps (or lowermost if arranged ver- 
tically), and the lens of each such headlamp shall 
be permanently marked with the letter "U." 

(d) A tolerance of ± Va degree realm tolerance 
during photometric performance tests is permitted 
for any headlamp. The test points 10U-90U shall 
be measured from the normally exposed surface 
of the lens face. 

(e) A headlamp or beam contributor designed 
to meet paragraphs (a)(1) or (a)(3) of this section 
and S7.8.5.1 may be mounted in an assembly to 
permit simultaneous aiming of the beam(s) 
contributors, provided that with any complying 
contributor the assembly complete with all lamps 
meets the appropriate photometric requirements 
when tested in accordance with SIO. 

(f) Each integral beam headlamp system shall 
be designed to conform to the applicable photo- 
metric performance requirements in paragraph (a) 
of this section when tested in accordance with 
Sections 4.1 and 4.1.4 of SAE Standard J 1383 
APR 85 with any headlamp intended for use in 
such system. The term "aiming plane" means 
"aiming reference plane," or an appropriate verti- 
cal plane defined by the manufacturer as required 
in paragraph S7.8.1. 

(g) The system shall be aimable in accordance 
with the requirements of paragraph S7.8. A sys- 
tem that incorporates any headlamp or beam 
contributor that does not have a VHAD as an 
integral and indivisible part of the headlamp or 
beam contributor shall be designed so that the 
appropriate photometries are met when any cor- 
rectly aimed and photometrically conforming 
headlamp or beam contributor is removed from its 



PART 571; S 108-15 



mounting and aiming mechanism, and is replaced 
without reaim by any conforming headlamp or 
beam contributor of the same type. 

(h) A headlamp with a glass lens need not meet 
the abrasion resistance test (S8.2), or the chemical 
resistance test (S8.3), or impact (S8.8) tests. If. in 
addition to a glass lens, the headlamp uses a 
nonplastic reflector, it need not meet the internal 
heat test of paragraph S8.6.2. A headlamp of 
sealed design as verified in paragraph S8.9 Seal- 
ing need not meet the con-osion (S8.4), dust 
(S8.5), or humidity (S8.7) tests, however, the 
headlamp shall meet the requirements of para- 
graphs 4.1, 4.1.2, 4.4 and 5.1.4 for corrosion and 
connector of SAE Standard J580 DEC 86 Sealed 
Beam Headlamp Assembly. 

(i) When tested according to any of the proce- 
dures indicated in subparagraphs (1) through (7) 
each headlamp or beam contributor shall meet the 
appropriate requirement: 

(1) After an abrasion test conducted in 
accordance with paragraph S8.2, the headlamp 
shall meet the photometric requirements 
applicable to the headlamp system under test. 

(2) After a chemical resistance test involving 
exposure to any of the fluids listed in paragraph 
S8.3, there shall be no surface deterioration, coat- 
ing delamination, fractures, deterioration of bond- 
ing materials, color bleeding or color pickup visi- 
ble without magnification, and the headlamp shall 
meet the photometric requirements applicable to 
the headlamp system under test. 

(3) After a coiTosion test conducted in 
accordance with paragraph S8.4 there shall be no 
evidence of external or internal corrosion or rust 
visible without magnification. Loss of adhesion of 
any applied coating shall not occur more than 
0.125 in. (3.2 mm) from any shaip edge on the 
inside or outside. Corrosion may occur on termi- 
nals only if the current produced during the test 
of paragraph S8.4(c) is not less than 9.7 amperes. 

(4) After a dust test conducted in accordance 
with paragraph S8.5, the headlamp shall meet the 
photometric requirements applicable to the 
headlamp system under test. 

(5) The headlamp shall first meet the 
requirements of subparagraph (i) and then those 
of subparagraph (ii). 

(i) After a temperature cycle test conducted 
in accordance with paragraph S8.6. 1, the 
headlamp shall show no evidence of 
delamination, fractures, entry of moisture or 



deterioration of bonding material, color bleed- 
ing, warpage or deformation visible without 
magnification or lens warpage greater than .118 f^" 
in. (3 mm) when measured parallel to the opti- * 
cal axis at the point of intersection of the axis 
of each light source with the exterior surface of 
the lens, and it shall meet the photometric 
requirements applicable to the headlamp system 
under test. 

(ii) After an internal heat test conducted in 
accordance with paragraph S8.6.2, there shall 
be no lens warpage greater than .118 in. (3 
mm) when measured parallel to the optical axis 
at the point of intersection of the axis of each 
light source with the exterior surface of the 
lens, and it shall meet the photometric require- 
ments applicable to the headlamp system under 
test. 

(6) After a humidity test conducted in 
accordance with paragraph S8.7, the inside of the 
headlamp shall show no evidence of delamination 
or moisture, fogging or condensation visible with- 
out magnification. 

(7) After a vibration test conducted in 
accordance with paragraph S8.8, there shall be no 
evidence of loose or broken parts, other than fila- ^ 
ments, visible without magnification. V^ 

S7.5 Replaceable Bulb Headlamp System. 

Each replaceable bulb headlamp system shall 
be designed to conform to the following require- 
ments: 

(a) The system shall provide only two lower 
beams and two upper beams and shall incorporate 
not more than two standardized replaceable light 
sources in each headlamp. 

(b) The photometries as specified in paragraphs 
(c) through (e) of this section (depicted in Figure 
26), using any standardized light source of the 
Type intended for use in such system. 

(c) The test requirements of sections 4.1, 4.1.4, 
and performance requirements of section 5.1.4 of 
SAE J 1383 April 85, using die photometric 
requirements specified in paragraphs (d) and (e) 
of this section. The term "aiming plane" means 
"aiming reference plane," or an appropriate verti- 
cal plane defined by the manufacturer as required 
in paragraph [S7.8.1.] A Va degree reaim toler- 
ance is permitted for any test point. The test . 
points 10U-90U shall be measured from the nor- I 
mally exposed surface of the lens face. 



PART 571; S 108-16 



(d) For a headlamp system equipped with dual 
filament light sources. Type HBl light sources. 
Type HB2 light sources. Type HB5 light sources, 
or Types HBl and HB5 in combination, the fol- 
lowing requirements apply: 

(1) Headlamps designed to conform to the 
external aiming requirements of [S7.8.5.1] shall 
have no mechanism that allows adjustment of an 
individual light source, or, if there are two light 
sources, independent adjustment of each reflector. 

(2) The lower and upper beams of a 
headlamp system consisting of two lamps, each 
containing one or two light sources, shall be pro- 
vided as follows: 

(i) The lower beam shall be provided in one 
of the following ways: 

(A) By the outboard light source (or upper 
one if arranged vertically) designed to conform 
to: 

( 1 ) the lower beam requirements of Fig- 
ure 17, if the light sources are type HB2; or 

(B) Both light sources, in the headlamp 
designed to confoirn to the lower beam require- 
ments specified above for their Type. 

(ii) The upper beam shall be provided in one 
of the following ways: 

(A) By the inboard light source (or the 
lower one if arranged vertically) designed to 
conform to: 

(1) the upper beam requirements of 
Table 1 of SAE Standard J579 DEC 84, if the 
light sources are only Type HBl; or Type HB5, 
or a combination thereof; or 

(2) the upper beam requirements of Fig- 
ure 17, if the light sources are Type HB2; or 

(B) By both light sources in the headlamp, 
designed to conform to the upper beam 
photometries specified above for their type. 

(3) The lower and upper beams of a 
headlamp system consisting of four lamps, each 
containing a single light source, shall be provided 
as follows: 

(i) The lower beam shall be provided by the 
outboard lamp (or upper one if arranged verti- 
cally), designed to conform to: 

(A) the lower beam requirements of Table 
1 of SAE Standard J579 DEC 84, if the light 
sources are only Type HBl; or Type HB5, or 
a combination thereof; or 

(B) the lower beam requirements of Figure 
15, if the light sources are Type HB2. The lens 



of each such headlamp shall be marked with 
the letter "L." 

(ii) The upper beam shall be provided by the 
inboard lamp (or the lower one if arranged ver- 
tically), designed to conform to: 

(A) the upper beam requirements of Table 
1 of SAE Standard J579 DEC 84, if the light 
sources are only Type HBl; or Type HB5, or 
a combination thereof; or 

(B) the upper beam requirements of Figure 
15, if the light sources are Type HB2. The lens 
of each such headlamp shall be marked with 
the letter "'U." 

(e) The following requirements apply to a 
headlamp system equipped with any combination 
of light sources except those specified in para- 
graph (d) of this section: 

[(1) Headlamps designed to conform to the 
external requirements of S7.8.5.1 shall have no 
mechanism that allows adjustment of an individ- 
ual light source, or, if there are two light sources, 
independent adjustment of each reflector. (57 F.R, 
32738— July 23, 1992. Effective: August 24, 1992)] 

(2) The lower and upper beams of a 
headlamp system consisting of two lamps, each 
containing two light sources (other than those 
specified in paragraph (d) of this section) shall be 
provided only as follows: 

(i) The lower beam shall be provided in one 
of the following ways: 

(A) By the outboard light source (or the 
uppermost if arranged vertically) designed to 
conform to the lower beam requirements of 
Figure 17; or 

(B) By both light sources, designed to 
conform to the lower beam requirements of 
Figure 17. 

(ii) The upper beam shall be provided in one 
of the following ways: 

(A) By the inboard light source (or the 
lower one if arranged vertically) designed to 
conform to the upper beam requirements of 
Figure 17; or 

(B) By both light sources, designed to 
conform to the upper beam requirements of 
Figure 17. 

(3) The lower and upper beams of a 
headlamp system consisting of four lamps, using 
any combination of light sources except those 
specified in paragraph (d) of this section, each 
lamp containing only a single light source, shall 
be provided only as follows: 



PART 571; S 108-17 



(Rev. 7/23/92) 



(i) The lower beam shall be produced by the 
outboard lamp (or upper one if arranged verti- 
cally), designed to conform to the lower beam 
requirements of Figure 15. The lens of each 
such headlamp shall be permanently marked 
with the letter "L." 

(ii) The upper beam shall be produced by the 
inboard lamp (or lower one if arranged verti- 
cally), designed to conform to the upper beam 
requirements of Figure 15. The lens of each 
such headlamp shall be marked with the letter 

(f) Each lens reflector unit manufactured as 
replacement equipment shall be designed to con- 
form to the requirements of paragraphs (d) and 
(e) of this section when any standardized replace- 
able light source appropriate for such unit is 
inserted in it. 

(g) The lens of each replaceable bulb headlamp 
using any Type light source, except HBl used 
singly or dually, within a headlamp system on a 
motor vehicle, shall permanently display the Type 
designation for that light source on the lens in 
front of each light source. 

(h) The system shall be aimable in accordance 
with paragraph [S7.8.] 

(i) Each headlamp shall meet the requirements 
of paragraphs S7.4(h) and (i), except that the sen- 
tence in (h) to verify sealing according to S8.9 
Sealing does not apply. 

[S7.6 Combination IHeadlighting System. A 

combination headlighting system shall be com- 
prised of either two headlamps designed to con- 
form to the requirements of S7.6.2, or any com- 
bination of four headlamps designed to conform to 
the requirements of S7.3.7, S7.4, or S7.5 of this 
standard. 

[S7.6.1 A combination headlighting system shall 
provide in total not more than two upper beams 
and two lower beams. When installed on a motor 
vehicle, the headlamps (or parts thereof) that pro- 
vide the lower beam shall be of the same type, 
and provide a symmetrical effective projected 
luminous lens area when illuminated. 

[S7.6.2 In a combination headlighting system 
consisting of two headlamps, each headlamp shall 
be designed to conform to Figure 17, and shall be 
a combination of two different headlamps chosen 
from the following types: a Type F headlamp, an 



integral beam headlamp, and a replaceable bulb 
headlamp. 

[S7.6.2.1 That part of the headlamp which con- ( 
tains an integral beam headlamp, or beam 
contributors used in place of a single headlamp, 
shall be designed to conform to the requirements 
of S7.4(c) through (i) of this standard. 

[S7.6.2.2 That part of the headlamp which con- 
tains a replaceable bulb headlamp shall be 
designed to conform to the requirements of S7.5 
of this standard. 

[S7.6.3 In a combination headlighting system 
consisting of four headlamps, each headlamp shall 
be designed to conform to Figure 15, or if an 
integral beam headlamp in which there is more 
than one beam contributor, designed to conform to 
Figure 15 in the manner required by S7.4(a)(3) of 
this standard. (57 F.R, 32738— July 23, 1992. Effec- 
tive: August 24, 1992)] 

[S7.7] Standardized Replaceable Light 
Sources. Each standardized replaceable light 
source shall be designed to conform to the follow- 
ing requirements: 

(a) A Type HBl light source shall be designed | 
to conform to the dimensions specified in Figure ^ 
3 and shall incorporate a silicone 0-ring. Its 
maximum power on the lower beam shall be 50 
watts, and on the upper beam, 70 watts. Its lumi- 
nous flux in lumens shall be 700 ± 15% on the 
lower beam and 1200 ± 15% on the upper beam. 

(b) A Type HB2 light source shall be designed 
to conform to the dimensions specified in Figure 
23. Its maximum power on the lower beam shall 
be 65 watts, and on the upper beam, 72 watts. Its 
luminous flux in lumens shall be 910 plus or 
minus 10% on the lower beam, and 1500 plus or 
minus 10% on the upper beam. 

(c) A Type HB3 light source shall be designed 
to conform to the dimensions specified in Figure 

19. Its maximum power on the upper beam shall 
be 70 watts. Its luminous flux in lumens shall be 
1700 ± 12%. 

(d) A Type HB4 light source shall be designed 
to conform to the dimensions specified in Figure 

20. Its maximum power shall be 60 watts on the 
lower beam, and its luminous flux in lumens on 

the lower beam shall be 1000 ± 15%. | 

(e) A Type HB5 light source shall be designed f 
to conform to the dimensions specified in Figure 



(Rev. 7/23/92) 



PART 571; S 108-1 i 



24. Its maximum power shall be 60 watts on the 
lower beam, and 70 watts on the upper beam. Its 
luminous flux in lumens shall be 1000 ± 15% on 
the lower beam, and 1350 ± 15% on the upper 
beam. 

(f) The filament of a light source shall be sea- 
soned before measurement of maximum power 
and luminous flux. 

(g) Measurement of maximum power and lumi- 
nous flux shall be made with the direct current 
test voltage regulated within one quarter of one 
percent. The test voltage shall be design voltage, 
12.8v. The measurement of luminous flux shall be 
in accordance with the Illuminating Engineering 
Society of North America, LM^5; lES Approved 
Method for Electrical and Photometric Measure- 
ments of General Service Incandescent Filament 
Lamps (April 1980), shall be made with the black 
cap installed on Types HBl. HB2, and HB4, and 
Type HB5, and shall be made with the electrical 
conductor and light source base shrouded with an 
opaque white colored cover, except for the por- 
tion normally located within the interior of the 
lamp housing. The measurement of luminous flux 
for the Types HB3 and HB4 shall be with the 
base covered with a white cover shown in Figures 
19-1 and 20-1. The white covers are used to 
eliminate the likelihood of incorrect lumen 
measurement that will occur should the reflec- 
tance of the light source base and electrical 
connector be low. 

(h) The capsule, lead wires and/or terminals, 
and seal on each Type HBl, Type HB3, Type 
HB4, and Type HB5 light source shall be 
installed in the base as shown in Figure 25 so as 
to provide an airtight seal. Such a seal exists 
when no air bubbles shall appear on the low pres- 
sure (connector) side after the light source has 
been immersed in water for one minute while 
inserted in a cylindrical aperture specified for the 
light source in Figure 25, and subjected to an air 
pressure of 70 kPa (10 P.S.I.G.) on the glass cap- 
sule side. 

(i) After the force deflection test conducted in 
accordance with 59, the permanent deflection of 
the glass envelope shall not exceed 0.005 in. 
(0.13mm) in the direction of the applied force. 

(j) A general tolerance shall apply to Figure 3 
as follows: ± 0.004 in. (0.10 mm) to all linear 
dimensions and ± 1 degree 00 minutes to all 
angular dimensions except for refefenced dimen- 
sions and unless otherwise specified. 



(k) Each standardized light source manufac- 
tured on or after December 1, 1989, shall be 
marked with the symbol DOT and with a name 
or trademark in accordance with S7.2. In addition, 
the base of each such light source shall be marked 
with its HB Type designation. 

[S7.8] Aimability Performance Requirements. 

[S7.8.1] Each headlamp (other than a headlamp 
designed to conform to paragraph S7.3), or beam 
contributor, shall be equipped with fiducial marks, 
aiming pads or similar references of sufficient 
detail and accuracy for determination of an appro- 
priate vehicle plane to be used with the photo- 
metric procedures of SAE J 1383 APR 85 for cor- 
rect alignment with the photometer axis when 
being tested for photometric compliance, and to 
serve for the aiming reference when the lamp is 
installed on a motor vehicle. The fiducial marks, 
aiming pads, or similar references are protrusions, 
bubble vials, holes, indentations, ridges, scribed 
lines, or other readily identifiable marks estab- 
lished and described by the vehicle or lamp manu- 
facturer. 

[S7.8.2] Each headlamp shall be installed on a 
motor vehicle with a mounting and aiming mecha- 
nism that allows aim inspection and adjustment of 
both vertical and horizontal aim, and is accessible 
for those uses without removal of any vehicle 
parts, except for protective covers removable with- 
out the use of tools. 

[S7.8.2.1] (a) When installed on the vehicle, 
adjustment of one aim axis through its full on- 
vehicle range shall not cause the aim of the other 
axis to deviate more than ± 0.76 degree. 

(b) If the performance specified in paragraph 
(a) of this section is not achievable, the require- 
ments of paragraph [S7. 8. 5. 2(b)(3)] apply, except 
that if the aiming mechanism is not a VHAD, the 
requirements specific to VHADs are not 
applicable, and the instructions shall be specific to 
the aiming mechanism installed. 

[S7.8.2.2] If a headlamp is aimed by moving the 
reflector relative to the lens and headlamp hous- 
ing, or vice versa, it shall conform with the 
photometries applicable to it with the lens at any 
position relative to the reflector within the aim 
range limits of paragraphs [S7.8.3] and [S7.8.4,] 
or any combination. 



PART 571: S 108-19 



(Rev. 7/23/92) 



[S7.8.3] When a headlamp system is tested in a 
laboratory, the range of its vertical aim shall not 
be less than ± 4 degrees from the nominal correct 
air position for the intended vehicle appHcation. 
When installed on a motor vehicle, the range of 
vertical aim shall be not less than the full range 
of pitch of the vehicle on which the headlamp sys- 
tem is installed. The installed range of static pitch 
angle shall as a minimum be determined from 
unloaded vehicle weight to gross vehicle weight 
rating, and incorporate pitch angle effects from 
maximum trailer or truck loadings, the full range 
of tire intemiix sizes and suspensions rec- 
ommended and/or installed by the vehicle manu- 
facturer, and the anticipated effects of variable 
passenger loading. The vertical aim adjustment 
mechanism shall be continuously adjustable over 
the full range. 

[S7.8.4] When a headlamp system is tested in a 
laboratory, the range of its horizontal aim shall be 
not less than 2.5 degrees from the nominal correct 
aim position for the intended vehicle application. 

[S7.8.5] When a headlamp system is installed on 
a motor vehicle, it shall be aimable with either an 
externally applied aiming device or on-vehicle 
headlamp aiming devices installed by the vehicle 
manufacturer. When activated in a steady-burning 
state, headlamps shall not have any styling orna- 
ment or other feature, such as a translucent cover 
or grill, in front of the lens. Headlamp wipers may 
be used in front of the lens provided that the 
headlamp system is designed to confomi with all 
applicable photometric requirements with the 
wiper stopper in any position in front of the lens. 

[S7.8.5.1] External aiming, (a) The aim of the 

headlamps in each headlamp system, other than a 
headlamp system designed to conform to section 
S7.3, that is designed to use such external aiming 
devices, shall not deviate more than 0.30 degree 
when a downward torque of 20 in. -lb. (2.25 N-m) 
is removed from the headlamp in its design 
operating position. The downward force used to 
create the torque shall be applied parallel to the 
aiming reference plane, through the aiming pads, 
and displaced forward using a lever arm such that 
the force is applied on an axis that is prpendicular 
to the aiming reference plane and originates at the 



center of the aiming pad pattern (see Figures 4- 
1 and 4-3). For headlamps using the aiming pad 
locations of Group 1, the distance between the ^ 
point of application of force and the aiming ref- ' 
erence plane shall be not less than 6.625 in. (168.3 
mm) plus the distance from the aiming reference 
plane to the secondary plane, if used {see section 
[S7.8.5. 1(d)(1)).] For headlamps using the aiming 
pad locations of Group II, the distance between 
the point of application of force and the aiming 
reference plane shall be not less than 6.609 in. 
(167.9 mm) plus the distance from the aiming ref- 
erence plane to the secondary plane, if used. For 
headlamps using the nonadjustable Headlamp 
Aiming Device Locating Plates for the 146 mm 
diameter, the 176 mm diameter, and the 92 x 150 
mm sealed beam units, the distance between the 
point of application of force and the aiming plane 
shall, respectively, be not less than 6.984 in. 
(177.4 mm), 6.937 in. (176.2 mm), and 7.625 in. 
(193.7 mm). 

Each headlamp system that is designed to con- 
form to paragraph S7.5 and that is designed to 
use such external aiming devices, and which is 
manufactured on or after December 1, 1989, shall 
comply with this paragraph. ^^ 

(b) When a headlamp is installed on a motor ^^ 
vehicle, its aim in any direction shall not change 

by more than 0.30 degree nor shall the lamp 
recede more than 0.1 in. (2.5 mm) after being 
subjected to an inward force of 50 pounds (222 
newtons) applied evenly to the lens parallel to the 
mechanical axis. 

(c) Each headlamp system mounting and aim- 
ing mechanism shall be subjected to a salt spray 
(fog) test in accordance with ASTM B 1 17-73 
Method of Salt Spray (Fog) Testing for a period 
of 50 hours, consisting of two successive 25 hour 
periods of 24 hours exposure followed by 1 hour 
of drying. At the end of 50 hours, the headlamp 
system shall be capable of meeting any of the 
applicable requirements of paragraph [S7.8.] 

(d) Each headlamp system which is designed to 
use the Headlamp Aiming Device Locating Plates 
with adjustable legs for the 100 x 165 mm unit 
and the 142 x 200 mm unit, and which has 
adjustable length legs, shall meet the requirements 
of subparagraphs (1) and (2) below. 



(Rev. 7/23/92) 



PART 571; S 108-20 



Figure 2. — Minimum Luminous Intensity Plate for the 100 x 165 mm unit, the 142 x 200 
Requirement for Backup Lamps mm unit, the 146 mm diameter unit, or the 178 
mm diameter unit of SAE J602, or the 92 x 150 

Group Test point, degrees °'de\a{se7note 7" tnm Type F unit, and incorporate lens mounted 
aiming pads as specified for those units in Figures 

1' 45L-5U, 45L-H, 45L-5D 45 , r, i ? c n .■^■ c a c moi! add 

: 10, 13, 5, or 7 respectively m SAE J 1383 APR 

2' 30L-H, 30L-5D 50 85, or Figure 11 of this standard for the Type F 

~^ '^^^ 10L-5U. V- 100 ""'^- ^^ ^° designed, no additional lens marking is 

' lou, V-5U, lOR-iou. necessary to designate the type of plate or dimen- 

10R-5U. sions. 

' 'VloR-n'm-fD.''^ "'" [S7.8.5.2] On-vehicle aiming. Each headlamp 

'- system that is capable of being aimed by equip- 

5 ' 30R-H, 30R-5D 50 ^gj^t installed on the vehicle shall include a 

6 ' 45R-5U 45R-H, 45R-5D 45 Vehicle Headlamp Aiming Device ( VHAD) that 

conforms to the following requirements: 

' When 2 lamps of the same or symmetrically opposite design are , -. . ■ -r-i ^rtxAT^ u n j r u ji 

used, the reading along the vertical axis and the averages of the (a) Aim. The VHAD Shall provide tor headlamp 

readings for the same angles left and right of vertical for 1 lamp ^jj. inspection and adjustment in both the vertical 

shall be used to determine compliance with the requirements. If 2 ^ J 

lamps of differing designs are used, they shall be tested individually and horizontal aXCS. 

twfceleTl^ddaleluir^Ltr'" '''' ""^ '=°"'""'' ""'" ■""' (D Vertical aim: The VHAD shall include 

When only I backup lamp is used on the vehicle, it shall he []^q necessary references and scales relative to the 

tested to twice the candela requirements. , . , , • i ■ r 

horizontal plane to assure correct vertical aim ror 

(1) The lens shall have three aiming pads photometry and aiming purposes. An off- vehicle 
which meet the requirements of Figure 4, Dimen- measurement of the angle of the plane of the 
sional Specifications for Location of Aiming Pads ground is permitted. In addition, an equal number 
on Replaceable Bulb Headlamp Units. The aiming of graduations from the "O" position represent- 
pads need not be centered at the geometric center ing angular changes in the axis in the upward and 
of the lens, or on the optical axis. Except as pro- downward directions shall be provided. 

vided in subparagraph (2), a whole number, (i) Each graduation shall represent a change 

which represents the distance in tenths of an inch in the vertical position of the mechanical axis 

(i.e., 0.3 inch=3) from the aiming reference plane not larger then 0.19 degree (1 in. at 25 ft.) to 

to the respective aiming pads which are not in provide for variations in aim at least 1.2 

contact with that plane, shall be inscribed adjacent degrees above and below the horizontal, and 

to each respective aiming pad on the lens. The have an accuracy relative to the zero mark of 

height of these numbers shall be not less than less than 0.1 degree. 

.157 in. (4 mm). If there is interference between (ii) The VHAD shall be marked to indicate 

the plane and the area of the lens between the headlamp aim movement in the upward and 

aiming pads, the whole number represents the dis- downward directions. 

tance to a secondary plane. The secondary plane (iii) Each graduation shall indicate a linear 
shall be located parallel to the aiming reference movement of the scale indicator of not less 
plane and as close to the lens as possible without than 0.05 in. (1.27 mm) if a direct reading ana- 
causing interference. log indicator is used. If a remote reading 

(2) If the most forward aiming pad is the indicator is provided, it shall represent the 
lower inboard aiming pad, then the dimensions actual aim movement in a clear, understandable 
may be placed anywhere on the lens. The dimen- format. 

sion for the outboard aiming pad (Dimension F in (iv) The vertical indicator shall perform 

Figure 4) shall be followed by the letter "H"" and through a minimum range of ± 1.2 degrees, 

the dimension for the center aiming pad shall be (v) Means shall be provided in the VHAD 

followed by the letter "V." The dimensions shall for compensation for deviations in floor slope 

be expressed in tenths of an inch. not less than 1.2 degrees from the horizontal 

(e) Each headlamp may be designed to use the that would affect the correct positioning of the 

nonadjustable Headlamp Aiming Device Locating headlamp for vertical aim. 

PART 57 1; S 108-2 1 (Rev. 7/23«2) 



(vi) The graduations shall be legible under 
an illumination level not greater than 30 foot 
candles, measured at the top of the graduation, 
by an observer having 20/20 vision (Snellen), 
and shall permit aim adjustment to within 0.19 
degree (1 in. at 25 ft.). 

(2) Horizontal aim. The VHAD shall include 
references and scales relative to the longitudinal 
axis of the vehicle necessary to assure correct 
horizontal aim for photometry and aiming pur- 
poses. An "O" mark shall be used to indicate 
alignment of the headlamps relative to the 
longitudinal axis of the vehicle. In addition, an 
equal number of graduations from the "O" posi- 
tion representing equal angular changes in the 
axis relative to the vehicle axis shall be provided, 
(i) Each graduation shall represent a change 
in the horizontal position of the mechanical 
axis not greater than 0.35 degree (2 in. at 25 
ft.) to provide for variations in aim at least 0.76 
degree (4 in. at 25 ft.) to the left and right of 
the longitudinal axis of the vehicle, and shall 
have an accuracy relative to the zero mark of 
less than 0. 1 degree. 

(ii) The VHAD shall be marked to indicate 
headlamp aim movement in the left and right 
directions. 

(iii) The graduations shall be legible under 
an illumination level not greater than 30 foot 
candles, measured at the top of the top of the 
radiator, by an observer having 20/20 vision 
(Snellen), and shall permit aim adjustment to 
within 0.38 degree (2 in. at 25 ft.). 

(iv) The horizontal indicator shall perform 
through a minimum range of ± 0.76 degree (4 
in. at 25 ft.); however, the indicator itself shall 
be capable of recalibration over a movement of 
± 2.5 degrees relative to the longitudinal axis 
of the vehicle to accommodate any adjustment 
necessary for recalibrating the indicator after 
vehicle repair from accident damage, 
(b) Aiming instructions. (1) The instructions for 
properly aiming the headlighting system using the 
VHAD shall be provided on a label permanently 
affixed to the vehicle adjacent to the VHAD, or 
in the vehicle operator's manual. The instructions 
shall advise that the headlighting system is prop- 
erly aimed if the appropriate vertical plane (as 
defined by the vehicle manufacturer) is per- 
pendicular to both the longitudinal axis of the 
vehicle, and a horizontal plane when the vehicle 



is on a horizontal surface, and the VHAD is set 
at "O" vertical and "O" horizontal. ^ 

(2) Should a remote indicator or a remote I 
indicator and adjuster be provided, the instruc- 
tions shall be placed in the operator's manual, and 
may also be placed on a label adjacent to the 
VHAD. 

(3) Should the mechanism not meet the require- 
ments of [S7.8.2.1,] on each motor vehicle 
manufactured on or after September 1, 1990, a 
cautionary label shall be placed adjacent to the 
mechanism stating the caution and including 
either the reason for the caution or the corrective 
action necessary. Each such label shall also refer 
the reader to the vehicle operator's manual for 
complete instructions. Each such vehicle shall be 
equipped with an operator's manual containing 
the complete instructions appropriate for the 
mechanism installed. 

(c) Testing the VHAD. 

(1) The headlamp assembly (the headlamp(s) 
and the VHAD(s) mechanism) shall be mounted 
on a level goniometer, aligned to a photometer 
located not less than 60 ft. (18.3m) from the 
VHAD assembly. The assembly shall be mechani- 
cally aimed using the VHAD in accordance with /^ 
the manufacturer's instructions as provided with 

the vehicle on which the VHAD is intended to be 
used. A '/4 degree realm is permitted in any direc- 
tion at any test point to allow for variations in 
readings between laboratories. The test shall be 
conducted in accordance with the procedures of 
paragraphs 4.1 and 4.1.4 of SAE J 1383 APR 85. 
Under these conditions the mounted headlamp 
assembly shall be designed to conform to the 
photometric requirements appropriate for the 
headlamp system under test. 

(2) When tested in accordance with sub- 
section (1) of this section, with any replacement 
headlamp unit(s) or light sources intended for use 
in the system under test, the VHAD and 
headlamp system shall be designed to conform to 
the photometric performance requirements appro- 
priate for the system under test. 

(3) The same VHAD and associated 
headlamp(s) (or headlamp assembly) shall be rig- 
idly mounted in a headlamp test fixture and com- 
ply with the following laboratory test procedures: 

(i) Each graduation on the horizontal and . 
vertical aim scales shall be checked and any » 
variation from the correct aim shall not exceed 
± 0.2 degree, and ± 0.1 degree, respectively. 



(Rev. 7/23/92) 



PART 571; S 108-22 



(ii) With the aiming plane horizontal and 
vertical and with the scale on the device set at 
O, the aimer shall be adjusted before each of 
the following tests to assure that the indicators 
are centered at O. 

(ii)(A) The VHAD and an unlighted 
headlamp assembly shall be stabilized at 20 ± 
degrees F (-7 ± 3 degrees C) in a circulating 
air environmental test chamber. After a period 
of 30 minutes, when measured at that soak 
temperature, the variation from correct hori- 
zontal or vertical aim shall not exceed ± 0.2 
degree, and ± 0. 1 degree, respectively. 

(ii)(B) The VHAD, and the headlamp assem- 
bly with its highest wattage filament (or com- 
bination of filaments intended to be used 
simultaneously) energized at its design voltage, 
shall than be stabilized at 100 ± 5 degrees F 
(38 ± 3 degrees C) in a circulating air environ- 
mental test chamber. After a period of 30 min- 
utes, when measured at that soak temperature, 
the variation from correct horizontal and verti- 
cal aim shall not exceed ± 0.2 degree, and ± 
0.1 degree, respectively. 

(ii)(c) The VHAD and an unlighted 
headlamp assembly shall then be placed in a 
circulating air environmental test chamber and 
exposed to a temperature of 140 ± 5 degrees F 
(60 ± 3 degrees C) for 24 hours, followed by 
a temperature of -40 + 5 degrees F ( - 40 ± 
3 degrees C) for 24 hours and then permitted 
to return to room temperature, after which the 
VHAD and headlamp assembly shall show no 
damage which would impair its ability to per- 
form as specified herein. The variation from 
correct horizontal or vertical aim shall not 
exceed ± 0.2 degree, and ± 0.1 degree, respec- 
tively. 

(ii)(d) The VHAD and headlamp assembly 
shall then be tested according to the corrosion 
test procedure of paragraph [S7. 8. 5. 1(c).] 

(ii)(E) The VHAD and headlamp assembly 
shall then be tested for photometric compliance 
as specified in paragraphs [S7.7.5.2(c)(l) and 
(2).] 

S8 Tests and Procedures for Integral Beam 
and Replaceable Bulb Headlighting Systems. 

When tested in accordance with the following 
procedures, each integral beam headlamp shall 
meet the requirements of paragraph S7.4, and each 



replaceable bulb headlamp shall meet the require- 
ments of paragraph S7.5. 

58.1 Photometry. Each headlamp to which 
paragraph S8 applies shall be tested according to 
paragraphs 4.1 and 4.1.4 of SAE Standard J 1383 
APR 85 for meeting the applicable photometric 
requirements, after each test specified in para- 
graphs S8.2, S8.3, S8.5, S8.6.1, S8.6.2, and S8.7. 
A Va degree realm is permitted in any direction at 
any testpoint. 

58.2 Abrasion, (a) A headlamp shall be 
mounted in the abrasion-test fixture in the manner 
indicated in Figure 5 with the lens facing upward. 

(b) An abrading pad meeting the requirements 
in paragraphs (c)(1) through (c)(4) of this section 
shall be cycled back and forth (1 cycle) for 11 
cycles at 4±0.8 in. (10 cm ± 2 cm) per second 
over at least 80 percent of the lens surface, 
including all the area between the upper and 
lower aiming pads, but not including lens covers 
and edges. 

(c)(1) The abrading pad shall be not less than 
1.0 ± .04 in. (2.5 cm ± .1 cm) wide, constructed 
of 0000 steel wool, and rubber cemented to a 
rigid base shaped to the same vertical contour of 
the lens. The "grain" of the pad shall be per- 
pendicular to the direction of motion. 

(2) The abrading pad support shall be equal 
in size to the pad and the center of the support 
surface shall be within ± .08 in. (± 2 mm) of par- 
allel to the lens surface. 

(3) The density of the abrading pad shall be 
such that when the pad is mounted to its support 
and is resting unweighted on the lens, the base of 
the pad shall be no closer than .125 in. (3.2 mm) 
to the lens at its closest point. 

(4) When mounted on its support and resting 
on the lens of the test headlamp, the abrading pad 
shall then be weighted such that a pad pressure of 
2.0 ± .15 psi (14 ± 1 kPa) exists at the center and 
perpendicular to the face of the lens. 

(d) A pivot shall be used if it is required to fol- 
low the contour of the lens. 

(e) Unused steel wool shall be used for each 
test. 

58.3 Chemical resistance, (a) The entire exte- 
rior lens surface of the fixtured headlamp and top 
surface of the lens-reflector joint shall be wiped 
once to the left and once to the right with a 6- 



PART571; S 108-23 



(Rev. 7/23/92) 



inch square soft cotton cloth (with pressure 
equally applied) which has been saturated once in 
a container with 2 ounces of one of the test fluids 
listed in paragraph (b) of this section. The lamp 
shall be wiped within 5 seconds after removal of 
the cloth from the test fluid. 

(b) The test fluids are: 

(1) ASTM Reference Fuel C, which is com- 
posed of Isooctane 50 volume % and Toluene 50 
volume %. Isooctane must conform to A2.7 in 
Annex 2 of the Motor Fuels Section of the 1985 
Annual Book of ASTM Standards Vol. 05.04, and 
Toluene must conform to ASTM specification 
D362-84, Standard Specification for Industrial 
Grade Toluene. ASTM Reference Fuel C must be 
used as specified in: 

(i) Paragraph A2.3.2 and A2.3.3 of Annex 2 
to Motor Fuels, Section 1 in the 1985 Annual 
Book of ASTM Standards; and 

(ii) OSHA Standard 29 CFR 1910.106— 
Handling Storage and Use of Flammable 
Combustible Liquids. 

(2) Tar remover (consisting by volume of 
45% xylene and 55% petroleum base mineral 
spirits). 

(3) Power steering fluid (as specified by the 
vehicle manufacturer for use in the motor vehicle 
on which the headlamp is intended to be 
installed). 

(4) Windshield washer fluid consisting of 
0.5% monoethanolamine with the remainder 50% 
concentrations of methanol/distilled water by vol- 
ume. 

(5) Antifreeze (50% concentration of ethyl- 
ene glycol/distilled water by volume). 

(c) After the headlamp has been wiped with the 
test fluid, it shall be stored in designed operating 
attitude for 48 hours at a temperature of 73 ° F 
± 7° (23°C ± 4°) and a relative humidity of 30 
± 10 percent. At the end of the 48-hour period, 
the headlamp shall be wiped clean with a soft dry 
cotton cloth and visually inspected. 

[S8.4] Corrosion, (a) A connector test shall be 
performed on each filament circuit prior to the test 
in subparagraph (b) according to Figure 1 of SAE 
Standard J580, [DEC 86 J. The power source shall 
be set to provide 12.8 volts and the resistance 
shall be set to produce 10 amperes. 

(b) The headlamp with connector attached to 
the terminals, unfixtured and in its designed 
operating attitude with all drain holes, breathing 



devices or other designed openings in their nor- 
mal operating positions, shall be subjected to a 
salt spray (fog) test in accordance with ASTM t" 
B 117-73, Method of Salt Spray (FOG) Testing. 
for a period of 240 hours, consisting of 10 
successive 24-hour periods. During each interval, 
the headlamp shall be mounted in the middle of 
the chamber and exposed for 23 hours to the salt 
spray. The spray shall not be activated for the 
24th hour. The bulb shall be removed from the 
headlamp and from the test chamber during the 
one hour of salt spray deactivation and reinserted 
for the start of the next test cycle, at the end of 
the first and last three 23-hour periods of salt 
spray exposure, and at the end of any two of the 
fourth through seventh 23-hour periods of salt- 
spray exposure. The test chamber shall be closed 
at all times except for a maximum of 2 minutes 
which is allowed for removal or replacement of 
a bulb during each period. After the ten cycles, 
the lens reflector unit without the bulb shall be 
immersed in deionized water for five minutes, 
then secured and allowed to dry by natural 
convection only. 

(c) Using the voltage, resistance and pretest 
setup of subparagraph (a), the current in each fila- ^ 
ment circuit shall be measured after the test con- ^ 
ducted in subparagraph (b). 

[S8.5] Dust. The headlamp, mounted on a 
headlamp test fixture, with all drain holes, breath- 
ing devices or other designed openings in their 
normal operating positions, shall be positioned 
within a cubical box, with inside measurements of 
35.4 in. (900 mm) on each side, or larger if 
required for adequate wall clearance, i.e., a dis- 
tance of at least 5.9 in. (150 mm) between the 
headlamp and any wall of the box. The box shall 
contain 9.9 lb. (4.5 kg) of fine powdered cement 
which conforms to the ASTM CI 50-77 Specifica- 
tion for Portland Cement. Every 15 minutes, the 
cement shall be agitated by compressed air or fan 
blower(s) by projecting blasts of air for a 2-second 
period in a downward direction so that the cement 
is diffused as uniformly as possible throughout the 
entire box. This test shall be continued for five 
hours, after which the exterior surfaces of the 
headlamp shall be wiped clean. 

S8.6 Temperature and Internal heat test. A £'' 

headlamp with one or more standardized replace- " 
able light sources shall be tested according to 



(Rev. 5/9/92) 



PART 571; S 108-24 



S8.6.1 and S8.6.2. Tests shall be made with all 
filaments lighted at design voltage that are 
intended to be used simultaneously in the 
headlamp and which in combination draw the 
highest total wattage. These include but are not 
limited to filaments used for turn signal lamps, fog 
lamps, parking lamps, and headlamp lower beams 
lighted with upper beams when the wiring harness 
is so connected on the vehicle. If a turn signal is 
included in the headlamp assembly, it shall be 
operated at 90 flashes a minute with a 75 ± 2% 
current "on time". If the lamp produces both the 
upper and lower beam, it shall be tested in both 
the upper beam mode and the lower beam mode 
under the conditions above described, except for a 
headlamp with a single Type HBl or HB2 light 



58.6.1 Temperature cycle. A headlamp 
mounted on a headlamp test fixture, shall be sub- 
jected to 10 complete consecutive cycles having 
the thermal cycle profile shown in Figure 6. Dur- 
ing the hot cycle, the lamp shall be energized 
commencing at point "A" of Figure 6 and de- 
energized at point "B." Separate or single test 

k chambers may be used to generate the environ- 
W ment of Figure 6. All drain holes, breathing 
devices or other openings or vents of the 
headlamp shall be in their normal operating posi- 
tions. 

58.6.2 internal Heat Test, (a) The headlamp 
lens surface that would normally be exposed to 
road dirt shall be unifonnly sprayed with any 
appropriate mixture of dust and water or other 
appropriate materials to reduce the photometric 
output at the H-V test point of the upper beam (or 
the '/2D-I '/2R test point of the lower beam as 
appropriate) to 25 ± 2% of the output originally 
measured in the photometric test conducted pursu- 
ant to paragraphs S7.4(i), or S7.5(a) through (e), 
as applicable. A headlamp with a single Type 
HBl or HB2 light source shall be tested on the 
upper beam only. 

Such reduction shall be determined under the 
same conditions as that of the original photo- 
metric measurement. 

(b) After the photometric output of the lamp 
has been reduced as specified in paragraph (a), 
I the lamp and its mounting hardware shall be 

mounted in an environmental chamber in a man- 
ner similar to that indicated in Figure 7, Din/ 



Ambient Test Setup. The headlamp shall be 
soaked for one hour at a temperature of 95 -I- 7- 
degrees F (35-1-4-0 degrees C) and then the 
lamp shall be energized according to S8.6 for one 
hour in a still air condition, allowing the tempera- 
ture to rise from the soak temperature. 

(c) The lamp shall be returned to a room 
ambient temperature of 73 -I- 7-0 degrees F 
(23 -f- 4 — degrees C) and a relative humidity of 
30 ± 10% and allowed to stabilize to the room 
ambient temperature. The lens shall then be 
cleaned. 

S8.7 Humidity, [(a) The test fixture consists of 
a horizontal steel plate to which three threaded 
steel or aluminum rods of V2 inch diameter are 
screwed vertically behind the headlamp. The 
headlamp assembly is clamped to the vertical 
rods, which are behind the headlamp. All attach- 
ments to the headlamp assembly are made behind 
the lens and vents or openings, are not within 2 
inches laterally of a vent inlet or outlet. 

(b) The mounted headlamp assembly is ori- 
ented in its design operating position, and is 
placed in a controlled environment at a tempera- 
ture of 1 00-1- 7-0 degrees F (38-1-4-0 degrees 
C) with a relative humidity of not less than 90 
percent. All drain holes, breathing devices, and 
other openings are in their normal operation posi- 
tions for all phases of the humidity test. The 
headlamp shall be subjected to 24 consecutive 3- 
hour test cycles. In each cycle, it shall be ener- 
gized for 1 hour at design voltage with the high- 
est combination of filament wattages that are 
intended to be used, and then deenergized for 2 
hours. If the headlamp incorporates a turn signal, 
it shall flash at 90 flashes per minute with a 75 
± 2 percent current "on-time." 

(c) Within 3 minutes after the completion of 
the 24th cycle, the air flow test will begin. The 
following shall occur: the mounted assembly shall 
be removed, placed in an insulating box and cov- 
ered with foam material so that there is no visible 
air space around the assembly; the box shall be 
closed, taken to the air flow test chamber, and 
placed within it. Inside the chamber, the assembly 
with respect to the airflow, shall be oriented in its 
design operating position. The assembly is posi- 
tioned in the chamber so that the center of the 
lens is in the center of the opening of the air flow 
entry during the test. The headlamp has at least 
3 inches clearance on all sides, and at least 4 



PART 571; S 108-25 



(Rev. 3/11/91) 



inches to the entry and exit ducts at the closest 
points. If vent tubes are used which extend below 
the lamp body, the 3 inches are measured from 
the bottom of the vent tube or its protection. The 
temperature of the chamber is 73 + 4-0 degrees 
F (23 + 4 — degrees C) with a relative humidity 
of 30+10 — percent. The headlamp is not ener- 
gized. 

(d) Before the test specified in paragraph (e) of 
this section, the uniformity of the air flow in the 
empty test chamber at a plane 4 inches down- 
stream of the air entry duct shall have been meas- 
ured over a 4-inch square grid. The uniformity of 
air flow at each grid point is + 10 percent of the 
average air flow specified in paragraph (e) of this 
section. 

(e) The mounted assembly in the chamber shall 
be exposed, for one hour, to an average flow of 
330 + 0-30 ft/min. as measured with an air 
velocity measuring probe having an accuracy of ± 
3 percent in the 330 ft/min. range. The average 
air flow is the average of the velocity recorded at 
six points around the perimeter of the lens. The 
six points are determined as follows: at the center 
of the lens, construct a horizontal plane. The first 
two points are located in the plane, 1 inch out- 
ward from the intersection of the plane and each 
edge of the lens. Then, trisect the distance 
between these two points and construct longitu- 
dinal vertical planes at the two intermediate loca- 
tions formed by the trisection. The four remaining 
points are located in the vertical planes, one inch 
above the top edge of the lens, and one inch 
below the bottom edge of the lens. 

(f) After one hour, the headlamp is removed 
and inspected for moisture. (56 F.R. 10185 — 
March 11, 1991. Effective: September 9, 1991)] 

S8.8 Vibration. A vibration test shall be con- 
ducted in accordance with the procedures of SAE 
Standard J575e Tests for Motor Vehicle Lighting 
Devices and Components August 1970, and the 
following: The table on the adapter plate shall be 
of sufficient size to completely contain the test 
fixture base with no overhang. The vibration shall 
be applied in the vertical axis of the headlamp 
system as mounted on the vehicle. The filament 
shall not be energized. 

[S8.9 Sealing. An unfixtured headlamp in its 
design mounting position shall be placed in water 
at a temperature of 176 ± 5 degrees F (60 ± 3 



degrees C) for one hour. The headlamp shall be 
energized in its highest wattage mode, with the 
test voltage at 12.8 + 0.1 V. during immersion. • 
The lamp shall then be de-energized and imme- 
diately submerged in its design mounting position 
into water at 32 +5-0 degrees F (0 +3-0 
degrees C). The water shall be in a pressurized 
vessel, and the pressure shall be increased to psi 
(70 kPa), upon placing the lamp in the water. The 
lamp shall remain in the pressurized vessel for a 
period of thirty minutes. This entire procedure 
shall be repeated for four cycles. Then the lamp 
shall be inspected for any signs of water on its 
interior. During the high temperature portion of 
the cycles, the lamp shall be observed for signs of 
air escaping from its interior. If any water occurs 
on the interior or air escapes, the lamp is not a 
sealed lamp. 

S9 Deflection test for standardized replace- 
able light sources. With the light source rigidly 
mounted in a fixture in a manner indicated in Fig- 
ure 8, a force of 4.0 ± 0.1 pounds (17.8 ± 0.4N) 
is applied at a distance "A" from the reference 
plane perpendicular to the longitudinal axis of the 
glass capsule and parallel to the smallest dimen- 
sion of the pressed glass capsule seal. The force • 
shall be applied (using a rod with a hard rubber 
tip with a minimum spherical radius of .039 in ( 1 
mm) radially to the surface of the glass capsule in 
four locations in a plane parallel to the reference 
plane and spaced at a distance "A" from that 
plane. These force applications shall be spaced 90 
degrees apart starting at the point perpendicular to 
the smallest dimension of the pressed seal of the 
glass capsule. The bulb deflection shall be meas- 
ured at the glass capsule surface at 180 degrees 
opposite to the force application. 

S10 Simultaneous Aim Photometry Tests. 

(a) Type F Headlamp Systems. The assembly 
shall be located on a goniometer placed not less 
than 60 feet (18.3 m) from the photometer. The 
LF unit shall be aimed mechanically by centering 
the unit on the photometer axis and by aligning 
the aiming plane of the lens perpendicular to the 
photometer axis. Then the assembly shall be 
moved in a plane parallel to the established aim- 
ing plane of the LF headlamp until the UF 
headlamp is centered on the photometer axis. 
Photometry measurements of the UF photometry 1 

unit shall be completed using the aiming plane so 
established, and the procedures of section S4.1 



(Rev. 3/11/91) 



PART 571; S 108-26 



and 4.1.4 Standard J1383 APR 85, and Figure 15. 
A realm tolerance of ± '/t degree is permitted in 
any direction at any test point. 

(b) Integral Beam Headlamp Systems. The 
assembly used for simultaneously aiming more 
than one integral beam headlamp shall be placed 
on a test fixture on a goniometer located not less 
than 60 feet (18.3 m) from the photometer. The 
assembly shall be aimed by centering the geo- 
metric center of the lower beam lens(es) on the 
photometer axis and by aligning the photometer 
axis to be perpendicular to the aiming reference 
plane or appropriate vertical plane defined by the 
manufacturer of any lower beam contributor. 
Photometric compliance of the lower beam shall 



be determined with all lower beam contributors 
illuminated and in accordance with sections 4.1 
and 4.1.6 of SAE Standard J 1383 APR 85, and 
Figure 15. The assembly shall then be moved in 
a plane parallel to the established aiming plane of 
the lower beam until the assembly is located with 
the geometric center of the upper lens(es) on the 
photometer axis. Photometric compliance for 
upper beam shall now be determined using the 
figure and procedure specified for the lower 
beam. During photometric testing, a '/» degree 
realm is permitted in any direction at any test 
point. 

35 F.R. 16842 
October 31, 1970 



PART 571; S 108-27 



(Rev. 3/11/91) 



Table I. — Required Motor Vehicle Lighting Equipment Other Than Headlamps — Multipurpose Passenger 
Vehicles, Trucks, Trailers, and Buses, of 80 or More Inches Overall Width 



Item 


Multipurpose passenger vehicles, 
trucks and buses 




Trailers 


Applicable SAE standards or 
recommended practice 


Column 1 




Column 2 




Column 3 


Column 4 


Taillamps^ 


2 red 




2 red 




J585e. September 1977 


Stoplamps 


2 red 




2 red 




SAE Jl 398 May 1985 


License plate lamp ' 


1 while 




1 white 




J587, October 1981 


Reflex reflectors 


4 red; 2 


amber 


4 red; 2 amber 


J594f, January 1977 


Side marker lamps 


4 red; 2 


amber 


2 red; 2 amber 


J592e, July 1972 


Backup lamp ' 


1 white 




None 




J593C, February 1968 


Turn signal lamps 


2 red or amber; 2 amber 


2 red or amber 


SAE J 1395 April 1985 


Turn signal operating unit ' 


1 




None 




J589. April 1964 


Turn signal flasher 


1 




None 




J590b. October 1965 


Vehicular hazard warning signal op- 
erating unit 


1 




None 




J910. January 1966 


Vehicular hazard warning signal 
flasher 


1 




None 




J945. February 1966 


Identification lamps 


3 amber; 


3 red 


3 red 




J592e, July 1972 


Clearance lamps 


2 amber; 


2 red 


2 amber; : 


2 red 


J592e. July 1972 


Intermediate side marker lamps * 


2 amber 




2 amber 




J592e, July 1972 


Intermediate side reflex reflectors ■* 
[Conspicuity 


2 amber 
See S5.7 




2 amber 
See S.5.7 




J594f. January 1977 
See S5.7] 



(57 F.R. 58406— December 10, 1992, Effective: December 1, 1993.) 

'See S5. 1.1. 10. -See S5. 1.1.1 1-12. 'SeeS5.5.6. -"See S5. 



PART 571: S 108-29 



(Rev. 12/10/92) 



-Location of Required Motor Veiiicle Lighting Equipment Multipurpose Passenger Vehicles, 
Trucks. Trailers, and Buses, Of 80 Or More Inches Overall Width 



Column 2 

On the from, each headlamp provid- Not required 
ing the upper beam, at the same 
height, 1 on each side of the verti- 
cal centerline, each headlamp pro- 
viding the lower beam, at the same 
height. 1 on each side of the verti- 
cal centerline, as far apart as prac- 
ticable. See also S7 



Taillamps 



On the rear, 1 on each side of the On the rear, 1 on each side of the Not less than !5 inches, nor more 
vertical centerline, at the same vertical centerline, at the same than 72 inches, 
height, and as far apart as prac- height, and as far apan as prac- 



Stoplamps 



On the rear, 1 on each side of the 
vertical centerline, at the same 
height, and as far apart as prac- 



On the rear. 1 


on each side of the 


Not less than 15 inches. 


nor more 


vertical ceni 


terline. at the same 


than 72 inches. 




height, and 


as far apart as prac- 






ticable 









License-plate lamp 



At rear license plate, to illuminate the At rear license plate to ill 
plate from the top or sides plate from the top or sides 



the No requirement. 



On the rear 



Not required 



Turn-signal lamps 



At or near the front — ! amber on 
each side of the vertical centerline. 
at the same height, and as far apart 
as practicable. 

On the rear — 1 red or amber on each 
side of the vertical centerline. at 
the same height, and as far apart as 
practicable 



On the rear — I red or amber on each 
side of the vertical centerline, at 
the same height, and as far apart as 
practicable 



inches, nor more 



Identification lamps 



On the front and rear — i lamps, 
amber in front, red in rear, as close 
as practicable to the top of the ve- 
hicle, at the same height, as close 
as practicable to the vertical cen- 
terline with lamp centers spaced 
not less than 6 inches or more than 
12 inches apart. Alternatively, the 
front lamps may be located as 
close as practicable to the top of 
the cab 



On the rear — 3 lamps as close as 
practicable to the top of the vehicle 
at the same height, as close as 
practicable to the vertical center- 
line, with lamp centers spaced not 
less than 6 inches or more than 12 
inches apart.) 



On the front only — No part of the 
lamp or mountings shall extend 
below the top of the vehicle's 
windshield. 



Clearance lamps 



On the front and rear — 2 amber On the 



lamps on front, 2 red lamps on 
rear, to indicate the overall width 
of the vehicle, one on each side of 
the vertical centerline, at the same 
height, and as near the top as prac- 
ticable 



and rear — 2 amber No requirement. 



lamps on front, 2 red lamps on 
rear, to indicate the overall width 
of the vehicle, one on each side of 
the vertical centerline, at the same 
height, and as near the top thereof 
as practicable 



Intermediate side 
marker lamps 



On each side — 1 amber lamp located On each side — 1 amber lamp located Not less than 15 inches, 
the midpoint between at or near the midpoint between 



the front 
lamps 



and rear side-marker 



the front and 
lamps 



side marker 



Intermediate side re- 
flex reflectors 



IConspicuity 



On each side — 1 amber located at oi 
near the midpoint between the 
front and rear side reflex reflectors 

See S5.7 See S.5.7 



On each side — 1 amber located at or 
near the midpoint between the 
front and rear side reflex reflectors 



15 inches nor more 



See S5.7] 



Reflex reflectors 



On the rear — 1 red on each side of On the rear — 1 red on each side of 



the vertical centerline, as far apart 
as practicable, and at the same 
height. 
On each side — 1 red as far to the rear 
as practicable, and 1 amber as far 
to the front as practicable 



the vertical centerline, as far apart 
as practicable, and at the same 
height. 
On each side — 1 red as far to the rear 
as practicable, and 1 amber as far 
to the front as practicable 



(Rev. 12/10/92) 



PART 571; S 108-30 



-Location of Required Motor Vehicle Lighting Equipment Multipurpose Passenger Vehicles, 
Trucks, Trailers, and Buses, Of 80 Or More Inches Overall Width — Continued 



Side marker lamps On each side — 1 red as far to the rear On each side — 1 red as far to the rear Not less than 15 inches, and on the 

as practicable, and 1 amber as far as practicable, and 1 amber as far rear of trailers not more than 60 
to the front as practicable to the front as practicable inches. 



[54 F.R. 58406— December 10, 1992. Effective: December 1, 1993] 



PART 571; S 108-31 



(Rev. 12/10/92) 



Table III. — Required Motor Vehicle Lighting Equipment All Passenger Cars and Motorcycles, and 
Multipurpose Passenger Vehicles, Trucks, Trailers, and Buses, of Less Than 80 Inches Overall Width 



Item 


■ Passenger cars, multipurpose 

passenger vehicles, trucks. 

and buses 


Trailers 


Motorcycles 


Applicable SAE standards or rec- 


Column 1 


Column 2 


Column 3 


Column 4 


Column 5 


Headlamps 


SeeSV 






[For motorcycles only, J584, April 
1964. J566, January I960.] 


Taillamps^ 


2 red 


2 red 


1 red 


J585e, September 1977. 


Stoplamps 


2 red 


2 red 


1 red 


SAE J586. February 1984. 


High mounted stoplamp 


1 red. for passenger cars 
only 


Not required 


Not required 


J 186a. September 1977. 


License plate lamp ' 


1 white 


1 white 


1 white 


J587. October 1981. 


Parking lamps - 


2 amber or white 


None 


None 


J222, December 1970. 


Reflex reflectors 


4 red, 2 amber 


4 red; 2 amber 


3 red; 2 amber 


J594f, January 1977. 


Intermediate side reflex 
reflectors ^ 


2 amber 


2 amber 


None 


J594f. January 1977. 


Intermediate side marker 
lamps ' 


2 amber 


2 amber 


None 


J592e. July 1972. 


Side marker lamps 


2 red, 2 amber 


2 red; 2 amber 


None 


J592e, July 1972. 


Backup lamp 


1 white 


None 


None 


J593C, February 1968. 


Turn signal lamps ' 


2 red or amber: 2 amber 


2 red or amber 


2 amber; 2 red or 
amber 


SAE J588. November 1984. 


Turn signal operating 


1 


None 


' 


J589. April 1964. 


Turn signal flasher 


1 


None 


1 


J590b. October 1965. 


Vehicular hazard warn- 
ing signal operating 
unit 


1 


None 


None 


J910, January 1966. 


Vehicular hazard warn- 
ing signal flasher 


1 


None 


None 


J945, February 1966. 



[(56 F.R. 12123— March 22,1991. Effective: March 22, 1991)] 
■SeeSS.l.l.lO. -See S5.1.I.1 1-12. 'See S5.5.6. •'See S5.1 



(Rev. 3/22/91) 



PART 571; S 108-32 



Table IV. — Location of Required Equipment All Passenger Cars and Motorcycles, and Multipurpose 
Passenger Vehicles, Trucks, Trailers, and Buses of Less Than 80 Inches Overall Width 



Molorcycle 



Headlamps 



On the front, each headlamp provid- 
ing the upper beam, at the same 
height. 1 on each side of the verti- 
cal centerline. each headlamp pro- 
viding the lower beam, at the same 
height, 1 on each side of the verti- 
cal centerline, as far apart as prac- 
ticable. See also S7. 



On the front, on the vertical center- 
line, except that if two are used 
they shall be symetrically disposed 
about the vertical centerline. 



Not less than 22 inches (55.9 cm) nor 
more than 54 inches (137.2 cm). 



On the rear — I on each side of the On the rear — on the vertical center- 
vertical centerline, at the same line except that if two are used, 
height, and as far apart as prac- they shall be symmetrically dis- 
ticable -. posed about the vertical centerline. 



Not less than 15 inches. 
than 72 inches. 



On the rear — on each side of the ver- 
tical centerline, at the same height, 
and as far apart as practicable -. 



On the rear — on the vertical center- 
line except that if two are used, 
they shall be symmetrically dis- 
posed about the vertical centerline. 



ot less than 15 inches, nor more 
than 72 inches. 



High-mounted One the rear, on the vertical center- Not required 

stoplamp line [See S5. 1.1.27, S5.3.1.8, and 

Table III], effective September I, 
1985. for passenger cars only. 



See S5.3.1.8 for passenger cars. Not 
less than 34 inches for multipur- 
pose passenger vehicles, trucks, 
and buses. 



License-plate lamp At rear license plate, to illuminate the At rear license pla 

plate from the top or sides. 



No requirement. 



On the front — 1 on each side of the Not required 
vertical centerline. at the same 
height and as far apart as prac- 



Reflex reflectors 



On the rear — 1 red on each side of On the rear- 



red on the vertical Not less than 15 inches, nor more 



the vertical centerline, at the same 
height, and as far apart as prac- 
ticable -. 
On each side — 1 red as far to the rear 
as practicable, and 1 amber as far 
to the front as practicable -. 



centerline except that, if two are than 60 inches, 
used on the rear, they shall be 
symmetrically disposed about the 
vertical centerline. 
On each side — 1 red as far to the rear 
as practicable, and 1 amber as far 
to the front as practicable. 



On the rear 



Not required 



No requirement. 



Turn-signal lamps ' 



At or near the front — 1 amber on 
each side of the vertical centerline, 
at the same height, and as far apart 
as practicable. 

On the rear — 1 red or amber on each 
side of the vertical centerline, at 
the same height, and as far apart as 
practicable. 



At or near the front — 1 amber on 
each side of the vertical centerline 
at the same height, and having a 
minimum horizontal separation dis- 
tance (centerline of lamps) of 16 
inches. Minimum edge to edge 
separation distance between lamp 
and headlamp is 4 inches. 

At or near the rear — 1 red or amber 
on each side of the vertical center- 
line, at the same height and having 
a minimum horizontal separation 
distance (centerline to centerline of 
lamps) of 9 inches. Minimum edge 
to edge separation distance be- 
tween lamp and tail or stop lamp is 
4 inches. 



Side marker lamps On each side — 1 red as far to the rear Not required 

as practicable, and 1 amber as far 
to the front as practicable. 



Not less than 15 inches. 



Intermediate side 
marker lamps 



On each side — 1 amber located at or Not required 
near the midpoint between the 
front and rear side market lamps. 



Not less than 15 inches 



Intermediate side 
marker reflectors 



On each side — 1 amber located at or Not required 
near the midpoint between the 
front and rear side marker reflec- 



PART571; S 108-33 



(Rev. 12/10/92) 



Note: (1) The term "overall width" refers to 
the nominal design dimension of the widest part 
of the vehicle, exclusive of signal lamps, marker 
lamps, outside rearview minors, flexible fender 
extensions, and mud flaps, determine with doors 
and windows closed, and the wheels in the 
straight-ahead position. 

This supersedes the interpretation of the term 
"overall width" appearing in the Federal Reg- 
ister on March 1, 1967 {32 FR 3390). 

(2) Paragraph S3.1 and Tables I and III of 
§571.108 as amended (32 FR 10833, Dec. 16, 
1967), specify that certain lamp assembles shall 
conform to applicable SAE Standards. Each of 
these basically referenced standards subreferences 
both SAE Standard J575 (tests for motor vehicle 
lighting devices and components) which in turn 
references SAE Standard J573 on bulbs, and SAE 
Standard J567 on bulb sockets. 



(3) Paragraph C of SAE Standard 575 states in 
part: "Where special bulbs are specified, they 
should be submitted with the devices and the 
same or similar bulbs used in the tests and oper- 
ated at their rated mean spherical candlepower." 
The Administrator has determined that this provi- 
sion of SAE Standard J575 permits the use of 
special bulbs, including tubular-type bulbs, which 
do not conform to the detailed requirements of 
Table I of SAE Standard J573. It follows that the 
sockets for special bulbs need not conform to the 
detailed requirements of SAE Standard J567. 
These provisions for special bulbs in no way 
except the lamp assemblies from meeting all 
performance requirements specified in Federal 
Standard No. 108, including those specified in the 
basically referenced SAE Standards, and in the 
subreferenced SAE Standard J575. 



f 



(Rev. 12/10/92) 



PART 571; S 108-34 



PREAMBLE TO AN AMENDMENT TO FEDERAL MOTOR VEHICLE SAFETY 

STANDARD NO. 111 

Convex Cross View Mirrors on School Buses 

[Docket No. 89-26; Notice 3] 
RIN 2127-AD24 



ACTION: Final rule. 

SUMMARY: This notice amends Federal motor 
vehicle safety standard No. Ill, Rearview Mir- 
rors, with respect to the field-of-view around 
school buses. The notice amends the standard to 
require a bus driver to be able to see, either 
directly or through mirrors, certain specified areas 
in front of and along both sides of school buses; 
to specify certain criteria for convex cross view 
mirrors; and to establish test conditions designed 
to ensure that the image of an object is sufficiently 
clear. The amendments will improve the view 
around stopped school buses, thus reducing the 
risk of school buses striking student pedestrians. 

Effective Date: The amendments become effec- 
tive December 2, 1993. 

1. Background 

School buses provide an extremely safe forni of 
transportation. On a vehicle-mile basis, school 
buses are about four times safer than passenger 
cars. Despite this outstanding safety record, 
injuries and fatalities do occur, with most of them 
occurring to pedestrians outside the school bus. 
According to the May 1989 report by the 
National Academy of Sciences (NAS), "Improv- 
ing School Bus Safety," an average of 38 pedes- 
trians are killed each year in school bus-related 
incidents. Of these 38 pedestrian fatalities, an 
average of 26 result from students being struck by 
their own school bus and 12 result from being 
struck by another vehicle. The NAS report also 
estimated that 283 children suffer mostly minor 
injuries, when they are struck by their own bus. 
The NAS report concluded that since children are 
at greater risk of being killed in school bus load- 
ing zones (i.e., boarding and leaving the bus) than 
on board school buses, "a larger share of the 
school bus safety effort should be directed to 



[improving the safety ot] bus stops and loading 
zones." 

NAS accordingly made two specific rec- 
ommendations to NHTSA. First, to reduce the 
number of students who are struck by vehicles 
illegally passing a stopped school bus, NAS rec- 
ommended the establishment of a Federal motor 
vehicle safety standard requiring the installation 
of stop signal arms on all new school buses. (The 
agency has published Federal motor vehicle safety 
standard 131, "School Bus Pedestrian Safety 
Devices," which becomes effective for all new 
school buses produced on or after September 1, 
1992. 56 FR 20363, May 3, 1991). Second, to 
reduce the number of children who are struck by 
their own school bus, NAS recommended that 
NHTSA "reexamine its standards for cross view 
mirrors to determine whether current specifica- 
tions can be modified to give the driver a better 
view of the areas in front of and immediately 
beside the bus." 

Federal motor vehicle safety standard No. Ill, 
Rearview Mirrors, (49 CFR 571.111) currently 
requires each school bus that is not a forward 
control vehicle, i.e., a transit style bus, to have an 
outside cross view mirror of a specified size and 
shape (S9.2), "mounted so as to provide the 
driver a view of the front bumper and the area in 
front of the bus" (S9.2(b)). The standard also 
requires each school bus to have an outside rear- 
view minor of unit magnification (i.e., flat mir- 
ror) on each side of the bus, to provide the driver 
with a view to the rear along both sides of the 
bus (S9.1). In addition to meeting the require- 
ments in Standard No. Ill, school buses are 
required by nearly every State to be equipped 
with additional mirrors, particularly cross view 
mirrors. 

As noted earlier, an average of 26 students are 
killed each year and 283 are injured each year 
after being struck by their own school bus. These 



PART 571: Slll-PRE-29 



incidents are rare. Nevertheless, the potential for 
such tragedies is actually quite large because 
every time a student gets on or off a school bus, 
there is a chance that the driver may not see that 
student in the proximity of the bus. According to 
the 1989 NAS report, of the 26 students killed as 
pedestrians each year "tv/o-thirds are struck by 
the front of the bus and one-third by the rear of 
the bus, usually the rear wheels." A review of 
specific incidents reveals that the fatalities 
occurred because the driver did not see the child 
in front of or to the side of the bus. In many 
cases in which the child was struck by the bus's 
rear wheels, the bus had already left the bus stop. 
In these cases, the children were typically running 
after the moving bus and fell under the rear 
wheels. Such incidents cannot be totally avoided 
through changes to the mirror requirements, since 
driver error may be a significant cause of many 
such incidents. In addition, once the school bus is 
moving, the driver must focus on other driving 
actions in addition to looking into the mirror sys- 
tems to check for students around the outside of 
the bus. However, to reduce the likelihood of stu- 
dents being struck by their own bus in the school 
bus loading zone, the agency has conducted this 
rulemaking to improve the means available for 
the school bus driver to detect their presence 
around the stopped bus. 

The Kansas Department of Transportation con- 
ducts an annual nationwide "School Bus Loading 
and Unloading Survey" which reviews every 
school bus pedestrian fatality. This study confirms 
that a significant, although decreasing, number of 
pedestrians are killed by school buses. The Kan- 
sas data indicate that the number of pupils killed 
nationwide in school bus loading zones was 45 in 
1985. 42 in 1986, 32 in 1987, 16 in 1988. 17 in 
1989, and 18 in 1990. The agency believes that 
the decrease in the number of school bus loading 
zone fatalities is due to a combination of factors, 
including the use of more and better mirtors, the 
increased use of stop signal arms, and improved 
school bus driver and student training. Despite 
this trend, this type of incident remains the most 
common way students are killed in school bus- 
related incidents. Therefore, the agency has con- 
ducted this rulemaking to upgrade Standard No. 
Ill's mirtor requirements to reduce further the 
potential for fatalities and injuries to students by 
school buses. 



II. Previous Agency Action 
A. Advance Notice of Proposed Rulemaking 



( 



On December 17, 1989, NHTSA published an 
Advance Notice of Proposed Rulemaking 
(ANPRM) announcing the agency's interest in 
measures designed to prevent children from being 
struck by school buses during and after loading 
and unloading operations. 54 FR 53127. The 
ANPRM asked questions about pedestrian safety 
around school buses to assist the agency in decid- 
ing whether to pursue rulemaking on cross view 
mirror systems and other devices designed to pro- 
tect pedestrians from being struck by the school 
bus (e.g., crossing control arms, sensors, or video 
monitors). Among the issues presented were: (1) 
The safety need for amending the mirror require- 
ments or for requiring additional equipment such 
as crossing control arms; (2) the need to develop 
performance requirements to ensure that a driver 
sees or is otherwise aware of pedestrians in 
school bus loading zones; (3) the costs of requir- 
ing different types of or additional mirror systems 
and of requiring other types of equipment; and (4) 
the potential impact of new requirements on 
school bus users currently in compliance with 
FMVSS No. Ill and on cuiTent State laws that ^ 

would differ from the Federal requirements that V 

might be proposed. 

The agency received comments from State and 
local governmental organizations, school bus 
manufacturers. miiTor and other equipment manu- 
facturers, associations, and individuals. The com- 
menters generally agreed that measures should be 
taken to reduce the number of children struck by 
school buses and to improve the view of school 
bus drivers around the school bus while it is in 
the school bus loading zone. Commenters also 
addressed other issues raised in the ANPRM, 
including the need for devices other than mirror 
systems for increasing school bus drivers" aware- 
ness of children outside of school buses, the bene- 
fits from training programs, and the costs of the 
equipment addressed in the ANPRM. 

B. Notice of Proposed Rulemaking 

Based on the comments received to the 
ANPRM and the results of NHTSA research con- 
ducted by the Vehicle Research and Test Center 
(VRTC) on school bus miiTor performance ^ 
("Ergonomic Research on School Bus Cross f 
View Mirror Systems" DOT-HS-807-676, ^- 



PARI 571; SIll-PRE-30 



August 1990), the agency published a Notice of 
^ Proposed Rulemaking (NPRM) in the Federal 
A Register. 56 FR 20171. May 2, 1991. The 
^^ agency had two primary objectives in publishing 
the NPRM: (1) To improve the capability of 
school bus drivers to see specified critical areas 
in front of and alongside of school buses in 
school bus loading zones, and (2) to propose a 
performance-oriented standard that would replace 
the existing requirements that prevented certain 
new convex cross view mirror designs. The 
NPRM proposed specific performance require- 
ments to Standard No. 1 1 1 to ensure that a seated 
school bus driver could see, either directly or 
through mirrors, certain specified areas in front of 
and alongside of a school bus. The proposal 
specified certain criteria for convex cross view 
mirrors and proposed establishing test conditions 
to ensure that the image of an object in a mirror 
had sufficient clarity. The NPRM also announced 
the agency's decision not to proceed further with 
rulemaking to require school buses to be equipped 
with other devices such as crossing control arms, 
sensors, or video monitors. 
The agency received comments in response to 
^ the NPRM from State and local organizations, 
^ school bus manufacturers, equipment manufactur- 
ers and suppliers, associations, and other 
organizations. The commenters generally sup- 
ported the proposal but provided suggested modi- 
fications to various portions of it. The agency has 
considered all the comments in developing the 
final rule. The commenters' significant points are 
addressed below, along with the agency's 
response. 

III. Agency Decision 

A. General Considerations 

Based on the docket comments and other avail- 
able information, NHTSA has decided to amend 
Standard No. 1 1 1 with respect to the field-of-view 
around school buses. This final rule amends the 
standard to require a bus driver to be able to see, 
either directly or through mirrors, certain speci- 
fied areas in front of and along both sides of 
school buses; to specify certain criteria for convex 
cross view mirrors; and to establish test condi- 
tions designed to ensure that the image of an 
\ object is sufficiently clear. Standard No. 1 1 1 is 

^ also amended to include detailed test procedures 

to ensure that a school bus provides adequate 



field-of-view around a stopped school bus, thus 
reducing the risk of school buses striking student 
pedestrians. 

Among the issues addressed in this notice are 
the field-of-view performance requirements; the 
placement and characteristics of cylinders rep- 
resenting the field-of-view requirements; school 
bus mirror systems including both flat driving 
mirrors and convex cross view mirrors; specific 
concerns about convex cross view mirrors includ- 
ing accommodation distance, discontinuities in the 
surface's slope, adjustment, image quality, and 
labeling information about their proper use; test- 
ing procedures; and the rulemaking's anticipated 
costs and effective date. 

While the final rule essentially adopts the 
provisions proposed in the NPRM, the final rule 
does contain several changes as compared to the 
proposal. Among the more important changes are 
that the field-of-view requirements include the 
area near the rear left side of the bus, that the test 
procedure specifies the stop signal arm be in the 
retracted position and the front entry door be 
closed during the testing, that determining the 
minimum radius of curvature of a mirror be based 
solely on the distance from the driver's eye loca- 
tion to the mirror surface, that the message about 
the convex mirror be placed inside the vehicle 
and be expanded to be more informative, and that 
testing is allowed at any point within a specified 
area forward of the 25th percentile adult female 
driver's eye location, instead of four specific 
points relative to the eye location. 

B. Field-of-view requirements 

As explained above. Standard No. 1 1 1 cur- 
rently specifies that each school bus must have an 
outside rearview mirror of unit magnification (i.e., 
a flat mirror) on both sides of the bus that "pro- 
vides the driver a view to the rear along both 
sides of the vehicle * * *" In addition, each 
school bus, except for forward control vehicles, 
must have one convex cross view mirror that 
complies with detailed specifications and 
"provide(s) the driver a view of the front bumper 
and the area in front of the bus." 

The NPRM proposed requiring that a school 
bus driver be able to see, directly or through mir- 
rors, test cylinders representing smdents in critical 
areas around the school bus. To effectuate this 
goal, each school bus would be required to have 
mirror systems on both the left and right sides of 



PART 571: Slll-PRE-31 



the school bus — a set of driving mirrors to view 
the sides of the bus and areas to the rear of the 
bus, and a set of convex cross view mirrors to see 
specified areas at the left front comer of the bus, 
in front of the bus, and along the right side of the 
bus. Areas viewable along the bus's right side via 
the two mirror systems would be required to 
overlap, as would the areas visible along the bus's 
left side. Along each side, the driver would be 
provided with a view of the ground from the front 
bumper forward, along the sides of the bus, and 
extending at least 200 feet rearward from the mir- 
ror. The NPRM proposed that the driver must be 
able to see the entire top surface of the cylinders 
placed at critical locations around the bus. Com- 
pared to the current requirements for school bus 
mirrors, the proposed field-of-view requirements 
would extend the areas which must be visible, 
provide field-of-view requirements applicable to 
any school bus configuration, and provide greater 
objectivity. The NPRM asked whether the pro- 
posed field-of-view requirements, as expressed 
through the placement of cylinders, would reason- 
ably represent the locations at which school bus 
pedestrians need to be seen by the driver during 
school bus loading and unloading. 

With respect to the field-of-view approach, the 
commenters, including the National School 
Transportation Association (NSTA), Transport 
Canada, Mirror Lite, Arizona DOT (Arizona), and 
the Washington State Superintendent of Public 
Instruction (Washington State) believed that this 
approach was appropriate. No commenter opposed 
the proposed approach. Washington State com- 
mented that the proposal would provide a realistic 
performance standard for mirrors. Transport Can- 
ada believed that there was a need to improve the 
field-of-view for school bus drivers and to pro- 
vide an objective measurement method for all 
mirrors on school buses. 

After reviewing the comments, NHTSA con- 
cludes that establishing performance-based field- 
of-view requirements for school bus mirror sys- 
tems is reasonable and appropriate. Such an 
approach will reduce the risk of injury to student 
pedestrians, while affording mirror and school bus 
manufacturers and users greater flexibility. 



C. Test Cylinders 
1 . Cylinder Placement £ 

As for the placement of test cylinders used to 
represent student pedestrians, the NPRM proposed 
that they be located at specified locations near the 
bus's front wheels, front bumper, locations for- 
ward of the bus, near the front right and left 
wheels, and near the rear right wheel. These pro- 
posed locations were based on narratives in the 
NAS report and docket comments, the VRTC 
report, the State of Ohio's regulation, and the 
Eleventh National Conference of School 
Transportation. Nevertheless, unlike Ohio's regu- 
lation and the Eleventh National Conference's 
specification, NHTSA proposed specific locations 
and test procedures for showing compliance with 
the requirements. In requesting comments about 
whether the proposal reasonably represented loca- 
tions where student pedestrians are struck by 
school buses, the agency expressly asked whether 
the area near the left rear wheels poses a safety 
problem. 

While commenters generally supported the pro- 
posed locations for the test cylinders, some com- 
menters addressed whether cylinders should be L 
placed at certain additional locations around the V^ 
school bus. 

Several commenters, including the National 
PTA, Blue Bird, Mirror Lite, the West Virginia 
Department of Education (West Virginia), NSTA, 
Washington State, and Arizona, stated that a view 
down the left side of the bus was important. No 
commenter stated that a view of the left side of 
the bus was unnecessary. Mirror Lite cited fatali- 
ties in Michigan and Texas to support the view 
that incidents along the bus's left side, although 
uncommon, do occur. In recommending that the 
field-of-view be the same for both sides of the 
bus. Mirror Lite commented that the cost of such 
a requirement would be the same and that drivers 
prefer mirrors to be matching on the right and 
left, rather than having two different fields-of- 
view. 

After reviewing the comments, NHTSA has 
concluded that the field-of-view on the left side 
of the bus should be extended back to the ground 
near the left rear wheel. While the agency 



PART 571- Slll-PRE-32 



acknowledges that children are infrequently struck 
^ near the left side of the bus, the agency notes that 
B such incidents do occur. Accordingly, by requir- 
^ ing test cylinders to be placed by the left rear tire, 
the amendments will increase the likelihood that 
the new school bus mirror requirements can pre- 
vent these incidents as well. 

The agency conducted mirror evaluations on 
both conventional and transit-style school buses 
indicating that left side mirror systems designed 
to meet the proposed field-of-view requirements 
for the left front comer and the front of the 
school bus would also be able to provide a view 
of test cylinders located at least six feet to the left 
of the left rear wheel without any adjustments to 
the mirrors. Additionally, based on the agency's 
review of current mirror systems, the agency 
anticipates that the mirrors on the left and right 
side of the bus will be symmetrical (i.e., a mirror 
designed to view the right side of the bus will 
also be able to view the left side of the bus when 
mounted on the left front of the bus). Based on 
the above, the agency has modified the final 
requirements to include additional test cylinders 
located one foot and six feet to the left of the left 
^ rear axle. 

^ Although a cylinder located twelve feet to the 

right of the rear axle on the bus' right side is 
required to be visible, NHTSA believes that is not 
necessary to require that a test cylinder located 
twelve feet to the left of the rear axle be visible. 
For a school bus on the side of the road in a load- 
ing zone, a cylinder located twelve feet to the left 
of the left side of the bus would represent a stu- 
dent standing a full traffic lane from the bus. The 
agency believes that it is unlikely that a student 
would be in such a position when the school bus 
starts to depart from the loading zone. In local- 
ities where school buses stop in a traffic lane, a 
cylinder located twelve feet from the left side 
would represent a child on the other side of the 
street on a two lane street. 

During the course of its mirror evaluations, the 
agency observed that, in some cases, the cylinders 
at the left rear axle of the school bus were either 
partially or fully blocked from view by the 
extended stop signal arm. Visibility depended on 
the bus body type and the location of the stop sig- 
nal and the left side cross view mirror. In con- 
k trast, the test cylinders were visible when the stop 

' arm was retracted. The agency also noted that the 

test cylinders at the right rear axle were either 



partially or fully blocked by the door when an 
outward-opening front entry door was open. 
Based on these observations, NHTSA has decided 
that the test procedure will specify that the stop 
signal arm be in the retracted position and the 
front entry door be closed. This procedure recog- 
nizes that school bus drivers must close the door, 
which retracts the stop signal arm, and then view 
the mirrors to ensure that no students are in dan- 
ger around the bus before the school bus leaves 
the loading zone. If the driver attempted to view 
the areas around the bus before closing the door 
and retracting the stop signal arm, the stop signal 
arm would also block the driver's view of the 
road, thus impairing many driving decisions. 

Blue Bird commented that placing test cyl- 
inders J, K, and L on a plane one foot away from 
the bus would be more appropriate than the pro- 
posed two foot distance because the two foot 
location of cylinder L would provide only limited 
visibility adjacent to the rear wheel. (The agency 
notes that cylinder L in the NPRM is cylinder N 
in the final rule.) Blue Bird commented further 
that a one foot distance from the most outboard 
edge of the front bumper for cylinders J and K 
would help ensure adequate visibility near the 
front wheels. The agency agrees with this com- 
ment and has revised the location requirements 
accordingly. 

Blue Bird commented that there were no pro- 
posed requirements for the visibility of cylinder 
M. which is located six feet from the right side 
of the bus at the rear wheel. (The agency notes 
that cylinder M in the NPRM is cylinder O in the 
final rule.) That was an oversight in the NPRM, 
and a provision about cylinder M is included in 
the final rule's requirements for mirror System B. 

NSTA suggested that a test cylinder be added 
to the area directly to the rear of the service door. 
After conducting mirror evaluations, the agency 
has concluded that locating a test cylinder to the 
rear of the service entry door would not be nec- 
essary since mirror systems that provide a view of 
cylinders K and L would also provide a view of 
the rear side of the service entry door. 

Transport Canada believed that because it is 
theoretically possible for blind spots to exist in 
some areas between cylinders in front of the bus, 
NHTSA should specify areas whose perimeters 
would be defined in terms of cylinder locations 
that must be seen, rather than simply the cylinders 
themselves. In the course of this rulemaking. 



PART 571; SIll-PRE-33 



agency staff have evaluated a variety of mirror 
systems on both conventional and transit-style 
school buses. In all cases where the test cylinders 
could be seen and identified in a mirror system, 
the full ground areas around and between the cyl- 
inders could be seen. The agency notes that while 
a blind spot could occur when looking at a single 
mirror, such blind spots were eliminated when 
viewing the entire mirror system. Although it 
might be theoretically possible for a blind spot to 
exist between test cylinders, the agency believes 
such situations would be extremely rare. 

The New York State Senate Committee on 
Transportation (New York) believed that the 
requirements in S9.2 for the System A driving 
mirrors on the right side of the bus should have 
a field-of-view that extends twelve feet out from 
the side of the bus, not just two feet out, to pro- 
vide the driver with adequate warning time that a 
pedestrian contact is imminent. The agency notes 
that the requirements in S9.2 are primarily for the 
driving mirror system which must include at least 
one mirror of unit magnification. Such a mirror 
could not be adjusted to provide a view that 
included the side of the bus and a point twelve 
feet out from the rear axle line unless it were 
unusually large in size. Yet, such a large mirror 
would create its own large blind spot. The 
requirements for System B convex cross view 
mirrors, which are pedestrian detection mirrors, 
already provide the seated driver with information 
about individuals that may be as close as twelve 
feet from the side of the school bus. Accordingly, 
because the mirror that would be necessary to 
accommodate New York's request would have 
safety trade-offs and provide redundant perform- 
ance, NHTSA has decided not to change the pro- 
posed requirements for S9.2 in this rule. 

2. Cylinder Dimensions 

The proposed provisions about the test cyl- 
inders used to represent student pedestrians 
specify that they be one foot high and one foot 
in diameter and require that their entire top sur- 
face be visible. The agency based this proposal on 
the VRTC report's recommendation that measure- 
ments be made near ground level and on accounts 
in the docket explaining that children struck by 
school buses were low to the ground. Addition- 
ally, nairatives in the 1989 NAS report and the 
mirror requirements from Ohio support the con- 
cept of using some sort of three-dimensional rep- 



resentation of a small child. An exception to the 
one foot requirement would be that the cylinder 
placed twelve feet to the right of the rear right M 
wheel, would be three feet high and one foot in ^ 
diameter. The agency believed that this cylinder 
needed to have such dimensions to evaluate elon- 
gation. 

Several commenters, including NSTA, Mirror 
Lite, and Thomas Built, supported the proposal to 
require the driver to view the cylinder's entire 
top. NSTA commented that this requirement 
would help ensure that the driver is provided with 
a complete enough image to enable the driver to 
identify student pedestrians in the mirror. After 
evaluating new generation mirrors and some older 
mirrors which they consider to be "marginal," 
Thomas Built determined that only the new mir- 
rors could meet the cylinder viewing require- 
ments. This led Thomas Built to conclude that 
viewing the top of the cylinders is a satisfactory 
requirement. 

A few commenters were concerned that the 
proposed test cylinder was not adequate for ensur- 
ing that all of the critical areas of the ground 
would be visible. Washington State believed that 
by focusing on the cylinder's top, the proposed - 
visibility test may be inadequate because it T^ 
ignores contact at the ground level. Lo-Mar and 
Blue Bird believed that the view of the ground is 
not ensured through the use of one foot high cyl- 
inders. Accordingly, these commenters rec- 
ommended that cylinders be replaced with one 
foot diameter flat discs. 

After considering the comments about test 
object's dimensions, NHTSA has concluded that 
one foot tall cylinders better represent real-world 
situations than flat discs. In the majority of load- 
ing zone incidents, children struck and killed by 
school buses were either standing or bending 
over, according to the Kansas Department of 
Transportation's "1989 School Bus Loading & 
Unloading Survey." Therefore, the agency 
believes that most students who are struck by a 
school bus are at least one foot above the ground. 
Even children who have fallen are above ground 
level because their body thickness at their head or 
torso is at least six inches. If children have fallen, 
the agency expects that they will be attempting to 
get back up. which also adds height. The agen- 
cy's mirror system evaluations further indicate . 



that a three dimensional object such as the one 
foot tall test cylinder more accurately represents 



PART 571; SlII-PRE-34 



real-world situations than a flat disc. In addition, 
the cylinder facilitates testing by providing a 
^ more practicable means for demonstrating the 
W ability of mirrors to view areas around the outside 
of the bus. The three dimensional cylinder also 
makes the relative image quality easier to 
ascertain. 

Mirror Lite commented that the cylinders 
should be of a readily available design to facili- 
tate testing and to avoid discouraging manufactur- 
ers from conducting the test. This view led Mirror 
Lite to recommend using bright orange 18" traf- 
fic cones. Washington State requested that along 
with establishing a requirement for the manufac- 
ture of new buses and equipment, the standard 
should also provide an ongoing performance 
standard for the end user (e.g., mechanics and bus 
drivers). Similarly, Ann Arundel County (Mary- 
land) Public Schools explained that they were 
interested in incorporating the test cylinder grid 
into its training program. 

As for Mirror Lite's comment about an 18" 
traffic cone, NHTSA believes that such a device 
is too tall to represent a child who may be bend- 
ing over or has fallen down. The agency never- 
^ theless agrees with Mirror Lite that having a read- 
W ily available test object will assist States and local 
school districts in evaluating mirrors and training 
school bus drivers. The agency believes that the 
one foot cylinder is a reasonable size and shape 
that should be easy to obtain or fabricate. The 
agency also notes that the one foot test cylinder 
is only required for compliance test purposes, and 
that anyone desiring to build a test lane can sub- 
stitute another test object when conducting 
evaluations or training. 

While generally supporting the performance 
requirements for mirror System B, Blue Bird rec- 
ommended an alternative requirement which 
defined the bounds of specific geometric areas on 
the ground outside the school bus which would 
have to be seen. Among Blue Bird's criticisms of 
the proposal were the use of a cylinder rather 
than a disc, the need to reduce the distance 
between the test cylinders and the bus to one foot, 
the need to include cylinder M in the performance 
requirements, and the need to include visibility 
requirements for the left side of the bus. Since all 
of these items have been addressed above and all 
k but the use of a disc were adopted, the agency 
" does not believe Blue Bird's recommended alter- 
native is necessary. 



3. Cylinder Color 

The NPRM proposed that the test cylinders 
be a color which provides a high contrast with the 
surface on which the bus is parked. According to 
the VRTC report, such a contrast would facilitate 
compliance testing. While the proposal did not 
specify a particular color, the agency requested 
comments about what color would provide a high 
contrast with the ground and whether a given 
color should be specified. 

Several commenters addressed the appropriate 
color and design of the test objects. NSTA sug- 
gested that rather than having a high contrast 
color, the cylinder should be a color that blends 
into the surroundings, believing that visibility 
becomes a problem when a child blends in with 
the surroundings (e.g., the bus itself, pavement). 
New York favored replacing the cylinders with 
two dimensional cutouts of children and adults 
with colors that are representative of clothes typi- 
cally used by school children or adults. 

Other commenters believed that the test cyl- 
inder should be a bright color. Mirror Lite rec- 
ommended using bright orange traffic cones. 
Thomas Built explained that its mirror tests are 
conducted using bright colored cylinders, e.g., 
safety orange sides with lime green tops and 
black letters. R&R Research recommended that to 
make the test procedure less vague, the color of 
the test cylinders should "be specified either 
quantitatively (i.e., the percent contrast) or quali- 
tatively by specifying the color of the cylinders." 

After reviewing the comments and its own mir- 
ror evaluations, NHTSA has decided that the test 
cylinder must provide a high contrast with the 
surface on which the bus is parked. The agency 
believes that having such a high contrast will 
facilitate compliance testing. Nevertheless, the 
agency has determined that it would be inappro- 
priate and unnecessary to specify a given color 
for the test cylinder. The agency has no informa- 
tion to suggest that one color would be more 
appropriate for a test cylinder than any other 
color. The agency believes that specifying a sin- 
gle color would complicate the standard without 
providing any significant corresponding benefits. 

D. School Bus Mirror Systems 

1. General 

Standard No. 1 1 1 currently requires school 
buses to be equipped with two types of mirror 



PART 571; Slll-PRE-35 



systems: (1) An outside rearview mirror of unit 
magnification ("flat mirror") of not less than 50 
square inches of reflective surface on each side of 
the bus; and (2) one convex cross view mirror. In 
practice, buses are equipped with a flat driving 
mirror on each side of the bus, two or more con- 
vex cross view mirrors, and typically at least one 
supplemental convex mirror mounted near each 
flat mirror and designed to serve as an additional 
driving mirror. Convex driving mirrors are typi- 
cally about four inches in diameter and have a 
radius of curvature (ROC) greater than 35 inches. 
These larger radii of curvature mirrors have much 
greater image clarity than the convex cross view 
mirrors mounted on the front of the bus and 
therefore can safely be used as driving mirrors. 
All mirror systems are used by drivers to see stu- 
dents in the loading zone around buses, although 
the flat miiTors and the supplemental convex driv- 
ing mirrors are primarily designed to serve as 
driving mirrors. 

The NPRM proposed to modify the current 
requirements for both types of mirror systems so 
that each school bus would be equipped with two 
mirror systems on each side of the bus: (1) A sys- 
tem that includes flat driving mirrors of unit mag- 
nification and optional convex driving mirrors 
(designated as "System A") and (2) a system 
that consists of convex cross view mirrors for stu- 
dent detection during loading and unloading (des- 
ignated as "System B"). The areas viewable 
along both sides of the bus via the two mirror 
systems would be required to overlap on each 
side, providing the driver with a view of the 
ground in front of and along both sides of the bus 
and extending at least 200 feet rearward from the 
driving mirror. Because the agency recognized 
that most current driving mirror systems on 
school buses consist of both a flat mirror and a 
convex mirror, the NPRM included language that 
"one or more mirrors" could be used to meet the 
requirements of S9.2 for System A mirrors. 

2. Driving Mirrors — System A Mirrors 

As for System A mirrors, the NPRM proposed 
making the current requirements for such mirror 
systems more objective and expanding the field- 
of-view to include a larger area. Specifically, the 
NPRM proposed amending section S9.2 to require 
that the driver have a view at least 200 feet to the 
rear and at least two feet to the right of the right 
side of the bus. The NPRM explained that the 



proposed requirements reflect the findings of the 
1 1 th National Conference on School Transpor- 
tation and accounts in the NAS report and docket 
that a significant number of incidents occur by 
the right rear wheels of school buses. 

In responding to the NPRM's proposal about 
System A mirror systems, several commenters, 
including Mirror Lite, Thomas Built, Transport 
Canada, and Blue Bird, appear to have misunder- 
stood the proposed requirements of S9.2. Based 
on their comments, it appears that they believe 
the system's flat mirror portion by itself would 
have to comply with the requirement that the 
view of the "area of the ground which extends 
rearward from the mirror surface [must be] not 
less than 200 feet." The agency wishes to clarify 
that the flat mirror by itself need not comply with 
S9.2. The proposed requirements were for a 
"mirror system" (emphasis added) which could 
include both a flat mirror and a convex mirror. 
Accordingly, to comply with S9.2, it is permis- 
sible for the convex portion of the mirror system 
to provide some portions of the required field-of- 
view. 

The agency believes that it is unnecessary to 
expressly require the installation of a convex mir- 
ror for the driving mirror system. Since the pro- 
posed revisions to Standard No. 1 1 1 are perform- 
ance-oriented, not design-oriented, manufacturers 
can choose whatever mirror system they believe 
is best. Avoiding unnecessary restrictions facili- 
tates the introduction of future technological 
improvements in mirror systems. 

Blue Bird suggested modifying S9.2(c) by 
establishing specified zones along both sides of 
the bus which would have to be viewable to the 
seated driver. As explained in the section on test 
cylinders, the agency believes that establishing 
field-of-view requirements through test cylinders 
at specific locations around a school bus provides 
a more realistic simulation of real-worid school 
bus operations than establishing geometric zones. 

Blue Bird also commented that establishing 
minimum permissible radii for convex mirrors 
used in proposed mirror System A could be det- 
rimental to the performance requirements being 
proposed. The agency notes that neither the 
NPRM nor the final rule included provisions 
about minimum radii of curvature for System A 
mirrors. The same is true for System B mirrors. 



PART 571; Slll-PRE-36 



3. Convex cross view minors — System B Mirrors 

a. General. S9.2(a) of Standard No. Ill cur- 
rently contains detailed specifications about the 
characteristics of convex cross view mirrors, 
including minimum and maximum permissible 
radii of curvature, minimum surface areas, and 
restrictions for convex mirrors with non-uniform 
radii. The current standard only requires one con- 
vex cross view mirror. 

The NPRM proposed that a cross view mirror 
system (System B) be provided on both sides of 
a school bus to ensure that seated drivers have a 
complete view of all critical areas in front of and 
along both sides of the bus that are not within 
their direct field-of-view. The NPRM also 
included a requirement that "[T]he view of the 
ground provided at the driver's eye location by 
system B shall overlap with the view of the 
ground provided by system A." The agency pro- 
posed to delete the current specifications for con- 
vex mirrors, believing that this action would per- 
mit States and local school districts to use a wider 
variety of mirrors. 

The NPRM addressed several subissues about 
convex cross view mirror characteristics, includ- 
ing accommodation distance (i.e., the distance at 
which people can focus on images in mirrors), 
discontinuities in the mirror surface's slope, 
adjustment, informational labeling, and image 
quality. 

In addition to general questions about convex 
cross view mirrors, the agency specifically asked 
about whether a minimum permissible radius of 
curvature should be specified, whether convex 
cross view mirrors should be used for driving 
purposes, and whether the upper portion of con- 
vex mirrors should be cut off or blackened out to 
reduce the amount of glare reflected into the driv- 
er's eye. 

All commenters supported using convex cross 
view mirrors to view areas outside of school 
buses. Commenters also addressed specific points 
about particular mirror systems. Mirror Lite 
believed that wide-angle cross view mirrors are 
better than multiple conventional mirrors because 
having multiple mirrors would result in confusion 
as to which mirror is showing what image. 

Several commenters, including Thomas Built 
and Blue Bird, stated that in practice, convex 
cross view mirrors are used for driving purposes. 
Thomas Built and Blue Bird commented that cer- 



tain convex cross view mirrors should not be used 
as driving mirrors. These comments are addressed 
later in this preamble in the section discussing an 
instructional message for the proper use of con- 
vex cross view mirrors. 

Several commenters responded to the agency's 
question in the NPRM about cutting off or black- 
ening out the cross view mirror's upper portion. 
The Arizona DOT opposed cutting off or blacken- 
ing out any portion of the convex cross view mir- 
ror, believing that all portions of the mirror pro- 
vide some benefit if properly adjusted and used. 
In contrast, Washington State, the Tennessee 
DOE, Florida, the Sloan Company, and Mirror 
Lite believed that the top portions of convex cross 
view mirrors serve no useful purpose and should 
be eliminated. Mirror Lite stated that the "market 
place has determined the upper portion of the 
mirror is of no value and may be a distraction to 
the driver." 

Notwithstanding the comments favoring the 
elimination of the top portion of convex cross 
view mirrors, NHTSA believes that there is no 
conclusive information to support this approach. 
Additionally, there is no information available for 
determining what specific areas of mirrors should 
be cut off or blackened out. This type of require- 
ment would also make the standard more design 
restrictive than the agency believes is desirable. In 
addition. Mirror Lite's claim that the "market- 
place" has determined the need for blackening 
out such mirrors does not appear to be accurate, 
since several convex mirrors without blacked-out 
areas are apparently being successfully sold in the 
marketplace. However, if certain mirror areas are 
found to be inefficient, then the agency antici- 
pates that the marketplace will make judgments 
on the efficacy of various mirror systems and that 
those judgments will be reflected in future mirror 
designs. Since no information was produced to 
suggest that the upper portions of cross view mir- 
rors were dangerous to a driver's view of pedes- 
trians, the agency has decided not to establish 
limitations on the field-of-view coverage provided 
by a cross view mirror. The agency believes that 
individual State and local school districts are 
capable of evaluating mirror systems that meet 
these standards and selecting those which best 
meet their needs, including, if they so chose, mir- 
rors from which the top portions have been elimi- 
nated. 



PART571;Slll-PRE-37 



b. Accommodation distances. The NPRM pro- 
posed a new provision that would require that the 
distance from the center of each convex cross 
view mirror to the center point of the driver's eye 
location, plus one-half the smallest radius of cur- 
vamre of the mirror surface be at least 39 inches. 
The agency based this proposal on the VRTC 
report's finding about accommodation distances, 
i.e., the finding that older people have greater dif- 
ficulty focusing on nearby objects, especially in 
convex mirrors with small radii of curvature. 
According to the VRTC report, if the distance 
between the driver and the image in the mirror is 
less than 40 inches, drivers over 40 years old may 
see a blurred image. 

Several commenters supported the 39 inch 
accommodation distance, believing that such a 
requirement is feasible. Thomas Built, R & R 
Research, and Mirror Lite stated that the 39 inch 
distance between the driver seat to the mirror is 
acceptable for most currently-produced buses. 
Nevertheless, R & R Research, along with NSTA, 
questioned whether transit type school buses 
could be equipped to comply with the 39 inch 
requirement. Neither NSTA nor R & R Research 
provided any specific information to support their 
concerns about transit buses. 

Blue Bird disagreed with the 39 inch require- 
ment, stating that it would be difficult to measure 
accurately and might hinder mirror performance 
and innovations. Blue Bird opposed having 
restrictions on the mirror's location, claiming that 
the agency does not restrict the locations of other 
bus components such as gauges, switches, and 
lights. 

Based on the available information, including 
the agency's evaluations of the comments and 
various mirror systems, NHTSA has decided to 
adopt the proposed accommodation distance 
requirement with certain modifications. In 
evaluating various mirror systems on both 
conventional and transit-style school buses, 
NHTSA has found that these mirrors are always 
capable of complying with the proposed 39 inch 
requirement of S9.3(b)(2) when mounted at loca- 
tions consistent with the mirror manufacturers' 
recommendation. The agency also notes that the 
concerns expressed by NHTSA and R&R 
Research about transit-style school buses not 
being able to meet such a requirement were not 
shared by the school bus and mirror manufactur- 
ers commenting on this issue, all of whom stated 



that the requirement could be met. Blue Bird did 
not claim that the proposed 39 inch requirement 
could not be met, only that it would be difficult * 
to measure accurately. Also, Blue Bird appears to \ 
disagree with the proposed requirement on a 
philosophical basis, i.e., since NHTSA does not 
establish restrictions on the location of other 
components of the bus used during its operation. 

In evaluating the proposal, NHTSA has meas- 
ured the distances from the driver's eye location 
to the mirror surface on a number of school 
buses, including transit style buses, and has found 
it to be a straight-forward task that gets easier the 
more it is done. The aspect of the measurement 
that required the most effort was establishing the 
line of sight through a window and then measur- 
ing that line. The use of standard tape measures, 
one used to measure the distance from the mirror 
to the window and the other to measure the dis- 
tance from the window to the eye location, 
worked well for establishing the line of sight and 
measuring it. The thickness of the window was 
then added to the measured distances. A more 
elaborate test setup could be established using a 
laser or high intensity light beam to establish the 
line of sight. Based on the agency's experience in ^ 
measuring mirror distances, the degree of B 
accuracy is not that critical since all of the mirror ^— 
distances were well over 39 inches. 

However, NHTSA agrees with the commenters 
that detennining the minimum radius of curvature 
of a mirror may be a difficult and time consum- 
ing task. Accordingly, the agency has modified 
the final requirement so that the eye accommoda- 
tion distance is based solely on the distance from 
the driver's eye location to the mirror surface. 

The proposed requirements in S9. 3(b)(2) have 
been modified to read as follows in this final rule: 
"Each mirror shall be located such that the dis- 
tance from the center point of the eye location of 
a 25th percentile adult female to the center of the 
mirror surface shall be at least 37.5 inches." To 
repeat, the proposed requirement was for the dis- 
tance from the center of each convex cross view 
mirror to the center point of the driver's eye, plus 
one-half the smallest radius of curvature of the 
mirror surface, to be at least 39 inches. While the 
proposal's provision about adding "one-half the 
smallest radius of curvature" to the distance from 
the driver's eye to the center of the mirror is no , 
longer expressly part of the specified measure- \^^ 
ment, the agency derived the 37.5 inch distance 



PART 571; Slll-PRE-38 



in this final rule using the proposed combination 
of distance between the driver's eye and the mir- 
ror and one-half the radius of curvature of the 
mirror. 

The 37.5 inch minimum was derived as fol- 
lows. Of all the minors used in the VRTC report, 
the smallest radius of curvature (and thus the one 
with the poorest image quality) was 3.41 inches. 
Assuming that the design radius of curvature of 
future mirrors would not be less than 3 inches, 
then one-half of that radius of curvature would be 
1.5 inches. Subtracting 1.5 inches from the 39 
inch proposed requirement leaves 37.5 inches. 
The final rule accordingly accounts for accommo- 
dation distances in worst case situations, just as 
the proposal did, but simplifies the calculation. 

NHTSA disagrees with Blue Bird's comment 
that mirror location should not be regulated 
because the location of other components (i.e., 
gauges, switches, and lights) in the bus are not 
regulated. The agency believes that to ensure the 
safety of student pedestrians, the images in school 
bus mirrors, particularly convex mirrors, cannot 
be blurred for any driver. That same level of con- 
cern is not necessary for clearly seeing a gauge 
or switch, since seeing such devices is not as 
critical for student safety as viewing a mirror sys- 
tem. Also the inherent nature of convex mirrors, 
which reduce the size and elongate the image of 
the reflected object, make mirror images more 
difficult to see and use. By contrast, the task of 
identifying gauges and switches is comparatively 
straightforward. 

Arizona DOT commented that school buses 
should be equipped with forward mount driving 
mirrors on the left side, in lieu of the low mount 
driving mirrors currently being used by many dis- 
tricts. Arizona stated that this requirement "is 
needed in order for the mirror to be at least 39" 
from the driver's eye." NHTSA notes that 
Arizona appears to have misinterpreted the provi- 
sion's applicability, because the minimum 
accommodation distance applies only to convex 
crossview (System B) mirrors, not to driving 
(System A) mirrors. Although the Arizona com- 
ment is related to driving mirrors, instead of the 
cross view mirrors, it illustrates that different 
cross view mirror mounting locations may be nec- 
essary on some types of school buses to meet the 
accommodation distance requirement. 

c. Discontiimities in a mirror surface's slope. 
Standard No. 1 1 1 currently prohibits discontinu- 



ities in a mirror surface's slope. The NPRM pro- 
posed retaining this requirement, but redesignating 
h S9.3(b)(3). The proposal explained that 
prohibiting mirror discontinuities would prevent 
mirrors in which the slope or surface of the mir- 
ror was concave, thus protecting against poor 
image clarity. 

All those commenting on this issue, i.e., NSTA, 
Mirror Lite, Thomas Built Buses, and New York 
State, agreed that retaining the current prohibition 
on mirror discontinuities is necessary. Accord- 
ingly, the final rule adopts this provision. 

Mirror Lite suggested that the agency use the 
term "diminishing image" instead of "distor- 
tion" to describe the image quality provided by 
cross view mirrors. It stated that distortion is a 
flaw in the mirror surface that can be found in 
any type of mirror. After reviewing the comment, 
the agency agrees with Mirror Lite and has 
decided to u.se the phrase "image clarity" rather 
than "distortion" in the preamble. Nevertheless, 
the agency notes that this term is not in the regu- 
latory test. 

d. Mirror supports and adjustment. Standard 
No. 1 1 1 currently requires each flat mirror and 
each convex cross view mirror to be installed 
with a stable support. The NPRM proposed that 
each convex cross view mirror "be installed with 
a stable support designed to dampen vibration." 
This requirement is intended to ensure a clear and 
properly focused image by preventing mirrors 
from vibrating unreasonably and by reducing the 
likelihood that mirrors become misaligned. Com- 
ments to the ANPRM explained that such mis- 
alignment reduces a driver's ability to see chil- 
dren in potentially dangerous locations around a 
stopped school bus. 

The NPRM asked the following questions 
about mirror stability: 

( 1 ) Could the requirements be made more 
precise?; 

(2) Is it necessary to require adjustable 
mounting brackets for all types of cross view 
mirrors?; and 

(3) Do non-adjustable brackets reduce the 
amount of vibration of the mirror while driving 
or idling? 

Commenters disagreed about the need for 
requiring mirrors to have stable supports. NSTA 
and Thomas Built believed such requirements 
were not needed, with Thomas Built stating that 
most current mirror mounting systems provide a 



PART571;SlIl-PRE-39 



stable yet easily adjustable mirror system. In con- 
trast, Washington State and Transport Canada 
supported the proposal to require stable supports. 
Transport Canada favored an objective test to 
evaluate the stability of mirror brackets for cross 
view mirrors but had no particular recommenda- 
tions to increase the requirement's precision. 
Washington State supported the proposed regu- 
latory language, agreeing that vibration can 
significantly hami image quality. Nevertheless, 
Washington State suggested that additional lan- 
guage be included stating that if a minor adjust- 
ment mechanism is necessary, it should be 
designed so that vibrations would not misalign the 
mirror. Arizona explained that its draft State mir- 
ror requirements would specify that cross view 
mirrors "shall be easily adjustable but be rigidly 
braced to reduce vibration." 

Commenters discussed the types of mirror 
adjustment mechanisms cunently being used. 
Some minor systems have both adjustable brack- 
ets and mirrors, some only have adjustable mirror 
portions, and others only have adjustable brackets. 
Mirror Lite, Flynn, and Sloan believed that mir- 
rors should be adjustable. Tennessee, Arizona, 
and Blue Bird believed that mirrors should have 
adjustable brackets. Blue Bird commented that 
properly tightened adjustable brackets become 
rigid and thus perfonn the same function as non- 
adjustable brackets. 

After considering the commenters' varying 
views, NHTSA has determined that Standard No. 
Ill's existing requirements for mirror stability 
are appropriate, and they are adopted in this rule. 
The agency recognizes that different mirror manu- 
facturers have developed various types of mount- 
ing brackets and miiTor mountings that employ 
different degrees of adjustability or non- 
adjustability. There is no evidence in the com- 
ments to the docket, or in any of the mirror 
evaluations the agency has conducted, that the 
proposed requirements could be made any more 
precise. NHTSA notes that Standard No. 1 1 1 cur- 
rently requires '"stable support" for both inside 
and outside mirrors on all types of vehicles, not 
just school buses. The agency believes that these 
requirements should be retained for school buses. 
While a more precise requirement is not possible, 
the agency believes it is important to retain a 
requirement for minor stability in the standard as 
a means of highlighting the importance of mirror 
stability to mirror performance. 



One change from the proposal is prompted by 
Transport Canada's comment that the stability 
requirements should also apply to the System A ■ 
minors. As Transport Canada stated. Standard 
No. Ill's existing requirements for school bus 
outside rearview mirrors include "stable sup- 
ports." The agency agrees that the stability 
requirements should continue to apply to System 
A mirrors, and the final rule's requirements have 
been modified accordingly. 

Additionally, NHTSA notes that on April 26. 
1991, it revised Guideline #17 to state "that all 
school buses shall have a system of mirrors that 
conforms to the school bus requirements of 
FMVSS No. 111." (56 FR 19270) While this 
amendment means that the most current require- 
ments in Standard No. Ill are applicable, the 
agency has decided to issue elsewhere in today's 
Federal Register a conforming amendment to clar- 
ify this situation. In particular, the conforming 
amendment deletes the outdated requirements 
referring to the 30 inch rod test in Guideline #17. 

e. Informational label on using cross view mir- 
rors for driving purposes. The NPRM discussed 
the agency's concern about using convex cross 
view mirtors as driving mirrors. These concerns ^ 
were based on the agency's belief that the inher- \ 
ently poor image clarity and image size reduction 
characteristics of highly convex mirrors make 
such mirrors inappropriate for driving purposes. 
In addition, the reaction time is slower for drivers 
using several mirtor systems each with signifi- 
cantly different radii of curvature. Such mirrors 
may not provide the driver with a consistent ref- 
erence point with respect to the location of 
images in the various mirrors. Accordingly, the 
NPRM proposed that mirrors with an average 
radius of curvature less than 35 inches be marked 
with the following message: 
"THIS MIRROR IS NOT DESIGNED FOR USE 
WHILE THE VEHICLE IS IN MOTION." 

The NPRM identified three issues about these 
informational requirements: ( 1 ) The need for such 
a message; (2) the message's content; and (3) the 
message's location. As to location, the agency 
proposed that the message be placed directly on 
the minor, but requested comments about other 
possible locations. 

Regarding the need for an informational mes- f 
sage on convex cross view mirrors, only NSTA V 
and Thomas Built Buses believed that a message 



PART 571: Slll-PRE-^0 



was unnecessary. NSTA stated that the message 
could impair the mirror's effectiveness and dis- 
tract the driver. NSTA and Thomas Built said that 
the message was unnecessary because they 
believed that driver training would be more effec- 
tive than a label whose benefits were question- 
able. 

All other commenters supported having an 
informational label either expressly (Mirror Lite, 
R&R Research, Washington State, and Sloan 
Company) or implicitly (Transport Canada, Anne 
Arundel County Schools, New York State. Ten- 
nessee DOE, Arizona DOT, Lo-Mar, and Blue 
Bird) by not objecting to the label, while com- 
menting on the location, size, or wording of the 
warning. R&R Research stated that an informa- 
tional label was necessary because in practice 
drivers use cross view mirror systems to gain 
information on traffic conditions around the bus. 

After considering the comments, NHTSA has 
determined that a message explaining the proper 
use of convex cross view mirrors is necessary 
since some drivers use these mirrors for driving 
purposes. The agency is aware that properly 
trained drivers will have been taught that these 
mirrors are for pedestrian detection purposes only. 
Accordingly, NHTSA believes that the label will 
serve more as a reminder message rather than as 
an "instructional" message for those drivers 
trained in the proper operation of school buses 
and use of mirror systems. The agency believes 
that the message will also benefit untrained driv- 
ers, by informing them about the mirror system's 
proper use. 

As to the content of the message, R&R 
Research commented that the label should 
communicate two things: the correct action 
required of drivers, and the potential con- 
sequences of inappropriate behavior. NHTSA 
agrees with R&R's comment that a more positive, 
informative message would provide greater poten- 
tial safety benefits than the proposed one. Specifi- 
cally, the message adopted in the final rule 
explains what action should be taken (i.e., use the 
mirror to detect pedestrians), what action should 
not be taken (i.e., do not use the mirror to view 
traffic), and why the mirror should not be used 
inappropriately (i.e., the images do not accurately 
show another vehicle's location). Accordingly, the 
message required by the final rule has been 
changed to read as follows: 



"USE CROSS VIEW MIRRORS TO VIEW 
PEDESTRIANS WHILE BUS IS STOPPED. DO 
NOT USE THESE MIRRORS TO VIEW TRAF- 
FIC WHILE BUS IS MOVING. IMAGES IN 
SUCH MIRRORS DO NOT ACCURATELY 
SHOW ANOTHER VEHICLE'S LOCATION." 

Many commenters addressed the proper loca- 
tion for an informational message about cross 
view mirrors. Only Anne Arundel County favored 
placing the message on the mirror itself, claiming 
that placing this message elsewhere inside or out- 
side the bus would create problems since many 
buses already are required to contain several mes- 
sages. 

All other commenters, including R&R 
Research, New York State, Lo-Mar, Arizona 
DOT, Tennessee DOE, Transport Canada, 
Washington State, and Mirror Lite, recommended 
that the message be placed inside the school bus 
near the driver instead of on the cross view mir- 
ror itself. Commenters stated that a message 
placed directly on the mirror would be difficult to 
read and would obstruct some images, thus 
adversely affecting mirror performance. Tennessee 
DOE stated that the message should be placed on 
or near the instrument panel. New York State 
favored including the message on a sticker 
attached to the bus in the line of sight of the 
driver when observing the mirror. R&R Research 
favored placing the message inside the bus either 
on the instrument panel or near the interior rear 
view mirror. 

After considering the above comments, NHTAS 
has decided that the message should be located 
inside the school bus near the bus driver instead 
of on the convex cross view mirror. The agency 
agrees with the comments that a message placed 
directly on the mirror would be difficult to see 
and would reduce mirror performance by obscur- 
ing some mirror images. As noted above, the 
agency's primary goal is for drivers to understand 
that these mirrors should not be used while the 
vehicle is in motion because information obtained 
in such situations is not accurate enough to make 
appropriate driving decisions. 

The agency agrees with Anne Arundel County 
that the driver's area already contains a number 
of informational labels explaining proper school 
bus operations. Since the agency is unaware of 
any single "best" location for the mirror-use 
label, the final rule provides flexibility to bus 
manufacturers in placing the label at an appro- 



PART57I; Slll-PRE^l 



priate location which is prominent and visible 
within the driver's area of the bus. The standard 
requires the label to be printed in type face and 
color that are clear and conspicuous. NHTSA 
notes that these locations, size, and color require- 
ments are patterned after the warning label 
requirements for utility vehicles in 49 CFR 
575.105. 

f. Peiformance requirements for image clarity. 
The NPRM proposed performance requirements 
to ensure that the images in cross view mirrors 
were of sufficient minimum quality to provide the 
school bus driver with reliable infomiation about 
the presence of children in front of and along 
both sides of the bus. In selecting these proposed 
requirements, the agency relied on the VRTC 
report's finding that only a limited level of image 
quality is necessary to ensure that a school bus 
driver is aware of a student in a dangerous zone, 
so as not to move the bus until the student has 
moved to a safe location. 

The NPRM proposed two requirements to 
ensure adequate image quality. First, the separa- 
tion between the edge of each cylinder's image 
and the edge of the effective mirror surface would 
have to be not less than 3.0 minutes of arc. This 
requirement stems from the agency's finding that 
the most difficult images to recognize are elon- 
gated ones near the mirror's curved reflective 
edge. Second, with respect to the image of the 
cylinder perpendicular to and twelve feet away 
from the rear right axle, the angular size of the 
longest dimension of that image would have to be 
not less than nine minutes of arc and the angular 
size of its shortest dimension would have to be 
not less than three minutes of arc. This require- 
ment stems from the agency's finding that 
unreasonable elongation would make it difficult 
for the driver to identify a child's image in the 
mirror. 

Several commenters addressed the issue of 
image quality. Mirror Lite believed that a test 
procedure was necessary to reduce distortion due 
to a flawed mirror surface and to increase image 
quality. NSTA stated that only a reasonable level 
of image quality is necessary, since a driver needs 
only to recognize that an object in the mirror is 
a child and does not need to know specific details 
about the image. Thomas Built commented that 
the specification for the minimum distance 
between the image and the mirror's effective edge 
could be eliminated, believing that the elongation 



requirements of S9.4(b) (1) and (2) should make 
the image "acceptable." 

Commenters also provided general comments # 
about the image quality requirements. Transport ^ 
Canada stated that when a cylinder is visible in 
two mirrors, both images should have to meet the 
requirements for minimum size and distance from 
the mirror's edge, believing that this would ensure 
that a small child would not be overlooked. While 
Blue Bird agreed that the location of the image 
relative to the outer edge of the mirror surface 
should be limited, it believed that the proposed 
requirement of three minutes of arc would be dif- 
ficult to measure given its dependence on the fol- 
lowing variables: (1) The radius of effective mir- 
ror surface, (2) mirror adjustment by the driver, 
and (3) distance from the driver's eye location to 
the image in the mirror for different mirror com- 
binations and bus types on which mirrors are 
mounted. Blue Bird was concerned that this pro- 
posal would result in ambiguities given potential 
problems in accurately measuring the allowed 
mirror distance between the image and edge of 
the mirror. Blue Bird recommended establishing a 
limit on the distance between images and the mir- 
ror edge which it characterized as being more ^ 
easily measurable during compliance testing. \ 

Several commenters provided specific sugges- 
tions about changing the requirements for image 
quality. Thomas Built recommended that each 
cylinder's top surface have a letter which would 
be used to evaluate image clarity. Thomas Built 
believed that the proposed three minutes of arc 
was "minute and undeterminate," stating that on 
a mirror with a 28 inch radius of curvature, three 
minutes of arc is only .024 inches. Accordingly, 
Thomas Built suggested the requirement be elimi- 
nated unless a fixed dimension such as '/4 inch is 
specified. Similarly, Blue Bird suggested 
establishing a fixed distance of '/i6 inch along the 
effective mirror surface's edge to be blocked out 
during compliance testing. 

After reviewing the comments, NHTSA 
repeated several mirror evaluations and created 
charts representing a distance of three and nine 
minutes of arc for use in the proposed test proce- 
dure. (See Figure 4.) Based on that evaluation's 
results, the agency believes that three minutes of 
arc can be accurately measured and that this / 
dimension provides adequate separation between \^ 
the test cylinders and the effective edge of the 



PART 571; Slll-PRE-42 



mirror. Accordingly, the final rule adopts the pro- 
posed three minutes of arc requirement. 
^ As for Thomas Built's suggestion to letter the 

^^ tops of the cylinders, NHTSA notes that the 
VRTC report found that such precision is not nec- 
essary for the driver to recognize that a pedestrian 
is in danger. In addition, such a high level of 
precision might be impracticable for certain mir- 
rors that nonetheless provide an adequate field-of- 
view. Similarly, the agency believes that adopting 
Transport Canada's recommendation for multiple 
images of the same cylinder to comply with the 
image clarity requirements would be unnecessary 
for safety and would be redundant. Moreover, 
such a requirement appears to be impracticable 
based on the agency's evaluation of various mir- 
ror systems. 

As for the suggestions by Thomas Built and 
Blue Bird to establish a minimum fixed dimen- 
sion of either Vie or V4 inch between the test cyl- 
inder image and the mirror's effective edge, 
NHTSA believes such an approach would be nei- 
ther practicable nor appropriate. NHTSA notes 
that the "effective edge" of a convex mirror var- 
ies depending on the adjustment of the mirror and 
the driver's eye location. Accordingly, it is not 
^ feasible to specify a measurement from a variable 
location since the effective edge of a convex 
cross view mirror is often toward the center of 
the mirror, instead of at the actual edge of the 
mirror. 

g. Image elongation. As noted above, the 
NPRM proposed language controlling the mini- 
mum angular size of the image of the test cyl- 
inder located twelve feet perpendicular to the side 
of the bus at the right rear axle line. The purpose 
of this proposal was to ensure that the image 
would not appear unreasonably elongated, a 
phenomenon that might prevent drivers from 
being able to identify a child's image in the mir- 
ror. As noted in the VRTC report and in the 
agency's in-house evaluation, drivers have the 
most difficulty seeing images of objects along the 
axis perpendicular to the right rear wheel because 
some current designs of convex cross view mir- 
rors unreasonably elongate the image. 

Several commenters expressed their views 
about the elongation requirement. R&R Research 
stated that the proposed minimum image sizes of 
^ three minutes and nine minutes of arc would be 
w adequate as a minimum standard for most situa- 
tions. Nevertheless, it believed that occasionally a 



driver with poor vision in low contrast situations 
would not be able to detect objects in a mirror 
designed to comply with the proposed minimum 
image size requirements. 

Blue Bird objected to the proposed elongation 
requirements, claiming not to understand the use 
of cylinder N to measure distortion. Blue Bird 
believed that the agency did not justify the speci- 
fied angular dimensions for a distorted image 
viewed in any particular mirror, arguing that the 
proposed angular sizes may be too restrictive and 
may not correspond to real-world situations. In 
support of its argument. Blue Bird cited the 
VRTC report which stated that "It is better to 
have a 'distorted' object in the mirror than no 
object at all." Based on the above. Blue Bird 
requested that the agency conduct additional 
research to determine practical real-world limits 
for allowable image distortion. 

Commenters also offered specific recommenda- 
tions about the performance requirements for 
elongation. R&R Research suggested that the final 
rule contain either a table of target dimensions 
that subtend the three and nine minute visual 
angles when viewed at a specified distance or 
contain the mathematical formulae to calculate 
them. Lo-Mar requested that "angular size" be 
better defined, claiming that the angular size of 
the cylinder's image in the mirror is confusing. 
Nevertheless, Lo-Mar offered no specific sugges- 
tions. 

Transport Canada suggested that the image size 
requirements be extended to all cylinders in all 
mirrors, stating that cylinder N will not nec- 
essarily appear in the mirror at the mirror's 
smallest radius of curvamre. Transport Canada 
also suggested that the minimum angular size for 
cylinders A through F be five minutes of arc, and 
the minimum angular size for cylinders G through 
K be ten minutes of arc. 

After reviewing the comments and conducting 
additional mirror evaluations, NHTSA has 
decided to adopt the proposed requirements for 
minimum angular dimensions of test cylinder N 
in this final rule. The agency notes that the test 
cylinder identified as N in the NPRM is identified 
as cylinder P in this final rule. The agency 
believes that the elongation requirements are nec- 
essary to protect against poor image quality for 
objects toward the rear of the bus. 

In response to the comments from Transport 
Canada, Lo-Mar, and Blue Bird, the agency notes 



PART 571; Slll-PRE-43 



that test cylinder P will most often be located fur- 
ther toward the edge of the effective mirror sur- 
face than the other test cylinders. Therefore, cyl- 
inder P's image will typically be a worst-case 
image that is subjected to more spherical aberra- 
tion than other images that are further from the 
effective edge of the mirror. Because of this, the 
image of cylinder P will typically be the least 
clear. This fact, combined with test cylinder P 
being located the farthest away from the mirror 
and driver, indicates that controlling the image 
clarity of test cylinder P should effectively control 
the image clarity of all test cylinders. 

NHTSA believes that the minimum angular 
sizes (three minutes and nine minutes) adopted 
here in the elongation requirements are consistent 
with the dimensions adopted in the image clarity 
requirements for the distance from test cylinders 
to the effective edge of the mirror (three minutes). 
Both sets of dimensions were based on NHTSA 
mirror evaluations and the capabilities of these 
existing mirrors to meet those dimensional limits. 
While real-world evidence to define conclusively 
the optimum image sizes is not available, and 
may be impossible to obtain because of the many 
factors influencing the clarity of an image in a 
cross view mirror, the agency believes the 
adopted image clarity and elongation requirements 
are reasonable and practicable. Aside from the 
objections by Blue Bird and Lo-Mar, no other 
comments were received on this subject. The 
agency assumes that the other commenters tacitly 
approved the image clarity and elongation 
requirements since the NPRM expressly asked 
about the reasonableness and practicability of 
these requirements, a subject about which the 
commenters are generally knowledgeable. 

After reviewing R&R Research's comment 
about including a comparison chart and the 
mathematical formula, the agency has decided to 
modify the final rule to incorporate a size chart 
for three minutes and nine minutes of arc and the 
formulae for calculating them. 

E. Testing procedures 

1. General 

Based on the VRTC report and other agency 
findings, the agency proposed in section S13 cer- 
tain test procedures under which the proposed 
perfomiance requirements would be evaluated. As 
explained below, the NPRM proposed detailed 



specifications about the characteristics of test cyl- 
inders and their placement at critical locations in 
front of and along both sides of the school bus. ^ 
The NPRM also proposed a testing reference ^ 
point and testing procedures, including the 
photographing of test cylinders. 

2. Testing Reference Point 25th Percentile Female 

The NPRM proposed that compliance testing 
be measured relative to the center point of the eye 
location of a 25th percentile adult female rep- 
resented by a two dimensional manikin. The 
agency selected this sized driver because such a 
driver tends to have a poorer direct field-of-view 
of the area near the bus than a taller (e.g., 95th 
male percentile) driver. 

The proposed regulatory text in SI 3.2 con- 
tained specific information on determining the eye 
location of a 25th percentile adult female seated 
in the driver's seat. These provisions concerned 
the seat's position and adjustment procedures. 

Several commenters addressed the testing 
requirements related to the driver position. R&R 
Research believed that the standard need not refer 
to the 25th percentile female since precise dimen- 
sions from the seat are provided. Blue Bird dis- ^ 
agreed with the use of a 25th percentile female fl 
for identifying the eye location, stating that for ^ 
passenger cars. Standard No. HI uses a driver's 
eye location corresponding to a 95th percentile 
male. Notwithstanding its criticisms. Blue Bird 
acknowledged that the proposed eye location 
procedures would allow precise determination of 
the driver's eye location in any bus. Transport 
Canada believed that multiple eye locations 
should be used in the test procedure, including a 
5th percentile female and a 95th percentile male. 
It stated that the 95th percentile male provides the 
worst-case viewing in indirect field-of-view situa- 
tions since that type of driver sits farthest from 
the mirrors. 

After reviewing the comments, the agency 
continues to believe that the eye location of the 
25th percentile adult female is appropriate for 
representing a "worst case" for visibility. There- 
fore, the proposed requirements are adopted in 
this final rule. The agency notes that because the 
adopted requirements consider the bus's entire 
field-of-view and not just the indirect view cre- 
ated by miiTors, the 25th percentile female pro- A 
vides a more stringent testing perspective than a ^ 
95th percentile male. This consideration out- 



PART 571; S11I-PRE^4 



weighs the perceive benefits from having consist- 
ent reference points in Standard No. Ill for all 
I the different types of vehicles. 

The agency believes that Transport Canada's 
suggestion that eye locations be based on 95th 
percentile males and 5th percentile females would 
create excessive requirements. As discussed below 
in the section on "Camera Testing Points." the 
final rule allows for compliance within an area 
formed by the points of an arc located six inches 
to the left, forward, and right of the eye location 
of a 25th percentile adult female. Such a require- 
ment recognizes that drivers typically move their 
heads while viewing mirrors, and that the range 
of these movements would encompass eye loca- 
tions for various size drivers. 

As R&R Research stated, the final rule pro- 
vides dimensional information for locating the 
center point of the driver's eye location. Even 
though it may not be strictly necessary to do so, 
the agency believes that the rule should expressly 
state that the source of that dimensional informa- 
tion is the 25th percentile adult female. 

3. Mirror Adjustment During Testing 

The NPRM proposed that the mirrors be 
I adjusted in accordance with the manufacturer's 
recommendations (see S13.3). Several com- 
menters addressed the issue of mirror adjustment. 
R&R Researcher and Transport Canada stated that 
the agency should modify proposed SI 3.3 in the 
final rule to state that, once adjusted, the mirrors 
must remain fixed in one position throughout the 
measurement procedure. On the other hand. New 
York State commented that mirrors subject to 
Standard No. Ill should be remotely adjustable 
from the driver's seat to accommodate the eye 
locations of different size drivers. 

After reviewing the comments, NHTSA has 
decided to modify the language in SI 3.3 to pro- 
hibit moving or adjusting mirrors during compli- 
ance testing. The agency's intention in the NPRM 
was to require mirrors that would, once properly 
adjusted, afford the driver a clear view of children 
present around stopped school buses. Mirrors that 
must be repeatedly adjusted to view the entire 
area around the stopped bus would not effectuate 
that intention. In addition, mirrors that must be 
repeatedly adjusted are not likely to be adjusted 
I every time by the driver, which would mean there 
' potentially could still be situations where the 
driver could not detect child pedestrians around 



the stopped school bus. To ensure that the mirrors 
required by this final rule will not need any fur- 
ther adjustments after the initial one. this rule 
modifies the proposed language in SI 3.3 to make 
such a requirement explicit. 

This rule has not been modified in response to 
New York's comment about remotely adjustable 
mirrors. As explained above, the agency is seek- 
ing to require mirrors that will offer a clear view 
of the area around a stopped school bus without 
any further adjustments after the initial one. 
While remotely adjustable mirrors are now avail- 
able, they will not be considered as complying 
with this rule if they must use their adjustability 
characteristics to provide the required view during 
testing. 

4. Camera Testing Points 

The NPRM proposed that observations would 
be made and photographs taken of the test cyl- 
inders from a point representing the center of the 
driver's eye location for a 25th percentile adult 
female, as well as at locations six inches forward, 
left, and right of the center of the driver's eye 
location. These multiple positions were intended 
to account for head movements. Under the pro- 
posed test procedures, cylinders that were directly 
viewable would be evaluated first, and then cyl- 
inders that were not directly viewable would be 
evaluated. In both situations, the evaluator would 
look through a camera's film plane to determine 
whether the entire top surface of a test cylinder 
could be directly seen. A comparison chart placed 
above each mirror would serve as a reference 
point in evaluating the image size and amount of 
distortion of cylinders visible in a mirror. 

Many commenters addressed the requirements 
related to the camera locations. The Arizona DOT 
supported the proposed procedure. According to 
this commenter, it evaluated some existing mirror 
systems in accordance with the proposal and 
determined that the driver's eye location can be 
established and the camera location is correct. 

Other commenters either criticized the proposed 
camera-related testing procedures or offered 
suggestions to improve the requirements. Mirror 
Lite was concerned that the camera location 
requirements would be interpreted differently by 
various bus manufacturers, but did not explain the 
basis for its concern. Thomas Built requested that 
mirror systems should only have to meet the test 
requirements from any one of the allowable cam- 



PART 571; Slll-PRE-45 



era locations instead of all locations, claiming that 
the time and cost of conducting photographic tests 
at multiple locations would be unreasonable. In 
support of its request, Thomas Built stated that 
the proposed requirement would require it to 
evaluate 140 bus/driver seat combinations for any 
given mirror system since certification testing 
would have to be conducted on each type of bus 
with each type of driver seat offered. Since 
Thomas Built estimated that evaluating one seat 
in one bus with one mirror system required about 
80 man hours and $ 1 25 of photographic materials, 
it viewed the testing necessary to evaluate 140 
combinations as being overly burdensome. 

Blue Bird criticized using a camera to measure 
compliance, citing such concerns as the camera's 
monocular vision, the burden to customers of 
many photographs and their duplication for docu- 
mentation purposes, the camera's inability to 
define correctly the direct field of view, and its 
inability to consider adjustments made by humans 
in mirror visibility. 

Transport Canada requested that video cameras 
be allowed, claiming that their use would permit 
viewing of images superior to those seen by cam- 
eras. It also requested that the requirements pro- 
vide more detail on the focal length of the camera 
lens. 

After reviewing the comments, NHTSA agrees 
with Thomas Built that requiring testing at mul- 
tiple points would be overly burdensome and 
would not yield significantly more worthwhile 
information. Upon reexamination, the agency now 
believes that a more appropriate procedure would 
be to allow testing to be done at any point within 
a specified area around the 25th percentile adult 
female driver's eye location. Such a procedure 
more accurately accounts for real-world situations 
in which drivers typically move their heads while 
they view mirror systems. Based on the above, 
the agency is changing SI 3.4 in this final rule to 
allow compliance with the standard at any one of 
the four points specified in Figure 3 (point "A," 
"B," "C," or "D") or at any single point within 
a semicircular area established by a 15.24 centi- 
meter (6 inch) radius parallel to and forward of 
the center point. This viewing zone is illustrated 
in Figure 3. The agency anticipates that this 
modification will provide meaningful infomiation 
about the driver's view of critical areas around 
the bus, while reducing the photographic time and 



cost factors mentioned by Thomas Built by 75 
percent. The agency believes that if a vehicle 
manufacturer can establish compliance at one of 
the four testing points or any point in the semi- 
circle, then that mirror system on that school bus 
should provide an adequate field-of view given 
the small size of the semicircle. 

NHTSA believes that Blue Bird's concerns 
about a camera's monocular vision and its inabil- 
ity to define the direct field of view are philo- 
sophical in nature and relate to the inherent 
limitations of current technology. Given the avail- 
able means to demonstrate objectively compliance 
with this standard, NHTSA is unaware of any 
other means that would be as effective, as prac- 
ticable, and as easy to demonstrate as the use of 
a camera. 

As for Mirror Lite's claim that the camera 
location specifications were ambiguous, the 
agency disagrees. NHTSA believes that difficul- 
ties in interpretation are unlikely, because the 
camera location specifications are well defined 
and easily achieved in actual testing situations. 

As for Transport Canada's comment about 
video cameras, NHTSA has determined that this 
testing method is appropriate and should be per- 
mitted. Accordingly, the final rule at SI 3.4 has 
been modified. While video technology as a 
means for demonstrating compliance with this 
standard may currently be less practicable than 
still photography, the agency believes that techno- 
logical improvements may make video cameras a 
more viable option in the fuhare. The agency 
therefore has decided not to preclude their use. To 
accommodate this modification, the term "film 
plane" has been changed to "image plane." 

As for a lens focal length, the agency does not 
believe specifications about the focal length of 
lens are necessary. During the agency's mirror 
evaluations, lenses of various focal lengths were 
used to photograph the mirror images, including 
50 mm to 250 mm lenses. While the ability to 
analyze the results was acceptable with all lenses, 
the agency noted that less enlargement was nec- 
essary when using a lens with a longer focal 
length. The agency believes it is reasonable to 
allow the entity conducting the test to select the 
type of camera and lens best suited to its pur- 
poses. 



PART 571; S111-PRE^6 



F. Miscellaneous Considerations 

1 . Certification 

" Thomas Built requested that the mirror manu- 

facturer be responsible for certifying the image's 
quality and the bus manufacturer be responsible 
for certifying the field-of-view. It stated that this 
division of responsibility would simplify the test- 
ing and development process between mirror and 
bus manufacturer. 

NHTSA notes that Thomas Built's suggested 
certification scheme would be inconsistent with 
the scheme set forth in Standard No. 111. That 
standard is a "vehicle"" standard under which the 
vehicle manufacturer, and not the mirror manufac- 
turer, is responsible for ensuring that a mirror 
complies with the standard. This ensures that 
vehicles equipped with noncomplying mirrors will 
be quickly remedied, without the need for a spe- 
cific determination of whether the noncompliance 
arose because of an innate problem with the mir- 
ror or because of its installation on these particu- 
lar vehicles. The agency does not believe there is 
any reason to change this scheme for school 
buses under Standard No. 111. Notwithstanding 
this conclusion, the agency notes that a vehicle 

i manufacturer can establish in its purchase speci- 
fications whatever level of requirements it 
chooses for its suppliers and take appropriate 
actions if the supplier"s products fail to conform 
to those specifications. 

2. Retrofitting 

Several commenters, including the National 
PTA and the National Education Association 
(NEA), advocated that NHTSA require existing 
school buses to be retrofitted to comply with the 
new requirements. The National PTA stated that 
the agency's decision not to retrofit existing 
school buses was "based more on a lack of regu- 
latory courage than legal restrictions." 

The agency's statutory authority under the 
National Traffic and Motor Vehicle Safety Act 
(the Safety Act; 15 U.S.C. 1381 et seq.) is to 
issue safety standards applicable to new motor 
vehicles and new items of motor vehicle equip- 
ment before their first consumer purchase. The 
Safety Act expressly provides that vehicles and 
items of equipment are not required to continue 
to comply with all applicable safety standards 
' after their first purchase for purposes other than 
resale. See section 108(b)(1) of the Safety Act (15 



U.S.C. 1397(b)(1)). Thus, NHTSA's safety stand- 
ards regulate the manufacture and sale of new 
vehicles and items of motor vehicle equipment. 
Regardless of the agency's "regulatory courage," 
amendments to the safety standards do not and 
cannot require vehicles in service to comply with 
the requirements adopted in final rules. 

However, the individual States do have the 
authority to regulate vehicles in service. Notwith- 
standing the lack of Federal authority to order 
school buses already in service to meet these 
amended requirements, the agency anticipates that 
many in-use school buses already comply with or 
will be retrofitted by State and local authorities to 
comply with these amended requirements. 

3. Applying Requirements to Buses Other Than 
School Buses 

New York State recommended the agency 
apply the new field-of-view requirements to all 
transit-type vehicles that transport the public. 

NHTSA notes that New York's recommenda- 
tion to apply the field-of-view requirements to 
non-school buses is beyond the scope of this rule- 
making action, since the NPRM only proposed 
new requirements for school buses. The agency 
notes that the benefits of applying these require- 
ments to transit buses appear questionable since 
most school bus-related incidents involve children 
under the age of seven. Notwithstanding the 
above discussion, the agency does not prohibit 
using "school bus'" mirror systems on other types 
of buses. 

4. Heated Mirrors 

New York State and Moto Mirror requested 
that the agency require school buses to be 
equipped with heated mirrors, at least for those 
areas that experience cold weather. 

NHTSA recognizes that some northern portions 
of the country experience weather conditions 
where mirror systems can become covered with 
ice and snow. While these conditions affect the 
potential effectiveness of the mirror systems, 
NHTSA believes that the responsibility for 
maintaining the mirror systems, and any part of 
the vehicle which affects the performance of the 
mirror systems, is best left with the State and 
local school districts. The agency further notes 
that since school buses are manufactured for use 
in all parts of the country, they must comply with 
all applicable standards. Therefore, it would be 



PART 571; Slll-PRE-47 



unreasonable to promulgate a national standard 
that would have little or no benefit for a signifi- 
cant part of the country. 

5. Maximum Permissible Number of Mirrors 

Several commenters addressed the number of 
mirrors with which a school bus should be 
equipped. R & R Research believed that the new 
standard should address the number of mirrors 
allowed on a school bus and the size of the mir- 
rors. While the number of mirrors affect the time 
a driver needs to search visually the area around 
the bus, mirror size affects the blind spots created 
by the mirrors themselves. Transport Canada 
believed that the number of rear-view mirrors 
should be limited to one per side to avoid pos- 
sible confusion produced by multiple images and 
reduce the total time drivers must divert their 
attention from the road ahead. 

While NHTSA is aware of the situation men- 
tioned by R & R Research and Transport Canada, 
no provision limiting the number of mirrors on 
school buses has been included in this final rule 
because the agency does not believe that there 
would be a safety benefit from such a limitation. 
The agency further notes that a major purpose for 
this rulemaking's field-of-view approach is to 
allow school bus users and manufacturers to 
determine the best mirror system for their particu- 
lar operating environment. 

6. Blind Spots 

The NPRM requested comments about whether 
the mirrors would create dangerous blind spots in 
the driver's direct field-of-view, given the size 
and location of some convex cross view mirrors. 

Several commenters believed that the agency 
should address the potential problems of blind 
spots created by miiTors. R & R Research 
believed that any new standard should address the 
mirror size, since this affects the blind spots cre- 
ated by the mirrors themselves. Transport Canada 
suggested that mirrors be located in areas that do 
not obstruct the driver's direct view of traffic and 
pedestrians. Thomas Built and a bus driver com- 
mented that while convex cross view miiTors do 
not create significant blind spots, side mounted 
driving mirrors may decrease visibility. 

Other commenters believed that blind spots 
were not a significant safety problem. Arizona 
DOT stated that the increased field-of-view pro- 
vided by mirrors offsets the corresponding blind 



spots. Blue Bird stated that blind spots created by 
a cross view mirror on one side of the bus can 
be viewed in the cross view mirror system on the ^M 
other side of the bus. ^* 

NHTSA agrees with Arizona DOT that blind 
spots in the direct field-of-view created by mir- 
rors themselves are offset by the larger indirect 
field-of-view provided by the mirror system. 
Although NHTSA does not believe it is appro- 
priate to establish requirements for mirror loca- 
tions, the agency does believe that mirror and 
school bus manufacturers should strive to develop 
mirror locations which limit the amount of 
obstruction to the driver's direct field of view. 

7. Glare from Mirrors 

The NPRM asked whether glare from some 
cross view mirror designs, caused by turn signals 
and other school bus lights, would reflect light 
from flashing turn signals into the driver's eye. 

Of those who commented on this issue 
(Thomas Built. Blue Bird. Arizona, Mirror Lite, 
Tennessee), no commenter believed that glare 
caused a significant safety problem. Based on the 
comments, the agency does not believe that 
reflected light or glare from convex mirrors pre- ^ 
sents an unreasonable safety risk to school bus ^ 
drivers. 

8. Non-Mirror Systems 

The NPRM discussed the docket comments 
received about mechanical and electronic devices 
which could be used either to keep students away 
from critical areas around the school bus or to 
alert school bus drivers to the presence of some- 
one in a critical area around the bus. The agency 
explained that mirrors offer the most effective 
means of providing the school bus driver with a 
complete view in front of and along both sides of 
the bus. The agency believed that requiring these 
additional non-mirror devices "would substan- 
tially increase compliance costs without signifi- 
cantly increasing safety benefits." 

The Arizona DOT agreed that instead of requir- 
ing such devices, it would be more cost effective 
to evaluate their effectiveness through pilot pro- 
grams. SCAN, the manufacturer of an electronic 
detection system, requested that the agency mod- 
ify the field-of-view requirements to allow 
compliance through mirrors or sensing/detection M 
devices. SCAN believed that the NPRM was " 
unduly negative toward its type of product and 



PART 571; S111-PRE^8 



requested that critical comments from Blue Bird 
and Thomas Built about non-mirror systems be 
stricken from the docket. 

The agency continues to believe that, in terms 
of performance, reliability, and cost, mirrors offer 
the best means for school bus drivers to become 
aware of pedestrians in front of and along both 
sides of the bus. Accordingly, the agency does 
not agree with the SCAN's belief that sensing/ 
detection devices should be allowed as a means 
of meeting the standard's field-of-view require- 
ments. Notwithstanding this decision, sensing/ 
detection devices may be used as supplementary 
devices on school buses. 

G. Costs 

In previous notices, NHTSA considered the 
rulemaking's expected cost. The ANPRM esti- 
mated that the unit cost for a System B convex 
cross view mirror with a bracket plus installation 
would range from $52 to $107. The NPRM 
explained that the costs of an additional convex 
cross view mirror would range from $58 for a 
four 8" (17" ROC) convex mirror system to $121 
for an 8"xl2" quadrispheric "Bus Boy" mirror 
system. The proposal noted that, since school bus 
manufacturers and users were free to choose what 
convex cross view mirror system they would use 
to comply with the performance requirements, 
those parties' choices would greatly affect the 
ultimate costs. However, the agency anticipated 
that the cost of complying with the proposed 
changes would be minimal because of the current 
State mirror specifications. For example. States 
that currently specify four 8" (17" ROC) convex 
mirrors on cross view tripods, at a cost of $58.00, 
could switch to a pair of elliptical mirrors which 
cost nearly the same — $58.10. 

The NPRM requested comments about this 
proposal's cost to school bus users and informa- 
tion about current State requirements for school 
bus mirrors. 

Several commenters, including States and 
school bus manufacmrers, generally agreed with 
the NPRM's cost estimates. The Arizona DOT 
and Tennessee DOE commented that the NPRM's 
cost estimates were accurate. Mirror Lite com- 
mented that the parts cost (i.e., mirrors and 
mounting arms) of four currently used standard 8" 
mirrors on a conventional bus is $44; while, the 
cost of two Bus Boy mirrors and brackets would 
be $5 1 , a $7 difference. While Mirror Lite did not 



provide a cost for installation, the agency believes 
that the installation cost for two Bus Boy mirrors 
would be approximately the same as four 8" con- 
vex mirrors, if two such mirrors are mounted on 
the same bracket. 

A few commenters believed the rulemaking 
would result in significant additional costs. Moto 
Mirror, a mirror manufacturer, stated that the 
aftermarket cost of a dual set of motorized and 
heated mirrors would be $362.05. The agency 
notes that these mirrors include motorized and 
heated features that the standard does not require. 
Blue Bird commented that available mirror sys- 
tems that will meet the proposals have an addi- 
tional cost of approximately $115.00 per bus 
above the cost of the standard mirror system it 
currently uses. R&R Research believed that the 
cost of installation and adjustment may exceed 
the cost of the hardware for some mirror systems, 
but provided no details to support the statement. 

After reviewing the available information, 
NHTSA believes that the NPRM's initial cost 
estimates are generally reasonable. With respect 
to System A costs, the agency notes that all buses 
are typically equipped with supplemental convex 
driving mirrors as part of their System A mirrors. 
Thus, no real change in these mirrors would be 
necessary for school bus users to meet System A 
requirements. As for R&R Research's concern 
about installation, the agency has discussed mirror 
installation with bus manufacturers and State and 
local school district officials at various school 
transportation trade shows and has not found any 
supporting information for R&R's claim. 

As to Blue Bird's comment on the $115 dif- 
ference in the cost for a compliant mirror system, 
they were referring to a quadrispheric mirror sys- 
tem. They also inadvertently included the cost of 
the right and left side flat, rearview mirrors as 
part of the cost increase; this was not appropriate. 
Blue Bird resubmitted a cost increase of $30 per 
bus, to the consumer, when equipped with a 
quadrispheric mirror system rather than the stand- 
ard four 8" convex cross view mirror system. 
They further stated that as such mirror systems 
gain popularity among the users, that cost will 
drop. 

With regard to Thomas Built's estimate of 80 
man hours needed to complete a compliance test 
of a single bus-seat-mirror combination, it has 
been the agency's experience, through VRTC, 
that about ten man hours are necessary to do this 



PART 571; Slll-PRE-49 



type of test. Included in the agency's time esti- 
mate are such tasks as locating the cylinders 
around the bus, adjusting the mirrors, mounting a 
camera tripod in the driver's seat area, taking 
slides, processing film, and analyzing slides. The 
agency's estimate does not include one-time tasks 
such as setting up a grid of one foot by one foot 
squares and the constructing the test cylinders. 
Although many bus-seat-mirror configurations 
will need to be tested, once a particular configura- 
tion has been certified to meet the standard, that 
configuration will not need to be retested in sub- 
sequent years. Therefore, such one-time test costs 
would be distributed over the years that such a 
configuration is in use. Also, the agency believes 
that a limited number of design changes in bus 
exteriors and/or drivers' seats occur from year to 
year and any differences in the location of the 
25th percentile adult female's eye location that do 
occur would be small and should not greatly 
affect the driver's direct or indirect field of view. 
These eye location differences among seats 
would, however, establish a compliance 
"envelope" spanning the eye locations that allow 
compliance with the standard. Thus, further 
reductions in time and cost would occur by not 
having to test any new configurations that would 
have minute eye location differences between pre- 
viously tested configurations. Finally, the agency 
expects that further time savings will occur as 
more and more tests are performed. 

H. Leadtime Requirements 

The NPRM explained that many mirror systems 
are now available which would comply with the 
proposed field-of-view requirements, and thus 
would not create leadtime constraints from that 
perspective. Nevertheless, the agency believed 
that school bus manufacturers and users should be 
afforded time to investigate and select how they 
wish to comply with the new field-of-view 
requirements. Accordingly, the agency proposed 
an effective date of one year after publication of 
the final rule. 

Several commenters addressed the leadtime 
necessary for this rulemaking. The NEA favored 
having the final rule become effective as soon as 
possible. The Arizona DOT stated that there cur- 
rently are mirrors that could be used to comply 
with the one year leadtime requirements. NSTA 
requested a leadtime of 18 months after publica- 
tion of the final rule for the effective date, claim- 



ing that additional time was necessary to allow 
school districts to budget for the additional costs 
associated with the rulemaking. ^| 

After reviewing the comments, the agency ^* 
continues to believe that a one-year leadtime after 
the final rule's publication provides adequate time 
for school bus manufacturers and users to deter- 
mine how to comply with the new field-of-view 
requirements. The agency notes that most school 
bus manufacturers are already familiar with all of 
the brands of mirrors. The extra six months 
requested by NSTA is not warranted on the basis 
of other comments. 

This final rule does not have any retroactive 
effect. Under section 103(d) of the National Traf- 
fic and Motor Vehicle Safety Act (15 U.S.C. 
1392(d)), whenever a Federal motor vehicle safety 
standard is in effect, a State may not adopt or 
maintain a safety standard applicable to the same 
aspect of performance which is not identical to 
the Federal standard. Section 105 of the Act (15 
U.S.C. 1394) sets forth a procedure for judicial 
review of final rules establishing, amending or 
revoking Federal motor vehicle safety standards. 
That section does not require submission of a 
petition for reconsideration or other administrative ^ 
proceedings before parties may file suit in court. ^ 

Rulemaking Analyses and Notices 

Executive Order 12291 (Federal Regulation) and 
DOT Regulatoi-y Policies and Procedures 

NHTSA has considered the costs and other 
impacts of this rulemaking, and a Final Regu- 
latory Evaluation (FRE) has been prepared and 
placed in the docket. Based on this evaluation, the 
agency has determined that the rulemaking is not 
■'major" within the meaning of Executive Order 
12291. However, it is "significant" within the 
meaning of the Department of Transportation's 
regulatory policies and procedures. 

As explained in the FRE, the additional cost of 
installing a pair of compliant convex cross view 
mirrors on a new school bus could range from no 
cost to as much as $30 per school bus, depending 
on the type of mirror system selected by the 
school district. About 38,000 new school buses 
are sold each year, and according to Blue Bird 
about 12 percent of all their buses are equipped 
with a compliant mirror system. Therefore, ^ 
assuming Blue Bird's sales breakdown is rep- ^ 
resentative of the overall bus manufacturing 



PART 571; Slll-PRE-50 



industry, about 33,440 buses (38,000 x 88 per- 
cent) will have to be equipped with a compliant 
) system. Therefore, the aggregate annual cost to 
consumers would range from no cost to about 
$1,003,200. (33,400 x $30 per bus). 

NHTSA anticipates that the actual costs will 
likely be nearer the lower end of the estimated 
cost range for the following reasons. Buyers will 
probably select lower cost mirrors since they are 
quite sensitive to cost. At the same time, econo- 
mies of scale and competition will lower the costs 
of the more expensive mirrors. The agency further 
notes that since nearly all States now require 
school buses to have more mirrors than required 
by FMVSS No. Ill, the costs of complying with 
this rulemaking could even result in a cost sav- 
ings for those school buses being sold in jurisdic- 
tions where buses are currently equipped with 
more expensive mirrors than a mirror system that 
will now be allowed under the amendments. 

As mentioned in this notice's "background" 
section, an average of 26 students are fatally 
injured and another 283 are injured when struck 
by their own school bus. While the effectiveness 
of upgrading the requirements for school bus mir- 
i TOTS cannot be conclusively established, accounts 
' in the NAS report and docket comments indicate 
that some injuries and fatalities will be avoided. 

Regiilatoiy Flexibility Act 

NHTSA has considered the effects of this 
action under the Regulatory Flexibility Act. I 
hereby certify that it will not have a significant 
economic impact on a substantial number of small 
entities. School bus manufacturers are generally 
not small businesses within the meaning of the 
Regulatory Flexibility Act. Small governmental 
units and small organizations are generally 
affected by amendments to the Federal motor 
vehicle safety standards as purchasers of new 
school buses. However, as discussed above, such 
entities that purchase school buses should see lit- 
tle change with regard to the price of new buses 
that are equipped with compliant mirrors. In addi- 
tion, the agency notes that less than six mirror 
manufacturers provide nearly all of the school bus 
mirrors in use today. Although they are small 
companies, each has a full product line, including 
mirrors that can meet the amended standard. 
' Thus, the likely impact should only be a shift in 
sales of particular mirror types. Accordingly, the 



agency has determined that preparation of a regu- 
latory flexibility analysis is unnecessary. 

Executive Order 12612 (Federalism) 

This rulemaking has been analyzed in accord- 
ance with the principles and criteria contained in 
Executive Order 12612, and NHTSA has deter- 
mined that it does not have sufficient federalism 
implications to warrant preparation of a Federal- 
ism Assessment. 

In its analysis, the agency considered the 
amendment's likely effect on the States and pos- 
sible alternatives to the rulemaking. The agency 
has determined that virtually all States require 
school buses to be equipped with more mirrors 
than current Standard No. 1 1 1 requires. As this 
preamble explained earlier, the amendment pro- 
vides general performance-oriented requirements 
that the States may exceed. Although the amend- 
ments will supersede the current school bus mir- 
ror requirements of a large number of States, any 
required State regulatory changes will only 
involve a relatively minor administrative or legis- 
lative action that should not require extensive 
discussion or debate, since the change will 
improve the level of driver visibility. In addition, 
because the amendment eliminates current spe- 
cific requirements which serve to prohibit certain 
mirror designs, the rulemaking provides additional 
flexibility to the States. The agency further notes 
that the amended requirements are similar to the 
recommendation approved by 86 percent of the 
State representatives at the 11th National Con- 
ference on School Transportation. In addition. 
State commenters to the NPRM favored the field- 
of-view requirements. NHTSA accordingly does 
not expect any significant adverse effect on the 
States as a result of this rulemaking. 

National Environmental Policy Act 

NHTSA has also analyzed this rulemaking 
action for purposes of the National Environmental 
Policy Act. The agency has determined that 
implementation of this action will not have any 
significant impact on the quality of the human 
envirormient. Although there will likely be an 
increase in production of certain mirror types, this 
increase will not introduce any new or particu- 
larly harmful effects to the environment. 



PART 571: S111-PRE-5I 



Part 571— Federal Motor Vehicle Safety Stand- 
ards 

In consideration of the foregoing, 49 CFR part 
57 1 is amended, as follows: 

1 . The authority citation for part 57 1 of title 49 
continues to read as follows: 

Authority: 15 U.S.C. 1392, 1401, 1403, 
1407; delegation of authority at 49 CFR 1.50. 

§571.111 [Amended] 

2. In §571.111, S4 is amended by adding the 
following definition in alphabetical order. 

=f: * * * * 

Effective minor surface means the portions of 
a mirror that reflect images, excluding the mirror 
rim or mounting brackets. 

***** 

3. In §571.111, S9 through S9.2(b) is revised 
and a new S9.3 through S9.4(b)(2) is added, to 
read as follows: 

S9. Requirements for School Buses. When a 
school bus is tested in accordance with the proce- 
dures of SI 3, it shall meet the requirements of 
S9.1 through S9.4. 

59.1 Outside Rearview Mirrors. Each school 
bus shall have two outside rearview mirror sys- 
tems: System A and System B. 

59.2 System A shall be located with stable 
supports so that the portion of the system on the 
bus's left side, and the portion on its right side, 
each: 

(a) Includes at least one mirror of unit mag- 
nification with not less than 322.60 square centi- 
meters (50 square inches) of reflective surface; 
and 

(b) Includes one or more mirrors which 
together provide, at the driver's eye location, a 
view of: 

(1) For the mirror system on the right side 
of the bus, the entire top surface of cylinder N 
in Figure 2, and of that area of the ground 
which extends rearward from the mirror surface 
not less than 60.93 meters (200 feet). 

(2) For the mirror system on the left side of 
the bus, the entire top surface of cylinder M in 
Figure 2, and of that area of the ground which 
extends rearward from the mirror surface not 
less than 60.93 meters (200 feet). 

S9.3(a) For each of the cylinders A through P 
whose entire top surface is not directly visible 



from the driver's eye location, System B shall 
provide, at that location: 

(1) A view of the entire top surface of that 
cylinder. 

(2) A view of the ground that overlaps with 
the view of the ground provided by system A. 

(b) Each mirror installed in compliance with 
S9.3(a) shall meet the following requirements: 

(1) Each mirror shall have a projected area 
of at least 258.08 square centimeters (40 square 
inches), as measured on a plane at a right angle 
to the mirror's axis. 

(2) Each mirror shall be located such that the 
distance from the center point of the eye loca- 
tion of a 25th percentile adult female seated in 
the driver's seat to the center of the mirror 
shall be at least 95.25 centimeters (37.5 
inches). 

(3) Each mirror shall have no discontinuities 
in the slope of the surface of the mirror. 

(4) Each mirror system shall be installed 
with a stable support designed to dampen 
vibration. 

(c) Each school bus which has a mirror 
installed in compliance with S9.3(a) that has an 
average radius of curvature of less than 88.90 
centimeters (35 inches), as determined under SI 2, 
shall have a label visible to the seated driver. The 
label shall be printed in a type face and color that 
are clear and conspicuous. The label shall state 
the following: 

"USE CROSS VIEW MIRRORS TO VIEW 
PEDESTRIANS WHILE BUS IS STOPPED. DO 
NOT USE THESE MIRRORS TO VIEW TRAF- 
FIC WHILE BUS IS MOVING. IMAGES IN 
SUCH MIRRORS DO NOT ACCURATELY 
SHOW ANOTHER VEHICLE'S LOCATION." 

S9.4(a) Each image required by S9.3(a)(l) to 
be visible at the driver's eye location shall be 
separated from the edge of the effective mirror 
surface of the mirror providing that image by a 
distance of not less than 3 minutes of arc. 

(b) The image required by S9.3(a)(l) of cyl- 
inder P shall meet the following requirements: 

(1) The angular size of the shortest dimen- 
sion of that cylinder's image shall be not less 
than 3 minutes of arc; and 

(2) The angular size of the longest dimension 
of that cylinder's image shall be not less than 
9 minutes of arc. 



PART 571; Slll-PRE-52 



4. Section 571.111 is amended by adding a 
new S13 through SI 3.6, to read as follows: 

SI 3. School bus minor test procedures. The 
requirements of S9.1 through S9.4 shall be met 
when the vehicle is tested in accordance with the 
following conditions. 

513.1 The cylinders shall be a color which 
provides a high contrast with the surface on 
which the bus is parked. 

51 3.2 The cylinders are 0.3048 meters (1 
foot) high and 0.3048 meters (1 foot) in diameter, 
except for cylinder P which is 0.9114 meters (3 
feet) high and 0.3048 meters (1 foot) in diameter. 

51 3.3 Place cylinders at locations as specified 
in SI 3.3(a) through SI 3.3(g) and illustrated in 
Figure 2. Measure the distances shown in Figure 
2 from a cylinder to another object from the cen- 
ter of the cylinder as viewed from above. 

(a) Place cylinders G, H, and I so that they are 
tangent to a transverse vertical plane tangent to 
the forward-most surface of the bus's front 
bumper. Place cylinders D, E, F so that their cen- 
ters are located in a transverse vertical plane that 
is 1.8288 meters (6 feet) forward of a transverse 
vertical plane passing through the centers of cyl- 
inders G, H, and I. Place cylinders A, B, and C 
so that their centers are located in a transverse 
vertical plane that is 3.6576 meters (12 feet) for- 
ward of the transverse vertical plane passing 
through the centers of cylinders G, H, and I. 

(b) Place cylinders B, E, and H so that their 
centers are in a longitudinal vertical plane that 
passes through the bus's longitudinal centerline. 

(c) Place cylinders A, D, and G so that their 
centers are in a longitudinal vertical plane that is 
tangent to the most outboard edge of the left side 
of the bus's front bumper. 

(d) Place cylinders C, F. and I so that their cen- 
ters are in a longitudinal vertical plane that is tan- 



gent to the most outboard edge of the right side 
of the bus's front bumper. 

(e) Place cylinder J so that its center is in a 
longitudinal vertical plane 0.3048 meters (1 foot) 
to the left of the longitudinal vertical plane pass- 
ing through the centers of cylinders A, D, and G, 
and is in the transverse vertical plane that passes 
through the centerline of the bus's front axle. 

(f) Place cylinder K so that its center is in a 
longitudinal vertical plane 0.3048 meters (1 foot) 
to the right of the longitudinal vertical plane pass- 
ing through the centers of cylinders C, F, and I, 
and is in the transverse vertical plane that passes 
through the centerline of the bus's front axle. 

(g) Place cylinders L, M, N, O, and P so that 
their centers are in the transverse vertical plane 
that passes through the centerline of the bus's rear 
axle. Place cylinder L so that its center is in a 
longitudinal vertical plane that is 1.8288 meters (6 
feet) to the left of the longitudinal vertical plane 
tangent to the bus's most outboard left surface 
(excluding the mirror system). Place cylinder M 
so that its center is in a longitudinal vertical plane 
that is 0.3048 meters (1 foot) to the left of the 
longitudinal vertical plane tangent to the left side 
of the bus. Place cylinder N so that its center is 
in a longitudinal vertical plane that is 0.3048 
meters (1 foot) to the right of the longitudinal 
vertical plane tangent to the right side of the bus. 
Place cylinder O so that its center is in a longitu- 
dinal vertical plane that is 1.8288 meters (6 feet) 
to the right of the longitudinal vertical plane tan- 
gent to the right side of the bus. Place cylinder 
P so that its center is in a longitudinal vertical 
plane that is 3.6576 meters (12 feet) to the right 
of the longitudinal vertical plane tangent to the 
right side of the bus. 



PART 571: Slll-PRE-53 



3.6S76m(12ft) 
1.6288 m (6 ft) 



E F 

• • 
H I 



■ Test Cylinder 



J 

• 


o • • 




L M 

• • 





Centerline of 
Front Axle 



N O 



Cenierline of 
Rear Axle 



] 0.3048 md ft) I 



V 

3.6576 m (12 ft) 



1.6288 m (6 ft) 



1.6288 m (6 ft) 



Figure 2 
Location of Test Cylinders for Sciiool Bus Field-of-View Test 



PART 571; Slll-PRE-54 




15.24 cm (6 in) 



15.24 cm (6 in) 



Figure 3 
Camera Locations for Scliool Bus Field-of-View Test 



PART 571; Slll-PRE-55 



513.2 The driver's eye location is the eye 
location of a 25th percentile adult female, when 
seated in the driver's seat as follows: 

(a) The center point of the driver's eye location 
is the point located 63.58 centimeters (27 inches) 
vertically above the intersection of the seat cush- 
ion and the seat back at the longitudinal center- 
line of the seat. 

(b) Adjust the driver's seat to the midway point 
between the forward-most and rear-most posi- 
tions, and if separately adjustable in the vertical 
direction, adjust to the lowest position. If an 
adjustment position does not exist at the midway 
point, use the closest adjustment position to the 
rear of the midpoint. If a seat back is adjustable, 
adjust the seat back angle to the manufacturer's 
nominal design riding position in accordance with 
the manufacturer's recommendations. 

513.3 Adjustable minors are adjusted before 
the test in accordance with the manufacturer's 



recommendations. Such mirrors are not moved or 
readjusted at any time during the test. 

51 3.4 Place a 35 mm or larger format cam- 
era, or video camera, so that its image plane is 
located at the center point of the driver's eye 
location or at any single point within a semi- 
circular area established by a 15.24 centimeter (6 
inch) radius parallel to and forward of the center 
point (see figure 3). With the camera at any sin- 
gle location on or within that semicircle look 
through the camera and the windows of the bus 
and determine whether the entire top surface of 
each cylinder is directly visible. 

51 3.5 For each cylinder whose entire top sur- 
face is determined under paragraph 13.4 of this 
section not to be directly visible at the driver's 
eye location, 

(a) Place a comparison chart (see figure 4) 
above the mirror that provides the fullest view of 
the cylinder in situations where a cylinder is par- 
tially visible through more than one mirror. 



3 minutes 9 minutes 

of arc of arc 

Not Actual Size 



Figure 4. 
Comparison Chart for Indirect Field-of-View Measurements 



The width of the bars in Figure 4 indicating 
three minutes of arc and nine minutes of arc are 
derived from the following formula: 

For 3 minutes of arc: 
X=Dx0.000873, 



Where: 

X=the width of a line, in the unit of measure- 
ment D, representing 3 minutes of arc: 



PART 571; Slll-PRE-56 



D=distance from center point of driver's eye 
location to the center of the mirror's sur- 
face; and 

0.000873=tangent of 3 minutes of arc. 

For 9 minutes of arc: 

X=Dx0.002618, 

Where: 

X=the width of a line, in the unit of measure- 
ment D, representing 9 minutes of arc; 

D=distance from center point of driver's eye 
location to the center of the mirror's sur- 
face; and 

0.0026 18=tangent of 9 minutes of arc. 

(b) Photograph each cylinder through the 
mirror(s) that provides a view of the cylinder. 
Photograph each cylinder with the camera located 



so that the view through its film or image plane 
is located at any single location within the semi- 
circle established under 13.4, [POINT A,B,C, OR 
D] ensuring that the image of the mirror and 
comparison chart fill the camera's view finder to 
the extent possible. 

SI 3.6 Make all observations and take all 
photographs with the service/entry door in the 
closed position and the stop signal arm(s) in the 
fully retracted position. 

Issued on: November 24, 1992. 

Marion C. Blakey 
Administrator. 

57 F.R. 57000 
December 2, 1992 



PART 571; Slll-PRE-57 



MOTOR VEHICLE SAFETY STANDARD NO. 
Rearview Mirrors 



111 



51. Scope. This standard specifies requirements 
for the performance and location of rearview 
mirrors. 

52. Purpose. The purpose of this standard is to 
reduce the number of deaths and injuries that 
occur when the driver of a motor vehicle does not 
have a clear and reasonably unobstructed view to 
the real. 

53. Application. This standard applies to pas- 
senger cars, multipurpose passenger vehicles, 
trucks, buses, school buses and motorcycles. 

54. Definition. Convex mirror means a mirror 
having a curved reflective surface whose shape is 
the same as that of the exterior surface of a sec- 
tion of a sphere. 

\_Ejfective mirror surface means the portions of 
a mirror that reflect images, excluding the min-or 
rim or mounting brackets. (57 F.R. 57000 — Decem- 
ber 2, 1992. Effective: December 2, 1993)] 

Unit magnification mirror means a plane or flat 
mirror with a reflective surface through which the 
angular height and width of the image of an 
object is equal to the angular height and width of 
the object when viewed directly at the same dis- 
tance except for flaws that do not exceed normal 
manufacturing tolerances. For the purposes of this 
regulation a prismatic day-night adjustment rear- 
view mirror one of whose positions provides unit 
magnification is considered a unit magnification 
mirror. 

55. Requirements for passenger cars. 

S5.1. Inside rearview mirror. Each passenger 
car shall have an inside rearview mirror of unit 
magnification. 

S5.1.1. Field of view. Except as provided in 
S5.3, the mirror shall provide a field of view with 
an included horizontal angle measured from the 
projected eye point of at least 20 degrees, and 
sufficient vertical angle to provide a view of a 



level road surface extending to the horizon begin- 
ning at a point not greater than 200 feet to the rear 
of the vehicle when the vehicle is occupied by the 
driver and four passengers or the designed occu- 
pant capacity, if less, based on an average occu- 
pant weight of 150 pounds. The line of sight may 
be partially obscured by seated occupants or by 
head restraints. The location of the driver's eye 
reference points shall be those established in 
Motor Vehicle Safety Standard No. 104 
(§571.104) or a nominal location appropriate for 
any 95th percentile male driver. 

S5.1.2. Mounting. The mirror mounting shall 
provide a stable support for the mirror, and shall 
provide for mirror adjustment by tilting in both the 
horizontal and vertical directions. If the mirror is 
in the head impact area, the mounting shall 
deflect, collapse or break away without leaving 
shaip edges when the reflective surface of the mir- 
ror is subjected to a force of 90 pounds in any for- 
ward direction that is not more than 45° from the 
forward longitudinal direction. 

S5.2. Outside rearview mirror — driver's side. 

55.2.1. Field of view. Each passenger car shall 
have an outside mirror of unit magnification. The 
mirror shall provide the driver a view of a level 
road surface extending to the horizon from a line, 
perpendicular to a longitudinal plane tangent to 
the driver's side of the vehicle at the widest point, 
extending 8 feet out from the tangent plane 35 feet 
behind the driver's eyes, with the seat in the rear- 
most position. The line of sight may be partially 
obscured by the rear body or fender contours. The 
location of the driver's eye reference points shall 
be those established in Motor Vehicle Safety 
Standard No. 104 (§571.104) or a nominal loca- 
tion appropriate for any 95th percentile male 
driver. 

55.2.2. Mounting. The mirror mounting shall 
provide a stable support for the mirror, and neither 
the mirror nor the mounting shall protrude farther 



PART 571; S 111-1 



(Rev. 12/2/92) 



than the widest part of the vehicle body except to 
the extent necessary to produce a field of view 
meeting or exceeding the requirements of S5.2.1. 
The mirror shall not be obscured by the unwiped 
portion of the windshield, and shall be adjustable 
by tilting in both horizontal and vertical directions 
from the driver's seated position. The mirror and 
mounting shall be free of sharp points or edges 
that could contribute to pedestrian injury. 

55.3. Outside rearview mirror passenger's 
side. Each passenger car whose inside rearview 
mirror does not meet the field of view require- 
ments of S5.1.1 shall have an outside mirror of 
unit magnification or a convex mirror installed on 
the passenger's side. The mirror mounting shall 
provide a stable support and be free of sharp 
points or edges that could contribute to pedestrian 
injury. The mirror need not be capable of adjust- 
ment by tilting in both horizontal and vertical 
directions. 

55.4. Convex mirror requirements. Each motor 
vehicle using a convex mirror to meet the require- 
ments of S5.3 shall comply with the following 
requirements: 

55.4.1. When each convex mirror is tested in 
accordance with the procedures specified in S12 
of this standard, none of the radii of curvature 
readings shall deviate from the average radius of 
curvature by more than plus or minus 12.5 per- 
cent. 

55.4.2. Each convex mirror shall have perma- 
nently and indelibly marked at the lower edge of 
the mirror's reflective surface, in letters not less 
than V\6 inch or more than V4 inch high, the 
words "Objects in MiiTor Are Closer Than They 
Appear." (48 F.R. 38842— August 26, 1983. Effec- 
tive: August 26, 1983) 

55.4.3. The average radius of curvature of each 
such mirror, as determined by using the procedure 
in SI 2, shall be not less than 35 inches and not 
more than 65 inches. 



56. Requirements for multipurpose pas- 
senger vehicles, trucks, and buses, other than 
school buses, with GVWR of 10,000 pounds or 
less. 

S6.1. Each multipurpose passenger vehicle, truck 
and bus, other than a school bus, with a GVWR 
of 10,000 pounds or less shall have either — 

(a) Mirrors that conform to the requirements of 
S5; or 

(b) Outside minors of unit magnification, each 
with not less than 19.5 in- of reflective surface, 
installed with stable supports on both sides of the 
vehicle, located so as to provide the driver a view 
to the rear along both sides of the vehicle, and 
adjustable in both the horizontal and vertical 
directions to view the rearward scene. 

57. Requirements for multipurpose pas- 
senger vehicles and trucks with a GVWR of 
more than 10,000 and less than 25,000 pounds 
and buses, other than school buses, with a 
GVWR of more than 10,000 pounds. 

S7.1. Each multipurpose passenger vehicle and 
trucks with a GVWR of more than 10,000 pounds 
and less than 25,000 pounds and each bus, other 
than a school bus, with a GVWR of more than 
10,000 pounds shall have outside mirrors of unit 
magnification, each with not less than 50 in- of 
reflective surface, installed with stable supports on 
both sides of the vehicle. The mirrors shall be 
located so as to provide the driver a view to the 
rear along both sides of the vehicle and shall be 
adjustable both in the horizontal and vertical 
directions to view the rearward scene. 

58. Requirements for multipurpose pas- 
senger vehicles and trucks with a GVWR of 
25,000 pounds or more. 

S8.1. Each multipurpose passenger vehicle and 
truck with a GVWR of 25,000 pounds or more 
shall have outside mirrors of unit magnification, 
each with not less than 50 in- of reflective surface, 
installed with stable supports on both sides of the 
vehicle. The mirrors shall be located so as to pro- 
vide the driver a view to the rear along both sides 
of the vehicle and shall be adjustable both in the 



(Rev. 8/26/83) 



PART 571; S 111-2 



horizontal and vertical directions to view the rear- 
ward scene. 

[S9. Requirements for School Buses. When a 
school bus is tested in accordance with the proce- 
dures of SI 3, it shall meet the requirements of 
S9.1 through S9.4. 

59.1 Outside Rearview IVIirrors. Each school 
bus shall have two outside rearview mirror sys- 
tems: System A and System B. 

59.2 System A shall be located with stable sup- 
ports so that the portion of the system on the bus's 
left side, and the portion on its right side, each: 

(a) Includes at least one minor of unit mag- 
nification with not less than 322.60 square centi- 
meters (50 square inches) of reflective surface; 
and 

(b) Includes one or more mirrors which 
together provide, at the driver's eye location, a 
view of: 

(1) For the mirror system on the right side 
of the bus, the entire top surface of cylinder N 
in Figure 2, and of that area of the ground 
which extends rearward from the mirror surface 
not less than 60.93 meters (200 feet). 

(2) For the mirror system on the left side of 
the bus, the entire top surface of cylinder M in 
Figure 2, and of that area of the ground which 
extends rearward from the mirror surface not 
less than 60.93 meters (200 feet). 

59.3 (a) For each of the cylinders A through P 
whose entire top surface is not directly visible 
from the driver's eye location. System B shall pro- 
vide, at that location: 

( 1 ) A view of the entire top surface of that 
cylinder. 

(2) A view of the ground that overlaps with 
the view of the ground provided by system A. 
(b) Each mirror installed in compliance with 

S9.3(a) shall meet the following requirements: 

(1) Each mirror shall have a projected area 
of at least 258.08 square centimeters (40 square 
inches), as measured on a plane at a right angle 
to the mirror's axis. 

(2) Each mirror shall be located such that the 
distance from the center point of the eye loca- 
tion of a 25th percentile adult female seated in 
the driver's seat to the center of the mirror 
shall be at least 95.25 centimeters (37.5 
inches). 



(3) Each mirror shall have no discontinuities 
in the slope of the surface of the mirror. 

(4) Each mirror system shall be installed 
with a stable support designed to dampen 
vibration. 

(c) Each school bus which has a mirror 
installed in compliance with S9.3(a) that has an 
average radius of curvature of less than 88.90 
centimeters (35 inches), as determined under SI 2, 
shall have a label visible to the seated driver. The 
label shall be printed in a type face and color that 
are clear and conspicuous. The label shall state 
the following: 

"USE CROSS VIEW MIRRORS TO VIEW 
PEDESTRIANS WHILE BUS IS STOPPED. DO 
NOT USE THESE MIRRORS TO VIEW TRAF- 
FIC WHILE BUS IS MOVING. IMAGES IN 
SUCH MIRRORS DO NOT ACCURATELY 
SHOW ANOTHER VEHICLE'S LOCATION." 

S9.4 (a) Each image required by S9. 3(a)(1) to be 
visible at the driver's eye location shall be sepa- 
rated from the edge of the effective mirror surface 
of the mirror providing that image by a distance 
of not less than 3 minutes of arc. 

(b) The image required by S9.3(a)(l) of cyl- 
inder P shall meet the following requirements: 

(1) The angular size of the shortest dimen- 
sion of that cylinder's image shall be not less 
than 3 minutes of arc; and 

(2) The angular size of the longest dimension 
of that cylinder's image shall be not less than 
9 minutes of arc. (57 F.R. 57000— December 2, 

1992. Effective: December 2. 1993)] 

510. Requirements for motorcycles. 

S10.1. Each motorcycle shall have either a mirror 
of unit magnification with not less than 12.5 in- 
of reflective surface, or a convex mirror with not 
less than 10 in' of reflective surface and an aver- 
age radius of curvature not less than 20 inches and 
not greater than 60 inches, installed with a stable 
support, and mounted so that the horizontal center 
of the reflective surface is at least 1 1 inches out- 
ward of the longitudinal centerline of the motor- 
cycle. The mirror shall be adjustable by tilting in 
both the horizontal and vertical directions. 

511. Mirror construction. The average reflec- 
tance of any mirror required by this standard shall 
be determined in accordance with SAE Rec- 



PART57I; S 111-3 



(Rev. 12/2/92) 



ommended Practice J964, October 1984. All sin- 
gle reflectance mirrors shall have an average 
reflectance of at least 35 percent. If a miiTor is 
capable of multiple reflectance levels, the mini- 
mum reflectance level in the day mode shall be at 
least 35 percent and the minimum reflectance 
level in the night mode shall be at least 4 percent. 
A multiple reflectance mirror shall either be 
equipped with a means for the driver to adjust the 
mirror to a reflectance level of at least 35 percent 
in the event of electrical failure, or achieve such 
reflectance level automatically in the event of 
electrical failure. 

SI 2. Determination of Radius of Curvature. 

SI 2.1. To determine the average radius of cur- 
vature of a convex mirror, use a 3-point linear 
spherometer, which meets the requirements of 
S12.2., at the 10 test positions shown in Figure 1 
and record the readings for each position. 




Figure 1. 



-Location of Ten Convex Mirror 
Testing Positions 



512.2. The 3-point Hnear spherometer has two 
outer fixed legs 1.5 inches apart and one inner 
movable leg at the midpoint. The spherometer has 
a dial indicator with a scale that can be read 
accurately to 0.0001 inches, with the zero reading 
being a flat surface. 

512.3. The 10 test positions on the image display 
consist of two positions at right angles to each 
other at each of five locations as shown in Figure 
1 . The locations are at the center of the mirror, at 
the left and right ends of a horizontal line that 
bisects the mirror and at the top and bottom ends 
of a vertical line that bisects the mirror. None of 
the readings are within 0.25-inch border on the 
edge of the image display. 

SI 2.4. At each test position, the spherometer is 
held perpendicular to the convex mirror-surface 



and a record is made of the reading on the dial 
indicator to the nearest 0.0001 inch. 

S12.5. Convert the dial reading data for each of 
the 10 test positions to radius of curvature calcula- 
tions using Table I. Consider the change as linear 
for dial readings that fall between two numbers in 
Table I. 

Table I — Conversion Table From Spherometer 
Dial Reading To Radius of Curvature 



Dial reading 


Radius of curvature 
(in inches) 


.00330 


85.2 


.00350 


80.4 


.00374 


75.2 


.00402 


70.0 


.00416 


67.6 


.00432 


65.1 


.00450 


62.5 


.00468 


60.1 


.00476 


59.1 


.00484 


58.1 


.00492 


57.2 


.00502 


56.0 


.00512 


54.9 


.00522 


53.9 


.00536 


52.5 


.00544 


51.7 


.00554 


50.8 


.00566 


49.7 


.00580 


48.5 


.00592 


47.5 


.00606 


46.4 


.00622 


45.2 


.00636 


44.2 


.00654 


43.0 


.00668 


42.1 


.00686 


41.0 


.00694 


40.5 


.00720 


39.1 


.00740 


38.0 


.00760 


37.0 


.00780 


36.1 


.00802 


35.1 


.00822 


34.2 


.00850 


33.1 


.00878 


32.0 


.00906 


31.0 


.00922 


30.5 


.00938 


30.0 


.00960 


29.3 


.00980 


28.7 


.01004 


28.0 


.01022 


27.5 


.01042 


27.0 


.01060 


26.5 


.01080 


26.0 


.01110 


25.3 


.01130 


24.9 


.01170 


24.0 


.01200 


23.4 


.01240 


22.7 


.01280 


22.0 


.01310 


21.5 


.01360 


20.7 


.01400 


20.1 


.01430 


19.7 


.01480 


19.0 


.01540 


18.3 


.01570 


17.9 


.01610 


17.5 


.01650 


17.1 


.01700 


16.6 


.01750 


16.1 


.01800 


15.6 


.01860 


15.1 



(Rev. 12/2/92) 



PARI' 571; S i: 



Table I — Conversion Table From Spherometer 
Dial Reading To Radius of Curvature- 
Continued 



Dial reading 


Radius of curvature 
(in inches) 


.01910 


14.7 


.01980 


14.2 


.02040 


13.8 


.02100 


13'4 


.02160 


13.0 


.02250 


12.5 


.02340 


12.0 


.02450 


11.5 


.02560 


11.0 


.02680 


10.5 


.02810 


10.0 


.02960 


9.5 


.03130 


9.0 


.03310 


8.5 



SI 2.6. Calculate the average radius of curvature 
by adding all 10 radius of curvature calculations 
and dividing by ten. 

512.7. Determine the numerical difference 
between the average radius of curvature and each 
of the 10 individual radius of curvature calcula- 
tions determined in S12.5. 

512.8. Calculate the greatest percentage deviation 
by dividing the greatest numerical difference 
determined in S12.7 by the average radius of cur- 
vature and multiply by 100. 

[S13. School bus mirror test procedures. The 

requirements of S9.1 through S9.4 shall be met 
when the vehicle is tested in accordance with the 
following conditions. 

513.1 The cylinders shall be a color which pro- 
vides a high contrast with the surface on which 
the bus is parked. 

513.2 The cylinders are 0.3048 meters (1 foot) 
high and 0.3048 meters (1 foot) in diameter, 
except for cylinder P which is 0.9114 meters (3 
feet) high and 0.3048 meters (1 foot) in diameter. 

SI 3.3 Place cylinders at locations as specified in 
SI 3.3(a) through SI 3.3(g) and illustrated in Figure 
2. Measure the distances shown in Figure 2 from 
a cylinder to another object from the center of the 
cylinder as viewed from above. 

(a) Place cylinders G, H, and I so that they are 
tangent to a transverse vertical plane tangent to 
the forward-most surface of the bus's front 
bumper. Place cylinders D, E, F so that their cen- 
ters are located in a transverse vertical plane that 



is 1.8288 meters (6 feet) forward of a transverse 
vertical plane passing through the centers of cyl- 
inders G, H, and I. Place cylinders A, B, and C 
so that their centers are located in a transverse 
vertical plane that is 3.6576 meters (12 feet) for- 
ward of the transverse vertical plane passing 
through the centers of cylinders G, H, and I. 

(b) Place cylinders B, E, and H so that their 
centers are in a longitudinal vertical plane that 
passes through the bus's longitudinal centerline. 

(c) Place cylinders A, D, and G so that their 
centers are in a longitudinal vertical plane that is 
tangent to the most outboard edge of the left side 
of the bus's front bumper. 

(d) Place cylinders C, F, and I so that their cen- 
ters are in a longitudinal vertical plane that is tan- 
gent to the most outboard edge of the right side 
of the bus's front bumper. 

(e) Place cylinder J so that its center is in a 
longitudinal vertical plane 0.3048 meters (1 foot) 
to the left of the longitudinal vertical plane pass- 
ing through the centers of cylinders A, D, and G, 
and is in the transverse vertical plane that passes 
through the centerline of the bus's front axle. 

(f) Place cylinder K so that its center is in a 
longitudinal vertical plane 0.3048 meters (1 foot) 
to the right of the longitudinal vertical plane pass- 
ing through the centers of cylinders C, F, and I, 
and is in the transverse vertical plane that passes 
through the centerline of the bus's front axle. 

(g) Place cylinders L, M, N, O, and P so that 
their centers are in the transverse vertical plane 
that passes through the centerline of the bus's rear 
axle. Place cylinder L so that its center is in a 
longitudinal vertical plane that is 1.8288 meters (6 
feet) to the left of the longitudinal vertical plane 
tangent to the bus's most outboard left surface 
(excluding the mirror system). Place cylinder M 
so that its center is in a longitudinal vertical plane 
that is 0.3048 meters (1 foot) to the left of the 
longitudinal vertical plane tangent to the left side 
of the bus. Place cylinder N so that its center is 
in a longitudinal vertical plane that is 0.3048 
meters (1 foot) to the right of the longitudinal 
vertical plane tangent to the right side of the bus. 
Place cylinder O so that its center is in a longitu- 
dinal vertical plane that is 1.8288 meters (6 feet) 
to the right of the longitudinal vertical plane tan- 
gent to the right side of the bus. Place cylinder 
P so that its center is in a longitudinal vertical 
plane that is 3.6576 meters (12 feet) to the right 
of the longitudinal vertical plane tangent to the 



PART 571; S 111-5 



(Rev. 12/2/92) 



right side of the bus. (57 F.R. 57000— December 2, 
1992. Effective: December 2, 1993)] 



16578111(12 ft) 

i.ann(6ft) 




] 0-J048m(lft) I 3.6576ni(12fl 



INTERPRETATION 

(1) When a supplemental mirror is furnished in 
addition to the inside rearview mirror and the 
driver's side outside rearview mirror, the supple- 
mental mirror need not be adjustable from the 
driver's seat. 

(2) The location of the driver's eye reference 
point may be that established in Motor Vehicle 
Safety Standard No. 104, or it may be a nominal 
location appropriate for any 95th percentile male 
driver. 

(3) The horizontal angle is measured from the 
projected eye point, rather than the plane of the 
mirror. 



32 F.R. 2413 
February 3, 1967 



Figure 2.— Location of Test Cylinders for 
School Bus Field-of-View Test 




Figure 3. — Camera Locations for School Bus 
Field-of-View Test 



PARI' 571; S 111-6 



PREAMBLE TO AN AMENDMENT TO FEDERAL MOTOR VEHICLE 

SAFETY STANDARD NO. 121 

Air Brake Systems 

(Docket No. 85-07; Notice 7) 
RIN: 2127-AD-27 



ACTION: Final rule. 



SUMMARY: This rule amends the pneumatic tim- 
ing requirements of Standard No. 121, Air Brake 
Systems, with respect to the control line pressure 
balance. Specifically, the agency is adopting a 
new dynamic test procedure for determining the 
control signal pressure differential. These amend- 
ments are part of a more general rulemaking to 
improve the brake timing balance of combination 
vehicles and partially implement the mandate in 
section 4012 of the Intermodal Surface Transpor- 
tation Efficiency Act (ISTEA) regarding rule- 
making for "improving brake compatibility [and] 
effectiveness of brake timing." 



EFFECTIVE DATE: The amendments become 
effective on August 23, 1992. Vehicles manufac- 
tured before the effective date may comply with 
this rule's amendments, effective September 21, 
1992. 



SUPPLEMENTARY INFORMATION: 

Pneumatic timing is an important factor in air 
brake system performance. The time required for 
a vehicle's service brake chambers to reach a rel- 
atively high pressure level after actuation of the 
brake control by the driver is referred to as 
"pneumatic application time." Since the genera- 
tion of braking force is directly related to the air 
pressure available in the brake chambers, pneu- 
matic application time affects vehicle stopping 
distance. As a general matter, the shorter the 
pneumatic application time, the shorter the 
vehicle's stopping distance. 

The pneumatic application timing can affect the 
stability of combination vehicles. If a trailer's 
brakes apply more slowly on the towing vehicle's 
brakes, the trailer can bump the towing vehicle. 



applying an excessive compressive force on the 
kingpin connecting the trailer to the towing 
vehicle. If the brakes are applied during a turn, 
this force may reduce the stability of the com- 
bination and contribute to a jackknife accident. 

Braking performance is also affected by "pneu- 
matic release timing" (i.e., the time required for 
the pressure in the brake chambers to fall from a 
relatively high pressure to a relatively low pres- 
sure after the driver releases the brake control). If 
a vehicle's wheels lock as the driver is attempting 
to stop, the vehicle will skid. The driver must be 
able to release the brakes immediately to regain 
control of the vehicle in this situation. 

For combination vehicles, pneumatic release 
timing can affect stability. If a towing vehicle's 
brakes release more slowly than the trailer's, 
destabilizing forces may increase at the kingpin. 

Standard No. 121, Air Brake Systems, currently 
specifies certain requirements for pneumatic tim- 
ing. Section S5.3.3 specifies time periods within 
which brake actuation for trucks, buses, and trail- 
ers must occur. Similarly, section S5.3.4 specifies 
time periods within which brake release for these 
vehicles must occur. 

The timing tests for trailers, including trailer 
converter dollies, are conducted with the trailer 
connected to a test rig rather than an actual trac- 
tor. The test rig delivers air to, and releases air 
from, the trailer during the timing test. The timing 
tests for vehicles designed to tow trailers are con- 
ducted with a 50-cubic-inch reservoir connected 
to the rear control line coupling. This reservoir 
represents the control line volume of the towed 
trailer. 

Regulatory Background 
On May 3, 1989, NHTSA published a final 
rule amending Federal Motor Vehicle Safety 
Standard No. 121, Air Brake Systems, to improve 



PART 571: S121— PRE-223 



the timing balance of combination vehicles (54 
FR 13890). 

SNPRM I 

On that same day, NHTSA published a Supple- 
mental Notice of Proposed Rulemaking (SNPRM) 
proposing two further amendments concerning 
pneumatic timing (54 FR 18912). The first pro- 
posal would have required the actuation time at 
the gladhand to be at least as fast as the timing 
at the brake chambers. However, after reviewing 
the comments on this issue, NHTSA decided to 
terminate this portion of the rulemaking because 
the proposed requirement would have reduced 
flexibility in product manufacturing by requiring 
more custom design of vehicles. In addition, the 
costs resulting from such a requirement would not 
have been justified in view of the relatively lim- 
ited safety benefits associated with such a require- 
ment. 

The second proposal would have required that 
the relay booster valves used on towing trailers 
not upset the brake balance of combination 
vehicles. The second proposal was intended to 
allay NHTSA's concern about excessive control 
line pressure differentials in multiple trailer com- 
binations. Another concern was that pressure dif- 
ferentials, which could be caused by relay booster 
valves with overly high crack pressures (i.e., the 
pressure at which a booster relay valve opens), 
could create situations in which the brakes of 
only the towing trailer were actuated. For exam- 
ple, if the crack pressure were too high, the relay 
booster valve would not open during mild brak- 
ing, and the brakes of the towed trailer would not 
be actuated. 

NHTSA proposed to require that, in all situa- 
tions in which the pressure at the input coupling 
is steady (or is increasing or decreasing at a rate 
of 10 psi per minute or less), the pressure dif- 
ferential between the control line gladhand at the 
front of a towing trailer and the control line glad- 
hand at the rear of the trailer not exceed 1.0 psi 
at input pressures between 5.0 and 20.0 psi, and 
not exceed 2.0 psi at input pressures above 20.0 
psi. The agency believed that the requirement 
would ensure that the brakes of both the towing 
trailer and the towed trailer would receive the 
same signal. 

SNPRM II 

After reviewing the comments to the first 
SNPRM, the agency published a second supple- 



mental notice of proposed rulemaking (SNPRM) 
on March 15, 1991 (56 FR 11150). As mentioned 
above, the agency decided to terminate the por- i^^ 
tion of the rulemaking about gladhand actuation ^* 
timing. As for the proposal about control line 
pressure differential, NHTSA decided to propose 
modified requirements. 

The commenters generally agreed in theory that 
control line pressure differential should be con- 
trolled. However, commenters stated that the pro- 
posed requirements were inappropriate. Bendix 
Heavy Vehicle Systems Group (Bendix) stated 
that the proposed 10 psi per minute rate of pres- 
sure change was extremely slow and would be 
difficult to maintain over a wide pressure range. 
Bendix also stated that the proposed rate was not 
representative of normal pressure changes that 
occur during braking. 

Bendix suggested an alternative test procedure 
using two specific test orifices with fixed diame- 
ters and thickness to control flow rates. Bendix 
recommended that the test orifice sizes be set at 
0.0180 inches diameter for application timing and 
0.0292 inches diameter for release timing. Bendix 
believed that these diameters would produce 
brake pressure rates that are consistent with lower 
limit applications, such as those required for ^ 
maintaining vehicle speed on a five percent grade. 
Bendix recommended four psi per second for 
application and release testing, a rate substantially 
faster than the one proposed by NHTSA in the 
first SNPRM, but closer to rates seen in actual 
service applications. Bendix also suggested that 
the testing procedure for detemiining the control 
signal pressure differential on towing trailers and 
dollies use either of the current Standard No. 121 
trailer test rigs and an orifice fixture, coupled 
between the control line gladhand of the trailer 
test rig and the control line input coupling of the 
vehicle to be tested. 

After reviewing Bendix's suggested pressure 
differential test, NHTSA decided to propose a 
simplified test procedure that would use only one 
metering orifice, i.e., the smaller of the two ori- 
fices suggested by Bendix. While Bendix claimed 
that the use of two orifices would result in the 
same pressure change rate for both apply and 
release, NHTSA did not believe that monitoring 
the same pressure change rate was necessary. The 
agency believed that using one rather than two ^ 
orifices would avoid the very fast or very slow " 
pressure rate rises that could be problematic. 



PART 571; S121— PRE-224 



NHTSA anticipated that the apply rate would 
approximate four psi per second, but the release 
rate would be somewhat slower. 

The second SNPRM explained that the pro- 
posed pressure differential test slowly "sweeps" 
the pressure across the full range of operating 
pressures, thus enabling the person conducting the 
test to check the differential level. The orifice 
restricts the flow from the trailer test rig and 
slows the pressure rise and decay rate. The ability 
to "sweep" the pressure slowly makes it 
unnecessary to stop and hold the pressure con- 
stant. If the pressure is changed too rapidly, the 
steady state case (i.e., when brake pressure is 
being held steady after application of the brakes) 
is not evaluated and pressure differentials caused 
by air flow through the control lines, instead of 
valve characteristics, are introduced. 

NHTSA tentatively concluded that the proposal 
concerning control line pressure differential was 
necessary to meet the need for motor vehicle 
safety. NHTSA believed that some trailer manu- 
facturers would install relay valves at the rear of 
the trailers in the control lines upstream of the 
towing gladhands to "boost" the control signal. 
This would result in a significant margin of 
compliance with the new brake timing require- 
ments for towing trailers established by NHTSA 
in the May 3, 1989 final rule. 

In response to the second SNPRM, the agency 
received four comments. They were submitted by 
Midland-Grau, Bendix Heavy Vehicle Systems, 
the Truck Trailer Manufacturers Association 
(TTMA), and Mr. Robert Crail, a consultant. The 
agency has considered the points raised in the 
comments in developing this final rule. The com- 
menters' significant points are addressed below, 
along with the agency's response to the com- 
ments. 

Agency's Determination 
1 . Safety Need 

Midland-Grau questioned the safety need for 
the proposal, stating that "Since there is no 
identified relationship between the control line 
pressure and brake force exerted, there appears to 
be no justification for the great efforts needed to 
achieve tightly tracking control line pressures." 

NHTSA agrees with Midland-Grau that there is 
no absolute relationship between control line pres- 
sure and brake force. Nevertheless, by ensuring 
that the pressures will be constant as they are 



passed to other vehicles in combinations, this 
rulemaking will alleviate one significant source of 
combination vehicle brake imbalance. Therefore, 
the commenler's concern about the nonexistence 
of such a relationship has no bearing on the 
imbalance problem. 

NHTSA notes that this rulemaking action to 
add requirements for control line pressure balance 
was intended to be a small but important part of 
the general rulemaking package regarding timing 
changes (see docket No. 85-07; Notice 3). There- 
fore, in detennining the safety benefits derived 
from the control line pressure amendment, the 
safety benefits obtained from the more general 
timing amendments should be considered to some 
extent. The agency continues to believe that the 
amendment about control line pressure should be 
adopted because, without this provision, an imbal- 
ance problem could exist if a manufacturer 
installed relay booster valves which speeded up 
the timing to meet the new timing requirements. 

The amendment is designed to ensure that the 
control signal "passes" through a towing trailer 
or dolly without being altered along the way. 
Because the control signal passes through 
unaltered, each vehicle in the combination unit 
receives the same brake control signal (i.e., by 
keeping the control signal at the same level, each 
vehicle in a combination has a comparable brak- 
ing performance). The agency acknowledges that 
Standard No. 121 does not specifically address 
brake force as a function of control pressure. 
Nevertheless, the Society of Automotive Engi- 
neers (SAE) developed SAE Recommended Prac- 
tice J 1854 and Test Procedure J 1505 to allay con- 
cerns about incompatibility. The agency believes 
that this rulemaking will act in conjunction with 
SAE J 1854 to improve compatibility between 
vehicles. 

2. Test Procedure 

The second SNPRM proposed a dynamic test 
procedure in which pressure differential is evalu- 
ated using a single metering orifice. TTMA and 
Mr. Crail favored a test procedure measuring 
static conditions. TTMA believed that such a test 
procedure would be more similar to actual brak- 
ing and would be less costly. 

Notwithstanding these comments, the agency 
favors a dynamic test procedure which slowly 
sweeps across the full range of pressures. The 
agency notes that NHTSA's Vehicle Research and 



PART 571; SI21— PRE-225 



Test Center (VRTC) conducted tests which 
indicated that the proposed dynamic test appro- 
priately evaluated control pressure differential. 
These tests were designed to measure the control 
line pressure valve's influence on the control line 
pressure to ensure that the pressure is not ampli- 
fied. When such pressure is amplified, the pres- 
sure may not properly "bleed" back to the stable 
level, and thus adversely affect the timing among 
vehicles in a combination. The testing compared 
the pressure between the gladhand at the front of 
a towing trailer and the gladhand at the rear. The 
agency does not believe that the pressure differen- 
tial problem which may arise through increased 
use of relay booster valves can be controlled with 
a static pressure test. Performing the necessary 
testing is technologically sensitive because the 
pressure between the gladhand in front of a tow- 
ing trailer must be compared with the pressure at 
the rear gladhand. Given that the test sequence of 
events between the front gladhand and the rear 
gladhand occurs very rapidly and at pressure dif- 
ferentials too small for human observers to record 
the event accurately, the devices recommended by 
some commenters would be incapable of measur- 
ing such an intricate situation. 

Mr. Crail commented that tolerances are needed 
in the test requirements, claiming that it is impos- 
sible to measure pressure exactly. He indicated 
that pressure accuracy within a range of ± 0.25 
psi would be appropriate. 

NHTSA notes that the agency generally does 
not specify tolerances in a requirement since a 
minimum or maximum value does not need a 
tolerance. The test values specified in the 
changes, as adopted, are one-sided maximum 
specifications in that the pressure differential from 
5 to 20 psi cannot exceed 1 psi and at pressures 
over 20 psi cannot exceed 2 psi. Accordingly, the 
agency has determined that tolerances in the 
specified pressures are not necessary. 

3. Cost 

TTMA and Mr. Crail believed that the amend- 
ment's costs would be excessive. TTMA was con- 
cerned that the proposed test procedure would 
require trailer manufacturers to purchase expen- 
sive equipment such as transducers and recording 
equipment costing as much as $6,000. In contrast, 
it claimed that the equipment necessary for the 
static test procedure it favors would cost about 
$300 per manufacturer. Mr. Crail stated that the 



total cost of the static test would be less than 
$900, as compared to approximately $6,000 to 
conduct the test proposed by the agency. Simi- 
larly, Midland-Grau stated that the proposed 
requirements were impractical and unjustifiable. 

After conducting its own review, NHTSA 
believes that the costs associated with the test 
equipment are reasonable and well below the 
costs estimated by the commenters. The agency 
notes that most trailer manufacturers already own 
the most expensive portion of this test equipment 
for conducting timing tests (i.e., the data recorder/ 
power supply/signal conditioning apparatus), and 
that the mini-tractor test rigs that are currently 
used in compliance testing with Standard No. 121 
could be readily upgraded to check for pressure 
differentials for an additional cost of $300. Of 
this cost figure, $100 would cover the hose, glad- 
hands, and air flow restrictor and $200 would 
cover the cost of upgrading the software of the 
test rig. NHTSA notes that the practical effects of 
these requirements are limited to only those trailer 
manufacturers who build towing trailers (i.e., 
trailers used in doubles or triples operations). 
Such towing trailers currently constitute a very 
small percentage of the trailer market. 

4. Effective Date 

The NPRM proposed an effective date of one 
year after the final rule's publication. Bendix 
requested that the rule become effective as soon 
as possible, claiming that this would limit the 
number of vehicles designed to comply with 
Notice 3 that would have an undesirable control 
pressure differential. 

After reviewing the comments, the agency 
believes that optional compliance with the control 
pressure differential amendments should be per- 
mitted beginning 30 days after the final rule's 
publication. The agency believes that allowing 
earlier optional compliance will reduce the num- 
ber of vehicles that may be built with excessive 
pressure differentials. Mandatory compliance will 
still be effective one year after publication of the 
final rule. 

This final rule does not have any retroactive 
effect. Under section 103(d) of the National Traf- 
fic and Motor Vehicle Safety Act (15 U.S.C. 
1392(d)), whenever a Federal motor vehicle safety 
standard is in effect, a state may not adopt or 
maintain a safety standard applicable to the same 
aspect of performance which is not identical to 



PART 571; S121— PRE-226 



the Federal standard. Section 105 of the Act (15 
U.S.C. 1394) sets forth a procedure for judicial 
review of final rules establishing, amending, or 
revoking Federal motor vehicle safety standards. 
That section does not require submission of a 
petition for reconsideration or other administrative 
proceedings before parties may file suit in court. 
In consideration of the foregoing, 49 CFR Part 
57 1 is amended as follows: 

1. The authority citation for Part 571 continues 
to read as follows: 

Authority: 15 U.S.C. 1392, 1401, 1403, 1407; 
delegation of authority at 49 CFR 1.50. 
§571.121 [Amended] 

2. S5.3.5 is added to §571.121 to read as fol- 
lows: 

S5.3.5 Control signal pressure differential — 
converter dollies and trailers designed to tow 
another vehicle equipped with air brakes. 

(a) For a trailer manufactured on or after 
[INSERT DATE ONE YEAR AFTER PUBLICA- 
TION OF THE FINAL RULE] and designed to 
tow another vehicle equipped with air brakes, the 
pressure differential between the control line input 
coupling and a 50 cubic inch test reservoir 
attached to the control line output coupling shall 
not exceed the values specified in S5. 3.5(a)(1) 
and (2) under the conditions specified in 
S5.3.5(b)(l) through (4)— 



(1) 1 p.s.i. at all input pressures equal to or 
greater than 5 p.s.i., but not greater than 20 p.s.i.; 
and 

(2) 2 p.s.i. at all input pressures greater than 
20 p.s.i. 

(b) The requirements in S5.3.5(a) shall be 
met — 

(1) When the pressure at the input coupling 
is steady, increasing or decreasing; 

(2) When air is applied to or released from 
the control line input coupling using the trailer 
test rig shown in Figure 1; 

(3) With a fixed orifice consisting of a 
0.0180 inch diameter hole (no. 77 drill bit) in a 
0.032 inch thick disc installed in the control line 
between the trailer test rig coupling and the 
vehicle's control line input coupling; and 

(4) Operating the trailer test rig in the same 
manner and under the same conditions as it is 
operated during testing to measure brake actuation 
and release times, as specified in S5.3.3 and 
S5.3.4, except for the installation of the orifice in 
the control line to restrict airflow rate. 

Issued on August 18, 1992. 

Howard M. Smolkin 
Executive Director 

57 F.R. 37902 
August 21, 1992 



PART 571; S121—PRE-227 



PREAMBLE TO AN AMENDMENT TO FEDERAL MOTOR VEHICLE 
SAFETY STANDARD NO. 121 

Air Brake Systems 

(Docket No. 91-21; Notice 2) 
RIN: 2127-AD-34 



ACTION: Final rule. 

SUMMARY: This rule amends Federal Motor 
Vehicle Safety Standard No. 121, Air Brake Sys- 
tems, to require automatic brake adjusters on all 
air-braked vehicles and adjustment indicators on 
air-braked vehicles with external adjustment 
mechanisms. This rule also amends Standard No. 
105, Hydraulic Brake Systems, to require auto- 
matic brake adjusters on vehicles with hydraulic 
brake systems. However, the rule does not require 
adjustment indicators on hydraulically-braked 
vehicles because there do not appear to be signifi- 
cant problems with monitoring automatic brake 
adjusters on such vehicles. These amendments 
should improve the braking performance of 
vehicles by ensuring that their brakes are properly 
adjusted. 

EFFECTIVE DATES: The amendments to Stand- 
ard No. 105 become effective October 20, 1993. 

The amendments to Standard No. 121 become 
effective October 20, 1994. 

SUPPLEMENTARY INFORMATION: 

Background 

General Information 
Proper brake adjustment is critical for maintain- 
ing safe stopping performance. Devices known as 
automatic brake adjusters automatically maintain 
proper brake adjustment, thus eliminating the 
need for frequent inspection and manual adjust- 
ment of the brakes. Automatic brake adjusters 
have been used on passenger cars and light trucks 
since the early 1960's and have been standard 
equipment on all such vehicles sold in recent 
years in the United States. In addition, the vast 
majority of medium and heavy duty vehicles with 



hydraulic brake systems have automatic brake 
adjusters. Automatic brake adjusters were intro- 
duced for use on heavy duty air-braked vehicles 
in the early 1960's and are widely used today. 
The installation rates of automatic brake adjusters 
by manufacturers of heavy duty air-braked 
vehicles range from 30 to 100 percent of their 
fleets. 

Safety Need and Practicability of Automatic 
Adjustment Devices 

Notwithstanding the importance of proper brake 
adjustment for maintaining safe stopping perform- 
ance, numerous studies have shown that brake 
adjustment is not being maintained on some air- 
braked medium and heavy duty vehicles that are 
not equipped with automatic brake adjusters. (See 
Automatic Slack Adjusters for Heavy Vehicle Air 
Brake Systems, DOT HS 807 724, February 
1991.) When brakes are under-adjusted, stopping 
ability is reduced and the probability of a crash 
is increased. When brakes are over-adjusted, 
maintenance costs and the possibility of a crash 
are increased as a result of excessive lining wear, 
wheel lock, or brake drum cracking. Such 
improper brake adjustment contributes to a 
significant number of crashes, including those in 
which vehicles are unable to stop in time and 
those in which there are "runaways" on steep 
mountain grades. 

As detailed in the notice of proposed rule- 
making (NPRM) for this rulemaking (56 FR 
20396, May 3, 1991), several studies highlight the 
problems associated with improper brake adjust- 
ment, especially on air-braked vehicles. These 
studies include the Office of Technology Assess- 
ment's (OTA's) September 1988 report Gearing 
Up for Safety, NHTSA's March 1987 Heavy 
Truck Safety Study Report to Congress, the 
National Transportation Safety Board's investiga- 



PART 571: S121— PRE-229 



tions of heavy truck crashes, and a Federal High- 
way Administration study. 

Based on the above-mentioned concerns, the 
National Transportation Safety Board recom- 
mended that NHTSA develop a Federal Motor 
Vehicle Safety Standard requiring all newly 
manufactured commercial vehicles to have equip- 
ment ensuring that brakes are always properly 
adjusted. 

Automatic brake adjusters are now used on 
approximately 60 percent of new medium and 
heavy duty vehicles with air brakes. However, 
one major, and a number of smaller vehicle 
manufacturers, do not provide automatic brake 
adjusters as standard equipment, and many pur- 
chasers do not order them as optional equipment. 
NHTSA believes that automatic brake adjuster 
use has stabilized at about the current 60 percent 
level. 

NHTSA has conducted a large-scale fleet 
evaluation to assess the performance and reliabil- 
ity of automatic brake adjusters, as compared to 
manual adjusters on heavy commercial vehicles 
with S-cam air brakes. NHTSA collected brake 
adjustment data from several hundred fleet 
vehicles equipped with automatic and manual 
brake adjusters for approximately five years. The 
conclusions regarding the fleet examination are 
detailed in the NPRM. Among the principal 
conclusions were that: 

• Automatic brake adjusters generally maintained 
brake adjustments within the limits specified by 
the vehicle manufacturer. The medium percent- 
age of out-of-adjustment brakes for the fleet 
applications was about four percent. This rep- 
resents a far lower out-of-adjustment rate than 
is commonly found in roadside check studies of 
brake adjustment for manually-adjusted air 
brakes. 

• In the most successful applications, automatic 
brake adjusters consistently exhibited out-of- 
adjustment percentages of less than one per- 
cent. Thus, automatic brake adjusters dem- 
onstrated the potential for very effective 
performance levels. 

• The incidence of brake over-adjustment with 
automatically-adjusted brakes was low. In the 
fleet test, there was no case of an automatic 
brake adjuster over-adjusting a brake enough to 
cause brake over-heating, wheel lockup, or 
excessive brake lining wear. 



Automatic Adjusters and Indicators on Air Brake 
Systems 

There are three principal types of air-braked 
systems used in this country: 1) S-cam actuators, 
2) wedge type actuators, and 3) disc brakes. For 
S-cam brakes, which comprise about 95 percent 
of air-brake systems, two major types of auto- 
matic brake adjusters are available. One adjusts 
on the basis of actual shoe-to-drum clearance. The 
other adjusts on the basis of the air chamber push 
rod stroke. All wedge type brakes, which com- 
prise about three percent of the market, have an 
interna! automatic adjustment mechanism. As for 
disc brakes which comprise about two percent of 
air-brake systems, some have external self-adjust- 
ing mechanisms, while others have internal 
adjustment features. The external adjustment 
mechanism of an air disc brake system operates 
similarly to those on S-cam brakes. 

Brake adjustment indicators improve brake 
adjustment by increasing the convenience of 
checking brake adjusters and their proper func- 
tioning. Without brake adjustment indicators, 
measuring brake adjustment requires following a 
laborious and time-consuming manual procedure 
in which the push rod length must be measured 
before and during brake application. The proce- 
dure is especially difficult for brake chambers 
located at positions under the vehicle that are dif- 
ficult to reach. Also, a person checking brake 
adjustment must know the specific adjustment 
data for each chamber because some manufactur- 
ers have slightly different stroke lengths for the 
same size chamber. The procedure is also com- 
plicated because the chamber's make and model 
may be difficult to identify when it is covered 
with road dirt and conosion. 

Several types of brake adjustment indicators are 
currently available. One type involves air brake 
chambers with paint markings on push rods that 
indicate the level of adjustment. However, such 
markings may not be useful in certain applica- 
tions (e.g., with wedge brakes when the push rod 
is enclosed in a sleeve and with S-cam brakes 
having push rods with protective rubber boots). A 
second type of brake adjustment indicator is 
installed by inserting a guide arm and sliding 
stem assembly into a small hole in the air booster 
can. A third method involves attaching a hose 
clamp to the air chamber push rod to mark the 
fully adjusted brake position relative to the air 
chamber housing. To check the brake adjustment. 



PART 571: S121— PRE-230 



3 



the space between the air chamber housing and 
hose clamp is compared with a bar gauge. 

Notice of Proposed Rulemaking 

On May 3, 1991, NHTSA published an NPRM 
in which the agency proposed to amend Standard 
No. 121 to require automatic brake adjusters and 
adjustment indicators on vehicles with air brake 
systems. (56 FR 20396) The NPRM also pro- 
posed to amend Standard No. 105 to require auto- 
matic brake adjusters on vehicles with hydraulic 
brake systems. NHTSA decided not to propose 
requiring adjustment indicators on hydraulically- 
braked vehicles because the agency believed that 
there were no significant problems with automatic 
brake adjusters for these vehicles or with check- 
ing the adjustment of such systems. 

Among the issues discussed in the NPRM were 
(1) the need to require automatic brake adjusters 
in passenger cars and other hydraulically braked 
vehicles, (2) specific provisions in the proposed 
language to require automatic brake adjusters on 
passenger cars, (3) the need for automatic brake 
adjusters on air-braked vehicles to correct for 
both under and over-adjustment, (4) the apparent 
absence of a need for automatic adjustment 
indicators for hydraulically braked vehicles, (5) 
visibility requirements for adjustment indicators 
on air-braked vehicles, (6) the necessary leadtime 
for the proposal, and (7) the costs associated with 
the rulemaking. 

Comments to the NPRM and the Agency's 
Response 

NHTSA received about 35 comments in 
response to the NPRM. These were from vehicle 
manufacturers, brake manufacturers, manufactur- 
ers of brake adjusters and adjustment indicators, 
heavy vehicle users, trade associations, and oth- 
ers. The majority of commenters generally agreed 
with the proposal to require brake adjusters on 
both hydraulic and air-braked vehicles and to 
require adjustment indicators on air-braked 
vehicles. In addition, commenters addressed spe- 
cific matters in the proposed regulation, including 
the issues of over-adjustment, visibility require- 
ments, and other provisions in the proposed regu- 
latory text. 

The agency has considered the points raised by 
the commenters in developing the final rule. The 
agency's discussion of the more significant com- 
ments and other relevant information is set forth 



below. The notice first addresses issues about 
automatic adjusters and indicators on vehicles 
equipped with air brakes because the safety prob- 
lem primarily involves, and consequently the 
agency's rulemaking efforts focus on. these 
vehicles. The notice then discusses adjustment 
devices on hydraulically-braked vehicles. 

Ail- Braked Vehicles 
1 . General Considerations 

As explained above, the safety problem with 
out-of-adjustment brakes primarily involves air- 
braked vehicles. Accordingly, the agency's rule- 
making efforts have focused on requiring auto- 
matic adjusters and adjustment indicators on such 
vehicles. 

In response to the NPRM's proposal to require 
automatic adjusters on air-braked vehicles, all but 
one commenter addressing this issue supported 
requiring automatic adjusters on air-braked 
vehicles. Those supporting the rulemaking 
included the American Trucking Associations 
(ATA), Truck Trailer Manufacturers Association 
(TTMA), General Motors (GM), Ford, and Advo- 
cates for Highway and Auto Safety (AHAS). 
AHAS stated that the amendments would mitigate 
the extent and severity of fatal and injury produc- 
ing accidents. Only one commenter, Mr. Robert 
Grail, a brake consuhant, disputed the need for 
and effectiveness of automatic adjusters on air- 
braked vehicles. Mr. Grail stated that automatic 
adjusters are not accurate enough to be mandated, 
citing raw data about automatic slack adjusters. 

Based on the comments and other available 
information, NHTSA has determined that requir- 
ing automatic adjusters on air-braked vehicles will 
improve the brake performance of these vehicles. 
As the NPRM explained, out-of-adjustment brakes 
pose a significant safety problem that could be 
alleviated by requiring automatic brake adjusters. 
The agency notes that Mr. Grail's critical com- 
ments were based, in part, on raw data gathered 
from unscreened sources and uncontrolled test 
conditions. Therefore, his conclusions based on 
the data are questionable. While NHTSA 
acknowledges that older brake adjuster designs 
may not perform as well as properly maintained 
manual adjusters, the new generation of currently 
produced automatic adjusters provide superior 
brake adjustment. In addition, even the previous 
generation of automatic brake adjusters are often 



PART 571: S121— PRE-231 



superior to manual adjusters because some owners 
of vehicles with manual adjusters do not take the 
time to properly adjust or otherwise properly 
maintain their brakes. 

2. Proposed Regulatory Text 

The NPRM proposed amending Standard No. 
121 to require all vehicles with air brakes to be 
equipped with automatic adjusters. Specifically, 
the NPRM proposed that the Standard be amend- 
ed to require these devices on trucks, buses, and 
trailers, as follows: 

"Each vehicle shall be equipped with a serv- 
ice brake system acting on all wheels. Wear of 
the service brakes shall be compensated for by 
means of a system of automatic adjustment, 
which maintains brake adjustment within the 
manufacturer's recommended adjustment limits. 
The condition of service brake adjustment shall 
be provided by a brake adjustment indicator 
that is discernible when viewed with 20/40 
vision, using an ordinary flashlight with two D- 
cell batteries from a position 8 feet away on 
the adjacent pavement surface. The brake 
adjustment indicator shall be capable of 
displaying the service brake adjustment condi- 
tions of: under-adjustment, over-adjustment, 
and fully adjusted within the manufacturer's 
specified limits. 

Commenters addressed various aspects of the 
proposed regulatory text, including specifying that 
brake adjustment be maintained within the manu- 
facturer's recommended adjustment limits, having 
adjusters correct for under and over adjustment, 
having indicators display the conditions of under, 
over, and full adjustment, and having visibility 
requirements. Along with the comments address- 
ing each of these considerations, the agency's 
response to the comments is presented below. 

a. Brake Adjustment withiii Manufacturer' s 
Recommended Adjustment Limits 

As explained above, the NPRM proposed that 
brake adjustment would have to be maintained 
"within the manufacturer's recommended adjust- 
ment limits." The agency had tentatively believed 
that requiring adjustment within the manufactur- 
er's recommended adjustment limits would pro- 
vide a more specific performance requirement. 

Several commenters, including White GMC/ 
Volvo, GM, Ford, Midland-Grau, and a brake 
indicator manufacturer, criticized the proposal to 
require maintaining brake adjustment within the 



manufacturer's recommended adjustment limits. 
These commenters believed that the proposal was 
unnecessary, ambiguous, and would unreasonably J^ 
burden manufacturers. GM and Ford stated that 
the proposal was potentially ambiguous since 
determining what "maintaining brake adjust- 
ment" means could be interpreted several ways. 
Accordingly, these commenters believed that 
some compliance test would be necessary if the 
agency adopted this provision. White GMC/ 
Volvo, GM, and Ford believed that the proposal 
might be interpreted as requiring the manufacturer 
to be responsible for brake adjustment throughout 
the vehicle's life, even though the manufacturer is 
typically responsible for compliance only until the 
first consumer purchase. In addition, some com- 
menters were concerned that the proposal did not 
specify an objective measure about the proper 
level of adjustment. This consideration led Mid- 
land-Grau to recommend that the standard incor- 
porate the Federal Highway Administration's 
requirements in appendix G to subchapter B of 
Chapter III, Title 49, Code of Federal Regula- 
tions. FHWA, based on input from the Commer- 
cial Vehicle Safety Alliance and brake chamber 
manufacturers, has established a set of brake ^ 
adjustment tables that are published in the North Q 
American Uniform Vehicle Out-of-Service Cri- 
teria. The States rely on these roadside inspection 
tables to place a vehicle out of service if the 
adjustment limits are exceeded. 

After reviewing the comments and the available 
information, NHTSA has determined that the final 
rule should not include a reference to maintaining 
adjustment within the manufacturer's rec- 
ommended limits. The agency agrees with com- 
menters that such a provision would not provide 
any significant safety benefits but might cause 
unnecessary complications and confusion. In 
terms of safety benefits, the final rule addresses 
the most important issue by requiring each 
vehicle to be equipped with a service brake sys- 
tem including means for automatic adjustment to 
compensate for wear of the system. The reference 
to the manufacturer's adjustment limits would 
have been superfluous and potentially confusing. 
Nevertheless, as explained below, the agency has 
decided to reference the FHWA's regulations 
about "Vehicle Out-of-Service Criteria." By not 
including reference to maintaining adjustment M 
based on the manufacturer's recommendations, ^ 
this amendment is consistent with the proposed 



PART 571: S121— PRE-232 



requirement about brake adjustment in Standard 
No. 135, Passenger Car Brake Systems. (56 FR 

\ 30528. July 3. 1991.) Accordingly, the final rule 

^ specifies that "Wear of the service brakes shall 
be compensated for by means of a system of 
automatic adjustment," without reference to a 
manufacturer's adjustment limits. The agency 
notes that there is no objective criteria as to what 
constitutes "maintains adjustment." In addition, 
as a general rule, the agency does not establish 
extended durability testing. The agency believes 
that to require that the adjustment be maintained 
throughout the lifetime of the vehicle is unrealis- 
tic, dependent upon the vehicle's exposure, and 
beyond the scope of NHTSA's authority. 

As for Midland-Grau's recommendation to use 
FHWA's regulations for "Driver Out-of-Service 
Criteria" for brake adjustment, NHTSA has 
decided to reference these provisions in Standard 
No. 121 because they are relevant to in-use heavy 
truck operation regulated by FHWA. Because 
amendments to Standard No. 121 require the use 
of brake adjustment indicators which require the 
display of underadjustment, a reference to adjust- 
ment limits is necessary. Those limits are speci- 

i fied in Appendix G to Subchapter B of Chapter 

' III, 49 CFR Parts 200 to 399. 

b. Brake Over-adjustment and Under-adjust- 
ment 

The NPRM tentatively concluded that auto- 
matic brake adjusters should have the capability 
of correcting for both under and over-adjustment. 
The NPRM also proposed that a brake adjustment 
indicator be capable of displaying the brake 
adjustment conditions of under-adjustment, over- 
adjustment, and fully adjusted. The notice 
requested comments about whether these require- 
ments were feasible and whether they should be 
specified in the regulatory text. 

Twelve commenters, primarily heavy brake and 
vehicle manufacturers, opposed requiring brake 
adjusters to correct for over-adjustment. These 
commenters also opposed requiring the brake 
adjustment indicators to identify the over-adjusted 
and fully adjusted conditions. User groups, such 
as the Owner-operator Independent Drivers 
Association supported, these proposals. Navistar, 
Haldex, Bendix, Midland-Grau, Rockwell, Ford, 
k\ the MVMA, Chrysler, Eaton, and the ATA 
' believed that requiring the device to control for 
over-adjustment and having the adjustment indica- 



tor identify this condition were unnecessary and 
impracticable. MVMA stated that the incidence of 
over- adjustment is very infrequent and poses a 
minimal risk to safety. In addition, several manu- 
facturers explained that the condition of over- 
adjustment can be ascertained by excessive wear, 
abuse of the equipment, and, in extreme cases, 
smoke. The commenters also stated that the pro- 
posal was impracticable because there was no 
current technology that reliably indicates the over- 
adjusted condition. After reviewing the comments 
and available information, NHTSA concludes that 
requiring brake adjusters to correct for over- 
adjustment and having adjustment indicators show 
the over-adjusted and fully-adjusted conditions are 
unnecessary for safety and would be impractica- 
ble. In terms of the safety need, the fleet evalua- 
tion cited in the NPRM concluded that the 
incidence of brake over-adjustment was extremely 
low. NHTSA further notes that potential problems 
associated with over-adjustment will not be 
significant. The driver typically will be aware of 
over-adjustment because the brake system will 
drag and may begin to smoke. In terms of prac- 
ticability, the NPRM's tentative determination 
about the availability of automatic brake adjusters 
to correct for over-adjustment appears to be 
inconsistent with the cunent state of brake tech- 
nology. The agency now agrees with the com- 
ments that regulating over-adjustment would be 
impracticable given that such devices are not 
readily available. Based on the above, the final 
rule does not require brake adjusters to correct for 
over-adjustment and does not require the adjust- 
ment indicators to show the over-adjusted and 
fully-adjusted conditions. 

As for the condition of under-adjustment, most 
commenters, including Rockwell, MVMA, Ford, 
and GM believed that the agency should intro- 
duce requirements to prevent this brake condition. 
MVMA stated that the primary motivation and 
safety benefit underlying automatic brake adjust- 
ers is to minimize the incidence of under-adjust- 
ment. 

After reviewing the comments and the available 
information, NHTSA has decided to adopt provi- 
sions requiring brake adjusters to correct for the 
condition of service brake under-adjustment and 
have a device that indicates the under-adjusted 
condition. The agency agrees with the com- 
menters that under adjustment poses a significant 
risk to safety. In addition, NHTSA believes that 



PART 571; SI 



this requirement is practicable since there cur- 
rently are several devices that are capable of 
indicating the under-adjusted condition. Accord- 
ingly, Sections 5.1.8 and S5.2.2 are amended to 
read, in relevant part, '"(b) Brake indicator. ...the 
condition of service brake under-adjustment shall 
be provided by a brake adjustment indicator ..."' 

c. Visibilit}' Requirements for Brake Adjusters 

The NPRM proposed that the brake adjustment 
indicator be discernible when viewed with 20/40 
vision, using an ordinary flashlight with two D- 
cell batteries from a position at least eight feet 
away on the adjacent pavement surface. The 
agency believed that these visibility requirements 
would allow a person to check brake adjustment 
without having to crawl under the vehicle. 

Commenters offered various views about the 
proposed visibility requirements. Manufacturers of 
aftermarket add-on indicators favored the pro- 
posal, while vehicle manufacturers and custom 
builders objected. Users of brake equipment 
offered mixed views. 

Several commenters, including Mack, Navistar, 
GM, the National Truck Equipment Association 
(NTEA), Haldex, the Truck Trailer Manufacturers 
Association (TTMA), and Flxible stated that the 
proposed visibility requirements were impractica- 
ble, especially for those vehicle configurations in 
which the line of sight to the air brake chambers 
is obscured, hi many vehicles, including buses, 
beverage haulers, walk-in vans, ambulances, low- 
bed trucks, utility trailers, and tank-trucks, the 
brake adjustment indicator may only be inspected 
by crawling under a vehicle. Mack explained that 
many vehicle configurations make it difficult or 
impossible to view the chamber from eight feet 
away because brake chambers are frequently 
located in positions that are obscured by tires, 
hoods, and other vehicle components. In addition, 
Rockwell stated that in-service environmental fac- 
tors such as mud, salt, and grease would prevent 
the reading of the adjustment indicator unless the 
chamber were wiped off. 

These practicability concerns with the proposed 
visibility requirements led commenters to rec- 
ommend modifying the proposal. GM rec- 
ommended a simplified requirement in which the 
indicator would have to be discernible when 
viewed with 20/40 vision from outside or the 
underside of the vehicle. Ford suggested that the 
visibility requirement allow inspection from either 
side of or under the vehicle. 



After reviewing the comments, NHTSA has 
decided not to adopt the detailed visibility pro- 
posal because the requirement would raise signifi- |^ 
cant practicability problems. The agency notes 
that the proposed eight-foot requirement would 
necessitate extensive redesign of certain vehicle 
configurations such as drop floor and moving 
vans. In addition, the proposed visibility require- 
ment would be impracticable for evaluating brake 
adjusters that have been covered by road contami- 
nants such as dirt, grime, and snow. NHTSA 
believes that by not adopting the eight-foot view- 
ing requirement, the standard will encourage 
closer hands-on inspection of the equipment. 
Based on the above considerations, the agency 
has decided not to require that the adjustment 
indicator be readable at a distance of eight feet. 
The visibility provision now states that "the 
condition of service brake under-adjustment shall 
be provided by a brake adjustment indicator that 
is discernible when viewed with 20/40 vision 
from a location adjacent to or underneath the 
vehicle." 

d. Vehicle Type 

The NPRM proposed that all air-braked 
vehicles be equipped with an adjustment indica- ^ 
tor, regardless of brake system type. The NPRM 
explained that there were three principal types of 
air brake systems: S cam brakes which account 
for 95 percent of the brake market; wedge type 
brakes, three percent of the market; and disc 
brakes, two percent of the market. While S cam 
brakes have external adjustment mechanisms, 
wedge brakes and some disc brakes have internal 
mechanisms. 

Several commenters, including Volvo GM 
Heavy Truck, Navistar, GM, Bendix, Rockwell, 
and MVMA, stated that adjustment indicators are 
only practicable with external adjustment designs 
such as S cam brakes with exposed pushrods. 
MVMA stated that there was little if any need to 
require adjustment indicators on internally 
adjusted brakes. Like hydraulic brakes, air-brake 
systems with internal adjustment designs would 
have to be significantly redesigned to incorporate 
an adjustment indicator. Rockwell believed that 
the nominal benefits from having wedge brakes 
and internally adjusted disc brakes equipped with 
indicators did not warrant the significant costs ^ 
that would be needed to redesign these systems. ^ 

Bendix and Lear Siegler explained that some 



PART 571; S121— PRE-234 



external actuators are equipped with a protective 
boot or a scraper seal. 

After reviewing the comments and the available 
information, NHTSA has determined that 
although all air brakes should have a system of 
automatic adjustment, it is not necessary to 
require adjustment indicators on internally 
adjusted brakes. The agency is not aware of any 
significant adjustment problems with internally 
adjusted brakes. In addition, such a requirement 
for these designs would not be practicable given 
the significant feasibility concerns and redesign 
costs to require an adjustment indicator on 
internally adjusted brake systems. The agency 
notes that S cam brakes, except the approximately 
one percent that have protective pushrod boots, 
have exposed air chamber pushrods which easily 
can be marked to indicate brake adjustment. 

S cam brakes whose pushrods are covered 
by protective boots cannot be simply marked, 
since the markings would not be visible to outside 
inspection. The NPRM did not propose to exempt 
booted systems from having to have adjustment 
indicators, describing two designs that have the 
potential to indicate adjustment of such systems. 
In commenting to the docket, Lear Siegler, a 
major air chamber manufacturer, stated that air 
brake actuators equipped with protective boots 
should be exempt from adjustment indication in 
its current technological form. Bendix commented 
that brake actuators with pushrod boots or scraper 
seals should be exempted. 

After a review of the comments to the docket 
and other information on this issue, the agency 
has decided not to require adjustment indicators 
on service brake systems that have pushrod boots. 
Systems having scraper seals and exposed 
pushrods will be required to have adjustment 
indicators, since the pushrods can be easily 
marked and inspected. Brake actuators with 
pushrod boots are made to provide performance 
and reliability under severe operating conditions, 
such as corrosive or hazardous material handling 
and refuse collection and disposal. The heavy- 
duty, durable adjustment indicators, adequately 
integrated into the actuator system, that would be 
necessary to withstand these severe operating 
environments, would cost substantially more than 
indicators on exposed pushrods. Brake systems 
with pushrod boots account for perhaps one per- 
cent of the brake actuator market, as previously 
noted. These systems are being required to have 



automatic brake adjusters. Further, many booted 
systems are used with rolling diaphragm brake 
chambers (roto chambers) that have longer strokes 
than conventional chambers and thus provide a 
greater operating range for automatic slack adjust- 
ers and a longer period of use before the 
underadjustment condition is reached. While the 
agency is not requiring brake systems with booted 
pushrods to have adjustment indicators, it would 
revisit this issue if the number of these systems 
increases substantially in the future. Thus, the 
agency is only requiring externally adjusted 
brakes with exposed pushrods to be equipped 
with adjustment indicators. The agency estimates 
that about 94 percent of air brakes will be 
equipped with indicators. 

3. Miscellaneous Concerns 

Several commenters, including brake indicator 
manufacturers and user groups, requested that the 
agency require air-braked vehicles that are cur- 
rently in use to be retrofitted with automatic 
adjusters and adjustment indicators. NHTSA notes 
that the National Traffic and Motor Vehicle 
Safety Act of 1966 (15 U.S.C. 1381) authorizes 
the agency to promulgate safety standards for new 
vehicles only. The Act does not provide the 
agency with out authority to require the retro- 
fitting of in-use vehicles. Therefore, the agency 
cannot require in-use vehicles to be equipped with 
automatic brake adjusters or adjustment indica- 
tors. 

Flxible commented that it should be allowed 
the option of using manual slack adjusters during 
its certification testing. NHTSA notes that Flxible 
can do whatever it wants in its compliance test- 
ing, if it can establish, should it become necessary 
to do so, that use of its test procedure constitutes 
due care. Nevertheless, NHTSA believes that 
Flxible may have difficulty establishing due care 
if it uses manual adjusters during its certification 
testing, because an earlier rulemaking prohibited 
the disconnecting of automatic adjusters during 
agency compliance testing. (54 FR 40080. 
September 28, 1989). That notice explained that 
an important purpose behind the test conditions 
and procedures is to test vehicles as they will per- 
form when used on the road. Since automatic 
brake adjusters are operational during normal use, 
specifying that they be operational during agency 
compliance testing helps approximate real-world 



PART 571; S121— PRE-235 



conditions and provides a better test of real-world 
performance. 

Advocates for Highway and Auto Safety asked 
whether dollies are required to be equipped with 
automatic adjusters and adjustment indicators 
under the proposals. The requirement for auto- 
matic adjusters and adjustment indicators is 
applicable to dollies since section 571.3 defines a 
"trailer converter dolly" as "a trailer chassis 
equipped with one or more axles, a lower half of 
a fifth wheel and a drawbar." Since trailer chassis 
are trailers and trailers are subject to the require- 
ment, trailer converter dollies also are subject to 
the requirement. 

The ATA requested an exclusion from the 
automatic adjuster requirements for vehicles 
involved in "permit" operations such as 
transporting hazardous waste and explosives. 
While NHTSA has the authority to set standards 
based on vehicle type, it does not typically have 
the authority to set standards based on end use 
(aside from school buses). Even if it had such 
authority, vehicle manufacturers could not predict, 
in many instances, which vehicles were ultimately 
going to be used for permit operations and thus 
could not identify which vehicles were excluded. 
Many vehicles used in permit operations are 
standard trucks and trailers with no special fea- 
tures. If the agency were to attempt to exclude the 
permit operation vehicles by excluding whole 
vehicle types, the exclusion would be overbroad. 
The agency notes that a variety of vehicle types 
are used for these perniit operations, and if 
NHTSA were to exclude all of these types, it 
would be excluding many vehicles not used for 
permit operations. In addition, the professed rea- 
son to exclude vehicles in permit operations (i.e., 
the presumed frequency of manual brake adjust- 
ments) can be accomplished with brakes equipped 
with automatic adjusters. Some truckers involved 
in dangerous activities adjust their brakes every 
day instead of relying on their automatic adjust- 
ers, because automatic adjusters are equipped with 
external adjusting mechanisms similar to the man- 
ual adjusters. Therefore, if a permit hauler desires 
to adjust its brakes manually, it can do so. Based 
on the above, the agency believes that heavy 
haulers involved in permit operations should be 
required to comply with the automatic adjustment 
requirements. 

International Transquip recommended a salt 
spray test and a stroke cycle test for accuracy. 



performance, and readability. NHTSA notes that 
these tests were not proposed in the NPRM and 
does not believe they are necessary at this time. jM 
The agency believes that a safety need for these ~ 
additional requirements could not be established. 
In addition, the existing SAE Recommended Prac- 
tice on automatic adjusters already requires 
environmental chamber tests along with cycle 
testing. If additional information indicated that 
these tests would provide significant safety bene- 
fits at reasonable costs, the agency would con- 
sider proposing them. 

MGM Brakes commented that the SAE Truck 
and Bus Brake Actuator Sub-Committee has writ- 
ten and approved a recommended practice for 
cam or disc brake actuators. However, the SAE 
has withheld this document from publication 
because its policy is to not publish any rec- 
ommended practice that will require another 
manufacturer to infringe a patent. Apparently, one 
air brake actuator manufacturer was recently 
issued a patent on a stroke indicator marking sys- 
tem. Notwithstanding the SAE's concern about 
patent infringement, NHTSA notes that this rule 
specifies a general performance standard. There- 
fore, the agency does not anticipate that restric- ^ 
tions caused by patents will be a problem because ^ 
there are many different indicator designs and air 
chamber pushrods may be marked in many ways. 

Hycliaiilically-Braked Systems 
1 . Brake Adjusters 

The NPRM discussed the need for automatic 
brake adjusters on hydraulically-braked vehicles, 
including passenger cars. The notice explained 
that all new passenger cars have been manufac- 
tured with automatic adjusters for several years. 
The agency stated that such a requirement would 
be consistent with the agency's proposal in Stand- 
ard No. 135 about international brake harmoni- 
zation (52 PR 1474, January 14, 1987. 56 PR 
30528, July 3, 1991). The proposal requested 
comments on whether passenger cars should be 
covered by this amendment to Standard No. 105. 
The proposal also requested comment about 
whether other hydraulically-braked vehicles 
should be required to have automatic brake 
adjusters. 

No commenter expressly supported equipping ^ 
passenger cars and other hydraulic braked ^ 
vehicles with automatic brake adjusters. However, 



PART 571: S121— PRE-236 



several commenters, including General Motors 
and the Motor Vehicle Manufacturers Association 
(MVMA), implicitly supported this requirement 
by commenting that an immediate effective date 
for such vehicles was feasible, provided that the 
requirements did not require the development of 
new designs. Chrysler and Toyota questioned the 
need for such a requirement, claiming that 
hydraulically-braked vehicles are already 
equipped with such devices. 

In addition. Ford and GM commented that, in 
the interests of international brake harmonization, 
the requirements about brake adjusters in Stand- 
ard No. 105 and 135 should be identical. This 
consideration led Ford to state that the proposal 
in Standard No. 105 about automatic correction 
for over-adjustment was not needed. 

After reviewing these comments, NHTSA has 
determined that Standard No. 105 should be 
amended to require automatic brake adjusters. 
Because vehicles subject to Standard No. 105 
typically are equipped with these devices, the 
agency does not anticipate that the requirement 
would pose a burden on manufacturers. In addi- 
tion, amending Standard No. 105 to require these 
devices will result in consistency between that 
Standard and Standard No. 135. The agency notes 
that such consistency is important because under 
the Standard No. 135 proposal, a manufacturer 
could comply with either standard during the five- 
year phase-in period for Standard No. 135. 

2. Adjustment Indicators 

The NPRM stated that even though brake 
adjusters would be required on hydraulically- 
braked vehicles, automatic adjustment indicators 
would not be required on these vehicles. The 
notice explained that the agency believed that 
there were no significant problems with automatic 
brake adjusters for hydraulically-braked vehicles 
or with checking the adjustment of the brakes on 
such vehicles. Nevertheless, the agency requested 
comments about whether adjustment indicators 
should be required on hydraulically-braked 
vehicles. 

Chrysler believed that allowing continued vol- 
untary compliance would be more appropriate 
than mandating installation through rulemaking. 
GM and MVMA stated that indicators should not 
be required on hydraulic brakes because no safety 
need for such a requirement has been dem- 
onstrated. 



NHTSA continues to believe that there is no 
significant safety problem with automatic adjust- 
ers for hydraulically-braked vehicles or with 
checking the adjustment of such vehicles. Accord- 
ingly, the agency has decided not to require 
adjustment indicators on hydraulically-braked 
vehicles. 

Ejfective Date 

The NPRM proposed that the amendments 
become effective two years after promulgation of 
the final rule. The agency proposed the same 
leadtime for both air-braked and hydraulically- 
braked vehicles. 

With respect to automatic brake adjusters on 
air-braked vehicles, the notice explained that most 
truck and bus manufacturers already offer auto- 
matic brake adjusters as standard equipment. The 
agency acknowledged that most truck trailer 
manufacturers do not offer automatic brake 
adjusters as standard equipment; about 30 percent 
of all new trailers are presently ordered with auto- 
matic brake adjusters. In addition, the agency esti- 
mated that about 60 percent of all new medium 
and heavy trucks, buses, and trailers already have 
automatic brake adjusters. NHTSA believed that a 
switch from manual to automatic brake adjusters 
would not require major redesigns of more than 
a few, if any, vehicles because automatic brake 
adjusters are already available for most vehicles 
with manual adjusters and the overall brake sys- 
tem is about the same size, with or without auto- 
matic adjusters. The NPRM further stated that 
manufacturers of automatic brake adjusters could 
easily supply enough adjusters to equip all new 
air-braked tmcks, buses, and trailers within two 
years. 

The NPRM also stated that two years was 
sufficient leadtime for the brake adjustment 
indicator requirement, noting that two major air 
brake manufacturers, with over 75 percent of the 
market, already mark their push rods with a visual 
indicator for under-adjustment. The notice stated 
that other manufacturers should be able to 
develop a brake adjustment indicator within two 
years. The agency requested comments on the 
adequacy of the leadtime generally and specifi- 
cally for any particular types of vehicles or brake 
systems which would require extensive redesign. 
The notice explained that the agency would con- 



PART 571; S121— PRE-237 



sider providing longer leadtime for vehicles or 
brake systems which needed additional leadtime. 

Thirteen commenters addressed the proposed 
leadtime for requiring brake adjusters and adjust- 
ment indicators on air-braked vehicles. The Inter- 
national Brotherhood of Teamsters and a brake 
consultant believed that a leadtime of one year or 
less was appropriate, claiming that the equipment 
is already available. Haldex stated that a one year 
lead time would be possible provided that the 
issue of adjustment indicators was separated. Sev- 
eral commenters, including Ford, the National 
School Transportation Association (NSTA), the 
American Petroleum Institute, the Owner-Operator 
Independent Drivers Association, TTMA, GM, 
and MVMA believed that the proposed two year 
leadtime was appropriate for requirements similar 
to those being adopted in this final rule. Chrysler 
believed that leadtime of three years would be 
necessary for some manufacturers to develop 
automatic adjusters and indicators. 

NHTSA continues to believe that a two year 
leadtime will provide manufacturers adequate 
time to equip air-braked vehicles with brake 
adjusters and adjustment indicators. The agency 
notes that the final rule omits several provisions 
that would have raised significant practicability 
concerns for some vehicle and brake designs. 
NHTSA further notes that although some manu- 
facturers already comply or could quickly bring 
their vehicles into compliance with the require- 
ments, a significant number of small trailer manu- 
facturers would have difficulty complying with 
the amendments unless a two year leadtime is 
provided. 

As for hydraulically-braked vehicles, the notice 
also proposed that the amendment become effec- 
tive two years after publication of the final rule. 
The NPRM requested comment on whether a 
shorter leadtime for hydraulically-braked vehicles 
was appropriate since these vehicles are typically 
produced with automatic brake adjusters. 

GM and MVMA stated that an immediate 
effective date for hydraulically-braked vehicles 
would be acceptable, provided that the amend- 
ments did not require the development of new 
designs. Ford stated that the two year time period 
was more than adequate. No commenter requested 
a leadtime for hydraulically-braked vehicles 
longer than two years. 

Based on the comments and available informa- 
tion, NHTSA has determined that a one year lead- 



time is appropriate for requiring automatic adjust- 
ers on hydraulically-braked vehicles. Those com- 
menters that addressed the issue indicated that an ^m 
immediate effective date would be acceptable. No ™ 
commenter stated that an effective date longer 
than one year was necessary or that a one year 
leadtime would pose an unreasonable burden. 
Based on its review of hydraulically-braked 
vehicles, NHTSA believes that all such passenger 
cars and light trucks are equipped with an auto- 
matic adjuster. As for hydraulically-braked 
medium and heavy duty vehicles, the agency 
notes that these vehicles are typically manufac- 
tured by specialty manufacturers that purchase the 
axle sets and brake components from major 
manufacturers. The agency believes that the major 
manufacturers or trade groups representing the 
specialty manufacturers would have expressed 
their concern if a shorter leadtime had posed a 
hardship. 

This final rule does not have any retroactive 
effect. Under section 103(d) of the National Traf- 
fic and Motor Vehicle Safety Act (15 U.S.C. 
1392(d)), whenever a Federal motor vehicle safety 
standard is in effect, a state may not adopt or 
maintain a safety standard applicable to the same ^ 
aspect of performance which is not identical to 
the Federal standard. Section 105 of the Act (15 
U.S.C. 1394) sets forth a procedure for judicial 
review of final rules establishing, amending or 
revoking Federal motor vehicle safety standards. 
That section does not require submission of a 
petition for reconsideration or other administrative 
proceedings before parties may file suit in court. 

PART 571— [AMENDED] 

In consideration of the foregoing, 49 CFR Part 
571 is amended as follows: 

1. The authority citation for Part 571 continues 
to read as follows: 

Authority: 15 U.S.C. 1392, 1401, 1403, 1407: 
delegation of authority at 49 CFR 1.50. 

§571.105 [Amended] 

2. S5.1 of §571.105 is amended by adding the 
following after the current heading: 

Each vehicle shall be equipped with a service ^ 
brake system acting on all wheels. Wear of the 



PART 571; S121— PRE-238 



service brake shall be compensated for by means 
of a system of automatic adjustment. 



§571.121 [Amended] 

3. S5.1.8 of 571.121 is revised to read as fol- 
lows: 

S5.1.8 Brake distribution and automatic adjust- 
ment. Each vehicle shall be equipped with a serv- 
ice brake system acting on all wheels. 

(a) Brake adjuster. Wear of the service 
brakes shall be compensated for by means of a 
system of automatic adjustment. The readjustment 
limits shall be in accordance with those specified 
in Appendix G to Subchapter B of Chapter III — 
"Minimum Periodic Inspection Standards," 49 
CFR Parts 200 to 399. 

(b) Brake indicator. For each brake equipped 
with an external automatic adjustment mechanism 
and having an exposed pushrod, the condition of 
service brake under-adjustment shall be displayed 
by a brake adjustment indicator that is discernible 
when viewed with 20/40 vision from a location 
adjacent to or underneath the vehicle. 

4. S5.2.2 of §571.121 is revised to read as fol- 
lows: 



S5.2.2 Brake distribution and automatic adjust- 
ment. Each vehicle shall be equipped with a serv- 
ice brake system acting on all wheels. 

(a) Brake Adjuster. Wear of the service 
brakes shall be compensated for by means of a 
system of automatic adjustment. The readjustment 
limits shall be in accordance with those specified 
in Appendix G to Subchapter B of Chapter III — 
■'Minimum Periodic Inspection Standards," 49 
CFR Parts 200 to 399. 

(b) Brake Indicator. For each brake equipped 
with an external automatic adjustment mechanism 
and having an exposed pushrod, the condition of 
service brake under-adjustment shall be displayed 
by a brake adjustment indicator in a manner that 
is discernible when viewed with 20/40 vision 
from a location adjacent to or underneath the 
vehicle. 

Issued on October 14, 1992. 



Marion C. Blakey 
Administrator 



57 F.R. 47793 
October 20, 1992 



PART 571; S121— PRE-239 



MOTOR VEHICLE SAFETY STANDARD NO. 121 

Air Brake Systems — Trucks, Buses and Trailers 

(Docket Nos. 70-16,70-17; Notice No. 2) 



51. Scope. This standard establishes perform- 
ance and equipment requirements for braking sys- 
tems on vehicles equipped with air brake systems. 

52. Purpose. The purpose of this standard is to 
insure safe braking performance under normal and 
emergency conditions. 

53. Application. This standard applies to trucks, 
buses, and trailers equipped with air brake sys- 
tems. However, it does not apply to — 

(a) Any trailer that has a width of more than 
102.36 inches with extendable equipment in the 
fully retracted position and is equipped with two 
short track axles in a line across the width of the 
trailer. 

(b) Any vehicle equipped with an axle that has 
) a GAWR of 29,000 pounds or more; 

(c) Any truck or bus that has a speed attainable 
in 2 miles of not more than 33 mph; 

(d) Any truck that has a speed attainable in 2 
miles of not more than 45 mph, an unloaded 
vehicle weight that is not less than 95 percent of 
its GVWR, and no capacity to carry occupants 
other than the driver and operating crew; 

(e) Any trailer that has a GVWR of more than 
120,000 pounds and whose body conforms to that 
described in the definition of Heavy hauler trailer 
set forth in S4; 

(f) Any trailer that has an unloaded vehicle 
weight which is not less than 95 percent of its 
GVWR; and 

(g) Any load divider dolly. 
Notwithstanding any language to the contrary, 

sections S5.3.1, S5.3.1.1, S5.3.2, S5.3.2.1, 
S5.3.2.2, S5.7.1, S5.7.3(a) and S5.7.3(b) of this 
standard are not applicable to trucks and trailers, 
and section S5.3.1 of this standard is not 
applicable to buses. 

L S4. Definitions. 

Agricultural commodity trailer means a trailer 
that is designed to transport bulk agricultural 



commodities in off-road harvesting sites and to a 
processing plant or storage location, as evidenced 
by skeletal construction that accommodates har- 
vest containers, a maximum length of 28 feet, and 
an arrangement of air control lines and reservoirs 
that minimizes damage in field operations. 

Air brake system means a system that uses air 
as a medium for transmitting pressure or force 
from the driver control to the service brake, but 
does not include a system that uses compressed 
air or vacuum only to assist the driver in applying 
muscular force to hydraulic or mechanical compo- 
nents. 

Antilock system means a portion of a service 
brake system that automatically controls the 
degree of rotational wheel slip at one or more 
road wheels of the vehicle during braking. 

Auto transporter means a truck and a trailer 
designed for use in combination to transport 
motor vehicles, in that the towing vehicle is 
designed to carry cargo at a location other than 
the fifth wheel and to load this cargo only by 
means of the towed vehicle. 

Container chassis trailer means a semitrailer of 
skeleton contruction limited to a bottom frame, 
one or more axles, specially built and fitted with 
locking devices for the transport of intermodal 
shipping containers, so that when the chassis and 
container are assembled, the units serve the same 
function as an over the road trailer. 

Heavy hauler trailer means a trailer with one 
or more of the following characteristics — 

(1) Its brake lines are designed to adapt to 
separation or extension of the vehicle frame; or 

(2) Its body consists only of a platform whose 
primary cargo-carrying surface is not more than 
40 inches above the ground in an unloaded condi- 
tion, except that it may include sides that are 
designed to be easily removable and a permanent 
"front-end structure" as that term is used in 
S393.106of this title. 

Initial brake temperature means the average 
temperature of the service brakes on the hottest 



PART 571; S121-1 



(Rev. 8/15/88) 



axle of the vehicle 0.2 miles before any brake 
application. 

Intermodal shipping container means a 
reusable, transportable enclosure that is expecially 
designed with integral locking devices for secur- 
ing the container to the trailer to facilitate the 
efficient and bulk shipping and transfer of goods 
by, or between various modes of transport, such 
as highway, rail, sea and air. 

Load divider dolly means a composed of a 
trailer chassis and one or more axles, with no 
solid bed, body,or container attached, and which 
is designed exclusively to support a portion of the 
load on a trailer or truck excluded from all the 
requirements of this standard. 

Pulpwood trailer means a trailer that is 
designed exclusively for harvesting logs or pulp- 
wood and constructed with a skeletal frame with 
no means for attachment of a solid bed, body, or 
container, and with an arrangement of air control 
lines and reservoirs designed to minimize damage 
in offroads operations. 

Skid number means the frictional resistance of 
a pavement measured in accordance with Amer- 
ican Society for Testing and Materials Method 
"E-274-70 (as revised July 1974)" at 40 mph, 
omitting water delivery as specified in paragraphs 
S7.1 and 7.2 of that method. 

Straddle trailer means a trailer that is designed 
to transport bulk agricultural commodities from 
the harvesting location as evidenced by a frame- 
work that is driven over the cargo and lifting 
arms that suspend the cargo for transit. 

S5. Requirements. Each vehicle shall meet the 
following requirements under the conditions speci- 
fied in S6. 

S5.1 Required equipment— truclts and buses. 

Each truck and bus shall have the following equip- 
ment: 

S5.1.1 Air Compressor. An air compressor of 
sufficient capacity to increase air pressure in the 
supply and service reservoirs from 85 pounds per 
square inch (p.s.i.) to 100 (p.s.i.) when the engine 
is operating at the vehicle manufacturer's maxi- 
mum recommended rpm within a time, in seconds, 
determined by the quotient — 

actual reservoir capacity x 25 
required reservoir capacity 



[5.1.1.1 Air compressor cut-in pressure. 

Effective October 8, 1992, or at the manufactur- ^ 
er's option effective November 7, 1991, the air ^| 
compressor governor cut-in pressure shall be 
greater than 85 p.s.i. (56 F.R. 50666— October 8. 
1991. Effective: October 8, 1992. Optional compli- 
ance: November 7, 1991.)] 

55.1.2 Reservoirs. One or more service res- 
ervoir systems, from which air is delivered to the 
brake chambers, and either an automatic conden- 
sate drain valve for each service reservoir or a 
supply reservoir between the service reservoir sys- 
tem and the source of air pressure. 

55.1.2.1 The combined volume of all service res- 
ervoirs and supply reservoirs shall be at least 
twelve times the combined volume of all service 
brake chambers at maximum travel of the pistons 
or diaphragms. However, the reservoirs on the 
truck portion of an auto transporter need not meet 
this requirement. 

55.1.2.2 Each reservoir shall be capable of with- 
standing an internal hydrostatic pressure of five M 
times the compressor cutout pressure or 500 p.s.i., ^ 
whichever is greater for 10 minutes. 

55. 1.2.3 Each service reservoir system shall be 
protected against loss of air pressure due to failure 
or leakage in the system between the service res- 
ervoir and the source of air pressure, by check 
valves or equivalent devices whose proper func- 
tioning can be checked without disconnecting any 
air line or fitting. 

55. 1.2.4 Each reservoir shall have condensate 
drain valve that can be manually operated. 

55.1.3 Towing vehicle protection system. If 

the vehicle is intended to tow another vehicle 
equipped with air brakes, a system to protect the 
air pressure in the towing vehicle from the effects 
of a loss of air pressure in the towed vehicle. 

55.1.4 Pressure gauge. A pressure gauge in 
each service brake system, readily visible to a per- 

son seated in the normal driving position, that ^ 
indicates the service reservoir system air pressure. ^ 
The accuracy of the gauge shall be within plus or 



PART 571; S121-2 



minus 7 percent of the compressor cut-out pres- 
sure. 



S5.2 Required equipment-trailers. Each trailer 
shall have the following equipment: 



55.1.5 Warning signal. A signal, other than a 
pressure gauge, that gives a continuous warning to 
a person in the normal driving position when the 
ignition is in the "on" or "run" position and the 
air pressure in the service reservoir system is 
below 60 p.s.i. The signal shall be either visible 
within the driver's forward field of view, or both 
audible and visible. 

55.1.6 Antilock warning signal. A signal on 
each vehicle equipped with an antilock system that 
gives a continuous warning to a person in the nor- 
mal driving position when the ignition is in the 
"on" or "run" position in the event of a total 
electrical failure of the antilock system. The signal 
shall be either visible within the driver's forward 
field of view or both audible, for a duration of at 
least 10 seconds, and continuously visible. The 
signal shall operate in the specified manner each 
time the ignition is returned to the "on" or "run" 
position. 

' S5.1.7 Service brake stop lamp switch. A 

switch that lights the stop lamps when the service 
brake control is statically depressed to a point that 
produces a pressure of 6 p.s.i. or less in the serv- 
ice brake chambers. 

S5.1.8 [Brake distribution and automatic 
adjustment. Each vehicle shall be equipped with 
a service brake system acting on all wheels. 

(a) Brake adjuster. Wear of the service brakes 
shall be compensated for by means of a system 
of automatic adjustment. The readjustment limits 
shall be in accordance with those specified in 
Appendix G to Subchapter B of Chapter III- 
"Minimum Periodic Inspection Standards," 49 
CFR Parts 200 to 399. 

(b) Brake indicator. For each brake equipped 
with an external automatic adjustment mechanism 
and having an exposed pushrod, the condition of 
service brake under-adjustment shall be displayed 
by a brake adjustment indicator that is discernible 
when viewed with 20/40 vision from a location 

y adjacent to or underneath the vehicle. (57 F.R. 
47793— October 20, 1992. Effective: October 20, 
1993.)] 



55.2.1 Reservoirs. One or more reservoirs to 
which the air is delivered from the towing vehicle. 

55.2.1.1 For vehicles manufactured before Octo- 
ber 8, 1992, total service reservoir volume shall be 
at least eight times the combined volume of all 
service brake chambers at maximum travel of the 
pistons or diaphragms. For vehicles manufactured 
on or after October 8, 1992, or at the manufactur- 
er's option for vehicles manufactured on or after 
November 7. 1991, the total volume of each serv- 
ice reservoir shall be at least eight times the com- 
bined volume of all service brake chambers serv- 
iced by that reservoir at the maximum travel of 
the pistons or diaphragms of those service brake 
chambers. However, the reservoirs on a heavy 
hauler trailer and on the trailer portion of an auto 
transporter need not meet the requirements speci- 
fied in S5.2.1.1. 

55.2.1.2 Each reservoir shall be capable of with- 
standing an internal hydrostatic pressure of 500 
p.s.i. for 10 minutes. 

55.2.1.3 Each reservoir shall have a condensate 
drain valve that can be manually operated. 

55.2.1.4 Each service reservoir shall be protected 
against loss of air pressure due to failure or leak- 
age in the system between the service reservoir 
and its source of air pressure by check valves or 
equivalent devices. 

55.2.1.5 For vehicles manufactured before Octo- 
ber 8, 1992, a reservoir shall be provided that is 
capable, when pressurized to 90 p.s.i., of releasing 
the vehicle's parking brakes at least once and that 
is unaffected by a loss of air pressure in the serv- 
ice brake system. This requirement need not be 
met if the vehicle meets the applicable require- 
ments specified in S5. 1.1.1, the second sentence of 
S5.2.1.1, and S5.8.1 through S5.8.4, notwithstand- 
ing the effective date of those requirements. 

55.2.2 [Brake distribution and automatic 
adjustment. Each vehicle shall be equipped with 
a service brake system acting on all wheels. 



PART 571: S121-3 



(Rev. 10/20/92) 



(a) Brake adjuster. Wear of the service brakes 
shall be compensated for by means of a system 
of automatic adjustment. The readjustment limits 
shall be in accordance with those specified in 
Appendix G to Subchapter B of Chapter III- 
" Minimum Periodic Inspection Standards," 49 
CFR Parts 200 to 399. 

(b) Brake indicator. For each brake equipped 
with an external automatic adjustment mechanism 
and having an exposed pushrod, the condition of 
service brake under-adjustment shall be displayed 
by a brake adjustment indicator in a manner that 
is descemible when viewed with 20/40 vision 
from a location adjacent to or underneath the 
vehicle. (57 F.R. 47793— October 20, 1992. Effec- 
tive: October 20, 1993.)] 

S5.3 Service brakes— road tests. The service 
brake system on each truck and bus shall, under 
the conditions of S6.1, meet the requirements of 
S5.3.1, S5.3.3, and S5.3.4 when tested without 
adjustments other than those specified in this 
standard. The service brake system on each trailer 
shall, under the conditions of S6.1, meet the 
requirements of S5.3.2, S5.3.3, and S5.3.4 when 
tested without adjustments other than those speci- 
fied in this standard. However, a heavy hauler 
trailer and the truck and trailer portions of an auto 
transporter need not meet the requirements of 
S5.3. 

S5.3.1 Stopping distance — trucks and buses. 

When stopped six times for each combination of 
weight, speed, and road condition specified in 
S5.3.1.1, in the sequence specified in Table I, the 
vehicle shall stop at least once in not more than 
the distance specified in Table II, measured from 
the point at which movement of the service brake 
control begins, without any part of the vehicle 
leaving the roadway and without lockup of any 
wheel at speeds above 10 mph except for — 

(a) Controlled lockup of wheels allowed by an 
antilock system; or 

(b) Lockup of wheels on nonsteerable axles 
other than the two rearmost nonliftable, 
nonsteerable axles on a vehicle with more than 
two nonsteerable axis. 



Table I. — Stopping Sequence 

1. Burnish. 

2. Control trailer service brake stops at 60 mph ^| 
(for truck-tractors tested with a control trailer in 
accordance with S6. 1.10.6). 

3. Control trailer emergency brake stops at 60 
mph (for truck-tractors tested with a control 
trailer in accordance with S6. 1.10.7). 

4. Stops with vehicle at gross vehicle weight 
rating — 

(a) 20 mph service brake stops on skid number 
of 81. 

(b) 60 mph service brake stops on skid number 
of 81. 

(c) 20 mph service brake stops on skid number 
of 30. 

(d) 20 mph emergency brake stops on skid 
number of 8 1 . 

(e) 60 mph emergency brake stops on skid 
number of 8 1 . 

5. Parking brake test with vehicle loaded to gross 
vehicle weight rating. 

6. Stops with vehicle at unloaded weight plus 500 
lb.— 

(a) 20 mph service brake stops on skid number ^ 
of81. 4 

(b) 60 mph service brake stops on skid number 
range 81. 

(c) 20 mph service brake stops on skid number 
range 30. 

(d) 20 mph emergency brake stops on skid 
number range 8 1 . 

(e) 60 mph emergency brake stops on skid 
number range 8 1 . 

7. Parking brake test with vehicle at unloaded 
weight plus 500 lb. 

S5.3.1.1 Stop the vehicle from 60 mph and 20 
mph on a surface with a skid number of 81, and 
from 20 mph on a wet surface with a skid number 
of 30, with the vehicle (a) loaded to its gross 
vehicle weight rating, and (b) at its unloaded 
vehicle weight plus 500 pounds (including driver 
and instrumentation). If the speed attainable in 2 
miles is less than 60 mph, the vehicle shall stop 
from a speed in Table II that is 4 to 8 mph less 
than the speed attainable in 2 miles. 



(Rev. 10/20/92) 



PART 571: S121-4 



Table II. — Stopping Distance in Feet 







Service Brake stopping distance 


Emergency 


Brake 


stopping 


distance 


Vehicle speed in miles per 


Column 


I Skid No. 81 Column 2 Skid No. 30 




Skid No. 


81 




hour 
















Column 3 








Column 4 


20 




35 60 


83 








85 


25 




53 


123 








131 


30 




75 


170 








186 


35 




101 


225 








250 


40 




131 










325 


45 




165 


358 








409 


50 




203 


435 








504 


55 




246 


520 








608 


60 




293 


613 








720 



55.3.2 Stopping capability — trailers. When 
tested at each combination of weight, speed, and 
road condition specified in S5.3.2.1, in the 
sequence specified in Table I, with air pressure of 
90 p.s.i. in the control line and service reservoir 
system and with no application of the towing 
vehicle's brakes, a trailer shall stop without any 
part of the trailer leaving the roadway and without 
lockup of any wheel at speeds above 10 mph, 
except for — 

(a) Controlled lockup of wheels allowed by an 
antilock system; or 

(b) Lockup of wheels on nonsteerable axles 
other than the two reannost nonliftable; 
nonsteerable axles on a trailer with more than two 
nonsteerable axles; or 

(c) In the case of an axle system having more 
than four wheels, lockup of any wheel other than 
the outermost wheel at each end of the axle sys- 
tem. 

55.3.2.1 Stop the vehicle from 60 mph and 20 
mph on a surface with skid number of 81, and 
from 20 mph on a wet surface with a skid number 
30, with the vehicle (a) loaded to its gross vehicle 
weight rating, and (b) at its unloaded vehicle 
weight plus 500 pounds (including instrumenta- 
tion). 

55.3.2.2 When stopped in accordance with S5.3.2, 
a pulpwood trailer need not meet the requirements 
relating to wheel lockup, but must nevertheless 
meet the requirements of staying within the 12- 
foot lane. 

55.3.3 Brake actuation time. Each service brake 
system shall meet the requirements of S5.3.3.1, 
except that, at the option of the manufacturer, 
vehicles manufactured before May 3, 1991 may 



meet the requirements specified in either S5.3.3.2 
or S5.3.3.3 

55.3.3.1 (a) With an initial service reservoir sys- 
tem air pressure of 100 p.s.i., the air pressure in 
each brake chamber shall, when measured from 
the first movement of the service brake control, 
reach 60 p.s.i. in not more than 0.45 seconds in 
the case of trucks and buses, 0.50 seconds in the 
case of trailers, other than trailer converter dollies, 
designed to tow another vehicle equipped with air 
brakes, 0.55 seconds in the case of trailer con- 
verter dollies, and 0.60 seconds in the case of 
trailers other than trailers designed to tow another 
vehicle equipped with air brakes shall meet the 
above actuation time requirement with a 50-cubic- 
inch test reservoir connected to the control line 
output coupling. A trailer, including a trailer con- 
verter dolly, shall meet the above actuation time 
requirement with its control line input coupling 
connected to the test rig shown in Figure 1 . 

(b) For a vehicle that is manufactured after 
May 3, 1991 and is designed to tow another 
vehicle equipped with air brakes, the pressure in 
the 50-cubic-inch test reservoir referred to in 
S5.3.3.1(a) shall, when measured from the first 
movement of the service brake control, reach 60 
p.s.i. not later than the time the fastest brake 
chamber on the vehicle reaches 60 p.s.i. or, at the 
option of the manufacturer, in not more than 0.35 
seconds in the case of trucks and buses, 0.55 sec- 
onds in the case of trailer converter dollies, and 
0.50 seconds in the case of trailers other than 
trailer converter dollies. 

55.3.3.2 Optional requirement for vehicles 
manufactured before May 3, 1991. With an ini- 
tial service reservoir system air pressure of 100 
p.s.i., the air pressure in each brake chamber shall, 
when measured from the first movement of the 



PART 571; SI 21-5 



service brake control, reach 60 p.s.i. in not more 
tiian 0.45 seconds in the case of trucks and buses, 
and 0.60 seconds in the case of trailers. A vehicle 
designed to tow another vehicle equipped with air 
brakes shall meet the above actuation time 
requirement with a 50-cubic-inch test reservoir 
connected to the control line output coupling. A 
trailer, including a trailer converter dolly, shall 
meet the above actuation time requirement with its 
control line input coupling connected to the test 
rig shown in Figure 1. 

S5.3.3.3 Optional requirement for vehicles 
manufactured before May 3, 1991. With an ini- 
tial service reservoir system air pressure of 100 
p.s.i., the air pressure in each brake chamber shall, 
when measured from the first movement of the 
service brake control, reach 60 p.s.i. in not more 
than 0.45 seconds in the case of trucks and buses, 
0.35 seconds in the case of trailer converter dol- 
lies, and 0.30 seconds in the case of trailers other 
than trailer converter dollies. A vehicle designed 
to tow another vehicle equipped with air brakes 
shall meet the above actuation-time requirement 
with a 50-cubic-inch test reservoir connected to 
the control line output coupling. A trailer, includ- 
ing a trailer converter dolly, shall meet the above 
actuation time requirement with its control line 
input coupling connected to the test rig shown in 
Figure 1(a). 

S5.3.4 Brake release time. Each service brake 
system shall meet the requirements of S5.3.4.1, 
except that, at the option of the manufacturer, 
vehicles manufactured before May 3, 1991 may 
meet the requirements specified in either S5. 3.4.2 
or S5.3.4.3. 

S5.3.4.1 (a) With an initial sei-vice brake chamber 
air pressure of 95 p.s.i., the air pressure in each 
brake chamber shall, when measured from the first 
movement of the service brake control, fall to 5 
p.s.i. in not more than 0.55 seconds in the case of 
trucks and buses, and fall to 5 p.s.i. in not more 
than 0.55 seconds in the case of trucks and buses, 
1.00 seconds in the case of trailers, other than 
trailer converter dollies, designed to tow another 
vehicle equipped with air brakes, 1.10 seconds in 
the case of the trailer converter dollies, and 1.20 
seconds in the case of trailers other the trailers 
designed to tow another vehicle equipped with air 
brakes. A vehicle designed to tow another vehicle 
equipped with air brakes shall be capable of meet- 



ing the above release time requirement with a 50- 
cubic-inch test reservoir connected to the control 
line coupling. A trailer, including a trailer con- ^ 
verter dolly, shall meet the above release time 
requirements with its brake system connected to 
the test rig shown in Figure 1 . 

(b) For vehicles designed to tow another 
vehicle equipped with air brakes, effective May 3, 
1991, the pressure in the 50-cubic-inch test res- 
ervoir referred to in S5.3.4.1(a) shall, when meas- 
ured from the first movement of the service brake 
control, fall to 5 p.s.i. in not more than 0.75 sec- 
onds in the case of trucks and buses, 1.10 seconds 
in the case of trailer converter dollies, and 1.00 
seconds in the case of trailers other than trailer 
converter dollies. 

[S5.3.4.2 Optional requirement for vehicles 
manufactured before May 3, 1991. With an ini- 
tial service brake chamber air pressure of 95 p.s.i., 
the air pressure in each brake chamber shall, when 
measured from the first movement of the service 
brake control, fall to 5 p.s.i. in not more than 0.55 
seconds in the case of trucks and buses, and 1.20 
seconds in the case of trailers. A vehicle designed 
to tow another vehicle equipped with air brakes m 
shall meet the above release time requirement with 
a 50-cubic-inch test reservoir connected to the 
control line output coupling. A trailer, including a 
trailer converter dolly, shall meet the above 
release time requirement with its control line input 
coupling connected to the test rig shown in Fig- 
ure 1. 

[S5.3.4.3 Optional requirement for vehicles 
manufactured before May 3, 1991. With an ini- 
tial service brake chamber air pressure of 95 p.s.i., 
the air pressure in each brake chamber shall, when 
measured from the first movement of the service 
brake control, fall to 5 p.s.i. in not more than 0.55 
seconds in the case of trucks and buses, and 0.65 
seconds in the case of trailers. A vehicle designed 
to tow another vehicle equipped with air brakes 
shall meet the above release time requirement with 
a 50-cubic-inch test reservoir connected to the 
control line output coupling. A trailer, including a 
trailer converter dolly, shall meet the above 
release time requirement with its control line input 
coupling connected to the test rig shown in Figure d 

1(a). (54 F.R. 18890— May 3, 1989. Effective: June 
2, 1989.)] 



PART 571; S121-6 



[S5.3.5 Control signal pressure differential- 
converter dollies and trailers designed to tow 
another vehicle equipped with air brakes. 

(a) For a trailer manufactured on or after 
August 23, 1993 and designed to tow another 
vehicle equipped with air brakes, the pressure dif- 
ferential between the control line input coupling 
and a 50 cubic inch test reservoir attached to the 
control line output coupling shall not exceed the 
values specified in S5. 3. 5(a)(1) through (4) — 

(1) 1 p.s.i. at all input pressures equal to or 
greater than 5 p.s.i., but not greater than 20 p.s.i.; 
and 

(2) 2 p.s.i. at all input pressures greater than 
20 p.s.i. 

(b) The requirements in S5.3.5(a) shall be 
met — 

(1) When the pressure at the imput coupling 
is steady, increasing or decreasing; 

(2) When air is applied to or released from 
the control line input coupling using the trailer 
test rig shown in Figure 1; 

(3) With a fixed orifice consisting of a 
0.0180 inch diameter hole (no. 77 drill bit) in a 
0.032 inch thick disc installed in the control line 
between the trailer test rig coupling and the 
vehicle's control line input coupling; and 

(4) Operating the trailer test rig in the same 
manner and under the same conditions as it is 
operated during testing to measure brake actuation 
and release times, as specified in S5.3.3 and 
S5.3.4, except for the installation of the orifice in 
the control line to restrict airflow rate. (57 F.R. 
37902— August 21, 1992. Effective: August 23, 
1992.) Vehicles manufactured before the effective 
date may comply with the rule's amendments. 
Effective September 21, 1992.] 

S5.4 Service brake system — dynamometer 
tests. When tested without prior road testing, 
under the conditions of S6.2, each brake assembly 
shall meet the requirements of S5.4.1, S5.4.2, and 
S5.4.3 when tested in sequence and without 
adjustments other than those specified in the 
standard. For purposes of the requirements of 
S5.4.2 and S5.4.3, an average deceleration rate is 
the change in velocity divided by the deceleration 
time measured from the onset of deceleration. 
However, a brake assembly on a heavy hauler 
trailer manufactured before July 1, 1979, need not 
meet the requirements of this section. 



S5.4.1 Brake retardation force. The sum of the 

retardation forces exerted by the brakes on each 
vehicle designed to be towed by another vehicle 
equipped with air brakes shall be such that the 
quotient — 

sum of the brake retardation forces 



sum of GAWRs 

relative to brake chamber air pressure shall have 
values not less than those shown in Column 1 of 
Table III. Retardation force shall be determined as 
follows — 

Table III. — Brake Retardation Force 

BRAKE RETARDATION BRAKE CHAMBER PRES- 

FORCE GAWR Column 1 SURE, p.s.i. Column 2 



0.05 
0.12 
0.18 
0.25 
0.31 
0.37 
0.41 



S5.4.1.1 After burnishing the brake pursuant to 
S6.2.6, retain the brake assembly on the inertia 
dynamometer. With an initial brake temperature 
between 125°F and 200°F, conduct a stop from 50 
mph, maintaining brake chamber air pressure at a 
constant 20 p.s.i. Measure the average torque 
exerted by the brake from the time the specified 
air pressure is reached until the brake stops and 
divide by the static loaded tire radius specified by 
the tire manufacturer to determine the retardation 
force. 

Repeat the procedure six times, increasing the 
brake chamber air pressure by 10. After each 
stop, rotate the brake drum or disc until the 
temperature of the brake falls to between 125°F 
and 200°F. 

S5.4.2 Brake power. When mounted on an iner- 
tia dynamometer, each brake shall be capable of 
making 10 consecutive decelerations at an average 
rate of 9 fpsps from 50 mph to 15 mph, at equal 
intervals of 72 seconds, and shall be capable of 
decelerating to a stop from 20 mph at an average 
deceleration rate of 14 fpsps one minute after the 
10th acceleration. The series of decelerations shall 
be conducted as follows — 

S5.4.2.1 With an initial brake temperature 
between 150°F and 200°F for the first brake 
application, and the drum or disc rotating at a 



PART 571; S121-7 



speed equivalent to 50 mph, apply the brake and 
decelerate at an average deceleration rate of 9 
fpsps to 15 mph. Upon reaching 15 mph, acceler- 
ate to 50 mph and apply the brake for a second 
time 72 seconds after the start of the first applica- 
tion. Repeat the cycle until 10 decelerations have 
been made. The service line air pressure shall not 
exceed 100 p.s.i. during any deceleration. 

S5.4.2.2 One minute after the end of the last 
deceleration required by S5.4.2.1 and with the 
drum or disc rotating at a speed of 20 mph, decel- 
erate to a stop at an average deceleration rate of 
14 fpsps. 

S5.4.3 Brake recovery. Starting 2 minutes after 
completing the tests required by S5.4.2, the brake 
of a vehicle other than either front axle brake of 
a truck-tractor shall be capable of making 20 
consecutive stops from 30 mph at an average 
deceleration rate of 12 fpsps, at equal intervals of 
1 minute measured from the start of each brake 
application. The service line air pressure needed to 
attain a rate of 12 fpsps shall be not more than 85 
Ib./in.-, and not less than 20 Ib./in.- for a brake 
not subject to the control of an antilock system, or 
12 Ib./in.- for a brake subject to the control of an 
antilock system. 

S5.5 Antilock system. 



meets the requirements of S5.6.1 or S5.6.2, at the 
manufacturer's option, and the requirements of 
S5.6.3 and S5.6.4. S5.6.5, and S5.6.6. However, 
the trailer portion of any agricultural commodity 
trailer, heavy-hauler trailer, or pulpwood trailer 
shall meet the requirements of this section or, at 
the option of the manufacturer, the requirements 
of § 393.43 of this title. 

S5.6.1 Static retardation force. With all other 
brakes rendered inoperative, during a static draw- 
bar pull in a forward or rearward direction, the 
static retardation force produced by the application 
of the parking brakes shall be — 

(a) In the case of a vehicle other than a truck- 
tractor that is equipped with more than two axles, 
such that the quotient — 

static retardation force 



GVWR 

is not less than 0.28 for any axle other than a 
steerable front axle; and 

(b) In the case of a truck-tractor that is 
equipped with more than two axles, such that the 
quotient — 

static retardation force 



GVWR 



is not less than 0.14. 



55.5.1 Antilock system failure. On a vehicle 
equipped with an antilock system, electrical failure 
of any part of the antilock system shall not 
increase the actuation and release times of the 
service brakes. 

55.5.2 Antilock system power — trailers. [On a 

trailer (including a trailer converter dolly) 
equipped with an antilock system that requires 
electrical power for operation, the power shall be 
obtained from either the stop lamp circuit or one 
or more separate electrical circuit or circuits 
specifically provided to power the trailer antilock 
system. The antilock system shall automatically 
receive power from the stop lamp circuit, if the 
separate power circuit or circuits are not in use. 
(57 F.R. 30911— July 13, 1992. Effective: August 12, 
1992.)] 

S5.6 Parking brake system. Each vehicle other 
than a trailer converter dolly shall have a parking 
brake system that under the conditions of S6.1 



55.6.2 Grade holding. With all parking brakes 
applied, the vehicle shall remain stationary facing 
uphill and facing downhill on a smooth, dry port- 
land cement concrete roadway with a 20% grade, 
both (a) when loaded to its gross vehicle weight 
rating, and (b) at its unloaded vehicle weight plus 
500 pounds (including driver and instrumentation). 

55.6.3 Application and holding. Each parking 
brake system shall meet the requirements of 
S5.6.3.1 through S5.6.3.4, except that, at the 
option of the manufacturer, the parking brake sys- 
tem in each vehicle manufactured before Decem- 
ber 9, 1991, may meet either those requirements 
specified in S5.6.3.5. 

S5.6.3.1 The parking brake system shall be 
capable of achieving the minimum performance 
specified either in S5.6.1 or S5.6.2 with any single 
leakage-type failure, in any other brake system, of 
a part designed to contain compressed air or brake 
fluid (except failure of a component of a brake 



(Rev. 7/13/92) 



PART 571; S121-8 



chamber housing, [but including failure of any 
brake chamber diaphragm that is part of any other 
\ brake system including a diaphragm which is 
common to the parking brake system and any 
other brake system), when the pressures in the 
vehicle's parking brake chambers are at the levels 
determined in S5.6.3.4. (56 F.R. 26927— June 12, 
1991. Effective: December 9, 1991.)] 

55.6.3.2 [A mechanical means shall be provided 
that, after a parking brake application is made 
with the pressures in the vehicle's parking brake 
chambers at the levels determined in S5.6.3.4, and 
all air and fluid pressures in the vehicle's braking 
systems are then bled down to zero, and without 
using electrical power, holds the parking brake 
application with sufficient parking retardation 
force to meet the minimum performance specified 
in S5.6.3.1 and in either S5.6.1 or S5.6.2. (56 F.R. 
26927— June 12, 1991. Effective: December 9, 
1991.)] 

55.6.3.3 [For trucks and buses, with an initial res- 
ervoir system pressure of 100 p.s.i. and, if 
designed to tow a vehicle equipped with air 
brakes, with a 50-cubic-inch test reservoir con- 

y nected to the supply line coupling, no later than 
three seconds from the time of actuation of the 
parking brake control, the mechanical means 
referred to in S5.6.3.2 shall be actuated. For trail- 
ers, with the supply line initially pressurized to 
100 p.s.i. using the supply line portion of the 
trailer test rig (Figure 1) and, if designed to tow 
a vehicle equipped with air brakes, with a 50- 
cubic-inch test reservoir connected to the rear sup- 
ply line coupling, no later than three seconds from 
the time venting to the atmosphere of the front 
supply line coupling is initiated, the mechanical 
means referred to in S5.6.3.2 shall be acUiated. 
This requirement shall be met for trucks, buses 
and trailers both with and without any single leak- 
age-type failure, in any other brake system, of a 
part designed to contain compressed air or brake 
fluid (excluding failure of a component of a brake 
chamber housing but including failure of any 
brake chamber diaphragm that is part of any other 
brake system including a diaphragm which is 
common to the parking brake system and any 
other brake system). (56 F.R. 26927— June 12, 
1991. Effective: December 9, 1991.)] 

55.6.3.4 [The parking brake chamber pressures 
for S5.6.3.1 and S5.6.3.2 are determined as fol- 



lows. For trucks and buses, with an initial res- 
ervoir system pressure of 100 p.s.i. and, if 
designed to tow a vehicle equipped with air 
brakes, with a 50-cubic-inch test reservoir con- 
nected to the supply line coupling, any single 
leakage-type failure, in any other brake system, of 
a part designed to contain compressed air of brake 
fluid (excluding failure of a component of a brake 
chamber housing but including failure of any 
brake chamber diaphragm that is part of any other 
brake system including a diaphragm which is 
common to the parking brake system and any 
other brake system), is introduced in the brake 
system. The parking brake control is actuated and 
the pressures in the vehicle's parking brake cham- 
bers are measured three seconds after that actu- 
ation is initiated. For trailers, with the supply line 
initially pressurized to 100 p.s.i. using the supply 
line portion of the trailer test rig (Figure 1) and, 
if designed to tow a vehicle equipped with air 
brakes, with a 50-cubic-inch test reservoir con- 
nected to the rear supply line coupling, any single 
leakage-type failure, in any other brake system, of 
a part designed to contain compressed air or brake 
fluid (excluding failure of a component of a brake 
chamber housing but including failure of any 
brake chamber diaphragm that is part of any other 
brake system including a diaphragm which is 
common to the parking brake system and any 
other brake system), is introduced in the brake 
system. The front supply line coupling is vented 
to the atmosphere and the pressures in the 
vehicle's parking brake chambers are measured 
three seconds after that venting is initiated. (56 
F.R. 26927— June 12, 1991. Effective: December 9, 
1991.)] 

S5.6.3.5. Optional requirement for vehicles 
manufactured before [December 9, 1991]. The 

parking brake system shall be capable of achiev- 
ing the minimum performance specified either in 
S5.6.1 or S5.6.2. with any single leakage-type fail- 
ure, in any other brake system, of a part designed 
to contain compressed air or brake fluid (except 
failure of a component of a brake chamber hous- 
ing [but including failure of any brake chamber 
diaphragm that is part of any other brake system 
including a diaphragm which is common to the 
parking brake system and any other brake sys- 
tem).] Once applied, the parking brakes shall be 
held in the applied position solely by mechanical 
means. (56 F.R. 26927— June 12, 1991. Effective: 
December 9, 1991.) 



PART 571: S121-9 



(Rev. 6/12/91) 



S5.6.4 — Parking brake control — trucks and 
buses. The parking brake control shall be sepa- 
rate from the service brake control. It shall be 
operable by a person seated in the normal driving 
position. The control shall be identified in a man- 
ner that specifies the method of control operation. 
The parking brake control shall control the park- 
ing brakes of the vehicle and of any air braked 
vehicle that it is designed to tow. 

[S5.6.5 Release performance. Effective 
December 9, 1991, each parking brake system 
shall meet the requirements specified in S5.6.5.1 
through S5.6.5.4. 

[S5.6.5.1 For trucks and buses, with initial condi- 
tions as specified in S5.6.5.1, at all times after an 
application actuation of the parking brake control, 
and with any subsequent level of pressure, or 
combination of levels of pressure, in the reservoirs 
of any of the vehicle's brake systems, no reduc- 
tion in parking brake retardation force shall result 
from a release actuation of the parking brake con- 
trol unless the parking brakes are capable, after 
such release, of being reapplied at a level meeting 
the minimum performance specified either in 
S5.6.1 or S5.6.2. This requirement shall be met 
both with and without the engine on, and with and 
without any single leakage-type failure, in any 
other brake system, of a part designed to contain 
compressed air or brake fluid (excluding failure of 
a component of a brake chamber housing but 
including failure of any brake chamber diaphragm 
that is part of any other brake system including a 
diaphragm which is common to the parking brake 
system and any other brake system). 

[S5.6.5.2 The initial conditions for S5.6.5.1 are as 
follows. The reservoir system pressure is 100 p.s.i. 
If the vehicle is designed to tow a vehicle 
equipped with air brakes, a 50-cubic-inch test res- 
ervoir is connected to the supply line coupling. 

[S5.6.5.3 For trailers, with initial conditions as 
specified in S5. 6.5.4, at all times after actuation of 
the parking brakes by venting the front supply line 
coupling to the atmosphere, and with any subse- 
quent level of pressure, or combination of levels 
of pressure, in the reservoirs of any of the 
vehicle's brake systems, the parking brakes shall 
not be releasable by repressurizing the supply line 
using the supply line portion of the trailer test rig 
(Figure 1) to any pressure above 70 p.s.i., unless 



the parking brakes are capable, after such release, 
of reapplication by subsequent venting of the front 
supply line coupling to the atmosphere, at a level ^ 
meeting the minimum performance specified ^ 
either in S5.6.1 or S5.6.2. This requirement shall 
be met both with and without any single leakage- 
type failure, in any other brake system, of a part 
designed to contain compressed air or brake fluid 
(excluding failure of a component of a brake 
chamber housing but including failure of any 
brake chamber diaphragm that is part of any other 
brake system including a diaphragm which is 
common to the parking brake system and any 
other brake system). 

[S5.6.5.4 The initial conditions for S5.6.5.3 are as 
follows. The reservoir system and supply line are 
pressurized to 100 p.s.i., using the supply line por- 
tion of the trailer test rig (Figure 1 ). If the vehicle 
is designed to tow a vehicle equipped with air 
brakes, a 50-cubic-inch test reservoir is connected 
to the rear supply line coupling. (56 F.R. 26927 — 
June 12, 1991. Effective: December 9, 1991.)] 

[S5.6.6 Accumulation of actuation energy. 

Effective December 9, 1991, each parking brake 
system shall meet the requirements specified in M 
S5.6.6.1 through S5.6.6.6. ^ 

[S5.6.6.1 For trucks and buses, with initial condi- 
tions as specified in S5.6.6.2, the parking brake 
system shall be capable of meeting the minimum 
performance specified either in S5.6. 1 or S5.6.2, 
with any single leakage-type failure, in any other 
brake system, of a part designed to contain com- 
pressed air or brake fluid (excluding failure of a 
component of a brake chamber housing but 
including failure of any brake chamber diaphragm 
that is part of any other brake system including a 
diaphragm which is common to the parking brake 
system and any other brake system), at the conclu- 
sion of the test sequence specified in S5.6.6.3. 

[S5.6.6.2 The initial conditions for S5.6.6.1 are as 
follows. The engine is on. The reservoir system 
pressure is 100 p.s.i. If the vehicle is designed to 
tow a vehicle equipped with air brakes, a 50- 
cubic-inch test reservoir is connected to the supply 
line coupling. 

[S5.6.6.3 The test sequence for S5.6.6.1 is as fol- J 
lows. The engine is turned off. Any single leakage " 
type failure, in any other brake system, of a part 



(Rev. 6/12/91) 



PART 571; S121-10 



designed to contain compressed air or brake fluid 
(excluding failure of a component of a brake 
\ chamber housing but including failure of any 
brake chamber diaphragm that is part of any other 
brake system including a diaphragm which is 
common to the parking brake system and any 
other brake system), is then introduced in the 
brake system. An application actuation of the 
parking brake control is then made. Thirty seconds 
after such actuation, a release actuation of the 
parking brake control is made. Thirty seconds 
after the release actuation, a final application actu- 
ation of the parking brake control is made. 

[S5.6.6.4 For trailers, with initial conditions as 
specified in S5. 6.6.5, the parking brake system 
shall be capable of meeting the minimum perform- 
ance specified either in S5.6.1 or S5.6.2, with any 
single leakage-type failure, in any other brake sys- 
tem, of a part designed to contain compressed air 
or brake fluid (excluding failure of any brake 
chamber diaphragm that is part of any other brake 
system including a diaphragm which is common 
to the parking brake system and any other brake 
system), at the conclusion of the test sequence 
specified in S5.6.6.6. 

[S5.6.6.5 The initial conditions for S5. 6.6.4 are as 
follows. The reservoir system and supply line are 
pressurized to 100 p.s.i., using the supply line por- 
tion of the trailer test rig (Figure 1). If the vehicle 
is designed to tow a vehicle equipped with air 
brakes, a 50-cubic-inch test reservoir is connected 
to the rear supply line coupling. 

[S5.6.6.6 The test sequence for S5. 6.6.4 is as fol- 
lows. Any single leakage type failure, in any other 
brake system, of a part designed to contain com- 
pressed air or brake fluid (excluding failure of a 
component of a brake chamber housing but 
including failure of any brake chamber diaphragm 
that is part of any other brake system including a 
diaphragm which is common to the parking sys- 
tem and any other brake system), is introduced in 
the brake system. The front supply line coupling 
is vented to the atmosphere. Thirty seconds after 
the initiation of such venting, the supply line is 
repressurized with the trailer test rig (Figure 1). 
Thirty seconds after the initiation of such 
repressurizing of the supply line, the front supply 
line is vented to the atmosphere. This procedure is 
conducted either by connection and disconnection 
of the supply line coupling or by use of a valve 



installed in the supply line portion of the trailer 
test rig near the supply line coupling. (56 F.R. 
26927— June 12, 1991. Effective: December 9, 
1991.)] 

S5.7 Emergency brake system— trucks and 
buses. Each vehicle shall be equipped with an 
emergency brake system which, under the condi- 
tions of S6. 1, conforms to the requirements of 
S5.7.1 through S5.7.3. However, the truck portion 
of an auto transporter need not meet the road test 
requirements of S5.7.1 and S5.7.3. 

55.7.1 Emergency brake system performance. 

When stopped six times for each combination of 
weight and speed specified in S5.3.1.1 on a road 
surface with a skid number of 81, with a single 
failure in the service brake system of a part 
designed to contain compressed air or brake fluid 
(except failure of a common valve, manifold brake 
fluid housing, or brake chamber housing), the 
vehicle shall stop at least once in not more than 
the distance specified in Column 3 of Table II, 
measured from the point at which movement of 
the service brake control begins, without any part 
of the vehicle leaving the roadway, except that a 
truck-tractor tested at its unloaded vehicle weight 
plus 500 pounds shall stop at least once in not 
more than the distance specified in Column 4 of 
Table II. 

55.7.2 Emergency brake system operation. 

The emergency brake system shall be applied and 
released, and be capable of modulation, by means 
of the service brake control. 

55.7.3 Towing vehicle emergency brake 
requirements. In addition to meeting the other 
requirements of S5.7, a vehicle designed to tow 
another vehicle equipped with air brakes shall — 

(a) In the case of a truck-tractor in the 
unloaded condition and a single unit truck which 
is capable of towing an air-brake equipped 
vehicle and is loaded to gross vehicle weight rat- 
ing, be capable of meeting the requirements of 
S5.7.1 by operation of the service brake control 
only, with the trailer air supply line and air con- 
trol line from the towing vehicle vented to the 
atmosphere in accordance with S6.1.14; 

(b) In the case of a truck-tractor loaded to gross 
vehicle weight rating, be capable of meeting 
S5.7.1 by operation of the service brake control 
only, with the aid control line from the towing 



PART 571; S121 



(Rev. 6/12/91) 



vehicle vented to the atmosphere in accordance 
with S6. 1.14; and 

(c) Be capable of modulating the air in the sup- 
ply or control line to the trailer by means of the 
service brake control with a single failure in the 
towing vehicle service brake system as specified 
inS5.7.1. 

[S5.8 Trailer pneumatic system failure 
performance. Each trailer shall meet the require- 
ments of S5.8.1 through S5.8.3. (56 F.R. 50666— 
October 8, 1991. Effective: October 8, 1992. 
Optional compliance: November 7, 1991.)] 

[S5.8.1 Emergency braking capability. Each 
trailer other than a trailer converter dolly shall 
have a parking brake system that conforms to S5.6 
and that applies with the force specified in S5.6.1 
or S5.6.2 when the air pressure in the supply line 
is at atmospheric pressure. A trailer converter 
dolly shall have, at the manufacturer's option — 

(a) A parking brake system that confonns to 
S5.6 and that applies with the force specified in 
S5.6.1 or S5.6.2 when the air pressure in the sup- 
ply line is at atmospheric pressure; or 

(b) An emergency system that automatically 
applies the service brakes when the service res- 
ervoir is at any pressure above 20 Ib./in.- and the 
supply line is at atmospheric pressure. However, 
any agricultural commodity trailer, heavy hauler 
trailer, or pulpwood trailer shall meet the require- 
ments of S5.5.1 or, at the option of the manufac- 
turer, the requirements of §393.43 of this title. 
(56 F.R. 50666— October 8, 1991. Effective: Octo- 
ber 8, 1992. Optional compliance: November 7, 
1991.)] 

[S5.8.2 Supply line pressure retention. Effec- 
tive October 8, 1992, or at the manufacturer's 
option effective November 7, 1991, any single 
leakage type failure in the service brake system 
(except for a failure of the supply line, a valve 
directly connected to the supply line or a compo- 
nent of a brake chamber housing) shall not result 
in the pressure in the supply line falling below 70 
p.s.i., measured at the forward trailer supply cou- 
pling. A trailer shall meet the above supply line 
pressure retention requirement with its brake sys- 
tem connected to the trailer test rig shown in Fig- 
ure 1 , with the reservoirs of the trailer and test rig 
initially pressurized to 100 p.s.i., and the regulator 
of the trailer test rig set at 100 p.s.i. 



[S5.8.3 Automatic application of parking 
brakes. Effective October 8, 1992, or at the 
manufacturer's option effective November 7, ^ 
1991, with an initial reservoir system pressure of " 
100 p.s.i. and initial supply line pressure of 100 
p.s.i., and if designed to tow a vehicle equipped 
with air brakes, with a 50-cubic-inch test reservoir 
connected to the rear supply line coupling, and 
with any subsequent single leakage type failure in 
any other brake system, of a part designed to con- 
tain compressed air or brake fluid (excluding fail- 
ure of a component of a brake chamber housing 
but including failure of any diaphragm of a brake 
chamber which is common to the parking brake 
system and any other brake system), the parking 
brakes shall not provide any brake retardation as 
a result of complete or partial automatic applica- 
tion of the parking brakes. (56 F.R. 50666— Octo- 
ber 8, 1991. Effective: October 8, 1992. Optional 
compliance: November 7, 1991.)] 

S6. Conditions. The requirements of S5 shall 
be met by a vehicle when it is tested according to 
the conditions set forth below, without replacing 
any brake system part or making any adjustments 
to the brake system except as specified. Unless 
otherwise specified, where a range of conditions is A 
specified, the vehicle must be capable of meeting 
the requirements at all points within the range. On 
vehicles equipped with automatic brake adjusters, 
the automatic brake adjusters must remain acti- 
vated at all times. Compliance of vehicles manu- 
factured in two or more stages may, at the option 
of the final-stage manufacturer, be demonstrated 
to comply with this standard by adherence to the 
instructions of the incomplete vehicle manufac- 
turer provided with the vehicle in accordance with 
S568.4(a)(7)(ii) and § 568.5 of title 49 of the Code 
of Federal Regulations. 

S6.1 Road test condition. 

S6.1.1 Except as otherwise specified, the vehicle 
is loaded to its gross vehicle weight rating, distrib- 
uted proportionally to its gross axle weight rat- 
ings. During the burnish procedure specified in 
S6.1.8, truck tractors shall be loaded to their 
GVWR, by coupling them to an unbraked flatbed 
semitrailer, which semitrailer shall be loaded so 
that the weight of the tractor-trailer combination ^ 
equals the GVMR of the tmck tractor. The load ^ 
on the unbraked flatbed semitrailer shall be 



(Rev. 10/8/91) 



PART 571: S121-12 



located so that truck tractor's wheels do not lock 
during burnish. 

56.1 .2 The inflation pressure is as specified by the 
vehicle manufacturer for the gross vehicle weight 
rating. 

56.1.3 Unless otherwise specified, the trans- 
mission selector control is in neutral or the clutch 
is disengaged during all decelerations and during 
static parking brake tests. 

56.1.4 All vehicle openings (doors, windows, 
hood, trunk, cargo doors, etc.) are in a closed 
position except as required for instrumentation 
purposes. 

56.1.5 The ambient temperature is between 32°F 
and 100°F. 

56.1 .6 The wind velocity is zero. 

56.1.7 Unless otherwise specified, stopping tests 
are conducted on a 12-foot wide, level, straight 
roadway having a skid number of 81, inclusive, 
chosen at the option of the manufacturer. The 
vehicle is aligned in the center of the roadway at 
the beginning of the stop. 

56.1.8 The brakes are burnished before testing in 
accordance with S6. 1.8.1. However, for vehicles 
with parking brake systems not utilizing the serv- 
ice brake friction elements, burnish the friction 
elements of such systems prior to the parking 
brake test according to the manufacturer's rec- 
ommendations. 

S6. 1.8.1 [Vehicles manufactured before Septem- 
ber 1, 1993 may be burnished according to the 
procedures set forth in S6. 1.8. 1(a) or S6. 1.8. 1(b) 
of this section, at the manufacturers option. 
Vehicles manufactured on or after September 1, 
1993 shall be burnished according to the proce- 
dures set forth in S6. 1.8. 1(b) of this section. 

Table IV. 



1 175 40 to 20 mph. 

2 25 45 10 20 mph. 

3 25 50 to 20 mph. 

4 25 55 to 20 mph. 

5 250 60 to 20 mph. 

(a) With the transmission in the highest gear 

appropriate for the series given in Table IV, make 



500 brake applications at a deceleration rate of 10 
fpsps, or at the vehicle's maximum deceleration 
rate, if not less than 10 fpsps, in the sequence 
specified. Except where an adjustment is speci- 
fied, after each brake application accelerate 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 attain any speed 
specified in 1 mile, continue to accelerate until 
the specified speed is reached or until the vehicle 
has traveled 1.5 miles from the initial point of the 
previous brake application, whichever occurs first. 
If during any of the brake applications specified 
in Table IV the hottest brake reaches 550°F, make 
the remainder of the 500 brake applications from 
that snub condition, except that a higher or lower 
snub condition shall be used as necessary to 
maintain an after-stop temperature of 500°F ± 
50°F. However, if at a snub condition of 40 to 20 
mph, the temperature of the hottest brake exceeds 
550°F, make the remainder of the 500 brake 
applications from that snub condition, without 
regard to brake temperature. The brakes shall be 
adjusted three times during the burnish procedure, 
after 125, 250, and 375 snubs and after complet- 
ing this burnish, with each adjustment made in 
accordance with the manufacturer's recommenda- 
tions. Any automatic pressure limiting valve is in 
use to limit pressure as designed, except that any 
automatic front axle pressure limiting valve is 
bypassed if the temperature of the hottest brake 
on a rear axle exceeds the temperature of the hot- 
test brake on a front axle by more than 125°F. A 
bypassed valve is reconnected if the temperature 
of the hottest brake on a front axle exceeds the 
temperature of the hottest brake on a rear axle by 
100°F or more. 

(b) With the transmission in the highest gear 
appropriate for a speed of 40 mph, make 500 
snubs between 40 mph and 20 mph at a decelera- 
tion rate of 10 fpsps, or at the vehicle's maximum 
deceleration rate if less than 10 fpsps. Except 
where an adjustment is specified, after each brake 
application accelerate to 40 mph and maintain 
that speed until making the next brake application 
at a point 1 mile from the initial point of the pre- 
vious brake application. If the vehicle cannot 
attain a speed of 40 mph in 1 mile, continue to 
accelerate until the vehicle reaches 40 mph or 
until the vehicle has traveled 1.5 miles from the 
initial point of the previous brake application. 



PART 571; S121-13 



whichever occurs first. Any automatic pressure 
limiting valve is in use to limit pressure as 
designed. The brakes shall be adjusted three times 
during the burnish procedure, in accordance with 
the manufacturer's recommendations, after 125, 
250, and 375 snubs, and shall be adjusted after 
burnish in accordance with the manufacturer's 
recommendations.] (53 F.R. 8190— March 14, 
1988. Effective: September 11, 1988.) 

56.1.9 Static parking brake tests for a semi-trailer 
are conducted with the front end supported by an 
unbraked dolly. The weight of the dolly is 
included as part of the trailer load. 

56.1.10 In a test other than a static parking brake 
test, a truck-tractor is tested at its gross vehicle 
weight rating by coupling it to a flatbed 
semitrailer (hereafter, control trailer) as specified 
inS6.1.10.1 toS6.1.10.7. 

56.1.10.1 The control trailer conforms to this 
standard. 

56.1.10.2 The center of gravity of the loaded con- 
trol trailer is on the trailer's longitudinal centerline 
at a height of 66 ±3 in. above the ground. 

56.1.10.3 For a truck-tractor with a rear axle gross 
axle weight rating of 26,000 lb. or less, the control 
trailer has a single axle with a gross axle weight 
rating of 18,000 lb. and a length, measured from 
the transverse centerline of the axle to the center- 
line of the kingpin, of 258 ± 6 in. 

56.1.10.4 For a truck-tractor with a total rear axle 
gross axle weight rating of more than 26,000 lb 
the control trailer has a tandem axle with a com- 
bined gross axle weight rating of 32,000 lb and a 
length, measured from the transverse centerline 
between the axles to the centerline of the kingpin, 
of 390 ±6 in. 

56.1.10.5 The control trailer is loaded so that its 
axle is loaded to its gross axle weight rating and 
the tractor is loaded to its gross vehicle weight rat- 
ing, with the tractor's fifth wheel adjusted so that 
the load on each axle measured at the tire-ground 
interface is most nearly proportional to the axles' 
respective gross axle weight ratings. 

56.1.10.6 Test equipment specification. The 

control trailer's service brakes are capable of stop- 



ping the combination from the maximum speed at 
which the tractor is tested, under the conditions of 
S6. 1 , without assistance from the tractor brakes, in 
the distance found by multiplying the value 68, 
90, 115, 143, 174, 208, or 245 (corresponding to 
a speed of 30, 35, 40, 45, 50, 55, or 60 mph as 
appropriate for the truck-tractor tested) by the 
ratio — 

weight on all axles of combination 



weight on trailer axles 

with the tractor's fifth wheel adjusted as specified 
in S6. 1.10.5, the trailer service reservoirs pressur- 
ized to 100 lb./in.2, and the trailer loaded so that 
its axle is at gross axle weight rating and its king- 
pin is at empty vehicle weight. The stopping dis- 
tance is measured from the point at which move- 
ment of the valve controlling the trailer brakes 
begins. The service brake chambers on the trailer 
reach 60 Ib./in.- in not less than 0.20 second and 
not more than 0.30 second, measured from the 
instant at which movement of the valve control- 
ling the trailer brakes begins. 

S6.1.10.7 Test equipment specification. The 

control trailer's emergency brakes are capable of A 
stopping the combination under the conditions of 
S6. 1 from the maximum speed at which the tractor 
is tested, without assistance from the tractor's 
brakes, in the distance found by multiplying the 
emergency brake stopping distance in column 3 of 
Table II by the ratio — 

weight on all axles of combination 
weight on trailer axles 

with the combination loaded in accordance with 
S6. 1.10.5. Stopping distance is measured from the 
point at which movement of the valve controlling 
the trailer brakes begins. In the case of control 
trailers that utilize parking brakes for emergency 
stopping capability, the pressure in the trailer's 
spring parking brake chambers falls from 95 lb./ 
in.- to 5 Ib./in.- in not less than 0.50 second and 
not more than 0.60 second, measured from the 
instant at which movement of the valve control- 
ling the trailer's spring parking brakes begins. 

S6.1.11 Special drive conditions. A vehicle 
equipped with an interiocking axle system of a 
front wheel drive system that is engaged and dis- ^ 
engaged by the driver is tested with the system \ 

disengaged. 



PART 571; S121-14 



56.1.12 Liftable axes. A vehicle with a hftable 
axle is tested at gross vehicle weight rating with 

\ the liftable axle down and at unloaded vehicle 
weight with the liftable axle up. 

56.1.13 [Trailer test rig. The trailer test rig 
shown in Figure 1 is calibrated in accordance with 
the calibration curves shown in Figure 3. For the 
requirements of S5.3.3.1 and S5.3.4.1, the pressure 
in the trailer test rig reservoir is initially set at 100 
p.s.i. for actuation tests and 95 p.s.i. for release 
tests. 

(b) The trailer test rig shown in Figure 1(a) is 
capable of increasing the pressure in a 50 cubic 
inch reservoir from atmospheric to 60 Ib./in.- in 
0.06 second, measured from the first movement 
of the service brake control to apply service brake 
pressure and of releasing pressure in such a res- 
ervoir from 95 to 5 Ib./in.^ in 0.22 second meas- 
ured from the first movement of the service brake 
control to release service brake pressure. (54 F.R. 
18890— May 3, 1989. Effective: June 2, 1989.)] 

56.1.14 In testing the emergency braking system 
of towing vehicles under S5.7.3(a) and S5.7.3(b) 
the hose(s) is vented to the atmosphere at any time 
not less than 1 second and not more than 1 minute 
before the emergency stop begins, while the 
vehicle is moving at the speed from which the 
stop is to be made and any manual control for the 
towing vehicle protection system is in the position 
to supply air and brake control signals to the 
vehicle being towed. No brake application is made 
from the time the line(s) is vented until the emer- 
gency stop begins and no manual operation of the 
parking brake system or towing vehicle protection 
system occurs from the time the line(s) is vented 
until the stop is completed. 

S6.2 Dynamometer test conditions. 

S6.2.1 The dynamometer inertia for each wheel is 
equivalent to the load on the wheel with the axle 
loaded to its gross axle weight rating. For a 
vehicle having additional gross axle weight ratings 
specified for operation at reduced speeds, the 
GAWR used is that specified for a speed of 50 



mph, or, at the option of the manufacturer, any 
speed greater than 50 mph. 

56.2.2 The ambient temperature is between 75°F 
and 100°F. 

56.2.3 Air at ambient temperature is directed uni- 
formly and continuously over the brake drum or 
disc at a velocity of 2,200 feet per minute. 

56.2.4 The temperature of each brake is measured 
by a single plus type thermocouple installed in the 
center of the lining surface of the most heavily 
loaded shoe or pad as shown in Figure 2. The 
thermocouple is outside any center groove. 

56.2.5 The rate of brake drum or disc rotation on 
a dynamometer corresponding to the rate of rota- 
tion on a vehicle at a given speed is calculated by 
assuming a tire radius equal to the static loaded 
radius specified by the tire manufacturer. 

56.2.6 Brakes are burnished before testing as fol- 
lows: Place the brake assembly on an inertia 
dynamometer and adjust the brake as rec- 
ommended by the brake manufacturer. Make 200 
stops from 40 mph at a deceleration of 10 fpsps, 
with an initial brake termpeature on each stop of 
not less than 315°F and not more than 385°F. 
Make 200 additional stops from 40 mph at a 
deceleration of 10 fpsps with an initial brake 
temperamre on each stop of not less than 450°F 
and not more than 550°F. The brakes shall be 
adjusted three times during the burnish procedure, 
after 100, 200, and 300 stops, and at the conclu- 
sion of the burnishing, in accordance with the 
manufacturer's recommendations. 

56.2.7 The brake temperature is increased to a 
specified level by conducting one or more stops 
from 40 mph at a deceleration of 10 fps. The 
brake temperature is decreased to a specified level 
by rotating the drum or disc at a constant 30 mph. 

36 F.R. 3817 
February 27, 1971 



PART 571; S121-15 



(Rev. 5/3/89) 



Va" L.D. Line 



0^€>r 



1000 in3 
Reser- 
voir 



Control 
Valve 



© 



(mvJ — QRV HIMrj 



\ 



30' - W L.D. Line 
(Straight or Coiled) 



Shop 
Air 



© 

I 30' - ^/6" 



■ Control Line 
Glad Hand 



I.D. Line (Straight or Coiled) 



L 



Supply Line 
Glad Hand 



SV —Shut-off Valve 

R — Regulator (set at 1 00 psi for actuation tests and 95 

psi for release test) 
CV —Check Valve 

MV — Metering Valve (Variable or Fixed) 
QRV— Quick Release Valve 

Figure 1 .—Trailer Test Rig. 
(56 F.R. 50666— October 8, 1991.)] 



TRACTOR PROTECTION VALVE 

(OPTIONAL) 




SERVICE BRAKE PEDAL 



Figure la.— Trailer Test Rig 
PART 571; 8121— Art Page 1 



(Rev. 5/3/89) 



PART 571; S121-16 



0.295 DIA MAX- 




CO DRILL NO. 31 
0.100 MAX DEPTH 
BEFORE GRIND 



GRIND TO 1/8- 
MAX BEFORE 
PLACING IN LINING 




Figure 2. — Thermocouple Installation 



PART 571; S121-17 



100 -i 



40 



20 — 



Initial Valve Movement & Release 



(Pressure vs Time for 
50 in3 Test Reservoir) 



\ 



X 



A 



^ 



^ 



Apply 



60 psi 
0.35 sec 



/- Initial Valve Movement & Apply 



Release 




95-5 psi 0.7 sec 



0.1 0.2 0.3 0.4 0.5 0.6 

Time (Sec.) fromlnitial Valve Movement 
Figure 3.— Calibration Curves 
PART 571 : SI 21— Art Page 2 



0.7 



(Rev. 5/3/89) 



PART 571: S121-18 



PREAMBLE TO AN AMENDMENT TO FEDERAL MOTOR VEHICLE SAFETY 

STANDARD NO. 131 

School Bus Pedestrian Safety Devices 

(Docket No. 90-01 ; Notice 3) 
RIN 2127-AE33 



ACTION: Final rule; response to petition for 
reconsideration. 

SUMMARY: This rule amends certain provisions 
in Standard No. 131, School Bus Pedestrian Safety 
Devices (49 CFR 571.131) which requires new 
school buses to be equipped with a stop signal 
arm. Specifically, the amendment requires the stop 
signal arm to be aligned relative to the lower edge 
of the passenger window. In addition, with respect 
to stop arms equipped with lights to meet the 
standard's conspicuity requirement, this notice 
amends the flash rate so that it more closely cor- 
relates to the most recent recommended practice 
of the Society of Automotive Engineers. These 
amendments will increase the effectiveness of stop 
signal arms by improving their visibility to other 
motorists. 

EFFECTIVE DATE: The amendment becomes 
effective September 2, 1992. 

SUPPLEMENTARY INFORMATION: 

L Background 

On May 3, 1991, NHTSA published a final 
rule establishing a new Federal motor vehicle 
safety standard requiring new school buses to be 
equipped with a stop signal arm. (56 FR 20363). 
A stop signal arm is a device patterned after 
conventional "STOP" signs and attached to the 
left side of a school bus. When the school bus 
stops, the stop signal ami autoinatically extends 
outward from the bus. Its purpose is to alert 
motorists that a school bus is stopping or has 
stopped. The standard specifies requirements 
about the stop signal arm's appearance, size, con- 
spicuity, operation and location. 

The agency established this new safety standard 
after reviewing the available information, includ- 
ing the docket comments, the Fatal Accident 
Reporting System (FARS) data, and a report 



issued by the National Academy of Sciences enti- 
tled "Improving School Bus Safety," (Special 
Report No. 222). The agency determined that a 
safety need exists for better controlling the move- 
ment of vehicles passing stopped school buses 
during the loading and unloading of passengers. 

n. Petitions For Reconsideration 

NHTSA received two petitions for reconsider- 
ation of the stop signal arm rule, one was a peti- 
tion from the California Department of Education 
(DOE) requesting a change in the requirement 
regarding the height at which a stop signal arm 
should be located. DoE asked that the reference 
to the lower edge of the driver's window frame 
in SS.4.1(b) be deleted, stating that some school 
bus models are designed so that the lower edge 
of the driver's side window is lower than the side 
windows at the passenger seats. The petitioner 
believed that installation of the stop signal arm 
relative to the lower edge of the driver's window 
could reduce the visibility of the stop signal arm 
to other motorists and thus reduce the arm's 
effectiveness. The California DOE recommended 
that the reference in S5.4.1(b) be changed to the 
lower edge of the passenger windows. 

The other petition was from Epicor Industries, 
a manufacturer of turn siqnals, hazard warnings 
and alternating flashers. It requested that the 
agency change the requirements for the flash rate 
for stop signal arm lights under S6.2.2 to conform 
with the most recent version of SAE J 1054, 
"Warning Lamp Flashers, (October 1989). The 
petitioner stated that such an amendment would 
assure that the two lamps would flash alternately 
and have "on"times that meet an accepted stand- 
ard and have been proven effective. The previous 
version of SAE J 1054 (January 1977), which was 
used by NHTSA to develop the final requirements 
of S6.2.2, was determined by the SAE to be 
incorrectly written. Epicor also requested that 
Standard No. 131 be amended to include a provi- 



PART 131— PRE- 13 



sion requiring all replacement parts for stop signal 
arms to comply with the requirements of the 
standard similar to the provisions of S5.7 in 
Standard No. 108, Lamps, Reflective ment. 
Devices, and Associated 

III. Agency's Review of The Petitions For 
Reconsideration 

2. Reference Plane for Stop Signal Arm's Loca- 
tion 

In the final rule, NHTSA specified location 
requirements applicable to the stop signal arm, 
based on the goal of standardization, the views of 
State school transportation personnel about effec- 
tive locations for stop signal arms, typical loca- 
tion of these devices, and the Vehicle Safety 
Act's directive that the safety standards be objec- 
tive. Section SS currently specifies that school 
buses be equipped with at least one stop signal 
arm installed on the left side of the bus so that, 
when extended, (1) it is perpendicular to the side 
of the bus, plus or minus five degrees, (2) it has 
the top edge of the octagon parallel to and within 
6 inches of a horizontal plane passing through the 
lower edge of the driver's window frame, and (3) 
its vertical centerline is at least 9 inches away 
from the school bus body. The agency stated that 
these requirements will provide uniform location 
specifications while providing users flexibility to 
install stop signal arms consistent with their 
experiences with these devices. The location 
requirements are also intended to ensure that the 
stop signal arms are visible to motorists trailing 
and approaching stopped school buses. 

As mentioned above, California DoE requested 
that S5.4.1(b) be amended so that the reference 
plane passes through the lower edge of the pas- 
sengers' windows instead of the lower edge of the 
driver's window. The petitioner believed that this 
change was necessary to accommodate the new 
practice of designing some school buses so that 
the driver's window is lower than the passengers" 
windows. 

NHTSA notes that the aqency's decision in the 
final rule to specify the lower edge of the driver's 
window was based on the assumption that the 
lower edge of the driver's window and pas- 
sengers' windows were all in the same horizontal 
plane. While this assumption remains valid in 
most situations, the agency is aware that an 
increasinq number of new school buses are being 
designed so that the driver's side window is lower 



than the passenger side windows. The agency 
believes that new school buses are being designed 
in this manner to improve school bus driver visi- 
bility of student pedestrians in front of and along • 
side of the school bus. 

NHTSA has decided to amend the requirements 
of S5.4.1(b) to require that the top edge of the 
stop signal arm be aligned with the lower edge of 
the frame of the passenger window immediately 
behind the driver's window. The agency believes 
that specifying this window as the reference will 
ensure that stop signal arms are more visible to 
other motorists, since some school buses are 
designed with the bottom of the driver's window 
being well below that of the passengers' win- 
dows. Under the May 1991 final rule, as the 
lower edge of the driver's window gets closer to 
the ground, so does the signal stop arm, thereby 
reducing its visibility to other motorists, and thus 
its effectiveness. 

The agency anticipates that this amendment 
will not result in any adverse impact to school 
bus manufacturers or users that were planning to 
install the stop signal arm relative to the lower 
edge of the driver's window. In most buses, the 
driver's window is on the same plane as the pas- 
sengers' windows. In addition, the agency has • 
reviewed those new bus designs with lower driver 
windows and believes that installing the stop sig- 
nal arm relative to the lower edge of the pas- 
sengers' windows will not result in any additional 
compliance problems for manufacturers. 

B. Flash Rate 

In the final rule, the agency determined that a 
stop signal arm must either be reflectorized or 
have flashing lamps to provide increased con- 
spicuity, or both. The final rule stated that if 
flashing lamps are used, they must comply with 
the requirements for color, flash rate, and vibra- 
tion, moisture, dust, corrosion, photometry, and 
warpage, as set forth in S6.2. The notice stated 
that the tests for flash rate were patterned after 
the tests in the Society of Automotive Engineer's 
(SAE's) Recommended Practice, J 1054, Warning 
Lamp Alternating Flashers (January 1977). 
Specifically, S6.2.2 of the final rule states: 

The lamps on each side of the stop signal arm, 
when operated at the manufacturer's design 
load, shall flash at a rate of 60-120 flashes per ^ 
minute with a current "on" time of 50 percent. 



PART 131— PRE- 14 



The petition from Epicor requested that the 
^ requirements for the flash rate be patterned after 
^ the more recent SAE Recommended Practice for 
ahemating flashers promulgated in October 1989. 
The October 1989 Recommended Practice cleared 
up technical problems caused by the existence of 
two SAE Recommended Practices dealing with 
alternating flashing lamps — SAE J 1054 and SAE 
J 1104. While J 1054 described the performance 
parameters for a flasher, J 1104 specified how to 
assure that a particular flasher design conformed 
to the performance parameters. In October 1989, 
SAE revised J 1054 to incorporate the pertinent 
features and allowable elements of both SAE 
Recommended Practices, thus eliminating the 
need for J 1104. In doing so. SAE substituted the 
flash rate conditions of J 1104 for those in J 1054. 
After reviewing the modified SAE rec- 
ommended practice, NHTSA has decided to pat- 
tern S6.2.2 after the October 1989 SAE Rec- 
ommended Practice, J 1054. Given that the SAE 
has determined that the January 1977 version of 
J 1054 is technically incorrect, the agency believes 
that S6.2.2 should be revised to reflect the lan- 
guage adopted in the October 1989 version of 
^ J 1054. 

C. Replacement Equipment 

The final rule specified that Standard No. 131 
is a vehicle standard that applies to new school 
buses. The Standard does not apply to stop signal 
arms sold in the aftermarket. Nor do the Stand- 
ard's provisions apply to stop signal ami replace- 
ment parts. 

Epicor requested that Standard No. 131 be 
amended to include a section requiring that all 
replacement bulbs and lenses for stop signal arms 
meet the requirements of the standard. It was sug- 
gested that such an amendment would parallel 
S5.7 of Standard No. 108, which requires replace- 
ment lights to comply with that standard. 
Requesting that Standard No. 131 be amended to 
make the replacement bulbs and lenses subject to 
the requirements of the standard is based on the 
assumption that such a requirement is necessary 
for safety. Specifically, the petitioner stated that 
the amendment would ensure that the standard is 
"not abused over time as worn parts and compo- 
nents are replaced.'" 
% In determining whether to extend Standard No. 

131 's requirements to aftermarket replacement 
parts, the agency contacted Specialty Manufactur- 



ing Company, the largest manufacturer of stop 
signal arms. Specialty Manufacturing explained 
that the bulbs installed in the flashing lamps are 
the same bulbs used in passenger car stop lamps. 
In addition, the replacements are normally bought 
directly from Specialty Manufacturing because the 
lamp lens has a unique shape and hole pattern. 

NHTSA has decided not to extend Standard 
No. 131 to replacement parts. The agency dis- 
agrees with the petitioner's contention that 
inferior replacement parts will be used unless the 
Standard is amended. The agency notes that the 
only replacement bulbs available can be assumed 
to be in compliance with the standard's require- 
ments for stop signal arm bulbs since those bulbs 
are the same as the bulbs required to comply with 
the requirements for passenger car replacement 
lamps under S5.7 of Standard No. 108. The only 
known source of replacement lamp lens is the 
original manufacturer, and the agency does not 
anticipate the entry of low quality replacement 
bulbs and lamps into the market given the low 
cost and low volume of this market. Accordingly, 
the agency has decided to deny the petitioner's 
request to establish performance requirements for 
replacement equipment. 

NHTSA has determined that an immediate 
effective date is in the public interest. The amend- 
ments made by this notice impose no new 
requirements but instead either increase manufac- 
turer flexibility or are for purposes of clarification 
or correction. Since the new Standard No. 131 is 
effective September 1, 1992, the agency has 
determined that it is in the public interest to have 
these amendments become effective at the same 
time. Absent these amendments, manufacturers 
availing themselves to this flexibility would be 
unable to certify that their school buses comply 
with Standard No. 131. 

This final rule does not have any retroactive 
effect. Under section 103(d) of the National Traf- 
fic and Motor Vehicle Safety Act (15 U.S.C. 
1392(d)), whenever a Federal motor vehicle safety 
standard is in effect, a state may not adopt or 
maintain a safety standard applicable to the same 
aspect of performance which is not identical to 
the Federal standard. Section 105 of the Act (15 
U.S.C. 1394) sets forth a procedure for judicial 
review of final rules establishing, amending or 
revoking Federal motor vehicle safety standards. 
That section does not require submission of a 



PART 131— PRE- 15 



petition or reconsideration or other administrative 
proceedings before parties may file suit in court. 
In consideration of tfie foregoing, 49 CFR Part 
571 is amended as follows: 

1. The authority citation for Part 571 of Title 
49 continues to read as follows: 

PART 571— [AMENDED] 

Authorit}^: 15 U.S.C 1392, 1401, 1403, 1407; 
delegation of authority at 49 CFR 1 .50. 

2. In Section 571.131, the title of the section to 
read as follows: 

§571.131 Standard No. 131; School bus pedes- 
trian devices. 

3. In Standard No. 131, S5.4 is revised to read 
as follows: 



S5.4 The stop signal arm shall be installed on the 
left side of the bus. 

S5.4.1 The stop signal arm shall be located such 
that, when in the extended position: 

(a) The stop signal arm is perpendicular to the 
side of the bus, plus or minus five degrees; 



(b) The top edge of the stop signal arm is par- 
allel to and not more than 6 inches from a hori- 
zontal plane tangent to the lower edge of the 
frame of the passenger window immediately 
behind the driver's window; and 

(c) The vertical centerline of the stop signal 
arm is not less than 9 inches away from the side 
of the school bus. 

S5.4.2 A second stop signal arm may be installed 
on a school bus. That stop signal arm shall comply 
with S5.4andS5.4.1. 



4. In Standard No. 131, S6.2.2 is revised to 
read as follows: 

S6.2.2 Flash Rate. The lamps on each side of 
the stop signal arm, when operated at the manu- 
facturer's design load, shall flash at a rate of 60 
to 120 flashes per minute with a current "on" 
time of 30 to 75 percent. The total of the percent 
current "on" time for the two terminals shall be 
between 90 and 110 . 

Issued on August 28, 1992. 



STOP 



I- 



stroke width of letters 
20 mm (079 inch) 



im (0.47 inch) 

Figure 1 . Characteristics of Stop Signal Device 



Marion C. Blakey 
Administrator, Acting 

57 F.R. 40131 
September 2, 1992 



PART 131— PRE- 16 



MOTOR VEHICLE SAFETY STANDARD NO. 
School But Pedestrian Safety Devices 



131 



51. Scope. This standard establishes require- 
ments for devices that can be installed on school 
buses to improve the safety of pedestrians in the 
vicinity of stopped school buses. 

52. Purpose. The purpose of this standard is to 
reduce deaths and injuries by minimizing the like- 
lihood of vehicles passing a stopped school bus 
and striking pedestrians in the vicinity of the bus. 

53. Application. This standard applies to school 
buses. 

54. Definitions. 

Stop signal arm means a device that can be 
extended outward from the side of a school bus 
to provide a signal to other motorists not to pass 
the bus because it has stopped to load or dis- 
charge passengers. 

55. Requirements. Each school bus shall be 
equipped with a stop signal arm meeting the 
requirements of S5.1 through S5.5 as depicted in 
Figure 1. 



STOP 




I 150 mm ( 



Figure 1. Cliarateristics of Stop Signal Device 



55.2 The stop signal arm shall be red on both 
sides, except as provided in S5.2.1 and S5.2.2, and 
S5.2.3. 

55.2.1 The stop signal arm shall have a white 
border at least 12 mm (0.47 inches) wide on both 
sides, except as provided in S5.2.3. 

55.2.2 The stop signal arm shall have the word 
"STOP" displayed in white upper-case letters on 
both sides, except as provided in S5.2.3. The let- 
ters shall be at least 150 mm (5.9 inches ) in 
height and have a stroke width of at least 20 mm 
(0.79 inches). 

55.2.3 When two stop signal arms are installed 
on a school bus, the rear-most stop signal arm 
shall not contain any lettering, symbols, or mark- 
ings on the forward side. 

55.3 Conspicuity. The stop signal arm shall 
comply with either S5.3.1 or S5.3.2, or both. 

55.3.1 The entire surface of both sides of the 
stop signal arm shall be reflectorized with type III 
retroreflectorized material that meets the minimum 
specific intensity requirements of S6. 1 and Table 
1. When two stop signal arms are installed on a 
school bus, the forward side of the rearmost stop 
signal arm shall not be reflectorized. 

55.3.2 Each side of the stop signal arm shall 
have at least two red lamps that meet the require- 
ments of S6.2. The lamps shall be centered on the 
vertical centerline of the stop arm. one of the 
lamps shall be located at the extreme top of the 
stop arm and the other at its extreme bottom. 

55.4 The stop signal arm shall be installed on the 
left side of the bus. 



S5.1 The stop signal arm shall be a regular octa- 
gon which is at least 450 mm x 450 mm (17.72 
inches x 17.72 inches) in diameter. 



S5.4.1 The stop signal arm shall be located such 
that, when in the extended position: 

(a) The stop signal arm is perpendicular to the 
side of the bus, plus or minus five degrees; 



PART 131-1 



(b) [The top edge of the stop signal aim is par- 
allel to and not more than 6 inches from a hori- 
zontal plane tangent to the lower edge of the 
frame of the passenger window immediately 
behind the driver's window; and 

(c) The vertical centerline of the stop signal 
arm is not less than 9 inches away from the side 
of the school bus. (57 F.R. 40131— September 2, 
1992. Effective: September 2, 1992)] 

S5.4.2 A second stop signal arm may be installed 
on a school bus. That stop signal arm shall comply 
withS5.4andS5.4.1. 

S5.5 The stop signal arm shall be automatically 
extended in such a manner that it complies with 
S5.4.1, at a minimum whenever the red signal 
lamps required by S5.1.4 of Standard No. 108 are 
activated; except that a device may be installed 
that prevents the automatic extension of a stop sig- 
nal arm. The mechanism for activating the device 
shall be within the reach of the driver. While the 
device is activated, a continuous or intermittent 
signal audible to the driver shall sound. The 
audible signal may be equipped with a timing 
device requiring the signal to sound for at least 60 
seconds. If a timing device is used, it shall auto- 
matically recycle every time the service entry door 
is opened while the engine is running and the 
manual override is engaged. 

S6 Test Procedures. 

S6.1 Reflectivity Test. When tested under the 
condhions specified in S6.2 (b), (c), and (d) of 
Federal motor vehicle safety standard 125, Warn- 
ing Devices, (49 CFR 571.125), the retroreflective 
materials shall meet the criteria specified in table 
1. 

TABLE 1 — Minimum Specific Intensity Per 
Unit Area (SIA) 
(Candelas per Footcandle Per Square Foot) 
Type III Retroreflecsive Element Material 

A — Glass Bead Retroreflective Element Material 



B — Prismatic Retroreflective Element Material 

Observation Angle (°) ^nl^eT"^) "^''"'^ ^^^ 



Observation 

(°) 


Angle 


Entrance 
Angle (°) 


White 


Red 


0.2 




-4 


250 


45 


0.2 




+30 


150 


25 


0.5 




-4 


95 


15 


0.5 




+30 


65 


10 



0.2 


-4 


250 


45 


0.2 


+30 


95 


13.3 


0.5 


-4 


200 


25 


0.5 


30 


65 


10 



S6.2 Lighting Tests. 

56.2.1 Color. The procedure shall be done in 
accordance with the Society of Automotive Engi- 
neers (SAE) J578, Color Specification (May 
1988), 1990 SAE Handbook, Society of Auto- 
motive Engineers, Inc. Along with the incorpora- 
tion by reference in S6.2.3, this incorporation by 
reference was approved by the Director of the 
FEDERAL REGISTER in accordance writh 5 
U.S.C. 552(a) and 1 CFR part 51. Copies may be 
obtained from the Society of Automotive Engi- 
neers, 400 Commonwealth Drive, Warrendale, PA 
15096-0001. Copies may be inspected at Docket 
Room, National Highway Traffic Safety Adminis- 
tration, 400 Seventh Street, SW., Washington, DC 
20590 or at the office of the FEDERAL REG- 
ISTER, 800 North Capitol Street, NW., suite 700, 
Washington, DC. When visually compared to the 
light einitted from a filter/ source with a combina- 
tion of chromaticity coordinates as explained in 
SAE J578, Color Specification (May 1988), within 
specific boundaries [y = 0.33 (yellow boundary) 
and y = 0.98 — x (purple boundaiy)] the color of 
light emitted from the test object shall not be less 
saturated (paler), yellower, or purpler. The test 
object shall be placed perpendicular to the light 
source to simulate lamps on stop signal arms. In 
making visual comparisons, the light from the test 
object shall light one portion of a comparison field 
and the light from the filter/source standard shall 
light an adjacent area. To make a valid visual 
comparison, the two fields to be viewed shall be 
of near equal luminance. 

56.2.2 Flash Rate. [The lamps on each side of 
the stop signal ami, when operated at the manu- 
facturer's design load, shall flash at a rate of 60 
to 120 flashes per minute with a current "on" 
time of 30 to 75 percent. The total of the percent 
current "on" time for the two terminals shall be 
between 90 and 110. (57 F.R. 40131— September 2, 
1992. Effective: September 2, 1992)] 



PART 131-2 



> 



S6.2.3 Vibration, Moisture, Dust, Corrosion, shall meet, the criteria for vibration, moisture, 

Photometry, and Warpage Tests. The proce- dust, corrosion, photometry, and warpage in SAE 

dure shall be done in accordance with the Society J57S, Tests for Motor Vehicle Lighting Devices 

of Automotive Engineers (SAE) J575, Tests for and Components, (July 1983) and SAE J1133, 

Motor Vehicle Lighting Devices and Components, School Bus Stop Arm, (April 1984) under the test 

(July 1983) and Society of Automotive Engineers conditions specified herein. 
(SAE) J1133, School Bus Stop Arm, (April 1984), 

1990 SAE Handbook, Society of Automotive 56 F.R. 20363 

Engineers, Inc. Lamps and hghting components IVIay3, 1991 



I 



PART 131-3 



i 



i 



i 



PREAMBLE TO AN AMENDMENT TO FEDERAL MOTOR VEHICLE 

SAFETY STANDARD NO. 213 

Child Restraint Systems 

(Docket No. 74-09; Notice 26) 
RIN: 2127-AD46 



ACTION: Final rule. 

SUMMARY: This rule amends Standard 213. Child 
Restraint Systems, to require manufacturers of 
child restraints to provide a postage paid registra- 
tion form with each seat. The rule also amends the 
standard to require manufacturers to provide 
information to purchasers about the importance of 
registering the restraint, as well as information 
necessary to enable subsequent owners to register 
the restraint. In addition to amending Standard 
213, this rule adds a new Part 588 in title 49, 
CFR, that requires manufacturers to keep records 
of the names and addresses of persons who have 
returned a registration form. 

These requirements will improve the effective- 
ness of manufacturer campaigns to recall child 
restraints that contain a safety-related defect or 
fail to conform to Standard 213 by requiring 
manufacturers to take steps that will increase their 
ability to inform owners of particular child 
restraints about defects or noncompliances in 
those restraints and by encouraging child restraint 
owners to register their restraints. The require- 
ments will also assist NHTSA in determining 
whether a child safety seat manufacturer has com- 
plied with its notification re.sponsibilities estab- 
lished by the National Traffic and Motor Vehicle 
Safety Act. 

This rulemaking proceeding commenced in 
response to a December 1989 petition for rule- 
making from the Center for Auto Safety and 
Consumer Action of San Francisco. 

EFFECTIVE DATE: The amendment is effective 
March 9, 1993. 

SUPPLEMENTARY INFORMATION: 

General introduction 
This rule amends Standard 213 to establish a 
registration program for child restraint systems. 



The rule requires manufacturers to provide a 
standardized, postage-paid registration form with 
each restraint system. Manufacturers of built-in 
restraints installed in new vehicles are excluded 
from the requirement because the manufacturers 
are able to identify the vehicle owners through 
motor vehicle registration files and directly notify 
them of a recall concerning the built-in restraints. 

The rule standardizes the text and layout of the 
registration form to increase the likelihood that a 
purchaser will register the restraint. On each 
form, manufacturers must preprint their return 
address, along with information identifying the 
model name or number of the restraint to which 
the form is attached. The form must be attached 
to the restraint to ensure that a purchaser will 
notice the form. 

This rule also requires manufacturers to keep 
records of the names and addresses of persons 
who have returned a registration form. The manu- 
facturers must maintain the record for at least six 
years from the date of manufacture of the seat. 

NHTSA proposed the registration program in a 
notice of proposed rulemaking (NPRM) published 
on February 19. 1991 (56 FR 6603). Today's rule 
differs from the NPRM in various respects. The 
registration form is simplified. The labeling on 
the restraint must include both an address and a 
telephone number for the manufacturer. Cost esti- 
mates are slightly higher. The recordkeeping 
requirement of six years from the restraint's date 
of manufacture is two years less than was pro- 
posed. These and other changes are discussed fur- 
ther below. 

This rule is intended to improve the percentage 
of recalled restraints that are fixed in a recall 
campaign for a noncompliance or defect. During 
1981-1991, almost 18 million child restraints were 
recalled. During this period, about 13 percent of 
the child restraints involved in completed recall 
campaigns were reported as "campaigned units." 



PART 571: S 213— PRE-73 



Campaigned units refer to those child restraints 
that were reported remedied as well as those 
restraints either removed from sale to the public 
or removed from use by the public. (During 1981- 
1989, approximately 6 million restraints were 
recalled. About 10.5 percent of the restraints 
involved in completed recall campaigns were 
reported as campaigned units during this period. 
During 1990-1991, almost 12 million child 
restraints were recalled. Only about 1 1 percent of 
the restraints involved in completed recall cam- 
paigns were reported as campaigned during this 
period.) In general, this indicates that the child 
restraint campaign rate is considerably lower than 
the campaign rate for motor vehicles (60.5 per- 
cent for 1981-1991). 

(At the time of the NPRM, the child restraint 
average campaign completion rate was 22 percent. 
That rate reflected the number of seats that had 
been campaigned at the time of the NPRM. Dur- 
ing the period 1990-1991, the average campaign 
completion rate increased to about 27 percent.) It 
should be noted that, even though the average 
campaign completion rate averaged about 27 per- 
cent during 1990-1991, for all campaigns in 
aggregate only about 11 percent of the restraints 
involved in completed recall campaigns were 
reported as campaigned. 

The low response rate for child restraints does 
not seem a consequence of a lack of interest in 
recalls on the part of the owners. The public 
responded overwhelmingly to a December 1989 
press conference by CAS on child seat recalls by 
calling NHTSA. In the eight months following 
that press conference, NHTSA's Auto Safety Hot- 
line received over 30,000 calls from concerned 
parents asking about recalls and the safety of 
child seats. This intense interest in child safety 
indicates that many owners are highly motivated 
and would return a recalled seat for a remedy, if 
they knew it had been recalled. Stated differently, 
many owners might not have had the problem 
remedied because notification of the recall failed 
to reach them. 

NHTSA proposed the registration program to 
improve the dissemination of the recall informa- 
tion directly to individual owners. In the past, 
efforts to improve notice of a recall focused on 
better disseminating the information indirectly, 
i.e., to the general public. The agency decided to 
change its focus to individual owners. If owners 



are directly notified that their seat is recalled, the 
response rate should increase. 

Pursuant to a contract with the agency, ^B 
National Analysts conducted a study of consum- ^B 
ers' attitudes about the proposed registration pro- 
gram and other child safety issues during the time 
that the agency was developinq the NPRM. A 
copy of the February 1991 report has been avail- 
able in the docket. The researchers conducted four 
group interviews ("focus groups"). Two groups 
were interviewed in Orange, California and the 
other two in Philadelphia, Pennsylvania. The 
groups were comprised of people who acquired a 
child restraint new and who use the restraint with 
their child at least once a week. The participants 
were asked to evaluate five different registration 
fomis, three of which corresponded exactly to the 
NPRM's alternative Figure 9a, options one 
through three. The alternatives differed in how 
they presented a motivational message for the 
registration form. 

National Analysts reported that participants in 
all four groups were unanimous in their support 
for a registration program. National Analysts con- 
cluded that, based on the findings from the study, 
"the great majority of child safety seat buyers are ^m 
likely to appreciate and respond to a recall reg- ^| 
istration program." The researchers reported that: 
Participants also indicated that they would be 
most likely to return a pre-addressed, postage-pre- 
paid card with an uncluttered graphic design that 
clearly and succinctly communicates the benefits 
of recall registration, differentiates itself from a 
warranty registration card, and requires minimal 
time and effort on the participant's part. "Child 
Safety Seat Registration: The Consumer View," 
National Analysts, February 1991. 

Comments on the proposal 
The agency received 22 comments on the 
NPRM, from manufacturers, researchers, church 
and consumer groups, state governments and pri- 
vate individuals. The overwhelming majority of 
the commenters supported a registration program. 
With the exceptions discussed below, the com- 
ments generally consisted of specific suggestions 
regarding the format and language of the form, 
the labeling on the restraint, and the record- 
keeping part of the rule. Evenflo, Cosco and 
Chrysler Corporation (a manufacturer of built-in ^B 
systems) expressed concerns about the effective- ^H 
ness of registration programs. Evenflo and Cosco 



PART 571; S 213— PRE-74 



also had cost concerns, which will be discussed in 
the section on "Costs." 

Evenflo believed that a registration program 
would not be effective. Evenflo indicated that a 
registration program for child restraints can be 
compared to the "mandatory" registration 
requirements that Congress in 1982 specifically 
provided that the agency could not apply to 
independent tire dealers. See, 158(b) of the 
National Traffic and Motor Vehicle Safety Act of 
1966. The mandatory registration program had 
required all tire dealers, including independent 
dealers, to obtain and send specified information 
(i.e., the purchaser's name and address, the 
dealer's name and address, and the identification 
numbers of the tires) to the tire manufacturer. 
("Independent tire dealers" means tire dealers 
and distributors whose businesses are not owned 
or controlled by a tire manufacturer or brand 
name owner.) 

Compliance with the mandatory registration 
was uneven. While virtually all tires on new 
vehicles were registered, about half of all replace- 
ment tires were registered. Independent dealers 
had registered only 20 percent of the requirement 
tires they sold. 

With the goals of improving cne registration 
rate for tires sold by independent dealers and less- 
ening the burden on the dealers. Congress prohib- 
ited NHTSA from requiring those dealers to com- 
ply with the mandatory registration program. In 
place of the mandatory program for the dealers. 
Congress directed NHTSA to establish a vol- 
untary tire registration process. In the voluntary 
process, which is in effect today, the independent 
tire dealer furnishes a standardized registration 
fonn to each purchaser after the dealer has first 
filled in the tire identification number on the 
form. Purchasers wishing to register their tire fill 
in their name and address on the form and mail 
the completed form to the tire manufacturer. The 
form's postage is paid by the purchaser. The reg- 
istration rate for the voluntary tire registration 
program is about 1 1 percent. 

In response to Evenflo, NHTSA disagrees that 
the proposed registration process for child 
restraints is comparable to the mandatory program 
that had applied to independent tire dealers. In 
contrast, the proposed child restraint program has 
some similarities to the voluntary tire registration 
program that Congress directed NHTSA to adopt 
for the independent dealers. They are similar 



because in both cases, the semi-completed reg- 
istration form is provided to the purchaser. Per- 
sons wishing to register their product may then do 
so by filling in their name and address and mail- 
ing the completed form to the restraint manufac- 
turer. 

However, even though similarities would exist 
between the two programs, NHTSA does not 
believe that the voluntary tire program is a good 
surrogate for what might happen in the child 
restraint program. First, in the child registration 
program: (a) every child restraint will be provided 
with a registration form attached to it; and (b) 
every registration form will describe to purchasers 
why the form should be filled and returned to the 
child restraint manufacturer. As previously men- 
tioned, even though registration rates for 
independent tire dealers was about 1 1 percent, a 
consumer survey indicated that only 22 percent of 
these dealers' customers had received registration 
fomis from their dealers, and that over 80 percent 
of the independent dealers' customers did not 
remember the dealer explaining the reasons why 
the registration form should be returned to the 
manufacturer. Second, consumers seem to be far 
more likely to be concerned with child safety than 
with tires, and therefore, they are more apt to fill 
in a registration form on child restraints than on 
tires. Third, the child restraint registration form is 
postage paid, a feature that the National Analysts 
study showed should have a positive effect on 
registration rates. Other information also shows 
the positive effect of providing the postage. 
According to information from the Consumer 
Product Safety Commission, warranty cards are 
returned for chain saws at a rate of 20 to 30 per- 
cent without postage paid; 40 percent with post- 
age paid. Because of these differences, NHTSA 
does not believe the voluntary tire registration 
program is a good surrogate for what might hap- 
pen in the child registration program. 

Several commenters said that the registration 
process would be more effective if it involved 
more the retailer who sells the restraint to the 
purchaser. The CAS suggested that the process 
should "require consumers to register the child 
restraint at time of purchase and as a condition of 
the sale." The Coalition for Consumer Health and 
Safety said that the registration form should be 
"returned to the retailer at the point of sale, 
instead of enclosed with the seat to be mailed in 
by the consumer." Advocates for Highway and 



PART 571; S 213— PRE-75 



Auto Safety also believed that the form should be 
completed by the consumer with the assistance of 
the retailer at the time of purchase. 

The NPRM explained why the agency did not 
propose a seller registration process. The pre- 
amble stated: 

In deciding whether to propose mandating 
registration by sellers or a lesser alternative, the 
agency was mindful that the Vehicle Safety Act 
does not provide NHTSA with explicit authority 
to require mandatory registration of child safety 
seats — i.e., to require sellers to register all seat 
purchases. Because of these concerns, and 
because child safety seats are sold to the public 
through a complex distribution system involving 
the manufacturer, major warehouse distributors, 
local distributors, and a wide variety of retail out- 
lets, NHTSA concluded that a registration pro- 
gram for seats would have a greater likelihood of 
success in actual practice if the responsibility for 
registering were placed primarily on the manufac- 
turer (to provide the card and registration 
information) and the first owner (to fill out the 
card and mail it). 56 FR at 6604. 

NHTSA continues to believe that mandatory 
registration would be undesirable for the reasons 
stated in the NPRM. Further, a comparison can be 
made to the tire registration program. Congress 
found mandatory tire registration to be overly 
burdensome for independent businesses. The 
manufacture, distribution and sale of child seats is 
accomplished through a complex distribution sys- 
tem involving numerous retail outlets, large and 
small. A mandatory registration program could 
impose substantial burdens on these retailers. 

Chrysler expressed concerns about the need for 
registration. Chrysler stated, "we do question the 
need for and value of the proposed registration 
requirements, given that the agency's estimate for 
card return rate is about 20 to 40 percent, and no 
estimate is offered for the probable recall 
response rate." Chrysler also stated that, because 
the card return rate might be no higher than 20 
to 40 percent, "the manufacturer should be 
allowed the flexibility to determine for each 
instance how owners are to be notified, taking 
into account the nature of the particular defect or 
cause of noncompliance." The agency does not 
have information that would indicate the potential 
reduction in injuries or fatalities resulting from a 
registration requirement. The NPRM requested 
comments about instances where a child was 



injured in a safety seat that had been recalled by 
the manufacturer, but not fixed before the 
accident. No information was provided. Neverthe- ^n 
less, the agency believes there is a need for reg- ^| 
istration, to improve the notice end of a recall 
campaign. Today's registration requirements 
standardize the form to increase the likelihood 
that the purchaser will register. Today's require- 
ments will increase the likelihood that the reg- 
istrant will hear of a recall and realize that the 
recall pertains to the seat. These requirements 
address the problems referred to by Safety Belt 
Safe U.S.A. in its comment: "the vast majority of 
safety seat owners either do not learn of the 
recall/repair message; or.. .do not realize that pub- 
licized recall campaigns apply to them." These 
problems may have kept the recall response rate 
low. 

Several factors might work to optimize the reg- 
istration rate for the child restraint program. First 
of all, the public concern for child safety should 
have a decidedly positive effect on the return rate. 
Also, the child restraint registration form is 
conspicuous to the purchaser and is postage paid, 
features that should have a positive effect on reg- 
istration rates. 

With regard to flexibility, Chrysler implied that ^^ 
the registration program would obviate the need ^ 
for public notice of a recall. NHTSA disagrees. 
Section 153(c)(3) of the Safety Act authorizes 
NHTSA to require the notification to be provided 
to known purchasers of the child restraint and to 
the general public. The agency anticipates that it 
would be appropriate to require public notice of 
the recall, in addition to direct notification of reg- 
istrants, to ensure that notice is provided to the 
extent possible to owners who did not register, or 
to those whose address on registration records is 
not current or complete. 

Cosco also had concerns about the program's 
effectiveness. Cosco said that the effectiveness of 
registration is lessened because "a significant 
number of restraints are passed down from family 
to family, sold in garage sales, etc." 

NHTSA proposed the registration program 
keeping in mind that child restraints are fre- 
quently acquired "secondhand," as Cosco stated. 
To address that situation, the agency proposed 
labeling requirements to infonn secondhand own- 
ers how to register with the manufacturer. When ^ 
the secondhand owners have registered, they can ^ 
be directly notified by the manufacturer if the 



PART 571; S 213— PRE-76 



restraint is recalled. Thus, the purpose of the reg- 
istration program would be fulfilled for second- 

A hand owners through the labeling provisions. 

^ The wording of the exclusion of built-in 

restraints has been slightly changed from the pro- 
posal. The proposal excluded "a built-in child 
restraint system installed in a vehicle by the 
vehicle manufacturer." The rule excludes a "fac- 
tory-installed buih-in child restraint system" from 
the registration requirements, and defines the term 
in S4 of Standard 213 as "a built-in child 
restraint system that was installed in a motor 
vehicle at the time of its delivery to a dealer or 
distributor for distribution." The change from the 
NPRM is intended only to simplify the wording 
of the requirements portion of the standard. 

1. Standardized Registration Form. 

The NPRM proposed requirements to increase 
the likelihood that the purchaser will notice the 
form, fill it in and mail it. 

Attached form. The NPRM proposed that the 
form be attached to a "contactable surface" (the 
term is defined in S4) of the restraint so that the 
purchaser must, as a practical matter, notice and 

^ handle the form after purchasing the restraint and 

B before putting it into use. 

Several commenters addressed the proposal that 
the form be attached to a contactable surface. 
Evenflo said that "the location of the forms 
within the packaging or upon the product does 
not increase the likelihood of registration. Rather, 
it turns on the education of the consumer, their 
spare time and their ready access to the U.S. 
mail." In contrast. Safety Belt Safe said having 
the form be attached so that the purchaser must 
actively detach it will make it less likely that the 
form will be lost. 

National Analysts found that respondents in the 
focus group study indicated that seeing and han- 
dling the card are important to maximize registra- 
tion rates: 

There is also strong support for the registra- 
tion card's being attached to the seat in such a 
way that it cannot be used without first removing 
the card. It is thought particularly important for 
the card to be packaged separately from instruc- 
tions, warranties and other material enclosed with 
the CSS [child safety seat]. Suggestions include 

^ directly attaching the card to the seat liner — 

W although some question whether an adhesive 
tacky enough to securely attach to the seat would 



not leave the seat sticky — or attaching it by 
means of a plastic tie, similar to those used to 
attach price tags to clothes in department stores. 

"Make it so you can't rip it off hut have to 
use scissors because then you'll read it." 

[Participant's quotation emphasized in text.] 
(Id. at 29) 

This rule adopts the requirement that the form 
must be attached to the child restraint. The 
National Analysts study indicates that the require- 
ment will improve the likelihood that the form 
will be noticed and read by the purchaser. How- 
ever, the rule permits the form to be attached to 
more surfaces than had been proposed. Under the 
NPRM, the only permissible surfaces were 
"contactable surfaces," i.e., surfaces contactable 
by a dummy's head or torso during a compliance 
test. Under the final rule, the form may be 
attached to any surface of the restraint that con- 
tacts any portion of the dummy when the dummy 
is positioned in the system in accordance with 
S6.1.2 of Standard 213. This change from the 
NPRM is made to allow more flexibility in 
selectinq a location for attaching the form. 

Under a contactable surfaces requirement, the 
form would have had to be attached to surfaces 
only contactable by a dummy's head or torso, 
since "contactable surface" in S4 is limited to 
head and torso contacts. Thus, attaching the form 
to parts of the seat cushion that contact the dum- 
my's thighs would not have been allowed. Such 
a prohibition does not appear warranted, since 
attaching the form to surfaces other than 
"contactable" ones meets the goal of the require- 
ment that the purchaser will notice and handle the 
form when detaching it. 

Te.xt and format. The NPRM sought to 
standardize the text and format of the registration 
form to increase the likelihood that the purchaser 
will fill it in. The agency proposed a two-sided, 
two-part form that consisted of a motivational 
message and boxed statement (top part) and a 
postcard that the purchaser would fill in and mail 
(bottom part). NHTSA proposed the two-part 
form to ensure that the information on the form 
can be easily read, and that the allotted space for 
the purchaser's name and address would be suffi- 
ciently large to permit the easy, legible recording 
of all the necessary information. 

Several commenters questioned the need to 
standardize the form. Cosco said that each manu- 



PART571: S 213— PRE-77 



facturer may have differing needs for the forms, 
which calls for flexibility. Ford Motor Company 
said that manufacturers should be allowed to use 
either a fold-over card or a two-part form, and 
that details of the proposed form should be 
optional to allow manufacturers the flexibility to 
design a form that would better facilitate the 
recording of the information from registrants. 

In contrast, Safety Belt Safe said that a defi- 
nite, prescribed format is desirable because it 
"fits with the public image of important, official 
forms," which will encourage people to register. 

NHTSA is requiring the form to be standard- 
ized to increase the likelihood that a purchaser 
will register. The National Analysts study showed 
that essentially the same text and format as those 
adopted in this rule were effective in presenting 
the necessary information legibly and eliciting a 
favorable response from the purchaser, factors 
that are needed to maximize registration rates. 

The focus groups widely and enthusiastically 
accepted the text and format of the parts of the 
form that did not vary among the proposed 
options {Id. at 10-14). (The reaction to the part of 
the form that varied is also discussed below.) 
National Analysts found that the participants 
unanimously praised the boxed statement (top part 
of proposed Figure 9b — the address side of the 
form). "The boxed message. ..clearly and effec- 
tively communicates what are perceived to be the 
two most critical messages contained on the reg- 
istration cards: That it is important. ..[and] [t]hat 
this is a recall registration, not a warranty card." 
Id. at 10. 

The part of the form that the purchaser fills in 
(bottom part of proposed figure 9a, the product 
identification number and purchaser information 
side) was found to draw — 

a particularly positive response because it 
requires minimal information and effort to com- 
plete... CSS owners praise the fact that they are 
only required to fill in their name and 
address.... There is a strong preference to have the 
serial, model number and manufacturing date 
preprinted on the card as indicated on the proto- 
types. Nearly all want the numbers printed on the 
card. They feel that it saves them the trouble of 
looking-and that any marginal addition of time 
and effort serves as a potential barrier to comple- 
tion and return. Id. at 12-14. 



The portion of the form indicating that the reg- 
istration postcard is prestamped and preaddressed 
"is considered essential. ..Reaction to this was 
uniformly enthusiastic." Id. at 12. 

Because the focus groups' response to the 
text and format of the unvarying parts of the pro- 
posed form was extremely positive, NHTSA is 
requiring use of the text and format. Prescribing 
the text and format has the added benefit of 
ensuring that commercial matters, such as market- 
ing information, are excluded from the form. (In 
addition, the regulatory text expressly prohibits 
such information. See, 85. 8(c).) If marketing 
information were allowed to be placed on the 
forni, such information might cause purchasers to 
misidentify the registration form as a warranty 
card, which the agency seeks to avoid in view of 
National Analysts' finding that participants gen- 
erally had negative feelings toward warranty reg- 
istrations (Id. at 14). 

The rule prescribes the text and format for the 
motivational message, the part of the form that 
varied among the proposed options. National 
Analysts found that it is possible for the text and 
format of the message to elicit a negative 
response from the purchaser. The text for option 
two was widely criticized as appearing shallow or 
manipulative. Id. at 19. The text for option three 
was strongly criticized for its wording, tone and 
format. Focus group participants said that they 
would not read option three's message because of 
their dislike for the card. Id. at 20-22. These find- 
ings lead NHTSA to conclude that the text and 
format and text for the message must be pre- 
scribed so that the message itself does not 
discourage purchasers from registering. 

The motivational message has elements that 
received general support in the National Analysts 
study. Id. at 28. The text is based on option 1, 
which received the most positive response in the 
focus group testing. Id. at 15. However, the focus 
groups found the text style of option 1 too hard 
to read. They preferred a bold print, and that the 
text be arranged in more of the "bullet" style of 
option 2. The agency has revised the format in 
accordance with those preferences. 

The motivational message adopted today was 
suggested by National Analysts in its February 
1991 report. National Analysts made the sugges- 
tion after evaluating the reaction of the focus 
groups to the messages proposed as options in the 
NPRM. Contrary to one commenter's belief, 



PART 571; S 213— PRE-78 



>fHTSA did not receive National Analysts' 

^ suggestion for the "optimal" card until after the 

/■ NPRM was developed. For that reason, the opti- 

^ mal card was not among those proposed in the 

NPRM. However. NHTSA placed the National 

Analysts report in the public docket when the 

NPRM was published, to make the card and the 

report publicly available for review. See item 

number three in the NPRM docket, 74-09-N20. 

One commenter suggested that the card should 
have a sentence in Spanish that directs the reader 
to a resource for a translated version of the reg- 
istration form. The effect of such a requirement 
would be to require manufacturers to have forms 
available in Spanish. The burden of such a 
requirement on manufacturers does not appear 
warranted, for the reasons discussed in the agen- 
cy's November 20, 1990 denial of Texas's peti- 
tion for rulemaking on requirinq Spanish instruc- 
tions for child restraints. 55 FR 48262. 

The focus group study showed that participants 

reacted favorably to the idea of being assured by 

the manufacturer that their names would not be 

placed on a mailing list if they registered their 

^ restraints. Although the agency is not restricting 

M use of the names, it expects that manufacturers 

^ will respect owners' preferences that their names 

be kept separate from other customer lists. 

This rule specifies a minimum size for the form 
so that the part to be returned to the manufacturer 
would be mailable as a postcard. That part of the 
form, i.e., the postcard part, and the part of the 
form to which the postcard is attached must both 
be not less than 3 1/2 by 5 inches, and have a 
thickness of not less than 0.007 inches and not 
more than 0.0095 inches. These dimensions are 
taken from postal regulations for cards mailable 
without envelopes under first class postage. 

2. Labeling requirements. 

The NPRM proposed requirements to enable 
owners of secondhand restraints to register. The 
NPRM proposed that each restraint (other than 
factory-installed built-in ones) must be perma- 
nently labeled with information about the impor- 
tance of registration, and instructions for tele- 
phoning or mailing the necessary registration 
information to the manufacturer. In addition, the 
^ labeling would have to include infomiation about 

" NHTSA's Auto Safety Hotline. The proposal also 

included requirements that the registration 



information be provided in the printed instructions 
that accompany the restraint. 

Several commenters said that the proposed 
labeling is too long for the limited space available 
on the restraint, or has words that imply that the 
restraint is unsafe. NHTSA has shortened and 
revised the message in response to those com- 
ments. Some commenters suggested a new text 
and format and other changes (e.g., using a tri- 
angular warning symbol) that they believed would 
more effectively urge the purchaser to register. 
The agency reviewed the suggestions, but could 
not conclude that the suggestions improved what 
had been proposed, tested in the focus groups and 
revised for this rule. 

Fisher Price said that labeling the NHTSA Hot- 
line number is unnecessary since the owner can 
contact the manufacturer about recalls. The 
agency disagrees. The Hotline number is nec- 
essary to increase the public's awareness of that 
recall information resource. Also, consumer com- 
plaints to the Hotline have historically provided 
NHTSA an important source of data on safety- 
related defects. For that reason, the agency 
requires vehicle manufacturers to include the Hot- 
line in the vehicle owner's manual. See 49 CFR 
Part 575. NHTSA is requiring the Hotline number 
on each child restraint to ensure that the Hotline 
can be readily used by each owner, even persons 
owning secondhand restraints that are missing the 
instructions. 

This rule also requires manufacturers to provide 
a mailing address and telephone number on the 
label. The NPRM proposed either an address or 
telephone number, but several commenters said 
that both should be required to enable the owner 
to contact the manufacturer in more than one 
way. The CAS said that two companies (Virso/ 
Pride-Trimble and Century) recently changed their 
toll-free telephone numbers which made it more 
difficult for owners to contact the companies. 
CAS stated, "Requiring both company address 
and telephone number will help consumers get the 
information they need." NHTSA is requiring both 
an address and telephone number to make it 
easier for a person to register. 

Readers should note that Standard 213's label- 
ing requirements are further amended by a final 
rule published elsewhere in today's edition of the 
Federal Register. That rulemaking relates to a 
warning label requirement in the standard. In 
addition, NHTSA published an NPRM to amend 



PART 571; S 213— PRE-79 



certain labeling and other requirements for built- 
in restraint systems. 57 FR 870; January 9, 1992. 
Any amendments that might ultimately be 
adopted based on the January 1992 notice may 
modify existing labeling requirements, including 
the requirements adopted today. 

3. Recordkeeping. 

This rule establishes a new Part 588 in title 49, 
CFR, to require manufacturers to establish a 
record of registrants and maintain this record for 
at least six years from the date of manufacture of 
the seat. The record includes the name and mail- 
ing address of each registrant, and the model 
name or number and date of manufacture (month, 
year) of the restraint. 

The notice proposed an eight year period, but 
comments were requested on whether a shorter 
period, e.g., six years, should be required. Com- 
menters were sharply divided about the record- 
keeping requirement. Commenters suggested a 
length of recordkeeping ranging from four to 10 
years. 

The agency is adopting a six year requirement 
because NHTSA's records indicate that all 
restraints recalled to date were recalled within six 
years of the production date of the seat. (As 
stated above, during 1981-1991, almost 18 million 
child restraints were recalled. The average length 
of time between date of production and date of 
recall was about 28 months.) Some commenters 
said that a 10 year requirement is warranted 
because restraints more than 10 years old are still 
being used. NHTSA does not agree that those 
restraints, relatively few in number, justify record- 
keeping for longer than six years, given the aver- 
age age of recalled child restraints. NHTSA is 
concerned that a period longer than six years 
could impose an unwarranted recordkeeping bur- 
den on manufacturers. 

Costs. 

The agency has revised its cost estimates for 
this rulemaking. The NPRM and preliminary 
regulatory evaluation (PRE) estimated that the 
rule would have an average cost impact of $0.25 
to $0.31 per seat. The estimated cost was $0.13 
to $0.19 for high volume sales. $0.33 to $0.39 for 
medium volume sales, and $0.93 to $0.99 for low 
volume sales. The estimate included the cost for 
providing and attaching the registration form, 
labeling the restraint, recordkeeping, and provid- 



ing postage. The ranges in the cost estimate were 
based on a 20 percent to 40 percent return rate for 
the forms. 

Evenflo and Cosco disagreed with NHTSA's 
cost estimates. Evenflo said that the estimated 
cost for the low volume manufacturer was too 
low. Evenflo also said that the agency's estimate 
does not account for the cost doubling or tripling 
for each level of the distribution chain through 
which the restraint passes. "The ultimate cost to 
the consumer (assuming that the cost is passed on 
the consumer) will actually be three to ten times 
the estimated $1 cost." 

Cosco said that the agency's estimated costs 
are too low. Cosco believed that the true manu- 
facturing costs would be about $1.00 per seat. 
"This cost translates into a retail price increase of 
as much as 10 percent for the moderately priced 
restraints and considerably more than that for 
lower-priced booster seats and infant-only 
restraints, which very well might result in lower 
purchases of new car seats." 

NHTSA contacted Evenflo and Cosco for 
information about their cost estimates. Evenflo 
provided information showing some of the basis 
for its estimate. Cosco did not. 

The agency used the information from Evenflo 
to revise the cost estimates. The final regulatory 
evaluation for this rule discusses the cost esti- 
mates in detail. The evaluation, available in the 
docket, explains that NHTSA did not agree with 
some of Evenflo's assumptions about costs. For 
example, the manufacturer's estimate for postage 
costs was very high. However, Evenflo's informa- 
tion enabled NHTSA to estimate that the rule will 
cost $0.47 to $0.52 per restraint for high volume 
manufacturers, and $0.95 to $1.26 for medium 
volume manufacturers. These costs are based on 
a manufacturing cost of $0.20 to $0.22 per 
restraint for high volume manufacturers, and 
$0.40 to $0.53 for medium volume manufacturers. 
The agency determined the retail cost increase 
based on Evenflo's information that the markup 
from manufacturing cost to retail price is 2.37 
times. 

These costs were based on a 30 to 40 percent 
return rate for the forms. The agency has decided 
to change the estimated return rate for the child 
restraint registration forms from 20 to 40 percent 
in the NPRM, to 30 to 40 percent, since, as 
explained above the percentage of the remedied 
seats has increased. 



PART 571; S 213— PRE- 



Nomenclature unchanged. 
^ The NPRM proposed a nomenclature change to 
'■ Standard 213, to replace the term "child restraint 
system" with "child safety seat." Two com- 
menters supported the change. About nine com- 
menters ranging from manufacturers to research- 
ers to safety groups adamantly opposed it. Many 
of the commenters opposing the change said the 
term child safety seat could mislead consumers 
into believing that the device will provide 
absolute protection in a crash. Manufacturers said 
that such an expectation of absolute protection 
could result in severe liability implications for 
them in the event a child is injured or killed in 
the device. Some commenters said that the term 
child safety seat is not descriptive enough to 
make clear that it covers devices such as car beds, 
vests and harnesses. As a result, the term would 
be confusing in Standard 213. 

By proposing the nomenclature change, the 
agency sought to get consumers to better under- 
stand the importance of the seat to the child's 
safety in the automobile and on aircraft. NHTSA 
did not intend to change manufacturers' potential 
^ legal liability, nor did NHTSA intend to unsettle 
B or confuse the current understanding concerning 
which devices are included within the term "child 
restraint systems." While the effectiveness of 
child restraints is beyond question in view of data 
indicating they reduce a child's risk of death or 
serious injury by 70 percent, the agency agrees 
that the proposed nomenclature change could be 
confusing, and defers to commenters' assessment 
that the change might have unintended, undesir- 
able effects on manufacturers' legal liability. 
NHTSA is therefore retaining the term "child 
restraint system" in Standard 213. 

The final rule does not have any retroactive 
effect. Under section 103(d) of the National Traf- 
fic and Motor Vehicle Safety Act (15 U.S.C. 
1392(d)), whenever a Federal motor vehicle safety 
standard is in effect, a state may not adopt or 
maintain a safety standard applicable to the same 
aspect of performance which is not identical to 
the Federal standard. Section 105 of the Act (15 
U.S.C. 1394) sets forth a procedure for judicial 
review of final rules establishing, amending or 
revoking Federal motor vehicle safety standards. 
I That section does not require submission of a 
petition for reconsideration or other administrative 
proceedings before parties may file suit in court. 



In consideration of the foregoing, NHTSA 
amends 49 CFR Part 571 as set forth below: 

1. S4 is amended by adding the following defi- 
nition: 

Factory-installed built-in child restraint system 
means a built-in child restraint system that was 
installed in a motor vehicle at the time of its 
delivery to a dealer or distributor for distribution. 

2. S5.5.1 is revised to read as follows: 

55.5.1 Each add-on child restraint system shall be 
permanently labeled with the information specified 
in S5.5.2(a) through (m). 

3. S5.5.2 is amended by replacing the reference 
to paragraph "(1)" in the introductory paragraph 
with a reference to paragraph "(m)," by 
redesignating the existing text in paragraph (m) as 
paragraph (n), and by adding new paragraph (m), 
to read as follows: 

55.5.2 The information specified in paragraphs (a) 
through (m) of this section shall be stated in the 
English language and lettered in letters and num- 
bers that are not smaller than 10 point type and 
are on a contrasting background. 



(m) The following statement, inserting an 
address and telephone number: "Child restraints 
could be recalled for safety reasons. You must 
register this restraint to be reached in a recall. 
Send your name, address and the restraint's model 
number and manufacturing date to {insert 
address) or call {insert telephone number). For 
recall information, call the U.S. Government's 
Auto Safety Hotline at 1-800-424-9393 (202-366- 
0123 in D.C. area)." 

(n) Child restraint systems that are certified as 
complying with the provisions of section S8 shall 
be labeled with the statement "THIS 
RESTRAINT IS CERTIFIED FOR USE IN 
MOTOR VEHICLES AND AIRCRAFT." This 
statement shall be in red lettering, and shall be 
placed after the certification statement required by 
paragraph (e) of this section. 

4. S5.5.4 is revised to read as follows: 

S5.5.4 Each built-in child restraint system shall be 
permanently labeled with the information specified 
in S5.5.5(a) through (j) so that it is visible when 



PART 571; S 213— PRE-81 



the seat is activated for use as specified in S5.6.2. 
and, except a factory-installed built-in restraint, 
shall be permanently labeled with the information 
specified in S5.5.5(k). 

5. S5.5.5 is amended by revising the introduc- 
tory text and adding paragraph (k) to read as fol- 
lows: 

S5.5.5 The information specified in paragraphs (a) 
through (k) of this section shall be stated in the 
English language and lettered in letters and num- 
bers that are not smaller than 10-point type and 
are on a contrasting background. The information 
specified in paragraphs (a) through (j) shall be 
printed in the vehicle's owner's manual. 



(k) The following statement, inserting an 
address and telephone number: "Child restraints 
could be recalled for safety reasons. You must 
register this restraint to be reached in a recall. 
Send your name, address and the restraint's model 
number and manufacturing date to (insert 
address) or call (insert telephone number). For 
recall information, call the U.S. Government's 
Auto Safety Hotline at 1-800-424-9393 (202-366- 
0123 in D.C. area)." 

6. S5.6 would be amended by adding para- 
graph S5.6.1.7 and S5. 6.2.2, to read as follows: 

S5.6 Printed instructions for proper use. 



S5.6.1.7 The instructions shall include the follow- 
ing statement, inserting an address and telephone 
number: "Child restraints could be recalled for 
safety reasons. You must register this restraint to 
be reached in a recall. Send your name, address 
and the restraint's model number and manufactur- 
ing date to (insert address) or call (insert tele- 
phone number). For recall information, call the 
U.S. Government's Auto Safety Hotline at 1-800- 
424-9393 (202-366-0123 in D.C. area)." 



6.2.2 The instructions for each built-in child 
restraint system, except a factory-installed 
restraint, shall include the following statement, 
inserting an address and telephone number: 
"Child restraints could be recalled for safety rea- 
sons. You must register this restraint to be reached 
in a recall. Send your name, address and the 
restraint's model number and manufacturing date 
to (insert address) or call (insert telephone num- 
ber). For recall information, call the U.S. Govern- 
ment's Auto Safety Hotline at 1-800-424-9393 
(202-366-0123 in D.C. area)." 



* * * * 



7. A new paragraph S5.8 is added to 571.213 
to read as follows: 

S5.8 Infomiation requirements — registration form. 

(a) Each child restraint system, except a fac- 
tory-installed built-in restraint system, shall have 
a registration foiTn attached to any surface of the 
restraint that contacts the dummy when the 
dummy is positioned in the system in accordance 
with S6. 1.2 of Standard 213. 

(b) Each form shall: 

(1) Consist of a postcard that is attached at 
a perforation to an informational card; 

(2) Conform in size, content and format to 
Figures 9a and 9b; and 

(3) Have a thickness of at least 0.007 inches 
and not more than 0.0095 inches. 

(c) Each postcard shall provide the model name 
or number anddate of manufacture (month, year) 
of the child restraint system to which the form is 
attached, shall contain space for the purchaser to 
record his or her name and mailing address, shall 
be addressed to the manufacturer, and shall be 
postage paid. No other infonnation shall appear 
on the postcard, except identifying information 
that distinguishes a particular child restraint sys- 
tem from other systems of that model name or 
number may be preprinted in the shaded area of 
the postcard, as shown in figure 9a. 

Figures 9a and 9b are added to 571.213. 

57 F.R. 41428 
Septmber 10, 1992 



PART 571; S 213— PRE-82 



-► 5" minimum — 



FOR YOUR CHILD'S CONTINUED SAFETY 

Please take a few moments to promptly fill out and return the 
attached card. 

Although child restraint systems undergo testing and evaluation, 
it is possible that a child restraint could be recalled. 

In case of recall, we can reach you only if we have your name 
and address, so please send in the card to be on our recall list 



Please fill this card out and mail it NOW, 
while you are thinking about it. 

it's already addressed and we've paid the postage. 



Tear off and mail this part 



Consumer: Just fin in your name and address. 

Your name 

Your street address 

City stale Zip Code 

CHILD RESTRAINT REGISTRATION CARD 



RESTRAINT MODEL XXX 
SERIAL NUMBER YYYY 
MANUFACTURED ZZ-ZZ-19ZZ 




y 



Preprinted 

message to 
.^consumer: bold 
'typeface, caps 

and lower case 

minimum 12 point 

type. 



FOLD / PERFORATION 



Minimum 10% 
screen tint. 

Preprinted or 
stamped child 
safety seat 
model name or 
number and date 
of manufacture. 



Figure 9a— Registration Form for Child Systems— Product Identification Number and Purchaser 

Information Side. 



PART 571; S 213— PRE-83 



3.5" 
minimum 



IMPORTANT 



In case of a recall, we can reach you only if we 
have your name and address. You MUST send in 
the attached card to be on our recall list 



We've already paid the postage. 
Do it today. 



X 




NO POSTAGE 

NECESSARY 

IF MAILED 

IN THE 

UNITED STATES 



3,5" 
minimum 



MANUFACTURER 
POST OFFICE BOX 0000 
ANYTOWN, ST 12345-6789 



Block letters 
(sans serif)— Bold 
minimum 48 point 
type, caps. 



Minimum 10°/ 
screen tint 



Preprinted 
message to 
consumer; bold 
typeface, caps 
and lower case 
minimum 12 point 
type. 



FOLD I PERFORA TION 



Preprinted or 
stamped name 
and address of 
manufacturer or 
itsi 



Figure 9b— Registration Form for Child Restraint Systems— Address Side. 



PART 571; S 213— PRE-84 



PREAMBLE TO AN AMENDMENT TO FEDERAL MOTOR VEHICLE 
SAFETY STANDARD NO. 213 

Child Restraint Systems 

(Docket No. 74-09; Notice 27) 
RIN: 2127-AD45 



ACTION: Final rule. 

SUMMARY: This rule amends Federal Motor 
Vehicle Safety Standard 213. Child Restraint Sys- 
tems, to require add-on child restraints to meet the 
requirements of the standard at each of the angles 
to which the seat back can be adjusted and at each 
of the restraint belt routing positions. This amend- 
ment improves safety by removing the possibility 
that a child restraint can be designed to transport 
a child in a motor vehicle or aircraft while the 
restraint is adjusted to a position in which the 
restraint would not comply with the standard. 

DATES: The amendment is effective on March 9, 
1993. 

SUPPLEMENTARY INFORMATION: This rule 
amends S5 of Standard 213, Child Restraint Sys- 
tems, to expand the requirements for child 
restraint systems manufactured for use in motor 
vehicles, and motor vehicles and aircraft. 

The requirements are expanded to apply to pre- 
viously-excluded adjustment positions on child 
restraints. Child restraint systems typically have 
more than one seat back angle adjustment posi- 
tion and a number of restraint belt routing posi- 
tions. Under the standard before this amendment, 
adjustment positions could be excluded from the 
excursion (S5.1.3) and seat inversion (S8.2) 
requirements of the standard if the manufacturer 
warned that the positions were not for use in 
motor vehicles or aircraft. This rule eliminates 
that exclusion of adjustment positions, regardless 
of whether the manufacturer provides a warning. 

This rule also removes the related provisions 
(S5.5.2(i), S8.1) that required manufacturers of 
restraints with excluded adjustment positions to 
identify those positions on labels attached to the 
restraints. This rule also amends the conditions 
for the dynamic systems test and the inversion 



test to clarify the effect of removing these provi- 
sions. 

The proposal for this rule was published on 
August 12, 1991 (56 FR 38105). NHTSA began 
this action in response to a petition for rule- 
making from Consumer Action (CA) and the 
Center for Auto Safety (CAS). 

Background 

This rulemaking highlights the relationship 
between the test procedures specified in Standard 
213 and the performance required of a child 
restraint system. The National Traffic and Motor 
Vehicle Safety Act requires child restraint manu- 
facturers to certify each restraint as complying 
with Standard 213. NHTSA checks the validity of 
the certification by evaluating the restraint's 
performance when tested in accordance with the 
procedures specified in the standard (S6, S8). 
Generally, the procedures for the dynamic sled 
and seat inversion tests specify that the restraint 
be installed on a simulated car or aircraft seat "in 
accordance with the manufacturer's instructions" 
provided to the consumer. (However, the proce- 
dures for the dynamic sled test require that most 
restraints must be secured using only the standard 
vehicle lap belt. See, S6. 1.2. 1.1 (a)) The proce- 
dures also specify that the test dummy used to 
test the restraint is positioned "according to the 
instructions for child positioning" provided by 
the manufacturer to the consumer. (See. e.g., 
S6. 1.2.3.1, 6.1.2.3.2 and 6.1.2.3.3.) The installa- 
tion instructions must provide a narrative discus- 
sion and diagrams to facilitate installing the 
restraint in motor vehicles or aircraft, positioning 
a child in the restraint and adjusting the restraint 
to fit the child (S5.6.1 and S8.1). 

Each adjustment position of a child restraint is 
currently subject to dynamic testing unless the 
restraints manufacturer does not intend that posi- 
tion to be used in motor vehicles or aircraft and 



PART 571; S 213 PRE-85 



expressly states that intent on a label attached to 
the restraint. If the position is not intended to be 
so used, it is excluded from the standard's occu- 
pant excursion (S5.1.3) and inversion (S8.2) 
requirements. The purpose of the excursion and 
inversion requirements is to ensure that the child 
occupant is retained within the system in a crash. 

Consumer Action and CAS requested that 
NHTSA amend Standard 213 by removing the 
provision, S5.5.2(i), which requires manufacturers 
to warn consumers, by way of a warning label on 
the restraint, against using an adjustment position 
in a vehicle if the manufacturer deems the posi- 
tion is unsuitable for such use. The petitioners 
believed that the S5.5.2(i) warning label is 
insufficient to ensure that a child restraint system 
will not be used in the restricted positions in a 
motor vehicle. It appeared that the basis for the 
petition was the petitioners' belief that warning 
labels are generally ineffective. 

NHTSA issued a notice of proposed rule- 
making (NPRM) to further consider the issue of 
restricted adjustment positions. NHTSA did not 
agree with the petitioners that warning labels are 
generally insufficient to produce desired behav- 
iors. However, the agency was concerned about 
positions that are unsuitable for vehicle use, yet 
are made a part of a child restraint system for no 
reason that outweighs the likelihood that the seat 
will be misused and the risk to safety unaccept- 
ably increased. (56 FR at 38106.) 

NHTSA developed a proposal to achieve the 
purpose of the requested amendment. With regard 
to restraints for motor vehicles, NHTSA proposed 
to amend S5.1.3, Occupant excursion, to remove 
the provision that excludes the restricted positions 
from the excursion requirement. Since the exclu- 
sion would be removed, NHTSA also proposed to 
remove S5.5.2(i), the labeling provision for 
restricting a position. To make clear the effect of 
these amendments, NHTSA proposed to amend 
S5 to require each restraint to "meet the require- 
ments in [S5] at all adjustment positions (includ- 
ing, but not limited to each seat back angle 
adjustment position and each restraint belt anchor- 
age and routing position), when tested in accord- 
ance with S6.1" of Standard 213. 

With regard to restraints for aircraft, the NPRM 
proposed similar amendments. The NPRM pro- 
posed to remove the provision in Standard 213 
that excludes restricted adjustment positions from 



the inversion test requirement (S8.2) and to 
remove the warning label requirement in S8.1. ^ 

In issuing the NPRM, NHTSA believed that jj| 
most manufacturers had ceased designing child 
restraints with adjustment positions not intended 
for motor vehicle and aircraft use. However, the 
agency tentatively concluded the amendments 
were needed to ensure that no restricted position 
would be included in future restraint systems. Id. 

Comments on the NPRM 
NHTSA received comments from CAS, Advo- 
cates for Highway and Auto Safety, Cosco, Ford 
Motor Company, and the University of Michigan. 
These entities generally supported the NPRM, 
with comments relating to particular issues raised 
by the proposal. 

EjfectofSS 

Cosco and the University of Michigan sug- 
gested that the language of the proposed amend- 
ment to S5 was unclear and overbroad. Cosco 
said that a number of adjustment positions on its 
child restraints could be unintentionally affected 
by the proposed S5, and that convertible restraints 
might be especially affected. (Convertible 
restraints are restraints designed for use by both ^ 

infants and toddlers. For most convertible 
restraints, certain restraint adjustment positions 
are designed for infants only, while other posi- 
tions are suitable for toddlers only.) Emphasizinq 
that the NPRM stated convertible restraints serve 
a safety need, Cosco argued that their manufac- 
ture should be not prohibited. 

Cosco gave several examples of how it 
believed that the proposed language of S5 would 
create uncertainty about the permissibility of cer- 
tain adjustment positions on convertible restraints. 
Cosco said that its "Dream Ride" restraint is a 
"car seat/car bed with an upright, rear-facing 
position and fully reclined, side-facing position." 
The instructions for the restraint state that it 
should not be used in a front-to-back position 
when fully reclined, i.e., placed in a vehicle so 
that its and the vehicle's longitudinal axes are 
parallel. 

The commenter believed that the proposed lan- 
guage would subject the fully reclined position to 
Standard 213 requirements in the front-to-back 
position on the standard seat assembly. Cosco | 

suggested that S5 should expressly pennit manu- 
facturers to "designate ... that certain weights and 



PART 571: S 213 PRE- 



seating positions are not acceptable under certain 
conditions, as long as there are no adjustment 
^ positions available which cannot be used in motor 
" vehicles under any conditions." 

To address Cosco's concerns, NHTSA has 
made several changes. The agency has revised the 
amendment to S5. The amendment retains the 
existing statement in S5 about child restraint 
requirements: 

Each child restraint system certified for use 
in motor vehicles shall meet the requirements 
in this section when, as specified, tested in 
accordance with S6.1. 
In addition, the agency is adding a statement 
specifying that each add-on system shall meet the 
requirements of S5 at each of the restraint's seat 
back angle adjustment positions and restraint belt 
routing positions, when the restraint is oriented in 
the direction recommended for use (e.g., forward, 
rearward or laterally) pursuant to S5.6, and used 
with the test dummy specified in S7 of the stand- 
ard. 

Under the first sentence in S5, the orientation 
and adjustment of a child restraint for compliance 
testing purposes is determined based upon the 
^ instructions given by manufacturers to consumers 
i regarding the installation and use of that restraint. 
The second sentence qualifies the first sentence 
by limiting the extent to which a manufacturer's 
instructions affect how and to what extent a child 
restraint is subject to testing under the standard. 
Under the second sentence, regardless of the 
manufacturer's instructions, a child restraint is 
subject to testing in all seat back angles and belt 
routing positions. However, a manufacturer's 
instructions about a matter such as restraint ori- 
entation will still affect compliance testing. For 
example, if a manufacturer's instructions state that 
a car bed is to be installed side-to-side (per- 
pendicular to the vehicle's longitudinal axis), but 
not front-to-back (parallel to that axis), the car 
bed will be subject to testing in the side-to- side 
orientation only. 

It does not appear, however, that the originally 
proposed amendment to S5 would have caused 
the seat positioning problems Cosco described for 
its Dream Ride restraint. The proposed text 
retained the present provision in S5 that restraints 
are "tested in accordance with S6.1," the section 
^ in the standard that specifies the test conditions 
W and procedures for the dynamic systems test. 
Under S6.1, a restraint is installed on a simulated 



vehicle seat in accordance with the manufactur- 
er's instructions. A restraint that is designed to be 
adjusted to different configurations for different 
child weights is oriented forward, rearward or lat- 
erally, depending on the manufacturer's instruc- 
tions for using the restraint. 

The University of Michigan (UM) suggested S5 
would be clearer if it stated: "Each child restraint 
system certified for use in motor vehicles shall 
meet the requirements in this section at each 
adjustment position (...) in at least one type of 
vehicle (ground or aircraft) when tested in accord- 
ance with the procedures of S6.1 for at least one 
specified range of child weight." As amended 
today, S5 is similar to UM's suggested text. How- 
ever, the agency has not adopted the "ground or 
aircraft" language suggested by the commenter. 
When a manufacturer certifies its restraint as 
complying with the requirements for restraints for 
aircraft, the manufacturer states: "THIS 
RESTRAINT IS CERTIFIED FOR USE IN 
MOTOR VEHICLES AND AIRCRAFT." 
(S5.5.2(m); emphasis added.) An adjustment posi- 
tion that meets Standard 213 for aircraft use but 
not for vehicle use would not be acceptable under 
the standard. 

Othei- amendments 
This rule makes conforming changes to the test 
procedures for the excursion and inversion 
requirements. Currently, the test dummy used to 
test to these requirements is positioned in the 
restraint according to the manufacmrer's instruc- 
tions for child positioning. Under today's amend- 
ment, each of the restraint's seat back angles and 
belt routing positions will be subject to testing, 
notwithstanding the manufacturer's instructions 
not to use those adjustment positions in vehicles 
or aircraft. 

Aircraft use 

Cosco commented that the proposed amend- 
ment to the requirements for restraints certified 
for aircraft use would have a negative impact on 
its Dream Ride restraint. NHTSA disagrees. 

Cosco said it currently informs the consumer 
that the restraint should be used on aircraft only 
in the partially upright (rear-facing) position. 
Cosco said that it does not recommend the fully 
reclined position on aircraft since two aircraft 
seats are needed to accommodate the restraint in 
that adjustment position and consumers are 
unlikely to purchase those seats. Cosco indicated 



PART 571; S 213 PRE-87 



that the Dream Ride perfonns adequately in the 
car bed position, if the two aircraft seats are used. 
The commenter was concerned that it would have 
to eliminate the fully reclined position because 
the position is one that is not intended for use in 
aircraft. 

NHTSA does not seek to have Cosco eliminate 
the fully reclined position on its restraint, or 
remove the Dream Ride from the models of 
restraints certified for both motor vehicles and 
aircraft. Safety is furthered by the availability of 
restraints manufactured for both vehicles and air- 
craft. 

NHTSA does seek to ensure through today's 
amendment to the aircraft requirements that each 
seat back angle and belt routing position in 
restraints manufactured for both vehicles and air- 
craft passes the inversion requirement when tested 
according to the procedures in the standard. 
Cosco indicated that the Dream Ride, fully 
reclined, would pass the inversion test while 
fully-reclined and positioned crosswise, on two 
aircraft seats. If that is the case, the restraint 
already complies with the standard's amended air- 
craft requirements. As long as the restraint passes 
while fully reclined and positioned crosswise, the 
existence of that adjustment position does not 
prohibit Cosco from manufacturing and selling 
that child restraint. Further, nothing prohibits 
Cosco from recommending in its information to 
consumers that the seat not be used in that ori- 
entation on aircraft. Thus, the restraint must meet 
the inversion test in all of its back angles and belt 
routing positions. For example, the Dream Ride 
could be tested fully reclined with the six-month- 
old dummy while positioned crosswise, on two 
aircraft seats, even if Cosco recommends the fully 
reclined position not be used on aircraft. 

Built-in restraint systems 
Ford said the proposed amendments to S5 
could complicate testing of built-in child restraints 
that form part of a reclining vehicle seat. Ford 
stated: 

Built-in child restraints can be installed in 
vehicle seats that can be adjusted to positions 
that are not intended for use while the vehicle 
is moving. For example, many vehicle seats 
can be reclined to allow weary drivers and pas- 
sengers to rest at highway rest areas. 
Ford suggested that the proposed amendment 
expressly apply to add-on restraints only. The 



commenter believed such application was 
intended by the agency, since no mention was 
made in the preamble for the NPRM about built- 
in restraints. 

Ford also asked about an apparent discrepancy 
between the effect of the proposed S5 on built-in 
restraints and the specified test conditions (S6.1.1) 
for testing the restraints. The proposed S5 would 
have required built-in restraints to meet the stand- 
ard's requirements "at all adjustment positions" 
when tested in accordance with the conditions and 
procedures of S6.1. However, under S6.1, if a 
specific vehicle is used (the second of two stand- 
ard test devices that can be used, at the manufac- 
turer's option, to test a built-in system), a built- 
in system is tested with the vehicle seat "in the 
manufacturer's nominal design riding position." 
Stated differently, S6. 1 provides for testing only 
one adjustment position. 

Ford is correct that the agency intended only to 
address add-on systems in this rulemaking action. 
NHTSA did not consider how the proposed 
amendment would affect adjustment positions on 
built-in seats. For those seats, a reclining vehicle 
seat back may also be the seat back of a child 
restraint built into the vehicle seat. 

A built-in system that is part of a seat with a 
reclining seat back would probably fail to meet 
the standard if the seat back were reclined and if 
today's rule applied to it. Such an amendment 
could have required some redesigning of seats. 
The agency is uncertain whether there is suffi- 
cient reason to disallow the reclining feature. 
Reclining seats let weary drivers and passengers 
rest at highway rest areas (as discussed by Ford 
in its comment). Indeed, NHTSA has observed 
that some reclining seat backs in vans recline all 
the way down to the horizontal position so as to 
create a sleeping surface stretching from the rear 
of the third seating surface to the front of the sec- 
ond seating surface. Reclining seats also provide 
for easier loading of the vehicle. 

Use of a built-in restraint when the vehicle seat 
back is reclined at a sharp angle would be 
undesirable. However, until the agency learns that 
vehicles being driven with children in such 
reclined positions occurs frequently enough to 
become a significant problem, the relative merits 
of the reclining vehicle seat need not be further 
addressed. There is sufficient justification for the 
reclinability of such seats to warrant their exclu- 
sion from today's S5 amendments. However, 



PART 571; S 213 PRE-88 



NHTSA recommends that manufacturers warn 
consumers against using an adjustment position 
on a built-in restraint while the vehicle is in 
motion if the position cannot provide adequate 
protection. 

In response to an issue raised by Ford in its 
comment, today's rule adopts a technical amend- 
ment to the standard's test conditions for built-in 
restraints. As stated above, Standard 213 permits 
manufacturers the option of choosing to test a 
buih-in system with the specific vehicle shell or 
the specific vehicle. (S6. 1.1. 1(a).) Ford pointed 
out that the conditions under which a built-in sys- 
tem is tested using the shell are inconsistent with 
those under which the vehicle is tested. 

The conditions are specified in much greater 
details for the vehicle test than the shell test. 
Some of the conditions are appropriate for the 
vehicle and not for the shell, e.g., vehicle loading 
specifications. However, many of the conditions 
specified in the vehicle test are relevant for the 
shell test but are not specified for the latter. For 
example, conditions for the longitudinal and verti- 
cal seat positioning, and seat back adjustment 
position, are relevant yet unspecified. 

As a practical matter, the lack of specifications 
is inconsequential. The test procedures for built- 
in restraints direct NHTSA to '"activate the 
restraint in the specific vehicle shell or the spe- 
cific vehicle, in accordance with the manufactur- 
er's instructions provided in the vehicle owner's 
manual in accordance with S5.6.2." (See 
S6. 1.2. 1.1 and S6.1.2.I.2.) Under these instruc- 
tions, the vehicle seat that contains the built-in 
child restraint generally would be adjusted as the 
manufacturer directs, for both the vehicle and the 
shell tests. 

This rule makes the test conditions for the 
vehicle and shell tests consistent, in response to 
Ford's request that the conditions be clarified. 
The amendment is merely technical; the agency 
believes there will be no changes in the manner 
in which built-in restraints are tested. 

Other comments 
NHTSA stated in the NPRM that the agency 
conducted an informal survey of 15 restraint sys- 
tems, and did not find any currently being manu- 
factured that is labeled with the S5.5.2(i) warning. 
56 FR at 38106. Both CAS and Advocates for 
Highway-and Auto Safety (Advocates) said that 
NHTSA should survey all child seat manufactur- 



ers to determine whether restraints are being sold 
with restricted adjustment positions. 

NHTSA does not believe an additional survey 
is necessary. Child restraint manufacturers did not 
question the validity of the agency's survey, 
except to point out the issue about built-in 
restraints, discussed above. An additional survey 
is unlikely to yield knowledge more useful than 
the information that the agency already possesses. 

CAS and Advocates commented also on issues 
that were outside the scope of the rulemaking 
proposal. They concurred with NHTSA that 
convertible restraints should continue to be avail- 
able to consumers. However, both organizations 
suggested further large-scale testing of the 
restraints by NHTSA. CAS said the agency 
should determine whether the seats "provide ade- 
quate protection in any adjustment position." 
Advocates urged NHTSA to conduct tests on 
whether convertible seats are being properly used 
by the consumer. CAS and Advocates also com- 
mented on improving Standard 213's labeling 
requirements. Both said the agency should guide 
the industry toward developing improved 
consumer information on the appropriate use of a 
restraint system. 

NHTSA regards these comments as suggestions 
for future rulemaking. The agency has placed 
copies of the comments in NHTSA docket 74-09- 
N21, which relates to planned research and pos- 
sible upgrades to Standard 213. 

Typographical correction 
No comments were received on the proposed 
correction of S5.3.1. The correction is made in 
this rule. 

Concurrent amendments 

Readers should note that Standard 213's label- 
ing requirements are further amended by a final 
rule published elsewhere in today's edition of the 
Federal Register. That rulemaking relates to an 
owner registration requirement for child restraint 
systems. In addition, NHTSA published an 
NPRM to amend certain labeling and other 
requirements for built-in restraint systems. 57 FR 
870; January 9, 1992. Any amendments that 
might ultimately be adopted based on the January 
1992 notice may modify existing labeling require- 
ments, including the requirements adopted today. 

This final rule does not have any retroactive 
effect. Under § 103(d) of the National Traffic and 



PART 571:8 213 PRE-89 



Motor Vehicle Safety Act (15 U.S.C. 1392(d)), 
whenever a Federal motor vehicle safety standard 
is in effect, a state may not adopt or maintain a 
safety standard applicable to the same aspect of 
performance which is not identical to the Federal 
standard. Section 105 of the Act (15 U.S.C. 1394) 
sets forth a procedure for judicial review of final 
rules establishing, amending or revoking Federal 
motor vehicle safety standards. That section does 
not require submission of a petition for 
reconsideration or other administrative proceed- 
ings before parties may file suit in court. 

In consideration of the foregoing, NHTSA 
amends 49 CFR part 57 1 as set forth below. 

1. The authority citation for part 571 continues 
to read as follows: 

Authority. 15 U.S.C. 1392, 1401, 1403, 1407; 
delegation of authority at 49 CFR 1.50. §571.213 
[Amended] 

2. The introductory text of S5 is revised to read 
as follows: 

S5 Requirements for child restraint systems 
certified for use in motor vehicles. Each child 
restraint system certified for use in motor vehicles 
shall meet the requirements in this section when, 
as specified, tested in accordance with S6.1 and 
this paragraph. Each add-on system shall meet the 
requirements at each of the restraint's seat back 
angle adjustment positions and restraint belt rout- 
ing positions, when the restraint is oriented in the 
direction recommended by the manufacturer (e.g., 
forward, rearward or laterally) pursuant to S5.6, 
and tested with the test dummy specified in S7. 

3. S5.1.3 is revised to read as follows: 

S5.1.3 Occupant excursion. When tested in 
accordance with S6.1, each child restraint system 
shall meet the applicable excursion limit require- 
ments specified in S5. 1.3.1- S5.1.3.3. 

4. S5.3.1 is revised to read as follows: 



S5.3.1 Each add-on child restraint system shall 
have no means designed for attaching the system 
to a vehicle seat cushion or vehicle seat back and 
no component (except belts) that is designed to be 
inserted between the vehicle seat cushion and 
vehicle seat back. 



5. S5.5.2(i) is removed and reserved. 

6. S5.5.5(g) is revised to read as follows: 



(g) The statement specified in paragraph (1), _ 

and if appropriate, the statement in paragraph (2): £m 

(1) WARNING! FAILURE TO FOLLOW THE 
MANUFACTURER'S INSTRUCTIONS ON 
THE USE OF THIS CHILD RESTRAINT SYS- 
TEM CAN RESULT IN YOUR CHILD STRIK- 
ING THE VEHICLE'S INTERIOR DURING A 
SUDDEN STOP OR CRASH. 

(2) In the case of each built-in child restraint 
system which is not intended for use in the motor 
vehicle at certain adjustment positions, the follow- 
ing statement, inserting the manufacturer's adjust- 
ment restrictions. 

DO NOT USE THE ADJUSTMENT 

POSITION(S) OF THIS CHILD RESTRAINT 
WHILE THE VEHICLE IS IN MOTION. 



7. S6. 1.1. 1(a) through the introductory text of 
S6. 1.1. 1(c) is revised to read as follows: 



S6. 1.1. 1(a) The test device for add-on restraint 
systems is the standard seat assembly specified in 
S7.3. The assembly is mounted on a dynamic test 
platform so that the center SORL of the seat is fl 
parallel to the direction of the test platform travel 
and so that movement between the base of the 
assembly and the platform is prevented. 

(b) The test device for built-in child restraint 
systems is either the specific vehicle shell or the 
specific vehicle. 

(l)(i) The specific vehicle shell, if selected for 
testing, is mounted on a dynamic test platform so 
that the longitudinal center line of the shell is par- 
allel to the direction of the test platform travel 
and so that movement between the base of the 
shell and the platform is prevented. Adjustable 
seats are in the adjustment position midway 
between the forwardmost and rearmost positions, 
and if separately adjustable in a vertical direction, 
are at the lowest position. If an adjustment posi- 
tion does not exist midway between the 
forwardmost and rearmost position, the closest 
adjustment position to the rear of the midpoint is 
used. Adjustable seat backs are in the manufactur- 
er's nominal design riding position. If such a 
position is not specified, the seat back is posi- 
tioned so that the longitudinal center line of the ^ 
child test dummy's neck is vertical, and if an W 
instrumented test dummy is used, the acceler- 



PART 571; S 213 PRE-90 



ometer surfaces in the dummy's head and thorax, 
as positioned in the vehicle, are horizontal. If the 
vehicle seat is equipped with adjustable head 
restraints, each is adjusted to its highest adjust- 
ment position. 

(ii) The platform is instrumented with an accel- 
erometer and data processing system having a fre- 
quency response of 60 Hz channel class as speci- 
fied in Society of Automotive Engineers Rec- 
ommended Practice J211 JUN80 "Instrumentation 
for Impact Tests." The accelerometer sensitive 
axis is parallel to the direction of test platform 
travel. 

(2) For built-in child restraint systems, an alter- 
nate test device is the specific vehicle into which 
the built-in system is fabricated. The following 
test conditions apply to this alternate test device. 



***** 
In S6.1.1, S6.1.1.5 is added to read as fol- 



lows: 



S6. 1.1.5 In the case of add-on child restraint 
systems, the restraint shall meet the requirements 
of S5 at each of its seat back angle adjustment 
positions and restraint belt routing positions, when 
the restraint is oriented in the direction rec- 
ommended by the manufacturer (e.g., forward, 
rearward or laterally) pursuant to S5.6, and tested 
with the test dummy specified in S7. 
9. S8.1 is revised to read as follows: 
S8.1 Installation instructions. Each child 
restraint system manufactured for use in aircraft 



shall be accompanied by printed instructions in 
English that provide a step-by-step procedure, 
including diagrams, for installing the system in 
aircraft passenger seats, securing a child in the 
system when it is installed in aircraft, and adjust- 
ing the system to fit the child. 

10. S8.2 is revised to read as follows: 
S8.2 Inversion test. When tested in accordance 
with S8.2.1 through S8.2.5, each child restraint 
system manufactured for use in aircraft shall meet 
the requirements of S8.2.1 through S8.2.6. The 
manufacturer may, at its option, use any seat 
which is a representative aircraft passenger seat 
within the meaning of S4. Each system shall meet 
the requirements at each of the restraint's seat 
back angle adjustment positions and restraint belt 
routing positions, when the restraint is oriented in 
the direction recommended by the manufacturer 
(e.g., facing forward, rearward or laterally) pursu- 
ant to S8.1, and tested with the test dummy speci- 
fied in S7. If the manufacturer recommendations 
do not include instructions for orienting the 
restraint in aircraft when the restraint seat back 
angle is adjusted to any position, position the 
restraint on the aircraft seat by following the 
instructions (provided in accordance with S5.6) 
for orienting the restraint in motor vehicles. 
Issued on: September 4, 1992. 

Howard M. Smolkin 
Executive Director 

57 F.R. 41423 
September 10, 1992 



PART 571 :S 213 PRE-91 



FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 213 

Child Restraint Systems, Seat Belt Assemblies, and Anchorages 

(Docket No. 74-9; Notice 26) 
RIM: 2127-AD46 



51. Scope. This standard specifies requirements 
for child restraint systems used in motor vehicles 
and aircraft. 

52. Purpose. The purpose of this standard is to 
reduce the number of children killed or injured in 
motor vehicle crashes and in aircraft. 

53. Application. This standard applies to child 
restraint systems for use in motor vehicles and air- 
craft. 

54. Definitions. Add-on child restraint system 
means any portable child restraint system. 

Booster seat means a child restraint which con- 
sists of only a seating platform that does not 
extend up to provide a cushion for the child's 
back or head. 

Built-in child restraint system means any child 
restraint system which is an integral part of a pas- 
senger car. 

Car bed means a child restraint system 
designed to restrain or position a child in the 
supine or prone position on a continuous flat sur- 
face. 

Child restraint system means any device, 
except Type I or Type II seat belts, designed for 
use in a motor vehicle or aircraft to restrain, seat, 
or position children who weigh 50 pounds or less. 

Contactable swface means any child restraint 
system surface (other than that of a belt, belt 
buckle, or belt adjustment hardware) that may 
contact any part of the head or torso of the appro- 
priate test dummy, specified in S7, when a child 
restraint system is tested in accordance with S6.1. 
\_Factory-installed built-in child restraint system 
means a built-in child restraint system that was 
installed in a motor vehicle at the time of its 
delivery to a dealer or distributor for distribution. 
(57 F.R. 41428— September 10, 1992. Effective: 
March 9, 1993)] 



Representative aircraft passenger seat means 
either a Federal Aviation Administration approved 
production aircraft passenger seat or a simulated 
aircraft passenger seat conforming to Figure 6. 

Seat orientation reference line or SOR means 
the horizontal line through Point Z as illustrated 
in Figure lA. 




SORL— SEAT ORIENTATION REFERENCE LINE (HORIZONTAL) 

Figure 1 A— SORL Location on the Standard 
Seat 

Specific vehicle shell means the actual vehicle 
model part into which the built-in child restraint 
system is fabricated, including the complete 
surroundings of the built-in system. If the built- 
in child restraint system is manufactured as part 
of the rear seat, these surroundings include the 
back of the front seat, the interior rear side door 
panels and trim, the rear seat, the floor pan, the 
B and C pillars, and the ceiling. If the built-in 
system is manufactured as part of the front seat, 
these surroundings include the dashboard; the 
steering wheel, column, and attached levers and 
knobs; the "A" pillars; any levers and knobs 
installed in the floor or on a console; the interior 
front side door panels and trim; the front seat; the 
floor pan; and the ceiling. 

Torso means the portion of the body of a 
seated anthropomorphic test dummy, excluding 
the thighs, that lies between the top of the child 



PART 571; S 213-1 



(Rev. 9/10/92) 



restraint system seating surface and the top of the 
shoulders of the test dummy. 

S5. Requirements for child restraint systems 
certified for use in motor vehicles. [Each child 
restraint system certified for use in motor vehicles 
shall meet the requirements in this section when, 
as specified, tested in accordance with S6.1. and 
this paragraph. Each add-on system shall meet the 
requirements at each of the restraint's seat back 
angle adjustment positions and restraint belt rout- 
ing positions, when the restraint is oriented in the 
direction recommended by the manufacturer (e.g., 
forward, rearward or laterally) pursuant to S5.6, 
and tested with the test dummy specified in S7. 
(57 F.R. 41423— September 10, 1992. Effective: 
March 9, 1993)] 

S5.1 Dynamic performance. 

55.1.1 Child restraint system integrity. When 
tested in accordance with S6.1, each child restraint 
system shall; 

(a) Exhibit no complete separation of any load 
bearing structural element and no partial separa- 
tion exposing either surfaces with a radius of less 
than '/4 inch or surfaces with protrusions greater 
than Vs inch above the immediate adjacent 
surrounding contactable surface of any structural 
element of the system; 

(b) If adjustable to different positions, remain 
in the same adjustment position during the testing 
as it was immediately before the testing; and 

(c) If a front facing child restraint system, not 
allow the angle between the system's back sup- 
port surfaces for the child and the system's seat- 
ing surface to be less than 45 degrees at the 
completion of the test. 

55.1.2 Injury criteria. When tested in accord- 
ance with S6.1, each child restraint system that, in 
accordance with S5.5.2(0, is recommended for use 
by children weighing more than 20 pounds, 
shall— 

(a) Limit the resultant acceleration at the loca- 
tion of the accelerometer mounted in the test 
dummy head as specified in Part 572 such that 
the expression: 



(t2 - t.) 



shall not exceed 1,000, where a is the resultant 
acceleration expressed as a multiple of g (the 
acceleration of gravity), and ti and t2, are any two 
moments during the impacts. 

(b) Limit the resultant acceleration at the loca- 
tion of the accelerometer mounted in the test 
dummy upper thorax as specified in Part 572 to 
not more than 60 g's, except for intervals whose 
cumulative duration is not more than 3 milli- 
seconds. 

S5.1.3 Occupant excursion. [When tested in 
accordance with S6.1, each child restraint system 
shall meet the applicable excursion limit require- 
ments specified in S5. 1.3. 1-S5. 1.3.3. (57 F.R. 
41423— September 10, 1992. Effective: March 9, 
1993)] 

S5.1.3.1 Child restraint systems other than 
rear-facing ones and car beds. Each child 
restraint system, other than a rear-facing child 
restraint system or a car bed, shall retain the test 
dummy's torso within the system. 

(a) In the case of an add-on child restraint sys- 
tem, no portion of the test dummy's head shall 
pass through the vertical transverse plane that is 
32 inches forward of point Z on the standard seat 
assembly, measured along the center SORL (as 
illustrated in Figure IB), and neither knee pivot 
point shall pass through the vertical, transverse 
plane that is 36 inches forward of point Z on the 
standard seat assembly, measured along the center 
SORL. 

(b) In the case of a built-in child restraint sys- 
tem, neither knee pivot shall pass through a verti- 
cal, transverse plane that is 36 inches forward of 
the hinge point of the specific passenger car seat 
into which the system is built, measured along a 
horizontal line parallel to the vehicle's longitu- 
dinal center line and the center line of the pas- 
senger car seat. 



PART 571; S 213-2 



> 



_^Upper Torso Belt Anchorage Point 

Anchorage Point on 
Rear Package Shelf 

-O 



Rear Lap Belt 
Buckle Location 



Ref. NHTSA Drawing 
No. SAS-1000 




I 



Notes: (1 ) Upper Torso Belt Anchorae Point Located Excursion Point 

21 .4" Right or Lett of the Center SORL 
as shown in Fig. 1A 
(2) Rear Lap Belt Buckle Located 7.0" Right or 
Left of the Center SORL as shown in Fig. 1 A 

Figure 1B— Locations of Additional Belt Anchorage Points and Forward Excursion Limit 



Seatback frontal surface plane extended 



Foreward Limit 




Note: The limits 

illustrated move 
during dynamic 
testing 



Figure 1C— Rear Facing Child Restraint Forward and Upper Head Excursion Limits 

PART 571; S 213-3 



55.1.3.2 Rear-facing child restraint systems. width of not less than 6 inches, measured in the 
In the case of each rear-facing child restraint sys- horizontal plane of the height specified in para- 
tem. all portions of the test dummy's torso shall graph (a) of this section. 

be retained within the system and no portion of (c) Limits the rearward rotation of the test 

the target point on either side of the dummy's dummy head so that the angle between the head 

head shall pass through the transverse orthogonal and torso of the dummy specified in 57 when 

planes whose intersection contains the forward- tested in accordance with S6.1 is not more than 

most and top-most points on the child restraint 45 degrees greater than the angle between the 

system surfaces (illustrated in Figure IC). head and torso after the dummy has been placed 

in the system in accordance with S6. 1.2.3 and 

55.1.3.3 Car beds. In the case of car beds, all before the system is tested in accordance with 
portions of the test dummy's head and torso shall 35 j 

be retained within the confines of the car bed. 

S5.2.1.2 [A front facing child restraint system is 

S5.1.4 Bacl< support angle. When a rear-facing not required to comply with S5.2.1.1 if the target 

child restraint system is tested in accordance with point on either side of the dummy's head is below 

S6.1, the angle between the system's back support a horizontal plane tangent to the top of— 

surface for the child and the vertical shall not (a) The standard seat assembly, in the case of 

exceed 70 degrees. an add-on child restraint system, when the 

dummy is positioned in the system and the sys- 

S5.2 Force distribution. tem is installed on the assembly in accordance 

S5.2.1 Minimum head support surface-child ,. ^ t^. » .u e 

restraints other than car beds. ^ ^^\ The passenger car seat, in the case of a 

built-m child restraint system, when the system is 
activated and the dummy is positioned in the sys- 

S5.2.1.1 Except as provided in S5.2.1.2, each tem in accordance with S6.1.2. (53 F.R. 1783— 

child restraint system other than a car bed shall January 22, 1988. Effective: January, 22, 1988)] 
provide restraint against rearward movement of 

the head of the child (rearward in relation to the S5.2.2 Torso impact protection. Each child 

child) by means of a continuous seat back which restraint system other than a car bed shall comply 

is an integral part of the system and which— with the applicable requirements of S5.2.2.1 and 

(a) Has a height, measured along the system S5.2.2.2. 
seat back surface for the child in the vertical 

longitudinal plane passing through the longitu- S5.2.2.1 (a) The system surface provided for the 

dinal centerline of the child restraint systems from support of the child's back shall be flat or concave 

the lowest point on the system seating surface ^"d have a continuous surface area of not less 

that is contacted by the buttocks of the seated than 85 square inches 

dummy, as follows: ^h) Each system surface provided for support of 

[ [ the side of the child's torso shall be flat or con- 

Weight ' (in pounds) Heigiit- (in inches) ^ave and have a continuous surface of not less 

Less than ''o lb 18 t^han 24 Square inches for systems recommended 

20 lb or more, but not more than 40 lb 20 for children Weighing 20 pounds or more, or 45 

°^^ ' ^ — square inches for systems recommended for chil- 

us: S^chuVen'oVSr w^rghl^'^^""^'"^"'^' """" '''*' '"' dren weighing less than 20 pounds. 

= The height of the portion of the system seat back providing head ((,) Each horizontal CrOSS SCCtion of Cach SyS- 

restraint shall not be less than the above. .. , ■ , • r j 

tem surface designed to restrain forward move- 

(b) Has a width of not less than 8 inches meas- nient of the child's torso shall be flat or concave 
ured in the horizontal plane at the height specified and each vertical longitudinal cross section shall 
in paragraph (a) of this section. Except that a be flat or convex with a radius of curvature of the 
child restraint system with side supports extend- underlying structure of not less than 2 inches. 

ing at least 4 inches forward from the padded sur- 
face of the portion of the restraint system pro- S5.2.2.2 [Each forward-facing child restraint sys- 
vided for support of the child's head may have a tem shall have no fixed or movable surface — 

(Rev. 1/22/88) PART 571; S 213-4 



(a) Directly forward of the dummy and inter- 
sected by a horizontal line — 

( 1 ) Parallel to the 50RL, in the case of the 
add-on child restraint system, or 

(2) Parallel to a vertical plane through the 
longitudinal center line of the passenger car 
seat, in the case of the built-in child restraint 
system, and (b) Passing through any portion of 

the dummy, except for surfaces which restrain the 
dummy when the system is tested in accordance 
with S6. 1.2. 1.2, so that the child restraint system 
shall conform to the requirements of S5.1.2 and 
S5. 1.3.1. (53 F.R. 1783— January 22, 1988. Effec- 
tive: January, 22, 1988)] 

55.2.3 Head Impact protection. 

55.2.3.1 Each child restraint system, other than a 
child harness, which is recommended under 
S5.5.2(f) for children weighing less than 20 
pounds shall comply with S5.2.3.2. 

55.2.3.2 Each system surface, except for protru- 
sions that comply with S5.2.4, which is 
contactable by the dummy head when the system 
is tested in accordance with S6.1 shall be covered 
with slow recovery, energy absorbing material 
with the following characteristics: 

(a) A 25 percent compression-deflection resist- 
ance of not less than 0.5 and not more than 10 
pounds per square inch when tested in accordance 
with S6.3. 

(b) A thickness of not less than Vi inch for 
material having a 25 percent compression-deflec- 
tion resistance of not less than 1.5 and not more 
than 10 pounds per square inch when tested in 
accordance with S6.3. Materials having a 25 per- 
cent compression-deflection resistance of less than 
1.8 pounds per square inch shall have a thickness 
of not less than '^A inch. 

55.2.4 Protrusion limitation. Any portion of a 
rigid structural component within or underlying a 
contactable surface, or any portion of a child 
restraint system surface that is subject to the 
requirements of S5.2.3 shall, with any padding or 
other flexible overlay material removed, have a 
height above any immediately adjacent restraint 
system surface of not more than V» inch and no 
exposed edge with a radius of less than 'A inch. 



55.3 Installation. 

55.3.1 Each [add-on] child restraint system shall 
have no means designed for attaching the system 
to vehicle seat cushion or vehicle seat back and no 
component (except belts) that is designed to be 
inserted between the vehicle seat cushion and 
vehicle seat back. (53 F.R. 1783— January 22, 1988. 
Effective: January, 22, 1988) 

55.3.2 When installed on a vehicle seat, each 
[add-on] child restraint system, other than child 
harnesses, shall be capable of being restrained 
against forward movement solely by means of a 
Type I seat belt assembly (defined in S57 1.209) 
that meets Standard No. 208 (S57 1.208), or by 
means of a Type I seat belt assembly plus one 
additional anchorage strap that is supplied with the 
system and conforms to S5.4. (53 F.R. 1783— 
January 22, 1988. Effective: January, 22, 1988) 

55.3.3 Car beds. Each car bed shall be designed 
to be installed on a vehicle seat so that the car 
bed's longitudinal axis is perpendicular to a verti- 
cal longitudinal plane through the longitudinal 
axis of the vehicle. 

55.4 Belts, belt buckles, and belt webbing. 

S5.4.1 Performance requirements. The web- 
bing of belts provided with a child restraint system 
and used to attach the system to the vehicle or to 
restrain the child within the system shall — 

(a) After being subjected to abrasion as speci- 
fied in § 5.1(d) or 5.3(c) of FMVSS No. 209 
(§571.209), have a breaking strength of not less 
than 75 percent of the strength of the unbraided 
webbing when tested in accordance with S5.1(b) 
of FMVSS No. 209. 

(b) Meet the requirements of S4.3 (e) through 
(h) of FMVSS No. 209 (S57 1.209); and 

(c) If contactable by the test dummy torso 
when the system is tested in accordance with 
S6.1, have a width of not less than Wi inches 
when measured in accordance with S5.4.1.1. 

S5.4.1.1 Width test procedure. Condition the 
webbing for 24 hours in an atmosphere of any rel- 
ative humidity between 48 and 67 percent, and 
any ambient temperature between 70° and 77° F. 
Measure belt webbing width under a tension of 5 
pounds applied lengthwise. 



PART 571: S 213-5 



(Rev. 1/22/88) 



55.4.2 Belt buckles and belt adjustment hard- 
ware. Each belt buckle and item of belt adjust- 
ment hardware used in a child restraint system 
shall conform to the requirements of S4.3 (a) and 
S4.3 (b) of FMVSS No. 209 (S57 1.209). 

55.4.3 Belt Restraint. 

55.4.3.1 General. Each belt that is part of a 
child restraint system and that is designed to 
restrain a child using the system shall be adjust- 
able to snugly fit any child whose height and 
weight are within the ranges recommended in 
accordance with S5.5.2 (f) and who is positioned 
in the system in accordance with the instructions 
required by S5.6. 

55.4.3.2 Direct restraint. [Each belt that is part 
of a child restraint system and that is designed to 
restrain a child using the system and to attach the 
system to the vehicle shall, when tested in accord- 
ance with S6.1, impose no loads on the child that 
result from the mass of the system, or 

(a) in the case of an add-on child restraint sys- 
tem, from the mass of the seat back of the stand- 
ard seat assembly specified in S7.3, or (b) in the 
case of a built-in child restraint system, from the 
mass of any part of the vehicle into which the 
child restraint system is built. (53 F.R. 1783 — 
January 22, 1988. Effective: January, 22, 1988)] 

55.4.3.3 Seating systems. Except for child 
restraint systems subject to S5.4.3.4, each child 
restraint system that is designed for use by a child 
in a seated position and that has belts designed to 
restrain the child shall, with the test dummy speci- 
fied in S7 positioned in the system in accordance 
with S6. 1.2.3, provide: 

(a) upper torso restraint in the form of: 

(i) belts passing over each shoulder of the 
child; or 

(ii) a fixed or movable surface that complies 
with S5.2.2. 1(c), and 

(b) lower torso restraint in the form of: 

(i) a lap belt assembly making an angle 
between 45° and 90° with the child restraint 
seating surface at the lap belt attachment 
points, or 

(ii) a fixed or movable surface that complies 
with S5.2.2.1(c), and 

(c) in the case of each seating system rec- 
ommended for children over 20 pounds, crotch 
restraint in the form of: 



(i) a crotch belt connectable to the lap belt 
or other device used to restrain the lower torso, 
or ^—^ 

(ii) a fixed or movable surface that complies ^^ 
with S5.2.2.1(c). 

55.4.3.4 Harnesses. Each child harness shall: 

(a) Provide upper torso restraint, including belts 
passing over each shoulder of the child; 

(b) Provide lower torso restraint by means of 
lap and crotch belt; and 

(c) Prevent a child of any height for which the 
restraint is recommended for use pursuant to 
S5.5.2(f) from standing upright on the vehicle 
seat when the child is placed in the device in 
accordance with the instructions required by S5.6. 

55.4.3.5 Buckle Release. Any buckle in a child 
restraint system belt assembly designed to restrain 
a child using the system shall; 

(a) When tested in accordance with S6.2.1 prior 
to the dynainic test of S6.1, not release when a 
force of less than 9 pounds is applied and shall 
release when a force of not more than 14 pounds 
is applied: 

(b) After the dynamic test of S6.1, when tested 

in accordance with S6.2.3, release when a force ^^ 
of not more than 16 pounds is applied; 

(c) Meet the requirements of S4.3(d)(2) of 
FMVSS No. 209 (S57 1.209), except that the 
minimum surface area for child restraint buckles 
designed for push-button application shall be 0.6 
square inch. 

(d) Meet the requirements of S4.3(g) of 
FMVSS No. 209 (S57 1.209) when tested in 
accordance with S5.2(g) of FMVSS No. 209; and 

(e) Not release during the testing specified in 
S6.1. 

S5.5 Labeling. 

55.5.1 Each [add-on] child restraint system shall 
be permanently labeled with the information 
specified in S5.5.2 (a) through (I). (53 F.R. 1783— 
January 22, 1988. Effective: January, 22, 1988) 

55.5.2 The information specified in paragraphs 
(a)-(m) of this section shall be stated in the Eng- 
lish language and lettered in letters and numbers 
that are not smaller than 10 point type and are on 

a contrasting background. ^ 

(a) The model name or number of the system. ^ 



PART 571; S 213-6 



(b) The manufacturer's name. A distributor's 
name may be used instead if the distributor 
assumes responsibihty for all duties and liabilities 
imposed on the manufacturer with respect to the 
system by the National Traffic and Motor Vehicle 
Safety Act, as amended 

(c) The statement: "Manufactured in ," 

inserting the month and year of manufacture. 

(d) The place of manufacture (city and State, or 
foreign country). However, if the manufacturer 
uses the name of the distributor, then it shall state 
the location (city and State, or foreign country) of 
the principal offices of the distributor. 

(e) The statement: "This child restraint system 
conforms to all applicable Federal motor vehicle 
safety standards." 

(f) One of the following statements, inserting 
the manufacturer's recommendations for the 
maximum weight and height of children who can 
safely occupy the system: 

(i) This infant restraint is designed for use by 

children who weigh pounds or less 

and whose height is inches or less; 

or 

(ii) This child restraint is designed for use 

only by children who weigh between 

and pounds and whose height is 

inches or less and who are capable 

of sitting upright alone; or 

(iii) This child restraint is designed for use 

only by children who weigh between 

and pounds and are between 



_and 



inches in height. 



(g) The following statement, inserting the loca- 
tion of the manufacturer's installation instruction 
booklet or sheet on the restraint: 
WARNING! FAILURE TO FOLLOW EACH OF 
THE FOLLOWING INSTRUCTIONS CAN 
RESULT IN YOUR CHILD STRIKING THE 
VEHICLE'S INTERIOR DURING A SUDDEN 
STOP OR CRASH. 

SECURE THIS CHILD RESTRAINT WITH A 
VEHICLE BELT AS SPECIFIED IN THE 
MANUFACTURER'S INSTRUCTIONS 

LOCATED 

(h) In the case of each child restraint system 
that has belts designed to restrain children using 
them: 

SNUGLY ADJUST THE BELTS PROVIDED 
WITH THIS CHILD RESTRAINT AROUND 
YOUR CHILD. 

(i) [Reserved] 



(j) In the case of each child restraint system 
equipped with an anchorage strap, the statement: 
SECURE THE TOP ANCHORAGE STRAP 
PROVIDED WITH THIS CHILD RESTRAINT 
AS SPECIFIED IN THE MANUFACTURER'S 
INSTRUCTIONS. 

(k) In the case of each child restraint system 
which can be used in a rear-facing position, one 
of the following statements: 

(i) PLACE THIS CHILD RESTRAINT IN A 

REAR-FACING POSITION WHEN USING IT 

WITH AN INFANT; or 

(ii) PLACE THIS INFANT RESTRAINT IN 

A REAR-FACING POSITION WHEN USING 

IT IN THE VEHICLE. 

(1) An installation diagram showing the child 
restraint system installed in the right front out- 
board seating position equipped with a continu- 
ous-loop lap/shoulder belt and in the center rear 
seating position as specified in the manufacturer's 
instructions, [(m) The following statement, insert- 
ing an address and telephone number: "Child 
restraints could be recalled for safety reasons. 
You must register this restraint to be reached in 
a recall. Send your name, address and the 
restraint's model number and manufacturing date 
to (insert address) or call (insert telephone num- 
ber). For recall information, call the U.S. Govern- 
ment's Auto Safety Hotline at 1-800-424-9393 
(202-366-0123 in D.C. area)." (57 F.R. 41428— 
September 10, 1992. Effective: March 9, 1993)] 

(n) Child restraints that are certified as comply- 
ing with the provisions of section S8 shall be 
labeled with the statement "THIS RESTRAINT 
IS CERTIFIED FOR USE IN MOTOR 
VEHICLES AND AIRCRAFT". This statement 
shall be in red lettering, and shall be placed after 
the certification statement required by paragraph 
(e) of this section. 

55.5.3 The information specified in S5.5.2 (g)-(k) 
shall be located on the add-on child restraint sys- 
tem so that it is visible when the system is 
installed as specified in S5.6.1. 

55.5.4 [Each build-in child restraint system shall 
be permanently labeled with the information 
specified in S5.5.5(a) through (j), so that it is visi- 
ble when the system is activated for use as speci- 
fied in S5.6.2., and, except a factory-installed 
built-in restraint, shall be permanently labeled 
with the information specified in S5.5.5(k). (57 



PART 571: S 213-7 



(Rev. 9/10/92) 



F.R. 41428— September 10, 1992. Effective: March 
9. 1993)] 

S5.5.5 [The information specified in paragraphs 
(a) through (k) of this section shall be stated in the 
English language and lettered in letters and num- 
bers which are not smaller than 10-point type and 
are on a contrasting background. This infonnation 
specified in paragraphs (a) through (j) shall be 
printed in the vehicle owner's manual. (57 F.R. 
41428— September 10, 1992. EfTective: March 9, 
1993)] 

(a) The model name or number of the system. 

(b) The manufacturer's name. A distributor's or 
dealer's name may be used instead if the distribu- 
tor or dealer assumes responsibility for all duties 
and liabilities imposed on the manufacturer with 
respect to the system by the National Traffic and 
Motor Vehicle Safety Act, as amended. 

(c) The statement: "Manufactured in ," 

inserting the month and year of manufacture. 

(d) The place of manufacture (city and State, or 
foreign country). However, if the manufacturer 
uses the name of the distributor or dealer, then it 
shall state the location (city and State, or foreign 
country) of the principal offices of the distributor 
or dealer. 

(e) The statement: "This child restraint system 
confoims to all applicable Federal motor vehicle 
safety standards. 

(f) One of the following statements, inserting 
the manufacturer's recommendations for the 
maximum weight and height of children who can 
safely occupy the system: 

(i) This infant restraint is designed for use by 

children who weigh pounds or less and 

whose height is inches or less; 

(ii) This child restraint is designed for use 

only by children who weigh between and 

pounds and whose height is inches 

or less and who are capable of sitting upright 
alone; or 

(iii) This child restraint is designed for use 

by children who weigh between and 

pounds and are between and inches 

in height. 

(g) [The statement specified in paragraph (1), 
and if appropriate, the statement in paragraph (2): 

(i) WARNING! FAILURE TO FOLLOW 
THE MANUFACTURER'S INSTRUCTIONS 
ON THE USE OF THIS CHILD RESTRAINT 
SYSTEM CAN RESULT IN YOUR CHILD 



STRIKING THE VEHICLE'S INTERIOR 
DURING A SUDDEN STOP OR CRASH. 

(ii) In the case of each built-in child restraint sys- 
tem which is not intended for use in the motor 
vehicle at certain adjustment positions, the follow- 
ing statement, inserting the manufacturer's adjust- 
ment restrictions. DO NOT USE THE 

ADJUSTMENT POSITION(S) OF THIS CHILD 
RESTRAINT WHILE THE VEHICLE IS IN 
MOTION. (57 F.R. 41423— September 10, 1992. 
Effective: March 9, 1993)] 

(h) In the case of each build-in child restraint 
system that has belts designed to restrain children 
using them: 

SNUGLY ADJUST THE BELTS PROVIDED 
WITH THIS CHILD RESTRAINT AROUND 
YOUR CHILD. 

(i) In the case of each built-in child restraint 
which can be used in a rear, facing position, the 
following statement: 

PLACE AN INFANT IN A REAR-FACING 
POSITION IN THIS CHILD RESTRAINT. 

(j) A diagram or diagrams showing the fully 
activated child restraint system in infant and/or 
child configurations, [(k) The following state- 
ment, inserting an address and telephone number: 
"Child restraints could be recalled for safety rea- 
sons. You must register this restraint to be 
reached in a recall. Send your name, address and 
the restraint's model number and manufacturing 
date to (insert address) or call {insert telephone 
number). For recall information, call the U.S. 
Government's Auto Safety Hotline at 1-800-424- 
9393 (202-366-0123 in D.C. area)." (57 F.R. 
41428— September 10, 1992. Effective: March 9, 
1993)] 

S5.6 Printed Instructions for Proper Use. 

S5.6.1 Add-on restraint systems. Each add-on 
child restraint system shall be accompanied by 
printed installation instructions in the English lan- 
guage that provide a step-by-step procedure, 
including diagrams, for installing the system in 
motor vehicles, securing the system in the 
vehicles, positioning a child in the system, and 
adjusting the system to fit the child. 

S5.6.1.1 In a vehicle with rear designated seating 
positions, the instructions shall alert vehicle own- 
ers that, according to accident statistics, children 
are safer when properly restrained in the rear seat- 
ing positions than in the front seating positions. 



(Rev. 9/10/92) 



PART 571; S 213-8 



55.6.1.2 The instructions shall specify in general 
terms the types of vehicles, the types of seating 
positions, and the types of vehicle safety belts 
with which the add-on child restraint system can 
or cannot be used. 

55.6.1 .3 The instructions shall explain the primary 
consequences of not following the warnings 
required to be labeled on the child restraint system 
in accordance with S5.5.2(g) through (k). 

55.6.1.4 The instructions for each car bed shall 
explain that the car bed should position in such a 
way that the child's head is near the center of the 
vehicle. 

55.6.1.5 The instructions shall state that add-on 
child restraint systems should be securely belted to 
the vehicle, even when they are not occupied, 
since in a crash an unsecured child restraint sys- 
tem may injure other occupants. 

55.6.1.6 Each add-on child restraint system shall 
have a location on the restraint for storing the 
manufacturer's instructions. 

[S5.6.1.7 The instructions shall include the fol- 
lowing statement, inserting an address and tele- 
phone number: "Child restraints could be recalled 
for safety reasons. You must register this restraint 
to be reached in a recall. Send your name, address 
and the restraint's model number and manufactur- 
ing date to (insert address) or call (insert tele- 
phone number). For recall information, call the 
U.S. Government's Auto Safety Hotline at 1-800- 
424-9393 (202-366-0123 in D.C. area)." (57 F.R. 
41428— September 10, 1992. Effective: March 9, 
1993)] 
(Rev. 9/10/92) 

S5.6.2 Built-in child restraint systems. Each 
built-in child restraint system shall be accom- 
panied by printed instructions in the English lan- 
guage that provide a step-by-step procedure, 
including diagrams, for activating the built-in 
child restraint system, positioning a child in the 
system, adjusting the restraint and, if provided, the 
restraint harness to fit the child. This information 
and the information specified in S5.5.5, shall be 
included in the vehicle owner's manual. 

S5.6.2.1 The instructions shall explain the primary 
consequences of not following the manufacturer's 



warnings for proper use of the child restraint sys- 
tem in accordance with S5.5.5(f) through (i). 

[S5.6.2.2 The instructions for each built-in child 
restraint system, except a factory-installed 
restraint, shall include the following statement, 
inserting an address and telephone number: 
"Child restraints could be recalled for safety rea- 
sons. You must register this restraint to be reached 
in a recall. Send your name, address and the 
restraint's model number and manufacturing date 
to (insert address) or call (insert telephone num- 
ber). For recall information, call the U.S. Govern- 
ment's Auto Safety Hotline at 1-800-424-9393 
(202-366-0123 in D.C. area)." (57 F.R. 41428— 
September 10, 1992. Effective: March 9, 1993)] 

55.6.3 The instructions shall explain the primary 
consequences of noting following the warnings 
required to be labeled on the child restraint system 
in accordance with S5.5.2 (g)-(k). 

55.6.4 The instructions for each car bed shall 
explain that the car bed should position in such a 
way that the child's head is near the center of the 
vehicle. 

55.6.5 The instructions shall state that child 
restraint systems should be securely belted to the 
vehicle, even when they are not occupied, since in 
a crash an unsecured child restraint system may 
injure other occupants. 

55.6.6 Each child restraint system shall have a 
location on the restraint for storing the manufac- 
turer's instructions. 

S5.7 Flammability. Each material used in a child 
restraint system shall conform to the requirements 
of S4 of FMVSS No. 302 (S57 1.302). In the case 
of a built-in child restraint system, the require- 
ments of 54 of FMVSS No. 302 shall be met in 
both "in-use" and "stowed" positions. 

[S5.8 Information requirements— registration 
form. 

(a) Each child restraint system, except a fac- 
tory-installed build-in restraint system, shall have 
a registration form attached to any surface of the 
restraint that contacts the dummy when the 
dummy is positioned in the system in accordance 
with S6.1.2 of Standard 213. 

(b) Each fonn shall: 



PART 571; S 213-9 



(Rev. 9/10/92) 



(1) Consist of a postcard that is attached at 
a perforation to an informational card: 

(2) Conform in size, content and format to 
Figures 9a and 9b; and 

(3) Have a thicicness of at least 0.007 inches 
and not more than 0.0095 inches, (c) Each post- 
card shall provide the model name or number and 
date of manufacture (month, year) of the child 
restraint system to which the form is attached, 
shall contain space for the purchaser to record his 
or her name and mailing address, shall be 
addressed to the manufacturer, and shall be post- 
age paid. No other information shall appear on 
the postcard, except identifying information that 
distinguishes a particular child restraint system 
from other systems of that model name or number 
may be preprinted in the shaded area of the post- 
card, as shown in figure 9a. (57 F.R. 41428 — 
September 10, 1992. Effective: March 9, 1993)] 

S6. Test Conditions and Procedures. 

S6.1 Dynamic Systems Test. 

S6.1.1 Test Conditions. 

S6.1.1.1 [(a) The test device for add-on child 
restraint systems is the standard seat assembly 
specified in S7.3. The assembly is mounted on a 
dynamic test platform so that the center SORL of 
the seat is parallel to the direction of the test plat- 
form travel and so that movement between the 
base of the assembly and the platfomi is pre- 
vented. 

(b) The test device for built-in child restraint 
systems is either the specific vehicle shell or the 
specific vehicle. 

(l)(i) The specific vehicle shell, if selected 
for testing, is mounted on a dynamic test plat- 
form so that the longitudinal center line of the 
shell is parallel to the direction of the test plat- 
form travel and so that movement between the 
base of the shell and the platfomi is prevented. 
Adjustable seats are in the adjustment position 
midway between the forwardmost and rearmost 
position, and if separately adjustable in a verti- 
cal direction, are at the lowest position. If an 
adjustment position does not exist midway 
between the forwardmost and reaiTnost position, 
the closest adjustment position to the rear of 
the midpoint is used. Adjustable seat backs are 
in the manufacturer's nominal design riding 



position. If such a position is not specified, the 
seat back is positioned so that the longitudinal 
center line of the child test dummy's neck is 
vertical, and if an instrumented test dummy is 
used, the accelerometer surfaces in the dum- 
my's head and thorax, as positioned in the 
vehicle, are horizontal. If the vehicle seat is 
equipped with adjustable head restraints, each 
is adjusted to its highest adjustment position. 

(ii) The platform is instrumented with an 
accelerometer and data processing system hav- 
ing a frequency response of 60Hz channel class 
as specified in Society of Automotive Engi- 
neers Recommended Practice J211 JUN80 
■'Instrumentation for Impact Tests." The accel- 
erometer sensitive axis is parallel to the direc- 
tion of the test platform travel. (2) For built- 
in child restraint systems, an alternative test 
device is the specific vehicle into which the built- 
in system is fabricated. The following test condi- 
tions apply to this alternate test device. (57 F.R. 
41428— September 10, 1992. Effective: March 9, 
1993)] 

(c) For built-in child restraint systems, an alter- 
nate test device is the specific vehicle into which 
the build-in system is fabricated. Activate the sys- 
tem in accordance with the manufacturer's 
instructions provided in the vehicle owner's man- 
ual in accordance with S5.6.2. When the complete 
vehicle traveling longitudinally forward at any 
speed up to and including 30 mph, impacts a 
fixed collision barrier that is perpendicular to the 
line of travel of the vehicle, the built-in child 
restraint system shall meet the injury criteria of 
S5.1.2. The following test conditions apply to this 
alternate test device. 

(i) The vehicle is loaded to its unloaded 
vehicle weight plus its rated cargo and luggage 
capacity weight, secured in the luggage area, 
plus the appropriate child test dummy and, at 
the option of the manufacturer, an 
anthropomorphic test dummy which conforms 
to the requirements of Subpart B or Subpart E 
of Part 572 of this title for a 50th percentile 
adult male dummy placed in the front outboard 
seating position. If the built-in child restraint 
system is installed at one of the seating posi- 
tions otherwise requiring the placement of a 
Part 572 test dummy, then in the frontal bairier 
crash specified in S6. 1.1.2, the appropriate 
child test dummy shall be substituted for the 
Part 572 test dummy, but only at that seating 



(Rev. 9/10/92) 



PART 571; S 213-10 



position. The fuel tank is filled to any level 
from 90 to 95 percent of capacity. 

(ii) Adjustable seats are in the adjustment 
midway between the forward-most and rear- 
most positions, and if separately adjustable in a 
vertical direction, are at the lowest position. If 
an adjustment position does not exist midway 
between the forward-most and rear-most posi- 
tions, the closest adjustment position to the rear 
of the midpoint is used. 

(iii) Adjustable seat backs are iii the manu- 
facturer's nominal design riding position. If a 
nominal position is not specified, the seat back 
is positioned so that the longitudinal center line 
of the child test dummy's neck is vertical, and 
if an anthropomorphic test dummy is used, the 
accelerometer surfaces in the test dummy's 
head and thorax, as positioned in the vehicle, 
are horizontal. If the vehicle is equipped with 
adjustable head restraints, each is adjusted to its 
highest adjustment position. 

(iv) Movable vehicle windows and vents are, 
at the manufacturer's option, placed in the fully 
closed position. 

(v) Convertibles and open-body type vehicles 
have the top, if any, in place in the closed pas- 
senger compartment configuration. 

(vi) Doors are fully closed and latched but 
not locked. 

(vii) All instrumentation and data reduction 
is in conformance with SAE J211 JUN80. 

S6.1.1.2 [The tests are frontal barrier impact sim- 
ulations of the test platform or frontal barrier 
crashes of the specific vehicles as specified in 
S5.1 (571.208) and for; 

(a) Test Configuration I specified in S6. 1.2. 1.1, 
are at a velocity change of 30 mph with the accel- 
eration of the test platform entirely within the 
curve shown in Figure 2, or for the specific 
vehicle test with the deceleration produced in 30 
mph frontal barrier crash, (b) Test Configuration 
II specified in S6. 1.2. 1.2 are set at a velocity 
change of 20 mph with the acceleration of the test 
platform entirely within the curve shown in Fig- 
ure 3, or for the specific vehicle test with the 
deceleration produced in 20 mph frontal barrier 
crash. (53 F.R. 1783— January 22, 1988. Effective: 
January, 22, 1988)] 



ACCELERATION FUNCTION FOR AV = 30 MPH 




TIME— MILLISECONDS 



Figure 2 



ACCELERATION FUNCTION FOR AV = 30 MPH 




TIME— MILLISECONDS 

Figure 3 

56.1.1.3 In the case of add-on child restraint sys- 
tems. Type I seat belt assemblies meeting the 
requirements of Standard No. 209 (S57 1.209) and 
having webbing with a width of not more than 2 
inches are attached, without the use of retractors 
or reels of any kind, to the seat belt anchorage 
points (illustrated in Figure IB) provided on the 
standard seat assembly. 

56.1.1.4 Performance tests under S6.1 are con- 
ducted at any ambient temperature from 66° to 
78° F and at any relative humidity from 10 per- 
cent to 70 percent. 

[S6.1.1.5 In the case of add-on child restraint sys- 
tems, the restraint shall meet the requirements of 
S5 at each of its seat back angle adjustment posi- 
tions and restraint belt routing positions, when the 
restraint is oriented in the direction recommended 
by the manufacturer (e.g., forward, rearward or 
laterally) pursuant to S5.6, and tested with the test 



PART 571: S 213-1: 



(Rev. 1/22/88) 



dummy specified in S7. (57 F.R. 41423— Septem- 
ber 10, 1992. Effective: March 9, 1993)] 



S6.1.2 Dynamic Test Procedure. 

56.1.2.1 Test Configuration. 

56.1.2.1.1 Test Configuration (a) In the case of 
eacii add-on child restraint system other than a 
child harness, a booster seat with a top anchorage 
strap, or a restraint designed for use by physically 
handicapped children, install a new add-on child 
restraint system at the center seating position of 
the standard seat assembly in accordance with the 
manufacturer's instructions provided with the sys- 
tem pursuant to S5.6.1, except that the add-on 
restraint shall be secured to the standard vehicle 
seat using only the standard vehicle lap belt. A 
child harness, booster seat with a top anchorage 
strap, or a restraint designed for use by physically 
handicapped children shall be installed at the cen- 
ter seating position of the standard seat assembly 
in accordance with the manufacturer's instructions 
provided with the system pursuant to S5.6.1. 

(b) In the case of each built-in child restraint 
system, activate the restraint in the specific 
vehicle shell or the specific vehicle, in accordance 
with the manufacturer's instructions provided in 
the vehicle owner's manual in accordance with 
S5.6.2. 

56.1.2.1.2 Test Configuration II. (a) In the case 
of each add-on child restraint system which is 
equipped with a fixed or movable surface 
described in S5.2.2.2, or a booster seat with a top 
anchorage strap, install a new add-on child 
restraint system at the center seat position of the 
standard seat assembly using only the standard 
seat lap belt to secure the system to the standard 
seat. 

(b) In the case of each built-in child restraint 
system which is equipped with a fixed or mov- 
able surface described in S5.2.2.2, or a built-in 
booster seat with a top anchorage strap, activate 
the system in the specific vehicle shell or the spe- 
cific vehicle in accordance with the manufactur- 
er's instructions provided in the vehicle owner's 
manual in accordance with S5.6.2. 

56.1.2.2 Tighten all belts used to attach the add- 
on child restraint system to the standard seat 
assembly to a tension of not less than 12 pounds 
and not more than 15 pounds, as measured by a 



load cell used on the webbing portion of the belt. 
Tighten all manual vehicle belts used to secure the 
built-in child restraint system or a child to the spe- ^^ 
cific vehicle shell or specific vehicle to one of the ^* 
following tensions: 

(a) For a seat equipped with a manual adjuster 
or automatic locking retractor, not less than 12 
pounds and not more than 15 pounds, as meas- 
ured by a load cell used on the webbing portion 
of the belt; 

(b) For a seat equipped with an emergency 
locking retractor, as specified in S4.3 of Standard 
209. 

S6.1.2.3 Place in the child restraint any dummy 
specified in 57 for testing systems for use by chil- 
dren of the heights and weights for which the sys- 
tem is recommended in accordance with S5.6. 

S6.1. 2.3.1 When placing the 3-year-old test 
dummy in add-on or built-in child restraint sys- 
tems other than car beds, position the test dummy 
according to the instructions for child positioning 
provided by the manufacturer with the system in 
accordance with S5.6.1 or S5.6.2 while conform- 
ing to the following: 

(a) Holding the test dummy torso upright until ^ 
it contacts the system's design seating surface, 

place the test dummy in the seated position within 
the system with the midsagittal plane of the test 
dummy head — 

(i) coincident with the center SORL of the 

standard seating assembly, in the case of the 

add-on child restraint system, or 

(ii) vertical and parallel to the longitudinal 

center line of the specific vehicle shell or the 

specific vehicle, in the case of a built-in child 

restraint system. 

(b) Extend the arms of the test dummy as far 
as possible in the upward vertical direction. 
Extend the legs of the dummy as far as possible 
in the forward horizontal direction, with the 
dummy feet perpendicular to the centerline of the 
lower legs. 

(c) Using a flat square surface with an area of 
4 square inches, apply a force of 40 pounds, per- 
pendicular to: 

(i) the plane of the back of the standard seat 
assembly in the case of an add-on child 
restraint system, or ^ 

(ii) the back of the vehicle seat in the spe- " 
cific vehicle shell or the specific vehicle in the 



(Rev. 9/10/92) 



PART 571; S 213-12 



case of a build-in child restraint system, first 
against the dummy crotch and then at the 
■K\ dummy thorax in the midsagittal plane of the 

W dummy. For a child restraint system with a 

fixed or movable surface described in S5.2.2.2 
which is being tested under the conditions of 
test configuration II, do not attach any of the 
child restraint belts unless they are an integral 
part of the fixed or movable surface. For all 
other child restraint systems and for a child 
restraint system with a fixed or movable sur- 
face which is being tested under the conditions 
of test configuration I, attach all appropriate 
child restraint belts and tighten them as speci- 
fied in S6. 1.2.4. Attach all appropriate vehicle 
belts and tighten them as specified in S6.1.2.2. 
Position each movable surface in accordance 
with the manufacturer's Instructions provided 
in accordance with S5.6.1 or S5.6.2. 
(d) After the steps specified in paragraph (c) of 
this section, rotate each dummy limb downwards 
in the plane parallel to the dummy's midsagittal 
plane until the limb contacts a surface of the child 
restraint system or the standard seat assembly in 
the case of an add-on system, or the specific 
1^ vehicle shell or specific vehicle in the case of a 
W built-in system, as appropriate. Position the limbs, 
if necessary, so that limb placement does not 
inhibit torso or head movement in tests conducted 
under S6. 

S6. 1.2.3.2 When placing the 6-month-old dummy 
in [add-on or built-in] child restraint systems 
other than car beds, position the test dummy 
according to the instructions for child positioning 
provided with the system by the manufacturer in 
accordance with [S5.6.1 or S5.6.2] while 
conforming to the following: 

(a) With the dummy in the supine position on 
a horizontal surface, and while preventing move- 
ment of the dummy torso by placing a hand on 
the center of the torso, rotate the dummy legs 
upward by lifting the feet until the legs contact 
the upper torso and the feet touch the head, and 
then slowly release the legs but do not return 
them to the tlat surface. 

(b) Place the dummy in the child restraint sys- 
tem so that the back of the dummy torso contacts 
the back support surface of the system. For a 

\ child restraint system with a fixed or movable 

^ surface described in S5.2.2.2 which is being 

tested under the conditions of test configuration 



II, do not attach any of the child restraint belts 
unless they are an integral part of the fixed or 
movable surface. For all other child restraint sys- 
tems and for a child restraint system with a fixed 
or movable surface which is being tested under 
the conditions of test configuration I, attach all 
appropriate child restraint belts and tighten them 
as specified in S6. 1.2.4. Attach all appropriate 
vehicle belts and tighten them as specified in 
S6. 1.2.2. Position each movable surface in 
accordance with the manufacturer's instructions 
provided in accordance with [S5.6. 1 or S5.6.2.] 
If the dummy's head does not remain in the 
proper position, it shall be taped against the front 
of the seat back surface of the system by means 
of a single thickness of '/i-inch-wide paper mask- 
ing tape placed across the center of the dummy 
face, (c) Position the dummy arms vertically 
upwards and then rotate each arm downward 
toward the dummy's lower body until it contacts 
a surface of the child restraint system or the 
standard seat assembly, [in the case of an add-on 
child restraint system, or the specific vehicle shell 
or the specific vehicle in the case of a built-in 
child restraint system, ensuring that no ann is 
restrained from movement in other than the 
downward direction, by any part of the system or 
the belts used to anchor the system to the stand- 
ard seat assembly, the specific vehicle shell, or 
the specific vehicle.] (53 F.R. 1783 — January 22, 
1988. Effective: January 22, 1988) 

S6. 1.2.3.3 When placing the 6-month-old dummy 
or 3-year-old dummy in a car bed, place the 
dummy in the car bed in the supine position with 
its midsagittal plane perpendicular to the center 
SORL of the standard seat assembly and position 
the dummy within the car bed in accordance with 
instructions for child positioning provided with the 
car bed by its manufacturer in accordance with 
S5.6. 

S6.1 .2.4 If provided, shoulder and pelvic belts that 
directly restrain the dummy shall be adjusted as 
follows: 

Tighten the belts until a 2-pound force applied 
(as illustrated in Figure 5) to the webbing at the 
top of each dummy shoulder and to the pelvic 
webbing two inches on either side of the torso 
midsagittal plane pulls the webbing '/4 inch from 
the dummy. 



PART 571; S 213-13 



(Rev. 1/22/88) 



56.1.2.5 Accelerate the test platform to simulate 
frontal impact in accordance with S6. 1.1.2 (a) or 
S6. 1.1.2. (b), as appropriate. 

56.1.2.6 [For add-on child restraint systems, 
measure dummy excursion and detemiine 
conformance with the requirements specified in 

55.1 as appropriate. For built-in child restraint 
systems, measure dummy knee excursion and 
determine conformance with the requirements 
specified in S5.1 as appropriate. (53 F.R. 1783 — 
January 22. 1988. Effective: January. 22, 1988)] 

56.2 Buckle release test procedure. The belt 
assembly buckles used in the child restraint sys- 
tem shall be tested in accordance with S6.2.1 
through S6.2.4 inclusive. 

S6.2.1 Before conducting the testing specified in 
S6.1, place the loaded buckle on a hard, flat, hori- 
zontal surface. Each belt end of the buckle shall 
be pre-loaded in the following manner. The anchor 
end of the buckle shall be loaded with a 2-pound 
force in the direction away from the buckle. In the 
case of buckles designed to secure a single latch 
plate, the belt latch plate end of the buckle shall 
be pre-loaded with a 2-pound force in the direc- 
tion away from the buckle. In the case of buckles 
designed to secure two or more latch plates, the 
belt latch plate ends of the buckle shall be loaded 
equally so that the total load is 2 pounds in the 
direction away from the buckle. For push-button 
release buckles the release force shall be applied 
by a conical surface (cone angle not exceeding 90 
degrees). For push-button release mechanisms 
with a fixed edge (referred to in Figure 7 as 
"hinged button"), the release force shall be 
applied at the centerline of the button, 0.125 
inches away from the movable edge directly oppo- 
site the fixed edge, and in the direction that pro- 
duces maximum releasing effect. For push-button 
release mechanisms with no fixed edge (referred 
to Figure 7 as "floating button"), the release 
force shall be applied at the center of the release 
mechanism in the direction that produces the 



maximum releasing effect. For all other buckle 
release mechanisms, the force shall be applied on 
the centerline of the buckle lever or finger tab in 
the direction that produces the maximum releasing 
effect. Measure the force required to release the 
buckle. Figure 7 illustrates the loading for the dif- 
ferent buckles and the point where the release 
force should be applied, and Figure 5 illustrates 
the conical surface used to apply the release force 
to push-button release buckles. 

S6.2.2 After completion of the testing specified in 
S6. 1 , and before the buckle is unlatched, tie a self- 
adjusting sling to each wrist and ankle of the test 
dummy in the manner illustrated in Figure 4. 



Pull Horizontally 




Figure 4 — Buckle Release Test 

56.2.3 [Pull the sling horizontally in the manner 
illustrated in Figure 4 and parallel to the center 
SORL of the seat assembly, in the case of an add- 
on child restraint system, or parallel to the longitu- 
dinal center line of either the specific vehicle shell 
or the specific vehicle, in the case of a built-in 
child restraint system, and apply a force of 20 
pounds in the case of a system tested with a 6 
month-old dummy and 45 pounds in the case of 
a system tested with a 3 year-old dummy. (53 F.R. 
1783— January 22. 1988. Effective: January, 22, 
1988)] 

56.2.4 While applying the force specified in 
S6.2.3, and using the device shown in Figure 8 for 
push-button release buckles, apply the release 
force in the manner and location specified in 
S6.2.1 for that type of buckle. Measure the force 
required to release the buckle. 



(Rev. 1/22/88) 



PART 571; S 213-14 



S6.3 Head impact protection— energy absorb- 
ing material test procedure. 

S6.3.1 Prepare and test specimens of the energy 
absorbing material used to comply with S5.2.3 in 
accordance with the applicable 25 percent 
compression-deflection test described in the Amer- 
ican Society for Testing and Materials (ASTM) 
Standard D 1056-73, "Standard Specification for 
Flexible Cellular Materials — Sponge or Expanded 
Rubber", or D 1564-71. "Standard Method of 
Testing Flexible Cellular Materials — Slab Ure- 
thane Foam" or D1565-76 "Standard Specifica- 
tion for Flexible Cellular Materials — Vinyl Chlo- 
ride Polymer and Copolymer open-cell foams. 

S7 Test dummies. 

57.1 Six-month-old dummy. An unclothed 
"Six-month-old Size Manikin" conforming to 
Subpart D of Part 572 of this chapter is used for 
testing a child restraint system that is rec- 
ommended by its manufacturer in accordance with 
S5.6 for use by children in a weight range that 
includes children weighing not more than 20 
pounds. 

57.2 Three-year-old dummy. A three-year-old 
dummy confomiing to Subpart C of Part 572 of 
this chapter is used for testing a child restraint that 
is recommended by its manufacturer in accordance 
with S5.6 for use by children in a weight range 
that includes children weighing more than 20 
pounds. 

[(a) Built-in child restraints. When a three- 
year-old test dummy is used for testing a built-in 
child restraint, the dummy shall be assembled 
with the head assembly specified in 
§572. 16(a)(1). 

(b) Add-on child restraints. Until September 1, 
1993, when a three-year-old test dummy is used 
for testing an add-on child restraint, the dummy 
shall be assembled using, at the manufacturer's 
option, either head assembly specified in 
§ 572.16(a). Effective September 1, 1993, when a 
three-year-old dummy is used for testing an add- 
on child restraint, the dummy shall be assembled 
with the head assembly specified in 
§ 572.16(a)(1). (55 F.R. 30465— July 26, 1990. 
EfTective: August 27, 1990.] 



Insert Webbing' 

to Rest Against 

This Surface 



1/16 inch diameter wire 



I) 



•H Dimension B 



Direction of Pull 



Dimension A - Width of Webbing Plus 1/8 inch 
Dimension B - 1/2 of Dimension A 



Figure 5 — Webbing Tension Pull Device 

S7.2.1 Before being used in testing under this 
standard, the dummy is conditioned at any 
ambient temperature from 66° F to 78° F and at 
any relative humidity from 10 percent to 70 per- 
cent for at least 4 hours. 



S7.2.2 When used in testing under this standard, 
the dummy is clothed in thermal knit waffle- 
weave polyester and cotton underwear, a size 4 
long-sleeved shirt weighing 0.2 pounds, a size 4 
pair of long pants weighing 0.2 pounds and cut off 
just far enough above the knee to allow the knee 
target to be visible, and size 7M sneakers with 
rubber toe caps, uppers of dacron and cotton or 
nylon and a total weight of 1 pound. Clothing 
other than the shoes is machine-washed in 160° F 
to 180° F water and machine dried at 120° F to 
140° F for 30 minutes. 

S7.3 Standard test devices. 

(a) The standard test devices used in testing 
add-on child restraint systems under this standard 
are: 



PART 571; S 213-13 



(Rev. 7/26/90) 



(1) For testing for motor vehicle use, a 
standard seat assembly consisting of a simu- 
lated vehicle bench seat, with three seating 
positions, which is described in Drawing Pack- 
age SAS-100-1000 (consisting of drawings and 
a bill of materials); and 

(2) For testing for aircraft use, a standard 
seat assembly consisting of a representative air- 
craft passenger seat. 

(b) The standard test devices used in testing 
built-in child restraint systems under this standard 
are either a specific vehicle shell or a specific 
vehicle. 

S8. Requirements, test conditions, and proce- 
dures for child restraint systems manufactured 
for use in an aircraft. Each child restraint system 
manufactured for use in both motor vehicles and 
aircraft must comply with all of the applicable 
requirements specified in section S5 and with the 
additional requirement specified in S8.1 and S8.2. 

S8.1 Installation instructions. [Each child 
restraint system manufactured for use in aircraft 
shall be accompanied by printed instructions in 
English that provide a step-by-step procedure, 
including diagrams, for installing the system in 
aircraft passenger seats, securing a child in the 
system when it is installed in aircraft, and adjust- 
ing the system to fit the child. (57 F.R. 41423— 
September 10, 1992. Effective: March 9, 1993)] 

[S8.2 Inversion test. When tested in accordance 
with S8.2.1 through S8.2.5, each child restraint 
system manufactured for use in aircraft shall meet 
the requirements of S8.2.1 through S8.2.6. The 
manufacturer may, at its options, use any seat 
which is a representative aircraft passenger seat 
within the meaning of S4. Each system shall meet 
the requirements at each of the restraint's seat 
back angle adjustment positions and restraint belt 
routing positions, when the restraint is oriented in 
the direction recommended by the manufacturer 
(e.g., facing forward, rearward or laterally) pursu- 
ant to S8.1, and tested with the test dummy speci- 
fied in S7. If the manufacturer recommendations 
do not include instructions for orienting the 
restraint in aircraft when the restraint seat back 
angle is adjusted to any position, position the 



restraint on the aircraft seat by following the 
instructions (provided in accordance with S5.6) 
for orienting the restraint in motor vehicles. (57 i^ 
F.R. 41423— September 10, 1992. Effective: March ^ 
9, 1993)] 

S8.2.1 A representative aircraft passenger seat 
shall be positioned and adjusted so that its hori- 
zontal and vertical orientation and its seat back 
angle are the same as shown in Figure 6. 




Figure 6— Simulated Aircraft Passenger Seat 

"A" represents a 2- to 3-inch thick poly- 
urethane foam pad, 1.5-2.0 pounds per cubic foot 
density, over 0.020-inch-thick aluminum pan, and 
covered by 12- to 14-ounce marine canvas. The 
sheet aluminum pan is 20 inches wide and sup- 
ported on each side by a rigid structure. The seat 
hack is a rectangular frame covered with the alu- 
minum sheet and weighing betv^'een 14 and 15 
pounds, with a center of mass 13 to 16 inches 
above the seat pivot axis. The mass moment of 
inertia of the seat back about the seat pivot axis 
is between 195 and 220 ounce-inch-second ~. The 
seat back is free to fold forward about the pivot, 
but a stop prevents reaiward motion. The pas- 
senger safety belt anchor points are spaced 21 to 
22 inches apart and are located in line with the 
seat pivot axis. 



(Rev. 9/10/92) 



PART 571; S 213-16 



r 






I I I 2 Pounds 



7a. Single Latch Plate 
Pre-load 



Release Force 

Applicati 

Posilion 



r 




Buckle Pre-load 



Release Force 
Application Position- 
Push Button 
Mechanisms 




^ W 



m^ 



— t— 



7c. Hinged Button 

Figure 7— Pre-impact Buckle Release Force Test Set-up 



7d. Floating Button 



_____i_ 



Qi3 



Figure 8— Release Force Application Device— Push Button Release Buckles 



PART 571; S 213-17 



FOR YOUR CHILD'S CONTINUED SAFETY 

Please take a few moments to promptly fill out and return the 
attached card. 

Although child restraint systems undergo testing and evaluation, 
it is possible that a child restraint could be recalled. 

In case of recall, we can reach you only if we have your name 
and address, so please send in the card to be on our recall list 



Please fill this card out and mail it NOW, 
while you are thinking about it. 

It's already addressed and we've paid the postage. 



Tear off and mail this part 



Consumer: Just tlll in your name and address. 

Your name 



Your street address 



CHILD RESTRAINT REGISTRATION CARD 



RESTRAINT MODEL XXX 
SERIAL NUMBER YYYY 
MANUFACTURED ZZ-ZZ-19ZZ 




y 



Preprinted 

message to 
^consumer; bold 
'typeface, caps 

and lower case 

minimum 12 point 

type. 



FOLD / PERFORATION 



Minimum 10% 
screen tint. 

Preprinted or 
stamped child 
safety seat 
model name or 
number and date 
of manufacture. 



Figure 9— Registration Form for Child Systems— Product Identification Number and Purchaser 

Information Side. 

[(57 F.R. 41428— September 10, 1992. 
Effective: March 9, 1993)] 



(Rev. 9/10/92) 



PART 571; S 213-18 



) 



3.5" 
minimum 



IMPORTANT 



In case of a recall, we can reach you only if we 
have your name and address. You MUST send in 
the attached card to be on our recall list 



We've already paid the postage. 
Do it today. 




NO POSTAGE 

NECESSARY 

IF MAILED 

IN THE 

UNITED STATES 



MANUFACTURER 
POST OFFICE BOX 0000 
ANYTOWN, ST 12345-6789 



Block letters 
(sans serif)— Bold 
minimum 48 point 
type. caps. 



Minimum 10% 
screen tint 



Preprinted 
message to 
consumer; bold 
typeface, caps 
and lower case 
minimum 12 point 
type. 



FOLD / PERFORA TION 




Preprinted or 
stamped name 
and address of 
manufacturer or 
its designee. 



Figure 10— Registration Form for Child Restraint Systems— Address Side. 
[(57 F.R. 41428— September 10, 1992. Effective: March 9, 1993)] 



PART 571: S 213-19 



(Rev. 9/10/92) 



58.2.2 The child restraint system shall be attached 
to the representative aircraft passenger seat using, 
at the manufacturer's options, any Federal Avia- 
tion Administration approved aircraft safety belt, 
according to the restraint manufacturer's instruc- 
tions for attaching the restraint to an aircraft seat. 
No supplementary anchorage belts or tether straps 
may be attached; however. Federal Aviation 
Administration approved safety belt extensions 
may be used. 

58.2.3 In accordance with S6. 1.2.3.1 through 
S6. 1.2.3.3, place in the child restraint any dummy 
specified in S7 for testing systems for use by chil- 
dren of the heights and weights for which the sys- 
tem is recommended in accordance with S5.5 and 
S8.1. 

58.2.4 If provided, shoulder and pelvic belts that 
directly restrain the dummy shall be adjusted in 
accordance with S6. 1.2.4. 

58.2.5 The combination of representative aircraft 
passenger seat, child restraint and test dummy 
shall be rotated forward around a horizontal axis 
which is contained in the median transverse verti- 
cal plane of the seating surface portion of the air- 
craft seat and is located one inch below the bot- 
tom of the seat frame, at a speed of 35 to 45 
degrees per second, to an angle of 180 degrees. 
The rotation shall be stopped when it reaches that 
angle and the seat shall be held in this position for 
three seconds. The child restraint shall not fall out 



of the aircraft safety belt, nor shall the test dummy 
fall out of the child restraint at any time during the 
rotation or the three second period. The specified 
rate of rotation shall be attained in not less than 
one-half second, and not more than one second, 
and the rotating combination shall be brought to 
a stop in not less than one half second and not 
more than one second. 

S8.2.6 Repeat the procedures set forth in S8.2.1 
through S8.2.4. The combination of the represent- 
ative aircraft passenger seat, child restraint, and 
test dummy shall be rotated sideways around a 
horizontal axis which is contained in the median 
longitudinal vertical plane of the seating surface 
portion of the aircraft seat and is located one inch 
below the bottom of the seat frame, at a speed of 
35 to 45 degrees per second, to an angle of 180 
degrees. The rotation shall be stopped when it 
reaches that angle and the seat shall be held in this 
position for three seconds. The child restraint shall 
not fall out of the aircraft safety belt, nor shall the 
test dummy fall out of the child restraint at any 
time during the rotation or the three second 
period. The specified rate of rotation shall be 
attained in not less than one half second and not 
more than one second, and the rotating combina- 
tion shall be brought to a stop in not less than one 
half second and not more than one second. 

44 F.R. 72131 
December 13, 1979 



PART 571; S 213-20 



PREAMBLE TO AN AMENDMENT TO FEDERAL MOTOR VEHICLE SAFETY 

STANDARD NO. 214 
Side Impact Protection — Light Trucks, Buses, and Multipurpose Passenger 

Vehicles 

(Docket No. 88-06; Notice 19) 
RIN: 2127-AE32 



ACTION: Final rule; 
reconsideration. 



response to petitions for SUPPLEMENTARY INFORMATION: 



SUMMARY: On June 14, 1991. NHTSA published 
in the Federal Register (56 FR 27427) a final rule 
extending the quasistatic side door strength 
requirements of Federal Motor Vehicle Safety 
Standard No. 214, Side Impact Protection, to 
trucks, buses and multipurpose passenger vehicles 
with a gross vehicle weight rating of 10,000 
pounds or less. The agency established an effec- 
tive date of September 1, 1993 for the extension 
of these requirements. NHTSA received one peti- 
tion for reconsideration of the final rule, from 
General Motors (GM). The petitioner requested 
that the agency phase-in the new requirements 
instead of applying them to all of the newly cov- 
ered vehicles simultaneously. In response to GM's 
petition, NHTSA is establishing a brief phase-in 
period for the new requirements and is delaying 
by one year the effective date for double opening 
cargo doors, doors with no windows, and certain 
contoured doors. The agency notes, however, that 
it is adopting a different phase-in schedule from 
that suggested by the petitioner. NHTSA is also 
establishing the reporting and recordkeeping 
requirements necessary for it to enforce the phase- 
in. Finally, NHTSA is adopting a phase-in exclu- 
sion for vehicles manufactured in two or more 
stages and for altered vehicles. 

DATES: The amendments in this final rule are 
effective September 1, 1993. NHTSA notes, how- 
ever, that the amendments to Standard No. 214 
have the effect of providing an additional year's 
leadtime for certain doors and vehicles. 



Background 

On June 14, 1991, NHTSA published in the 
Federal Register (56 FR 27427) a final rule 
extending the quasistatic side door strength 
requirements of Federal Motor Vehicle Safety 
Standard No. 214, Side Impact Protection, to 
trucks, buses and multipurpose passenger vehicles 
(MPV's) with a gross vehicle weight rating of 
10,000 pounds or less. (These vehicles are collec- 
tively referred to as "LTV's.") The agency estab- 
lished an effective date of September 1, 1993 for 
the extended applicability of the requirements, 
thus providing a leadtime of just over two years 
from the time of the final rule. Certain side doors, 
including ones that are more than a specified dis- 
tance away from seats and therefore unlikely to 
have vehicle occupants sitting near them, were 
excluded from the coverage of the standard. 

Standard No. 214's quasi-static requirements, 
which have applied to passenger cars since Janu- 
ary 1, 1973, seek to mitigate occupant injuries in 
side impacts by reducing the extent to which the 
side structure of a vehicle is pushed into the pas- 
senger compartment during a side impact. The 
requirements specify that side doors must resist 
crush forces that are applied against the door's 
outside surface in a laboratory test. The load is 
applied by means of a piston pressing a vertical 
steel cylinder against the middle of the door. 
Since car manufacturers have generally chosen to 
meet the requirements by reinforcing the side 
doors with metal beams, the agency expects that 
LTV manufacturers will generally do the same. 



PART 571: S214-PRE-75 



Petition for Reconsideration 

NHTSA received one petition for reconsider- 
ation of the final rule extending Standard No. 
214's quasi-static side door strength requirements 
to LTV's, from General Motors (GM). The peti- 
tioner requested that, instead of making the 
requirements effective for all LTV's on Septem- 
ber 1, 1993, the agency provide the following 
phase-in: 75 percent of LTV's manufactured in 
the production year beginning September 1, 1993, 
90 percent of LTV's manufactured in the produc- 
tion year beginning September 1. 1994, and 100 
percent of LTV's effective September 1, 1995. 

GM stated that a phase-in of the requirements 
is essential for two reasons. First, that company 
noted that the agency has not yet established the 
test requirements for double cargo doors and for 
doors with no windows. GM stated that until the 
test requirements for double cargo doors and 
doors without windows are known, it cannot 
design the modifications needed to meet the 
requirements for those doors. According to the 
petitioner, the modifications may include struc- 
tural or hardware changes as well as the installa- 
tion of side door beams. GM stated that two years 
is an absolute minimum leadtime, barely allowing 
for validation of the design, and thus leaving 
inadequate time for other considerations such as 
cost and mass optimization. 

GM also argued that because the requirements 
for some types of side doors are not yet com- 
pleted, manufacturers cannot yet modify a vehicle 
to meet the requirements for all available types of 
side doors in one design iteration. According to 
GM, manufacturers generally implement design 
changes on all like models based on the most 
severe test requirements. Thus, if GM designed a 
particular model with sliding doors to meet Stand- 
ard No. 214 and the test requirements for doors 
without windows or for double cargo doors later 
turned out to have the most severe implications 
on product design (e.g., required structural 
changes), GM's first redesign would be obsolete. 
The company indicated that a phase-in would 
help address this concern. 

The second reason cited by GM in support of 
its argument that a phase-in is needed is the pos- 
sible interaction between the requirements of 
Standard No. 214 and other safety standards, 
especially Standard No. 208, Occupant Crash 
Protection. GM argued that such interaction may 



require longer leadtime for some vehicles. (Under 
Standard No. 208, vehicles must meet specified ^^ 
injury criteria, including a head injury criterion |^ 
(HIC), measured on test dummies in frontal bar- 
rier crash tests.) 

According to GM, side door beams installed to 
meet Standard No. 214 can change a vehicle's 
frontal barrier performance enough to necessitate 
retesting to recertify the vehicles to Standard No. 
208 and other standards. The company stated that 
the addition of door beams generally stiffens a 
vehicle's occupant compartment. While this usu- 
ally helps reduce the likelihood of dummy head 
contacts in standard No. 208 testing. GM stated 
that its experience shows that stiffening the occu- 
pant compartment can also increase non-contact 
HICs in Standard No. 208 tests, particularly when 
using the Hybrid III test dummy (one of two 
alternative test dummies specified by the stand- 
ard). In a meeting with NHTSA staff concerning 
its petition, GM provided data from crash tests for 
one model in which the addition of a roof 
reinforcement increased HIC from 930 to 1010, 
and the further addition of door beams raised HIC 
to 1250. 

GM stated that the expected modifications for ^ 
Standard No. 214 will substantially affect the 
performance in Standard No. 208 tests only in a 
minority of LTV models. The company argued, 
however, that some LTV models will likely need 
significant changes to achieve adequate perform- 
ance in frontal barrier crashes because of crash 
pulse changes caused by the installation of side 
door beams and that it will not know which mod- 
els need such changes until it completes the fron- 
tal baiTier tests. GM argued that a phase-in is 
needed to provide the longer leadtime it believes 
is required to make the necessary design changes 
and conduct compliance testing for this group of 
LTV's. 

The petitioner stated that the first year phase- 
in of 75 percent that it recommends would 
include all of a manufacturer's LTV's except per- 
haps one or two van models that have double 
cargo doors or doors without windows for which 
test requirements are not yet defined and/or one 
or two other LTV models that cannot be 
recertified to meet Standard No. 208 by Septem- 
ber 1, 1993 if side door beams are added. GM 
stated that the second year phase-in of 90 percent % 

that it recommends would include all of a manu- 
facturer's LTV's except perhaps one small-vol- 



PART 571; S214-PRE-76 



ume LTV model that cannot yet be recertified to 
meet Standard No. 208 if side door beams are 
added. 

GM also argued that its recommended phase-in 
would allow manufacturers to meet the new 
requirements with designs that are more opti- 
mized for cost and mass, and that are less likely 
to degrade other areas of vehicle performance. 
The company stated that manufacturers may use 
the phase-in to avoid diverting test and design 
resources from other important safety and crash- 
worthiness projects, such as implementing air 
bags in advance of the mandated automatic 
restraint phase-in. Finally, GM stated that it 
believes that its proposed phase-in is reasonable 
and meets the intent of the agency to extend 
Standard No. 214's side door strength require- 
ments to LTV's promptly and practicably. 

While GM was the only petitioner for 
reconsideration, Chrysler submitted a letter 
strongly urging that NHTSA grant 's petition and 
adopt the phase-in schedule recommended by 
GM. Chrysler stated that it shared GM's concern 
that the test requirements for double-opening side 
cargo doors and doors without windows will not 
be available in time for it to meet the require- 
ments by September 1, 1993. That company 
stated that while it does not manufacture any full- 
size vans/wagons with such doors which are suffi- 
ciently close to seats to be covered by the stand- 
ard, it manufactures many such vans with those 
types of doors that are sold to van converters who 
do install seats close to the doors. Chrysler stated 
that it therefore expects to be asked to provide 
vehicles that meet door crush requirements to 
these final stage manufacturers so that they can 
take advantage of "pass-through" certification. 
Also, Ford Motor Company expressed its support 
for a brief phase-in, in a meeting with Department 
officials. 

Summary of Amendments Being Made in 
Response to GM's Petition 

In response to GM's petition, NHTSA is 
amending Standard No. 214 in several respects. 
First, the agency is establishing a brief phase-in 
for the newly-extended requirements. For the 
production year beginning September 1, 1993, 90 
percent of a manufacturer's LTV's will be 
required to meet the new requirements; 100 per- 
cent compliance will be required effective 
September 1, 1994. Second, NHTSA is delaying 



by one year, to September 1, 1994, the effective 
date of the requirements for double opening cargo 
doors and doors with no windows, since the test 
procedure for these doors has not yet been estab- 
lished. The agency is also delaying the effective 
date for certain contoured doors, since it has 
determined that the test procedure for these doors 
also needs clarification. 

Since NHTSA is adopting a phase-in, it is also 
establishing the reporting and recordkeeping 
requirements necessary for the agency to enforce 
the phase-in. Similar requirements have been 
adopted by the agency as an integral part of its 
phase-ins of other major new safety requirements. 
Finally, the agency is adopting a phase-in exclu- 
sion for vehicles manufactured in two or more 
stages and for altered vehicles. 

Response to GM's Petition 

Several commenters on NHTSA's proposal to 
extend Standard No. 214's side door strength 
requirements to LTV's requested a phase-in of the 
requirements. In the preamble to the June 1991 
final rule, the agency addressed the related issues 
of leadtime and the appropriateness of a phase-in 
as follows: 

"After considering [the] comments and other 
information, NHTSA has decided to make the 
new requirements effective on September 1, 
1993. NHTSA has concluded that manufactur- 
ers need this time period to equip all LTV's 
with side door beams as standard equipment 
after the necessary design, tooling, and testing. 
In addition, final-stage manufacturers need this 
much time to decide how to certify compliance 
with the requirements. * * * 

"NHTSA does not believe that additional 
leadtime or a phase-in is necessary. Door beam 
technology has been used with passenger cars 
since 1973. Further, a few LTV's are currently 
manufactured with side door beams. While 
Ford initially asserted that the installation of 
side door beams in one of its models would 
require major design changes. Ford has since 
developed a beam design which can be 
installed in the door of the specific model with- 
out a major design change." 56 FR 27436. 
After considering GM's petition for reconsider- 
ation, however, NHTSA has concluded that GM's 
two primary arguments have merit and warrant 
changes in the standard's effective date. The 
agency's analysis of GM's arguments and a 



PART 571; S214-PRE-77 



discussion of the changes being made in response 
to those arguments follow. 

NHTSA agrees with GM's first main argument 
that the lack of test procedures for double-open- 
ing cargo doors and doors without windows 
makes it impossible for manufacturers to com- 
plete the necessary design modifications for these 
doors. The agency indicated in the June 1991 
final rule that it expected "in the near future" to 
propose amendments to address test procedures 
for these doors. However, the development of the 
proposal took longer than expected, and it was 
not published until January 15. 1992, with a com- 
ment closing date of March 16, 1992. See 57 FR 
1716. Thus, the continuing lack of test procedures 
for these doors has cut much farther into the two- 
year leadtime period than expected. Assuming 
that a final rule is issued this summer or early 
Fall, the remaining leadtime would be little more 
than one year. 

In order to ensure that the "practicability" 
requirements of the National Traffic and Motor 
Vehicle Safety Act are met and that manufactur- 
ers have sufficient leadtime for the necessary 
design, tooling, and testing of double-opening 
cargo doors and doors without windows, NHTSA 
has decided to extend the effective date for these 
doors by one year, to September 1, 1994. Assum- 
ing that the agency publishes a final rule concern- 
ing the test procedures some time this summer or 
early Fall, this will provide manufacturers with 
approximately two years leadtime for these doors. 

NHTSA does not believe that GM's argument 
about its desire to modify all like models based 
on the most severe test requirements justifies 
relief beyond providing additional leadtime for 
the types of doors for which test procedures have 
not yet been established. First, even in the 
absence of the details of the test procedure, the 
agency believes that the performance require- 
ments set forth in Standard No. 214 for double- 
opening cargo doors and doors without windows 
are sufficient for manufacturers to determine 
whether structural or other changes beyond add- 
ing a door beam will be required. Therefore, 
manufacturers should be able to determine 
whether these doors represent the most severe test 
requirement for a particular model and design 
other types of doors for the same model with that 
in mind, thereby avoiding a need for more than 
one design iteration. Second, given the safety 
benefits associated with this ailemaking, the 



agency believes that it would be inappropriate to 
delay application of the standard to types of doors 
for which design changes can easily be made ^^ 
merely to facilitate future compliance for other ^^ 
types of doors. 

As discussed in the January 1992 notice of pro- 
posed rulemaking (NPRM) concerning test proce- 
dures for double-opening cargo doors and doors 
without windows, NHTSA has determined that 
clarification of the test procedure is also needed 
for certain contoured doors. The NPRM therefore 
proposed amendments to clarify the test procedure 
for contoured doors. 

Standard No. 214's test procedure works well 
when a door's lower edge is essentially horizontal 
along its entire length, or only a small portion of 
the door's lower edge deviates from that descrip- 
tion by being contoured upward. Almost all pas- 
senger cars have doors of these types. However, 
as discussed in the January 1992 NPRM, the 
standard's test procedure is not appropriate when 
only a small portion of a door's lower edge is 
horizontal and the edge is contoured significantly 
upwards for a large part of the door. Some LTV's 
have such doors. Since, in the absence of clarify- 
ing amendments concerning test procedures, these 
doors pose similar difficulties concerning compli- ^^ 
ance as those for double-opening cargo doors and 
doors without windows, NHTSA is also extending 
the effective date for these doors to September 1, 
1994. 

After reviewing the infonnation submitted by 
GM in support of its petition, NHTSA is also per- 
suaded that the possible interaction between the 
requirements of Standard No. 214 and other 
safety standards, particularly Standard No. 208, 
may require longer leadtime for a few vehicles. 

As indicated above, NHTSA concluded in the 
June 1991 final rule that manufacturers required 
about two years leadtime for the design, tooling 
and testing necessary to meet the new require- 
ments, and that additional leadtime was not 
needed in light of the time side door beam tech- 
nology has been used for passenger cars. The 
two-year period did not, however, account for the 
possibility that a few vehicles, after being 
redesigned for Standard No. 214, might require 
further redesign to ensure that they continue to 
meet the dynamic test requirements of Standard 
No. 208. ^ 

NHTSA does not consider it likely, for a ^ 

particular LTV, that the addition of side door 



PART 571; S2I4-PRE-78 



beams would increase HIC in Standard No. 208 
testing. The occupant compartments of LTV's are 
generally stiffer than those of passenger cars, and 
any incremental stiffness that may result from the 
addition of side door beams is likely to be 
extremely small. Further, as indicated by GM, the 
stiffening of a vehicle's occupant compartment 
usually reduces the likelihood of dummy head 
contacts in frontal crash tests. For most current 
vehicles, this would be expected to reduce HIC. 
In addition, even if the addition of side door 
beams did slightly raise noncontact HIC, this 
would only affect the compliance of vehicles with 
Standard No. 208 if the vehicles previously only 
marginally complied with the standard. The 
agency believes that the small possibility of a 
particular vehicle's HIC being increased by the 
addition of side door beams is demonstrated by 
the fact that no other manufacturer has presented 
information to the agency concerning the prob- 
lem. Further, GM, in responding to the agency's 
request for data concerning this problem, provided 
data for only one vehicle. 

NHTSA agrees, however, that the test data pre- 
sented by GM demonstrate that the addition of 
side door beams may, for a few vehicles, suffi- 
ciently affect HIC that further redesign will be 
necessary to ensure that the vehicles continue to 
meet Standard No. 208. 

The agency has therefore decided to establish a 
brief phase-in for the new requirements. Accord- 
ingly, for the production year beginning Septem- 
ber 1, 1993, 90 percent of a manufacturer's 
LTV's will be required to meet the new require- 
ments; 100 percent compliance will be required 
effective September 1, 1994. Thus, the agency is 
providing an extra year's leadtime for up to 10 
percent of a manufacturer's production of LTV's. 

NHTSA believes that the phase-in being 
adopted will provide sufficient flexibility to cover 
the possibility that the compliance of a few 
LTV's with Standard No. 208 could be affected 
by the addition of side door beams and therefore 
need further redesign. The agency has carefully 
reviewed the information provided by GM and 
does not believe that the number of vehicles that 
could be affected would exceed 10 percent of that 
company's annual LTV production. Further, given 
the small number of vehicles, if any, that would 
be involved, the agency believes that an addi- 
tional year's leadtime is ample for a manufacturer 
to make any additional changes necessary to 



ensure continuing compliance with Standard No. 
208. Finally, given the fact that the delay in 
effective date affects no more than 10 percent of 
a manufacturer's LTV production for a single 
year and that it appears that not all manufacturers 
would avail themselves of the phase-in, any 
reduction in safety benefits is minimized. 

NHTSA notes that it is not adopting the spe- 
cific phase-in recommended by the petitioner, i.e., 
75 percent of LTV's for the production year 
beginning September 1, 1993, and 90 percent of 
LTV's for the following year. The agency 
believes, for the reasons stated above, that the 
combination of delaying the effective date for 
double-opening cargo doors and doors without 
windows and the one-year phase-in adequately 
addresses the concerns raised by GM's two main 
arguments. 

As indicated above, GM also asserted that its 
recommended phase-in would allow manufactur- 
ers to meet the new requirements with designs 
that are more optimized for cost and mass and 
that are less likely to degrade other areas of 
vehicle performance. That company also asserted 
that manufacturers may use the phase-in to avoid 
diverting test and design resources from other 
important safety and crashworthiness projects, 
such as implementing air bags in advance of the 
mandated automatic restraint phase-in. However, 
GM did not provide any evidence demonstrating 
that additional leadtime, beyond that provided by 
this final rule, is needed for design optimization 
or would result in any safety benefits by facilitat- 
ing design improvements in other areas. In the 
absence of such evidence and given the reduced 
safety benefits that could result from a longer 
phase-in, the agency does not believe that a 
longer phase-in is appropriate. 

In the NPRM proposing to extend the side door 
strength requirements of Standard No. 214 to 
LTV's, the agency requested that any commenters 
supporting a leadtime longer than two years 
address whether such longer leadtime is needed 
for all vehicles or whether the proposed amend- 
ments could be phased in for some vehicles at an 
earlier time. See 54 FR 52832, December 22, 
1989. The agency thus addressed in the NPRM 
the possibility of a phase-in. Several commenters, 
including GM, Ford and the Motor Vehicle 
Manufacturers Association, supported a phase-in. 
Ford requested that the agency adopt in any final 
rule, provisions such as those in Standard No. 208 



PART 571; S214-PRE-79 



for production volumes, carryforward credits, and 
cars produced by more than one manufacturer. 

While NHTSA did not discuss in the NPRM 
the specific requirements that would be associated 
with a phase-in, the agency has addressed that 
issue in three other rulemakings: (1) the establish- 
ment of Standard No. 208 's automatic crash 
protection requirements for cars, (2) the extension 
of those requirements to LTV's, and (3) the 
establishment of Standard No. 214"s dynamic side 
impact protection requirements for cars. In each 
case, for example, reporting and recordkeeping 
requirements have been integral parts of the 
phase-ins. Given that the agency raised the 
possibility of a phase-in in the NPRM and the 
general understanding commenters had concerning 
how the agency implemented phase-ins in other 
rulemakings, NHTSA believes that the establish- 
ment of specific phase-in requirements along the 
lines of those in Standard No. 208 and Standard 
No. 214 (dynamic side impact requirements for 
passenger cars) are within the scope of notice for 
this rulemaking. 

As suggested by Ford in its comment on the 
NPRM, the agency is including provisions similar 
to those in Standard No. 208 for production vol- 
umes and vehicles produced by more than one 
manufacturer. As in the case of the agency's 
phase-in of Standard No. 214's dynamic require- 
ments for passenger cars, NHTSA is not, how- 
ever, including the provisions for carry-forward 
credits. The purpose of the limited phase-in 
adopted in response to GM's petition is to pro- 
vide an additional year's leadtime for up to 10 
percent of a manufacturer's LTV production. 
Carryforward credits are unnecessary to meet this 
purpose. Further, some LTV's already meet the 
requirements of Standard No. 214, and a provi- 
sion permitting manufacturers to count such 
vehicles toward the 90 percent one-year require- 
ment could unnecessarily dilute that requirement, 
resulting in reduced safety benefits. 

NHTSA is also establishing the reporting and 
recordkeeping requirements necessary for the 
agency to enforce the phase-in. The requirements 
are similar to those adopted for Standards No. 
208 and No. 214, although only a single report is 
required since the phase-in is for one year. For a 
further explanation of the agency's rationale for 
the specific requirements, see the preamble to the 
final rule establishing those requirements for the 
phase-in of Standard No. 214's dynamic require- 



ments for passenger cars (56 FR 43768, October 

30, 1990). _ 

As the agency recognized for the phase-in of ^^ 
Standard No. 208 's automatic restraint require- 
ments for LTV's, a phase-in of requirements for 
LTV's has the possibility of creating significant 
problems for many final stage manufacturers and 
alterers. Like other manufacturers, final stage 
manufacturers and alterers must certify that their 
vehicles meet all applicable safety standards. 
Many of these manufacturers are small businesses 
and typically complete or modify vehicles based 
on instructions from the major manufacturers, as 
a basis for certification. 

The potential problems that could be caused by 
applying a phase-in requirement to these manu- 
facturers can be illustrated by considering the 
case of a van converter which purchases vans 
from GM, Ford or Chrysler and then alters them 
for the specialty market. If the one-year 90 per- 
cent phase-in requirement were applied to van 
converters, each van converter would need to 
ensure that 90 percent of the vans it altered com- 
plied with Standard No. 214. However, many van 
converters are very small and only alter a few 
vans each year. If the vehicles a particular van ^ 

converter wanted to alter happened to be ones for ^^ 

which GM, Ford or Chrysler determined that the 
extra year's leadtime permitted by the phase-in 
was needed, it is highly unlikely the van con- 
verter could make the necessary design changes 
to those vehicles to certify that they would meet 
Standard No. 214. 

In light of the potential problems that the 
phase-in could cause for final stage manufacturers 
and alterers, NHTSA is excluding LTV's manu- 
factured in two or more stages and LTV's that are 
altered from Standard No. 214's requirements 
during the phase-in. This is the same approach 
that the agency followed for the phase-in of 
Standard No. 208 's automaUc crash protection 
requirements for LTV's. See 56 FR 12479-80, 
March 26, 1991. Because of this exclusion, this 
rule also permits original manufacturers the 
option to either include or exclude their LTV's 
that are sent to second stage manufacturers and 
alterers, when determining compliance during the 
phase-in for Standard No. 214. 

This final rule does not have any retroactive 
effect. Under section 103(d) of the National Traf- ^ 

fie and Motor Vehicle Safety Act (15 U.S.C. ^ 

1392(d)), whenever a Federal motor vehicle safety 



PART 571; S214-PRE-80 



standard is in effect, a state may not adopt or 
maintain a safety standard applicable to the same 
aspect of performance which is not identical to 
the Federal standard. Section 105 of the Act (15 
U.S.C. 1394) sets forth a procedure for judicial 
review of final rules establishing, amending or 
revoking Federal motor vehicle safety standards. 
That section does not require submission of a 
petition for reconsideration or other administrative 
proceedings before parties may file suit in court. 
In consideration of the foregoing. Parts 57 1 and 
586 of Title 49 of the Code of Federal Regula- 
tions are amended as follows: 

Part 571— [AMENDED] 

1. The authority citation for Part 571 continues 
to read as follows: 

Authority: 15 U.S.C. 1392, 1401. 1403, 1407; 
delegation of authority at 49 CFR 1.50. 

2. In S571.214, S2.1, as added at 56 FR 27437, 
June 14, 1991, effective September 1, 1993, is 
revised to read as follows: 

S2.1. Definitions. 

Double cargo doors means a pair of hinged 
doors with the lock and latch mechanisms located 
where the door lips overlap. 

Walk-in van means a van in which a person can 
enter the occupant compartment in an upright 
position. 

3. In S571.214, S3, as revised at 56 FR 27437, 
June 14, 1991, effective September 1, 1993, is 
amended by revising S3(a) and adding new 
S3(e)(5) through S3(e)(7) to read as follows: 

S3. Requirements, (a)(1) Except as provided 
in section S3(e), each passenger car shall be able 
to meet the requirements of either, at the manufac- 
turer's option, S3.1 or S3.2, when any of its side 
doors that can be used for occupant egress is 
tested according to S4. 

(2) Except as provided in section S3(e), each 
multipurpose passenger vehicle, truck and bus 
manufactured on or after September 1, 1994 shall 
be able to meet the requirements of either, at the 
manufacturer's option, S3.1 or S3. 2, when any of 
its side doors that can be used for occupant egress 
is tested according to S4. 

(3) Except as provided in section S3(e), from 
September 1, 1993 to August 31, 1994, at least 90 
percent of each manufacturer's combined yearly 
production of multipurpose passenger vehicles. 



trucks and buses with a GVWR of 10.000 pounds 
or less, as set forth in S9, shall be able to meet 
the requirements of either, at the manufacturer's 
option, S3.1 or S3. 2, when any of its side doors 
that can be used for occupant egress is tested 
according to S4. 



(e) * * * 

(5) for multipurpose passenger vehicles, trucks, 
and buses manufactured before September 1, 
1994, any double cargo doors. 

(6) for multipurpose passenger vehicles, trucks, 
and buses manufactured before September 1, 
1994, any doors without one or more windows. 

(7) for multipurpose passenger vehicles, trucks, 
and buses manufactured before September 1, 
1994, any doors for which the ratio of the width 
of the lowest portion of the door to the width of 
the door at its widest point is not greater than 0.5. 
The width of the door is measured in a horizontal 
plane and on the outside surface of the door. The 
lowest portion of the door is that portion of the 
lower edge of the door which is lowest to the 
ground and which is essentially horizontal. 



4. In S571.214, S9 through S9.2.3 are added to 
read as follows: 

S9. Phase-in of side door strength require- 
ments for multipurpose passenger vehicles, 
trucks and buses. 

S9.1 Multipurpose passenger vehicles, trucks 
and buses manufactured on or after Septem- 
ber 1, 1993 and before September 1, 1994. 

S9.1.1 The combined number of multipurpose 
passenger vehicles, trucks and buses with a 
GVWR of 10,000 pounds or less complying with 
the requirements of S3(a)(3) shall not be less than 
90 percent of: 

(a) The average annual production of multipur- 
pose passenger vehicles, trucks and buses with a 
GVWR of 10,000 pounds or less manufacmred on 
or after September 1, 1990 and before September 
1, 1993 by each manufacturer, or 

(b) The manufacturer's annual production of 
multipurpose passenger vehicles, trucks and buses 
with a GVWR of 10,000 pounds or less during 
the period specified in S9.1. 



PART 571; S214-PRE-81 



S9.1.2 Walk-in vans, vehicles which do not have 
any side doors that can be used for occupant 
egress, vehicles which exclusively have doors of 
the types specified in S3(e), and vehicles specified 
in S9.2.3 may be excluded from all calculations of 
compliance with S9.1.1. 

S9.2 Multipurpose passenger vehicles, trucks 
and buses produced by more than one manu- 
facturer. 

59.2.1 For the purposes of calculating average 
annual production of multipurpose passenger 
vehicles, trucks and buses with a GVWR of 
10,000 pounds or less for each manufacturer and 
the number of multipurpose passenger vehicles, 
trucks and buses with a GVWR of 10.000 pounds 
or less manufactured by each manufacturer under 
S9.1.1, a vehicle produced by more than one 
manufacturer shall be attributed to a single manu- 
facturer as follows, subject to S9.2.2: 

(a) A vehicle which is imported shall be attrib- 
uted to the importer. 

(b) A vehicle manufactured in the United States 
by more than one manufacturer, one of which 
also markets the vehicle, shall be attributed to the 
manufacturer which markets the vehicle. 

59.2.2 A vehicle produced by more than one 
manufacturer shall be attributed to any one of the 
vehicle's manufacturers specified by an express 
written contract, reported to the National Highway 
Traffic Safety Administration under 49 CFR Part 
586, between the manufacturer so specified and 
the manufacturer to which the vehicle would 
otherwise be attributed under S9.2. 1 . 

59.2.3 Each multipurpose passenger vehicle, truck 
and bus with a GVWR of 10,000 pounds or less 
that is manufactured in two or more stages or that 
is altered (within the meaning of S567.7 of this 
chapter) after having previously been certified in 
accordance with Part 567 of this chapter is not 
subject to the requirements of S3(a)(3). 

Part 586 [AMENDED] 

5. The authority citation for Part 586 continues 
to read as follows: 

Authority: 15 U.S.C. 1392, 1401, 1407; delega- 
tion of authority at 49 CFR Part 1 .50. 

6. Section 586.1 is revised to read as follows: 



5586.1 Scope. 

This part establishes requirements for passenger 
car manufacturers to submit a report, and main- ^ 
tain records related to the report, concerning the ^ 
number of passenger cars manufactured that meet 
the dynamic test procedures and performance 
requirements of Standard No. 214, Side Impact 
Protection (49 CFR 571.214), and it establishes 
requirements for manufacturers of multipurpose 
passenger vehicles, trucks and buses with a gross 
vehicle weight rating (GVWR) of 10,000 pounds 
or less to submit a report, and maintain records 
related to the report, concerning the number of 
such vehicles that meet the side door strength 
requirements of Standard No. 214. 

7. Section 586.2 is revised to read as follows: 

5586.2 Purpose. 

The purpose of the reporting requirements is to 
aid the National Highway Traffic Safety Adminis- 
tration in determining whether a passenger car 
manufacturer has complied with the requirements 
of Standard No. 214, Side Impact Protection (49 
CFR 571.214) concerning dynamic test proce- 
dures and performance requirements concerning 
side impact protection, and whether a manufac- 
turer of multipurpose passenger vehicles, trucks ^ 
and buses with a GVWR of 10,000 pounds or less " 
has complied with the side door strength require- 
ments of Standard No. 214. 

8. Section 586.3 is revised to read as follows: 

5586.3 Applicability. 

This part applies to manufacturers of passenger 
cars and to manufacturers of multipurpose pas- 
senger vehicles, trucks and buses with a GVWR 
of 10,000 pounds or less. However, this part does 
not apply to any manufacturers of multipurpose 
passenger vehicles, trucks and buses whose 
production consists exclusively of walk-in vans, 
vehicles which do not have any side doors that 
can be used for occupant egress, vehicles which 
exclusively have doors of the types specified in 
S3(e) of 49 CFR 571.214, vehicles manufactured 
in two or more stages, and vehicles that are 
altered after previously having been certified in 
accordance with Part 567 of this chapter. 

9. Section 586.4 is amended by revising para- 
graph (b) to read as follows: 

5586.4 Definitions. ▲ 



PART 571; S214-PRE-82 



(b) Bus, gross vehicle weight rating or GVWR, 
multipurpose passenger vehicle, passenger car, 
and truck are used as defined in S571.3 of this 
chapter. 



10. Section 586.5 is amended by revising the 
heading to read as follows: 

S586.5 Reporting requirements — manufactur- 
ers of passenger cars. 



11. Section 586.6 is amended by revising the 
heading to read as follows: 

S586.6 Records— passenger cars. 



12. Section 586.7 is redesignated as section 
586.9 and revised to read as follows: 

S586.9 Petition to extend period to file report. 

A petition for extension of the time to submit 
a report must be received not later than 15 days 
before expiration of the time stated in § 586.5(a) 
or §586.7 (a). The petition must be submitted to: 
Administrator. National Highway Traffic Safety 
Administration, 400 Seventh Street, S.W., 
Washington, D.C. 20590. The filing of a petition 
does not automatically extend the time for filing 
a report. A petition will be granted only if the 
petitioner shows good cause for the extension and 
if the extension is consistent with the public 
interest. 

13. Sections 586.7 and 586.8 are added to read 
as follows: 

S586.7 Reporting requirements— manufactur- 
ers of trucl<s, buses and multipurpose pas- 
senger vehicles. 

(a) General reporting requirements. Within 60 
days after the end of the production year ending 
August 31, 1994, each manufacturer shall submit 
a report to the National Highway Traffic Safety 
Administration concerning its compliance with the 
requirements of S3(a) of Standard No. 214 for its 



tmcks, buses and multipurpose passenger vehicles 
produced in that year. Each report shall — 

(1) Identify the manufacturer; 

(2) State the full name, title, and address of the 
official responsible for preparing the report; 

(3) Contain a statement regarding whether or 
not the manufacturer complied with S3(a)(3) of 
Standard No. 214 and the basis for that statement; 

(4) Provide the information specified in 
§ 586.7(b); 

(5) Be written in the English language; and 

(6) Be submitted to: Administrator, National 
Highway Traffic Safety Administration, 400 Sev- 
enth Street, SW., Washington, DC 20590. 

(b) Report content — (1) Basis for phase-in 
production goals. Each manufacturer shall provide 
the number of trucks, buses and multipurpose pas- 
senger vehicles with a GVWR of 10,000 pounds 
or less manufactured for sale in the United States 
for each of the three previous production years, 
or, at the manufacturer's option, for the current 
production year. A new manufacturer that has not 
previously manufactured trucks, buses and multi- 
purpose passenger vehicles with a GVWR of 
10.000 pounds or less for sale in the United 
States must report the number of such vehicles 
manufactured during the current production year. 

(2) Production. Each manufacturer shall report 
the number of multipurpose passenger vehicles, 
trucks and buses with a GVWR of 10,000 pounds 
or less that meet the side door strength require- 
ments (S3.1 or S3.2) of Standard No. 214. 

(3) Vehicles produced hy more than one manu- 
facturer. Each manufacturer whose reporting of 
information is affected by one or more of the 
express written contracts permitted by 59.2.2 of 
Standard No. 214 shall: 

(i) Report the existence of each contract, 
including the names of all parties to the contract, 
and explain how the contract affects the report 
being submitted. 

(ii) Report the actual number of vehicles cov- 
ered by each contract. 



PART 571; S214-PRE-83 



S586.8 Records— multipurpose passenger Issued on: July 7 1992. 

vehicles, trucks and buses. Frederick H. Grubbe, 

Each manufacturer shall maintain records of the Deputy Administrator ^ 

Vehicle Identification Number for each multipur- 57 F R 10917 ^^ 

pose passenger vehicle, truck and bus for which . . ^, iqaj^ 
information is reported under § 586.7(b)(2) until 
December 31, 1996. 



^ 



PART 571; S214-PRE- 



PREAMBLE TO AN AMENDMENT TO 
FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 
Side Impact Protection 

(Docket No. 88-06, Notice 17) 
RIN 2127-AE05 



214 



ACTION: Final rule; corrections. 

SUMMARY: On September 17, 1991, NHTSA 
published in the Federal Register a final rule 
which corrected minor errors in the agency's 
October 1990 final rules concerning dynamic side 
impact requirements for passenger cars. The final 
rule also established an effective date for side 
impact phase-in reporting requirements. Today's 
final rule corrects two errors that were made in the 
September 17, 1991 final rule. First, Figure 2 of 
Standard No. 214, Side Impact Protection, which 
provides a schematic of the moving deformable 
barrier used in the dynamic side impact test, is 
corrected to include certain specifications that 
were inadvertently omitted. Second, the final rule 
establishes an effective date for certain of the side 
impact phase-in reporting requirements that were 
inadvertently not covered by the September 1991 
final rule. 

DATES: Effective Date: The amendments in this 
document and § 586.5, published at 55 FR 45770 
on October 30, 1990, are effective June 22, 1992. 

SUPPLEMENTARY INFORMATION: On October 
30, 1990, NHTSA published in the Federal Reg- 
ister (55 FR 45722) a final rule adding dynamic 
test procedures and performance requirements to 
Standard No. 214, Side Impact Protection. The 
dynamic test requirements of Standard No. 214 
are phased in over a three-year period, beginning 
on September 1, 1993. At the same time, NHTSA 
also published final rules: (1) establishing the 
specifications for the side impact dummy to be 
used in the dynamic crash test (55 FR 45757), (2) 
establishing the attributes of the moving deform- 
able barrier (MDB) to be used in the dynamic 
crash test (55 FR 45770), and (3) establishing the 
reporting and recordkeeping requirements nec- 
essary for NHTSA to enforce the phase-in of the 
new dynamic requirements. 



On September 17, 1991, NHTSA published in 
the Federal Register (56 FR 47007) a final rule 
which corrected minor errors in the October 1990 
final rules. The final rule also amended the regu- 
lation establishing reporting and recordkeeping 
requirements, 49 CFR part 586, Side Impact 
Phase-In Reporting Requirements, to establish an 
effective date for the regulation's information 
collection requirements and to add the Office of 
Management and Budget (OMB) approval number 
assigned under the Paperwork Reduction Act. 

Ford submitted a petition for reconsideration of 
the September 17, 1991 final rule, expressing 
concern that in revising the schematic of the 
MDB used in the dynamic side impact test (Fig- 
ure 2 of Standard No. 214), NHTSA omitted 
specifications for face plate thickness, material 
strength, and aluminum alloy that were included 
in the earlier version of the schematic. That com- 
pany stated that if the omission of the specifica- 
tions was inadvertent, its letter should be consid- 
ered a request for correcting the specifications 
promptly so that the existing ambiguity is elimi- 
nated. 

In a letter dated December 17, 1991, NHTSA 
advised Ford that the omission of the specifica- 
tions in the schematic of the MDB was inadvert- 
ent and that the agency planned to publish a 
correction notice. Today's final rule corrects Fig- 
ure 2 of Standard No. 214 by adding the speci- 
fications that were inadvertently omitted in the 
September 17, 1991 final rule. 

NHTSA is also setting an effective date for 
§ 586 of part 586. That section was inadvertently 
not made effective in the September 1991 final 
rule. In addition, in order to make part 586 
consistent with the rest of NHTSA' s regulations, 
the agency is removing the OMB control number 
from §586.6. It is NHTSA's standard practice to 
publish the OMB control numbers for all of its 
regulations in a single place, 49 CFR part 509, 



PART 571; S214-PRE-85 



0MB Control Numbers for Information Collection 
Requirements. 

Today's amendments are effective 30 days after 
publication of this document in the Federal Reg- 
ister. The amendments are merely technical 
corrections of the final rule that was published on 
September 17, 1991, which itself made technical 
corrections of final rules published on October 30, 
1990. Today's amendments do not impose any 
new substantive requirements. Therefore, NHTSA 
finds for good cause that notice and comment on 
these amendments are unnecessary. Because of 
the non-substantive nature of the amendments, 
NHTSA also finds for good cause that making the 
rule 30 days after publication is in the public 
interest. 

In consideration of the foregoing, 49 CFR parts 
571 and 586 are amended as follows: 



Figure 2 of §571.214 is revised as follows: 

Part 586— [Amended] |r 

3. The authority section for part 586 continues ^* 
to read as follows: 

Authority: 15 U.S.C. 1392, 1401, 1407; delega- 
tion of authority at 49 CFR 1.50. 

§586.6 [Amended] 

4. Section 586.6 is amended by removing the 
parenthetical at the end of the section. 

Issued on May 14, 1992. 

Jerry Ralph Curry, 
Administrator. 

57 F.R. 21613 
May 21, 1992 



Part 571— [Amended] 

1. The authority section for part 571 continues 
to read as follows: 



PART 5 71; S214-PRE-86 



74" 



143" 
102" 







/ 




■BARRIER 
FACE 



TOP 

VIP// 



RIGHT 
SIDE 
VIEW 



1 -Piece Alum. Honey- 
comb Block - - 45 psi 
± 2.5 psi crush strength -, 

r 0.032" Alum. Back / 
Plate. 26 ksi 5052- / 



NHTSA VEHICLE SIMULATOR 

Alum. Honeycomb Bumper, 245 psi ± 15 psi crush strength 
0.032" Alum. Face. 26 ksi 5052-H34 
- A 66" 




NHTSA BARRIER FACE 
0.125" Alum. Faces, 50 ksi 2024-T3 



SECTION A-A 

Figure 2 — NHTSA Side Impactor — Moving Deformable Barrier 



PART 571; S214-PRE-87 



MOTOR VEHICLE SAFETY STANDARD NO. 214 

Side Impact Protection 
(Docket No. 2-6; Notice No. 3) 



51 Purpose and scope. 

(a) Scope. This standard specifies performance 
requirements for protection of occupants in side 
impact crashes. 

(b) Purpose. The purpose of this standard is to 
reduce the risk of serious and fatal injury to occu- 
pants of passenger cars in side impact crashes by 
specifying vehicle crashworthiness requirements 
in terms of accelerations measured on 
anthropomorphic dummies in test crashes, by 
specifying strength requirements for side doors, 
and by other means. 

52 Applicability. This standard applies to pas- 
senger cars. Effective September 1, 1993, sections 
S3(a), S3(e), S3.1 through S3.2.3, and S4 of the 
standard apply to multipurpose passenger vehicles, 
trucks, and buses with a GVWR of 10,000 pounds 
or less, except for walk-in vans. 

S2.1 Definitions. 

Walk-in van means a van in which a person can 
enter the occupant compartment in an upright 
position. 

Wouble cargo doors means a pair of hinged 
doors with the lock and mechanisms located 
where the door lips overlap. (57 F.R. 30917— July 
13, 1992. Effective: September 1, 1993.)] 

53 Requirements. (a)[(l)] Except as provided 
in section S3(e), each [passenger car] shall be 
able to meet the requirements of either, at the 
manufacturer's option, S3.1 or S3. 2, when any of 
its side doors that can be used for occupant egress 
are tested according to S4. 

[(2) Except as provided in section S3(e), 
each multipurpose passenger vehicle, truck and 
bus manufactured on or after September 1, 
1994, shall be able to meet the requirements of 
either, at the manufacturer's option, S3.1 or 
S3.2, when any of its side doors that can be 
used for occupant egress is tested according to 
S4. 



[(3) Except as provided in section S3(e), 
from September 1, 1993 to August 31, 1994, at 
least 90 percent of each manufacturer's com- 
bined yearly production of multipurpose pas- 
senger vehicles, trucks and buses with a 
GVWR of 10,000 pounds or less, as set forth 
in S9, shall be able to meet the requirements of 
either, at the manufacturer's option, S3.1 or 
S3.2, when any of its side doors that can be 
used for occupant egress is tested according to 
S4. (57 F.R. 30917— July 13, 1992. Effective: 
September 1, 1993.)] 

(b) When tested under the conditions of S6, 
each passenger car manufactured on or after 
September 1, 1996, shall meet the requirements of 
S5.1 S5.2, and S5.3 in a 33.5 miles per hour 
impact in which the car is struck on either side 
by a moving deformable barrier. Part 572, Sub- 
part F test dummies are placed in the front and 
rear outboard seating positions on the struck side 
of the car. However, the rear seat requirements do 
not apply to passenger cars with a wheelbase 
greater than 130 inches, or to passenger cars 
which have rear seating areas that are so small 
that the Part 572, Subpart F dummies cannot be 
accommodated according to the positioning proce- 
dure specified in S7. 

(c) Except as provided in paragraph (d) of this 
section, from September 1, 1993 to August 31, 
1996, a specified percentage of each manufactur- 
er's yearly passenger car production, as set forth 
in S8, shall, when tested under the conditions of 
S6, meet the requirements of S5.1, S5.2, and S5.3 
in a 33.5 miles per hour impact in which the car 
is struck on either side by a moving deformable 
barrier. Part 572, Subpart F test dummies are 
placed in the front and rear outboard seating posi- 
tions on the struck side of the car. However, the 
rear seat requirements do not apply to passenger 
cars with a wheelbase greater than 130 inches, or 
to passenger cars which have rear seating areas 
that are so small that the Part 572, Subpart F 
dummies cannot be accommodated according to 
the positioning procedure specified in S7. 



PART 571; 214-1 



(Rev. 7/13/92) 



(d) A manufacturer may, at its option, comply 
with the requirements of this paragraph instead of 
paragraph (c) of this section. When tested under 
the conditions of S6, each passenger car manufac- 
tured from September 1, 1994 to August 31, 
1996, shall meet the requirements of S5.1, S5.2, 
and S5.3 in a 33.5 miles per hour impact in which 
the car is struck on either side by a moving 
deformable barrier. Part 572, Subpart F test dum- 
mies are placed in the front and rear outboard 
seating positions on the struck side of the car. 
However, the rear seat requirements do not apply 
to passenger cars with a wheelbase greater than 
130 inches, or to passenger cars which have rear 
seating areas that are so small that the Part 572, 
Subpart F dummies cannot be accommodated 
according to the positioning procedure specified 
inS7. 

(e) A vehicle need not meet the requirements 
of sections S3.1 or S3. 2 for — 

(1) any side door located so that no point on 
a ten-inch horizontal longitudial line passing 
through and bisected by the H-point of a mani- 
kin placed in any seat, with the seat adjusted 
to any position and the seat back adjusted as 
specified in section S6.4, falls within the trans- 
verse, horizontal projection of the door's open- 
ing; 

(2) any side door located so that no point on 
a ten-inch horizontal longitudinal line passing 
through and bisected by the H-point of a mani- 
kin placed in any seat recommended by the 
manufacturer for installation in a location for 
which seat anchorage hardware is provided, 
with the seat adjusted to any position and the 
seat back adjusted as specified in section S6.4, 
falls within the transverse, horizontal projection 
of the door's opening; 

(3) any side door located so that a portion of 
a seat, with the seat adjusted to any position 
and the seat back adjusted as specified in sec- 
tion S6.4, falls within the transverse, horizontal 
protection of the door's opening, but a longitu- 
dinal vertical plane tangent to the outboard side 
of the seat cushion is more than 10 inches from 
the innermost point on the inside surface of the 
door at a height between the H-point and 
shoulder reference point (as shown in Figure 1 
of Federal Motor Vehicle Safety Standard No. 
210) and longitudinally between the front edge 
of the cushion with the seat adjusted to its 
forwardmost position and the rear edge of the 



cushion with the seat adjusted to its rearmost 
position; or 

(4) any side door that is designed to be eas- ^L 
ily attached to or removed (e.g., using simple 
hand tools such as pliers and/or a screw driver) 
from a motor vehicle manufactured for oper- 
ation without doors. 

[(5) For multipurpose passenger vehicles, 
trucks, and buses manufactured before Septem- 
ber 1, 1994, any double cargo doors. 

(6) For multipurpose passenger vehicles, 
trucks, and buses manufactured before Septem- 
ber 1, 1994, any doors without one or more 
windows. 

(7) For multipurpose passenger vehicles, 
trucks, and buses manufactured before Septem- 
ber 1, 1994, any doors for which the ratio of 
the width of the lowest portion of the door to 
the width of the door at its widest point is not 
greater than 0.5. The width of the door is 
measured in a horizontal plane and on the out- 
side surface of the door. The lowest portion of 
the door is that portion of the lower edge of the 
door which is lowest to the ground and which 
is essentially horizontal. (57 F.R. 30917— July 

13, 1992. Effective: September 1, 1993.)] % 

53.1 With any seats that may affect load upon or 
deflection of the side of the vehicle removed from 
the vehicle, each vehicle must be able to meet the 
requirements of S3. 1.1 through S3. 1.3. 

53.1.1 Initial Crush Resistance. The initial 
crush resistance shall be not less than 2,250 
pounds. 

53.1.2 Intermediate Crush Resistance. The 

intermediate crush resistance shall not be less than 
3,500 pounds. 

53.1.3 Peak crush resistance. The peak crush 
resistance shall not be less than two times the curb 
weight of the vehicle or 7,000 pounds, whichever 
is less. 

53.2 With seats installed in the vehicle, and 
located in any horizontal or vertical position to 
which they can be adjusted and at any seat back 
angle to which they can be adjusted, each vehicle A 
must be able to meet the requirements of S3.2.1 ^ 
through S3. 2.3. 



(Rev. 7/13/92) 



PART 571; 214-2 



53.2.1 Initial crush resistance. The initial crush 
resistance shall not be less than 2,250 pounds. 

53.2.2 Intermediate crush resistance. The 

intermediate crush resistance shall not be less than 
4,375 pounds. 

53.2.3 Peak crush resistance. The peak crush 
resistance shall not be less than three and one half 
times the curb weight of the vehicle or 12,000 
pounds, whichever is less. 

S4 Test procedures. The following procedures 
apply to determining compliance with section S3: 
(a) Place side windows in their uppermost posi- 
tion and all doors in locked position. Place the sill 
of the side of the vehicle opposite to the side 



being tested against a rigid unyielding vertical 
surface. Fix the vehicle rigidly in position by 
means of tiedown attachments located at or for- 
ward of the front wheel centerline and at or rear- 
ward of the rear wheel centerline. 

(b) Prepare a loading device consisting of a 
rigid steel cylinder or semi-cylinder 12 inches in 
diameter with an edge radius of one-half inch. 
The length of the loading device shall be such 
that the top surface of the loading device is at 
least one-half inch above the bottom edge of the 
door window opening but not of a length that will 
cause contact with any structure above the bottom 
edge of the door window opening during the test. 

(c) Locate the loading device as shown in Fig- 
ure 1 (side view) of this section so that — 

(1) Its longitudinal axis is vertical; 



CENTERLINE OF VEHICLE 




12 INCH DIAM 



PLAN VIEW 



HORIZONTAL LINE 
5 INCHES ABOVE THE 
LOWEST POINT OF 
THE DOOR 

1/2 IN. R. 



STRUCTURES ABOVE THE 
BOTTOM EDGE OF THE DOOR 
.WINDOW OPENING 






- BOTTOM EDGE 
OF DOOR WINDOW 
OPENING 



MID POINT OF LINE 
LOWEST POINT OF THE DOOR 

SIDE VIEW 
Figure 1 — Loading Device Location and Application to the Door 



PART 571; 214-3 



(2) Its longitudinal axis is laterally opposite 
the midpoint of a horizontal line drawn across 
the outer surface of the door 5 inches above the 
lowest point of the door; 

(3) Its bottom surface is in the same hori- 
zontal plane as the horizontal line described in 
subdivision (2) of this subparagraph; and 

(4) The cylindrical face of the device is in 
contact with the outer surface of the door. 

(d) Using the loading device, apply a load to 
the outer surface of the door in an inboard direc- 
tion normal to a vertical plane along the vehicle's 
longitudinal centerline. Apply the load continu- 
ously such that the loading device travel rate does 
not exceed one-half inch per second until the 
loading device travels 18 inches. Guide the load- 
ing device to prevent it from being rotated or dis- 
placed from its direction of travel. The test must 
be completed within 120 seconds. 

(e) Record applied load versus displacement of 
the loading device, either continuously or in 
increments of not more than 1 inch or 200 pounds 
for the entire crush distance of 18 inches. 

(f) Determine the initial crush resistance, inter- 
mediate crush resistance, and peak crush resist- 
ance as follows — 

(1) From the results recorded in subpara- 
graph (e) of this paragraph, plot a curve of load 
versus displacement and obtain the integral of 
the applied load with respect to the crush dis- 
tances specified in subdivisions (2) and (3) of 
this paragraph. These quantities, expressed in 
inchpounds and divided by the specified crush 
distances, represent the average forces in 
pounds required to deflect the door those dis- 
tances. 

(2) The initial crush resistance is the average 
force required to deform the door over the ini- 
tial 6 inches of crush. 

(3) The intermediate crush resistance is the 
average force required to deform the door over 
the initial 12 inches of crush. 

(4) The peak crush resistance is the largest 
force recorded over the entire 18-inch crush 
distance. 

S5 Dynamic performance requirements. 

S5.1 Thorax. The Thoracic Trauma Index 
(TTI(d)) shall not exceed 85 g for passenger cars 
with four side doors, and shall not exceed 90 g for 
passenger cars with two side doors, when cal- 



culated in accordance with the following 
formula — 

'rn(d)=V2 (Gr+Gls) 

The term "Gr" is the greater of the peak accelerations 
of either the upper or lower rib, expressed in g's and 
the term "Gls" is the lower spine (T12) peak accel- 
eration, expressed in g's. The peak acceleration values 
are obtained in accordance with the procedure speci- 
fied in S56. 13.5. 



55.2 Pelvis. The peak lateral acceleration of the 
pelvis, as measured in accordance with S6.13.5, 
shall not exceed 130 g's. 

55.3 Door opening. 

55.3.1 Any side door, which is struck by the mov- 
ing deformable barrier, shall not separate totally 
from the car. 

55.3.2 Any door (including a rear hatchback or 
tailgate), which is not struck by the moving 
deformable barrier, shall meet the following 
requirements — 

55.3.2.1 The door shall not disengage from the 
latched position; ^ 

55.3.2.2 The latch shall not separate from the 
striker, and the hinge components shall not sepa- 
rate from each other or from their attachment to 
the vehicle; and 

55.3.2.3 Neither the latch nor the hinge systems 
of the door shall pull out of their anchorages. 

S6 Test conditions. 

S6.1 Test weight. Each passenger car is loaded 
to its unloaded vehicle weight, plus its rated cargo 
and luggage capacity, secured in the luggage area, 
plus the weight of the necessary anthropomorphic 
test dummies. Any added test equipment is located 
away from impact areas in secure places in the 
vehicle. The car's fuel system is filled in accord- 
ance with the following procedure: With the test 
vehicle on a level surface, pump the fuel from the 
vehicle's fuel tank and then operate the engine 
until it stops. Then, add Stoddard solvent to the 
test vehicle's fuel tank in an amount which is 
equal to not less than 92 percent and not more 
than 94 percent of the fuel tank's usable capacity 
stated by the vehicle's manufacturer. In addition, ^ 
add the amount of Stoddard solvent needed to fill 



(Rev. 5/21/92) 



PART 571; 214-4 



the entire fiiel system from the fuel tank through 
the engine's induction system. 

)) S6.2 Vehicle test attitude. Determine the dis- 
tance between a level surface and a standard ref- 
erence point on the test vehicle's body, directly 
above each wheel opening, when the vehicle is in 
its "as delivered" condition. The "as delivered" 
condition is the vehicle as received at the test site, 
filled to 100 percent of all fluid capacities and 
with all tires inflated to the manufacturer's speci- 
fications listed on the vehicle's tire placard. Deter- 
mine the distance between the same level surface 
and the same standard reference points in the 
vehicle's "fully loaded condition." The "fully 
loaded condition" is the test vehicle loaded in 
accordance with S6.1. The load placed in the 
cargo area is centered over the longitudinal center- 
line of the vehicle. The pretest vehicle attitude is 
equal to either the as delivered or fully loaded atti- 
tude or between the as delivered attitude and the 
fully loaded attitude. 

56.3 Adjustable seats. Adjustable seats are 
placed in the adjustment position midway between 
the forwardmost and rearmost positions, and if 

V, separately adjustable in a vertical direction, are at 

' the lowest position. If an adjustment position does 

not exist midway between the forwardmost and 

rearmost positions, the closest adjustment position 

to the rear of the midpoint is used. 

56.4 Adjustable seat back placement. Place 
adjustable seat backs in the manufacturer's nomi- 
nal design riding position in the manner specified 
by the manufacturer. If the position is not speci- 
fied, set the seat back at the first detent rearward 
of 250 from the vertical. Place each adjustable 
head restraint in its highest adjustment position. 
Position adjustable lumbar supports so that they 
are set in their released, i.e. full back, position. 

56.5 Adjustable steering wheels. Adjustable 
steering controls are adjusted so that the steering 
wheel hub is at the geometric center of the locus 
it describes when it is moved through its full 
range of driving positions. 

56.6 Windows. Movable vehicle windows and 
vents are placed in the fully closed position on the 
struckside of the vehicle. 



56.7 Convertible tops. Convertibles and 
openbody type vehicles have the top, if any, in 
place in the closed passenger compartment 
configuration. 

56.8 Doors. Doors, including any rear hatchback 
or tailgate, are fully closed and latched but not 
locked. 

56.9 Transmission and brake engagement. 

For a vehicle equipped with a manual trans- 
mission, the transmission is placed in second gear. 
For a vehicle equipped with an automatic trans- 
mission, the transmission is placed in neutral. For 
all vehicles, the parking brake is engaged. 

56.10 Moving deformabie barrier. The moving 
deformable barrier conforms to the dimensions 
shown in Figure 2 and specified in Part 587. 

56.11 Impact reference line. For vehicles with 
a wheelbase of 114 inches or less, on the side of 
the vehicle that will be struck by the moving 
deformable barrier, place a vertical reference line 
which is 37 inches forward of the center of the 
vehicle's wheelbase. For vehicles with a wheel- 
base greater than 1 14 inches, on the side of the 
vehicle that will be struck by the moving deform- 
able barrier, place a vertical reference line which 
is 20 inches rearward of the centerline of the 
vehicle's front axle. 

56.12 Impact configuration. The test vehicle 
(vehicle A in Figure 3) is stationary. The line of 
forward motion of the moving deformable barrier 
(vehicle B in Figure 3) forms an angle of 63 
degrees with the centerline of the test vehicle. The 
longitudinal centerline of the moving deformable 
barrier is perpendicular to the longitudinal center- 
line of the test vehicle when the barrier strikes the 
test vehicle. In a test in which the test vehicle is 
to be struck on its left (right) side: all wheels of 
the moving deformable barrier are positioned at an 
angle of 27 ± 1 degrees to the right (left) of the 
centeriine of the moving deformable barrier; and 
the left (right) forward edge of the moving 
deformable barrier is aligned so that a longitudinal 
plane tangent to that side passes through the 
impact reference Hne within a tolerance of ±2 
inches when the barrier strikes the test vehicle. 



PART 571; 214-5 



74" 



49.25" 



143" 
102" 



pfoon^ 






°7 

nB / 



/ 



BARRIER 
FACE 




INSTRUMENTATION - 
BALU\ST AREA 



BALLAST AREA 



1 -Piece Alum. Honey- 
comb Block - - 45 psi 
± 2.5 psi caish strength - 

r 0.032" Alum. Back 
Plate. 26 ksi 5052- 
H34 



TOP 
VIEW 



RIGHT 
SIDE 
VIEW 



NHTSA VEHICLE SIMULATOR 

Alum. Honeycomb Bumper, 245 psi ± 15 psi coish strength 
0.032" Alum. Face, 26 ksi 5052-H34 
r*- A 66" 





NHTSA BARRIER FACE 
0.125" Alum. Faces, 50 ksi 2024-T3 



SECTION A-A 

Figure 2— NHTSA Side Impactor-Moving Deformable Barrier 



(Rev. 10/30/90) 



PART 571; 214-6 



Vehicle A 



i^ 




Impact Point 



Direction of ,yA 
Travel @ ^^^^' 
33.5 mph 



Vehicle B 



Figure 3 — Test Configuration 



PART 571; 214-7 



(Rev. 10/30/90) 



S6.13 Anthropomorphic test dummies. 



S6.1 3.5.4.2 Stopband frequency 189 Hz. 



56.13.1 The anthropomorphic test dummies used 
for evaluation of a vehicle's side impact protection 
conform to the requirements of Subpart F of Part 
572 of this Chapter. In a test in which the test 
vehicle is to be struck on its left side, eacli 
dummy is to be configured and instrumented to be 
struck on its left side, in accordance with Subpart 
F of Part 572. In a test in which the test vehicle 
is to be struck on its right side, each dummy is to 
be configured and instrumented to be struck on its 
right side, in accordance with Subpart F of Part 
572. 

56.13.2 Each Part 572, Subpart F test dummy 
specified is clothed in formfitting cotton stretch 
garments with short sleeves and midcalf length 
pants. Each foot of the test dummy is equipped 
with a size llEEE shoe which meets the configu- 
ration size, sole, and heel thickness specifications 
of MIL-S-13192 (1976) and weighs 1.25±0.2 
pounds. 

56.13.3 Limb joints are set at between 1 and 2 
g's. Leg joints are adjusted with the torso in the 
supine position. 

56.13.4 The stabilized temperature of the test 
dummy at the time of the side impact test shall be 
at any temperature between 66 degrees F and 78 
degrees F. 

56.13.5 The acceleration data from the 
accelerometers mounted on the ribs, spine and pel- 
vis of the test dummy are processed with the 
FIR 100 software specified in 49 CFR Part 572. 
The data are processed in the following manner — 

56.1 3.5.1 Filter the data with a 300 Hz, SAE 
Class 180 filter; 

56.1 3.5.2 Subsample the data to a 1600 Hz sam- 
pling rate; 

56.1 3.5.3 Remove the bias from subsampled data; 
and 

56.1 3.5.4 Filter the data with the FIR 100 software 
specified in 49 CFR Part 572, which has the fol- 
lowing characteristics — 

86.13,5.4.1 Passband frequency 100 Hz. 



56.1 3.5.4.3 Stopband gain 50 db. ^ 

56.1 3.5.4.4 Passband ripple 0.0225 db. 

S7 Positioning procedure for the Part 572 
Subpart F Test Dummy. Position a correctly 
configured test dummy, conforming to Subpart F 
of Part 2 of this Chapter, in the front outboard 
seating position on the side of the test vehicle to 
be struck by the moving deformable barrier and 
position another conforming test dummy in the 
rear outboard position on the same side of the 
vehicle, as specified in S7.1 through S7,4. Each 
test dummy is restrained using all available belt 
systems in all seating positions where such belt 
restraints are provided. In addition, any folding 
armrest is retracted. 

S7.1 Torso. 

57.1.1 For a test dummy in the driver posi- 
tion. 

(a) For a bench seat. The upper torso of the 
test dummy rests against the seat back. The 
midsagittal plane of the test dummy is vertical ^ 
and parallel to the vehicle's longitudinal center- m 
line, and passes through the center of the steering 
wheel. 

(b) For a bucket seat. The upper torso of the 
test dummy rests against the seat back. The 
midsagittal plane of the test dummy is vertical 
and parallel to the vehicle's longitudinal center- 
line, and coincides with the longitudinal centerline 
of the bucket seat. 

57.1.2 For a test dummy in the front outboard 
passenger position. 

(a) For a bench seat. The upper torso of the 
test dummy rests against the seat back. The 
midsagittal plane of the test dummy is vertical 
and parallel to the vehicle's longitudinal center- 
line, and the same distance from the vehicle's 
longitudinal centerline as would be the midsagittal 
plane of a test dummy positioned in the driver 
position under S7.1.1. 

(b) For a bucket seat. The upper torso of the 
test dummy rests against the seat back. The 
midsagittal plane of the test dummy is vertical 

and parallel to the vehicle's longitudinal center- ^ 
line, and coincides with the longitudinal centerline ^ 
of the bucket seat. 



(Rev/ 6/22/92) 



PART 571; 214-8 



S7.1.3 For a test dummy in either of the rear 
outboard passenger positions. 

(a) For a bench seat. The upper torso of the 
test dummy rests against the seat back. The 
midsagittal plane of the test dummy is vertical 
and parallel to the vehicle's longitudinal center- 
line, and, if possible, the same distance from the 
vehicle's longitudinal centerline as the midsagittal 
plane of a test dummy positioned m the driver 
position under S7.1.1. If it is not possible to posi- 
tion the test dummy so that its midsagittal plane 
is parallel to the vehicle longitudinal centerline 
and is at this distance from the vehicle's 
longtitudinal centerline, the test dummy is posi- 
tioned so that some portion of the test dummy 
just touches, at or above the seat level, the side 
surface of the vehicle, such as the upper quarter 
panel, an armrest, or any interior trim (i.e., either 
the broad trim panel surface or a smaller, local- 
ized trim feature). 

(b) For a bucket or contoured seat. The upper 
torso of the test dunmny rests against the seat 
back. The midsagittal plane of the test dummy is 
vertical and parallel to the vehicle's longitudinal 
centerline, and coincides with the longitudinal 
centerline of the bucket or contoured seat. 

S7.2 Pelvis. 

57.2.1 H-Polnt. The H-points of each test 
dummy coincide within V2 inch in the vertical 
dimension and V2 inch in the horizontal dimension 
of a point V4 inch below the position of the H- 
point determined by using the equipment for the 
50th percentile and procedures specified in SAE 
J826 (Apr. 80), except that Table 1 of the SAE 
J826 is not applicable. The length of the lower leg 
and thigh segments of the H-point machine are 
adjusted to 16.3 and 15.8 inches, respectively. 

57.2.2 Pelvic angle. As determined using the 
pelvic angle gauge (GM drawing 78051-532 
incorporated by reference in Part 572, Subpart E 
of this Chapter) which is inserted into the H-point 
gauging hole of the dummy, the angle of the plane 
of the surface on the lumbar-pelvic adaptor on 
which the lumbar spine attaches is 23 to 25 
degrees from the horizontal, sloping upward 
toward the front of the vehicle. 



57.3 Legs. 

57.3.1 For a test dummy in the driver posi- 
tion. The upper legs of each test dummy rest 
against the seat cushion to the extent permitted by 
placement of the feet. The left knee of the dummy 
is positioned such that the distance from the outer 
surface of the knee pivot bolt to the dummy's 
midsagittal plane is six inches. To the extent prac- 
ticable, the left leg of the test dummy is in a verti- 
cal longitudinal plane, 

57.3.2 For a test dummy in the outboard pas- 
senger positions. The upper legs of each test 
dummy rest against the seat cushion to the extent 
permitted by placement of the feet. The initial dis- 
tance between the outboard knee clevis flange sur- 
faces is 11.5 inches. To the extent practicable, 
both legs of the test dummies in outboard pas- 
senger positions are in vertical longitudinal planes. 
Final adjustment to accommodate placement of 
feet in accordance with S7.4 for various passenger 
compartment configurations is permitted. 

57.4 Feet. 

57.4.1 For a test dummy in the driver posi- 
tion. The right foot of the test dummy rests on the 
undepressed accelerator with the heel resting as 
far forward as possible on the floorpan. The left 
foot is set perpendicular to the lower leg with the 
heel resting on the floorpan in the same lateral 
line as the right heel. 

57.4.2 For a test dummy in the front outboard 
passenger position. The feet of the test dummy 
are placed on the vehicle's toeboard with the heels 
resting on the floorpan as close as possible to the 
intersection of the toeboard and floorpan. If the 
feet cannot be placed flat on the toeboard, they are 
set perpendicular to the lower legs and placed as 
far forward as possible so that the heels rest on the 
floorpan. 

57.4.3 For a test dummy in either of the rear 
outboard passenger positions. The feet of the 
test dummy are placed flat on the floorpan and 
beneath the front seat as far as possible without 
front seat interference. If necessary, the distance 
between the knees can be changed in order to 
place the feet beneath the seat. 



PART 571; 214-9 



(Rev. 5/21/92) 



S8 Phase-in of dynamic test and performance 
requirements. 

58.1 Passenger cars manufactured on or 
after September 1, 1993 and before September 
1, 1994. 

S8.1.1 The number of passenger cars complying 
with the requirements of 53(c) shall be not less 
than 10 percent of — 

(a) The average annual production of passenger 
cars manufactured on or after September 1,1990, 
and before September 1, 1993, by each manufac- 
turer; or 

(b) The manufacturer's annual production of 
passenger cars during the period specified in S8.1. 

58.2 Passenger cars manufactured on or 
after September 1, 1994 and before September 
1, 1995. 

S8.2.1 The number of passenger cars complying 
with the requirements of S3(c) shall be not less 
than 25 percent of — 

(a) The average annual production of passenger 
cars manufactured on or after September 1, 1991, 
and before September 1, 1994, by each manufac- 
turer; or 

(b) The manufacturer's annual production of 
passenger cars during the period specified in S8.2. 

58.3 Passenger cars manufactured on or 
after September 1, 1995 and before September 
1,1996. 

S8.3.1 The number of passenger cars complying 
with the requirements of S3(c) shall be not less 
than 40 percent of— 

(a) The average annual production of passenger 
cars manufactured on or after September 1, 1992, 
and before September 1, 1995, by each manufac- 
turer; or 

(b) The manufacturer's annual production of 
passenger cars during the period specified in S8.3. 

58.4 Passenger cars produced by more than 
one manufacturer. 



S8.4.1 For the purposes of calculating average 
annual production of passenger cars for each 
manufacturer and the number of passenger cars 
manufactured by each manufacturer under S8.1, 



S8.2, and S8.3, a passenger car produced by more 
than one manufacturer shall be attributed to a sin- 
gle manufacturer as follows, subject to S8.4.2 — ^ 

(a) A passenger car which is imported shall be 
attributed to the importer. 

(b) A passenger car manufactured in the United 
States by more than one manufacturer, one of 
which also markets the vehicles, shall be attrib- 
uted to the manufacturer which markets the 
vehicle. 

S8.4.2 A passenger car produced by more than 
one manufacturer shall be attributed to any one of 
the vehicle's manufacturers specified by an 
express written contract, reported to the National 
Highway Traffic Safety Administration under 49 
CFR Part 586, between the manufacturer so speci- 
fied and the manufacturer to which the vehicle 
would otherwise be attributed under S8.4.1. 

[S9 Phase-in of side door strenqth require- 
ments for multipurpose passenqer vehicles, 
trucks and buses. 

[S9.1 Multipurpose passenqer vehicles, trucks 

and buses manufactured on or after Septem- d^ 

ber 1, 1993 and before September 1, 1994. • 



[S9.1.1 The combined number of multipurpose 
passenger vehicles, trucks and buses with a 
GVWR of 10,000 pounds or less complying with 
the requirements of S3(a)(3) shall not be less than 
90 percent of — 

[(a) The average annual production of multi- 
purpose passenger vehicles, trucks and buses with 
a GVWR of 10,000 pounds or less manufactured 
on or after September 1, 1990 and before Septem- 
ber 1, 1993 by each manufacturer; or 

[(b) The manufacturer's annual production of 
multipurpose passenger vehicles, trucks and buses 
with a GVWR of 10,000 pounds or less during 
the period specified in S9.1. 

[S9.1 .2 Walk-in vans, vehicles which do not have 
any side doors that can be used for occupant 
egress, vehicles which exclusively have doors of 
the types specified in S3(e), and vehicles specified 
in S9.2.3 may be excluded from all calculations of 
comphance with S9. 1 . 1 . ^ 



(Rev. 7/13/92) 



PART 571; 214-10 



[S9.2 Multipurpose passenger vehicles, 
trucks and buses produced by more than one 
manufacturer. 

[S9.2.1 For the purposes of calculating average 
annual production of multipurpose passenger 
vehicles, trucks and buses with a GVWR of 
10,000 pounds or less for each manufacturer and 
the number of multipurpose passenger vehicles, 
trucks and buses with a GVWR of 10,000 pounds 
or less manufactured by each manufacturer under 
S9.1,l, a vehicle produced by more than one 
manufacturer shall be attributed to a single manu- 
facturer as follows, subject to S9.2.2 — 

[(a) A vehicle which is imported shall be 
attributed to the importer. 

[(b) A vehicle manufactured in the United 
States by more than one manufacturer, one of 
which also markets the vehicle, shall be attributed 
to the manufacturer which markets the vehicle. 



[S9.2.2 A vehicle produced by more than one 
manufacturer shall be attributed to any one of the 
vehicle's manufacturers specified by an express 
written contract, reported to the National Highway 
Traffic Safety Administration under 49 CFR Part 
586, between the manufacturer so specified and 
the manufacturer to which the vehicle would 
otherwise be attributed under S9.2.1. 

[S9.2.3 Each multipurpose passenger vehicle, 
truck and bus with a GVWR of 10,000 pounds or 
less that is manufactured in two or more stages or 
that is altered (within the meaning of §567.7 of 
this Chapter) after having previously been cer- 
tified in accordance with Part 567 of this Chapter 
is not subject to the requirements of S3(a)(3). (57 
F.R. 30917— July 13, 1992. Effective: September 1, 
1993.)] 

July 13, 1992 
57 F.R. 30917 



PART 571; 214-11 



PREAMBLE TO AN AMENDMENT TO FEDERAL MOTOR VEHICLE 

SAFETY STANDARD NO. 217 

Bus Window Retention and Release 

(Docket No. 88-21 ; Notice 3) 
RIN 2127-AC88 



ACTION: Final rule. 

SUMMARY: This rule amends Federal Motor 
Vehicle Safety Standard No. 217, Bus Window 
Retention and Release, by revising the minimum 
requirements for school bus emergency exits and 
improving access to school bus emergency doors. 
Instead of requiring all school buses to have the 
same number of exits, as the standard currently 
does, this rule sets requirements for minimum 
emergency exit space based upon the seating 
capacity of each bus. Thus, larger school buses are 
required to have an increased number of exits. 
This rule also requires school buses to provide 
improved access to side emergency doors. In addi- 
tion, this rule includes requirements to improve 
the visibility of school bus emergency exits. This 
rule is intended to facilitate the exiting of occu- 
pants from a bus after an accident and thus 
improve the likelihood of their survival. 

EFFECTIVE DATE: This rule is effective May 2, 
1994. 

SUPPLEMENTARY INFORMATION: 

Background 
School buses are an extremely safe means of 
transportation. The most recent available informa- 
tion (i.e., data for the 1989-90 school year) 
indicates that approximately 370,000 public 
school buses traveled over 3.5 billion miles to 
transport over 22 million children to public 
schools. In its May 1989 report, "Improving 
School Bus Safety," the National Academy of 
Sciences estimated that another 20,000 school 
buses traveled 0.5 billion miles to transport 3 mil- 
lion school children to private schools. The safety 
record of school buses in protecting school bus 
occupants while traveling these billions of miles 
is impressive. On a vehicle-mile basis, school 
buses are about four times safer than passenger 



cars. Despite this outstanding safety record, 
school bus crashes do occur and occasionally seri- 
ous injuries and fatalities result. 

An important factor in minimizing post-crash 
injuries and deaths on buses is the speed and ease 
with which occupants can evacuate the vehicle in 
an emergency. When Standard No. 217, Bus Win- 
dow Retention and Release, originally became 
effective on September 1, 1973, it required that 
buses other than school buses have exits whose 
combined area, in square inches, equaled or 
exceeded 67 times the number of designated seat- 
ing positions. The type of exit used to comply 
with this requirement was left to the choice of the 
manufacturer, although the agency assumed that 
most manufacturers would meet the standard pri- 
marily by installing push-out side windows. 

School buses were excluded from this require- 
ment for the reasons explained in the notice of 
proposed rulemaking [NPRM]: 

In view of discipline problems associated with 
mandatory quick-release and exit devices throughout a 
school bus which may interfere with the school bus 
driver's task, and the added risk of children falling 
from moving school buses, push-out windows for 
school buses would remain optional. 35 PR 13025; 
August 15, 1970. 

The Standard did require that when a school 
bus was voluntarily equipped with push-out win- 
dows or with other emergency exits, those exits 
must confomi to the same requirements specified 
in the Standard for exits in buses other than 
school buses. 

In response to the Motor Vehicle and School- 
bus Safety Amendments of 1974 (Pub. L. 93- 
492), Standard No. 217 was amended to include 
emergency exit requirements for school buses. 
Instead of simply specifying that the total com- 
bined area, in square inches, of all the exits had 
to equal or exceed 67 times the number of des- 



PART 571; S 217— PRE-23 



ignated seating positions, and leaving the choice 
of exit type to the manufacturer, the agency 
required (and continues to require) that all new 
school buses have either (1) one rear emergency 
door, or (2) "one emergency door on the 
vehicle's left side that is in the rear half of the 
bus passenger compartment and is hinged on its 
forward side, and one push-out rear window." 
Like all of the agency's safety standards for 
motor vehicles. Standard No. 217 is a minimum 
safety standard, in this instance specifying the 
fewest permissible number of emergency exits for 
a school bus. 

In May 1988, 27 persons died of smoke inhala- 
tion in the fire resulting from the high-speed 
crash of a pick-up truck (driven by a drunk 
driver) and a used school bus in Carrollton, Ken- 
tucky. Several factors were involved in this tragic 
event, which represented the first fire-related 
occupant deaths on a school bus-type vehicle 
since NHTSA began compiling statistics on traffic 
fatalities in 1975. Some observers suggested that 
more occupants might have survived the fire if 
the bus had been equipped with additional (or 
more accessible) emergency exits. That bus had 
been manufactured in March 1977, shortly before 
the new NHTSA school bus safety standards took 
effect, including upgraded requirements for Stand- 
ard No. 217. This crash focused considerable pub- 
lic interest on several school bus safety issues, 
including emergency exits, as well as on the 
continuing problem of drunk driving. More 
recently, attention was again focused on school 
bus exits by the September 1989 crash in Alton, 
Texas, in which a tractor semi-trailer struck a 
school bus, which then rolled into a water-filled 
gravel pit. Twenty-one students drowned as a 
result of this crash. 

Following the Carrollton crash, NHTSA under- 
took a comprehensive review of its vehicle stand- 
ards and other programs for school bus safety, 
and published a summary report in November 
1988. That report noted the excellent overall 
safety record of school buses, but also highlighted 
areas where further improvements might be made. 
The National Academy of Sciences [NAS] 
reached similar conclusions in its report on school 
bus safety, issued in May 1989. 

In November 1988, NHTSA issued an 
advanced notice of proposed rulemaking 
[ANPRM] on whether to upgrade Standard No. 
217 to specifically enhance the requirements for 



school bus emergency exits (53 FR 44627; 
November 4, 1988). The notice explored whether 
rulemaking to require additional emergency exits ^ 
was warranted. It posed a series of 24 questions W 
divided into six categories: safety need, require- 
ments for additional exits, the effect of additional 
exits on other aspects of safety, cost of additional 
exits, encouraging the correct use of emergency 
exits, and other factors incident to requiring more 
emergency exits. NHTSA received 49 comments 
in response to the ANPRM. The commenters 
included Federal, State and local government 
agencies, local school districts, pupil transpor- 
tation services and associations, bus and equip- 
ment manufacturers, and the general public. 

After considering the responses to the Novem- 
ber 1988 ANPRM, NHTSA issued an NPRM 
proposing to amend Standard No. 217 to require 
that the minimum emergency exit space on school 
buses be based upon the seating capacity of the 
school bus so that emergency exit capability 
would be proportional to the maximum occupant 
capacity of the school bus and the school bus 
emergency exits requirements would be com- 
parable to the requirements for non-school buses 
(56 FR 11153; March 15, 1991). The NPRM pro- 
posed two options for how the additional emer- ^ 
gency exit space required by the proposed for- 
mula would be provided. That notice described 
the options as follows: 

Option A would provide that all additional exits 
required under the proposal be side exit doors. * * * 
Option B would require likewise, that where one addi- 
tional exit is required, it must be a side exit emergency 
door, but that where the additional exit space required 
exceeds the area created by that door (1080 square 
inches), the next 540 square inches of exit space must 
be provided by a roof exit, and the next 540 square 
inches provided by a second roof exit. The maximum 
credit for one roof exit would be 540 square inches, 
regardless of its actual size. If additional exit space 
beyond that provided by the side exit door and two 
roof exits is required (i.e., more than 2160 square 
inches of additional exit space is required), the pro- 
posal would require a second additional side exit emer- 
gency door. * * * 

The location for emergency exits under each 
option was specified. Additionally, the NPRM 
proposed to require that: Roof exits have a for- 
ward hinge and comply with the emergency . 
release requirements of S5.3; emergency exit « 
doors have a device to cause them to remain open 



PART 571: S 217— PRE-24 



once they have been opened past a certain point; 
seats adjacent to side emergency exit doors have 

)y\] flip-up seat bottoms; and the outline of school bus 
-^ emergency exits be marked with retroreflective 
tape on both the interior and exterior sides of the 
bus. 

NHTSA received 29 comments in response to 
this NPRM. All of these comments were consid- 
ered while formulating this final rule, and the 
most significant comments are addressed below. 

The most significant difference between the 
final rule and the NPRM concerns the means by 
which the additional emergency exit space will be 
provided. The requirement in the final rule is 
most similar to Option B in the NPRM, in that 
the first additional exit must be a side door and 
the second additional exit must be a roof exit. 
However, the final rule allows manufacturers to 
choose between side door exits, roof exits, and 
window exits in providing any additional required 
exit space. Additionally, the exact location of 
additional emergency exits is no longer specified. 
The final rule also differs from the NPRM in the 
types of markings that must be provided for 
emergency exits. 

r 1 . Capacity-based Emergency Exit Requirements 

The NPRM proposed to require that school 
buses provide minimum emergency exit spaces 
equal, in square inches, to 67 times the number 
of seating positions. Several commenters, includ- 
ing the National Transportation Safety Board 
[NTSB], the National School Transportation 
Association [NSTA], and several states, specifi- 
cally voiced support for capacity-based emer- 
gency exit requirements for school buses. How- 
ever, the Minnesota Department of Education 
[Minnesota] stated its belief that "the rule as pro- 
posed goes too far in trying to prevent or mini- 
mize damages from events that are extremely 
rare. Greater safety can be provided by targeting 
funds to other areas, such as driver training." The 
agency acknowledges the extremely safe record of 
school buses, but believes that it is important to 
safeguard against catastrophic-type crashes by 
ensuring that the occupants of school buses have 
adequate amounts of emergency exit space 
located in several locations throughout the bus. 
This is particularly important as more higher- 
capacity school buses are being manufactured. 
Based upon information in the annual statistical 
issue of "School Bus Fleet Magazine." in 



comparing 1991 to 1987, the number of Type C 
buses (24-76 passengers) sold decreased by 
approximately 8,000, while the number of Type D 
buses (78 passengers and over) sold increased by 
approximately 5,600. 

Additionally, while the agency recognizes the 
importance of school bus driver training pro- 
grams, it notes the importance of school bus driv- 
ers having the best equipment available to them 
in order to do their job. Even the best drivers can- 
not do their best with inferior equipment. Con- 
versely, the best equipment in the hands of 
untrained drivers does not guarantee the safe 
operation of a school bus. 

The Oregon Department of Education [Oregon] 
agreed that a capacity-based method for determin- 
ing the amount of emergency exit area should be 
adopted, but stated that using the same formula 
leaves a discrepancy between school buses and 
non-school buses. Oregon believed that school 
buses establish the maximum seating capacity 
based on a 13 inch wide seat space per individual, 
while non-school buses use a 15-18 inch space 
for a seating position. Oregon suggested this dif- 
ference be taken into consideration by either 
developing "a more compatible seating position 
definition * * * or by utilizing a reduced square 
inch criteria * * * for the determination of num- 
ber of required exits." 

There is no specific mention of a 13 inch seat- 
ing width in any safety standard. Oregon appar- 
ently based the 13 inch figure on the requirements 
of Standard No. 222, School Bus Passenger Seat- 
ing and Crash Protection. Section S4.1 of Stand- 
ard No. 222 calculates the maximum number of 
seating positions on a school bus bench seat by 
dividing the seat width by 15, and rounding the 
result to the nearest whole number. Using the 
industry "standard" seat width of 39 inches, the 
calculated maximum number of seating positions 
is 3 (39/15 = 2.6, rounded to 3). If one then 
divides the actual seat width (39 inches) by the 
calculated maximum number of seating positions 
(3), a 13 inch seating width can be inferred. This 
requirement is intended to ensure that the seat 
will be constructed to provide adequate crash 
protection when occupied by the maximum num- 
ber of passengers. Many of those passengers are 
likely to be younger and smaller than the typical 
passengers who ride in non-school buses. 

It appears that Oregon's concerns stem from 
the resulting number and cost of additional emer- 



PART571: S 217— PRE-25 



gency exits for school buses. If the agency 
adopted Oregon's suggestions for calculating the 
total amount of emergency exit space, a smaller 
number of exits would result. The agency believes 
that it is appropriate to base the emergency exit 
requirements for school buses on the maximum 
potential capacity of the bus rather than a lesser 
number, just as it is appropriate to base the crash 
protection requirements on the maximum potential 
capacity of each seat. School buses are often 
operated at or near capacity. Further, it is impor- 
tant to ensure that adequate emergency exit space 
is available no matter whether the school bus is 
filled with kindergarten-size students or high 
school-size students. Therefore, the final rule pro- 
vides that "(t)he area in square inches of unob- 
structed openings for emergency exit shall collec- 
tively amount to at least 67 times the number of 
designated seating positions in the bus." 

2. Option A (Emergency Exit Doors} or Option B 
(Doors and Roof Hatches) 

As explained previously, the NPRM proposed 
two options for adding emergency exits to school 
buses. Option A would have required that only 
side emergency exit doors be installed to meet the 
proposed additional emergency exit requirements. 
Option B would have required that a combination 
of side emergency exit doors and roof hatches be 
installed to meet the additional emergency exit 
requirements. 

Several commenters expressed support for 
Option A. However, many of these also expressed 
support for roof hatches. For example, Oregon 
stated that Option A "appears to provide the most 
equal distribution of emergency exits," but "rec- 
ommended that Option A be amended to include 
at least 1 roof exit." 

Most commenters expressed support for Option 
B or a variation of it adopted by the 11th 
National Conference on School Transportation. 
But many of these commenters also expressed 
support for even greater usage of roof hatches 
than Option B would have required. For example, 
the Arizona Department of Transportation 
[Arizona-DOT] noted that buses with a capacity 
of "48 passengers or less should be required to 
have at least one roof hatch." The Iowa Depart- 
ment of Education [Iowa] stated that Option B 
should be adopted, but that it should be "amend- 
ed to require at least one emergency roof escape 
for most, if not all school bus applications." 



Only the Colorado Department of Education 
[Colorado] expressed total opposition to roof 
hatches, and therefore to Option B. It expressed A 
technical concerns with roof hatches, particularly 
the "draft effect" of a roof hatch in a fire, as 
well as the potential dangers of dripping plastic 
from the hatch in a fire. Colorado also questioned 
whether or not the installation of a roof hatch 
would compromise a bus's ability to withstand 
rollover crashes. (A discussion of these concerns 
appears under Section 5, Roof Exits — Design and 
Size.) Further, it noted that in 5 years, only .7 
percent of the Colorado school bus crashes have 
involved a bus rolling over on its side. This 
means that "(s)tudents would not have had the 
need to use roof hatches as an exit 99.3% of the 
time." 

A number of commenters expressed strong 
convictions on the efficacy of various types of 
emergency exits. The NSTA supported "the use 
of push-out windows, side door or roof hatches to 
meet the emergency exit space requirements. The 
type of exit used to comply with the requirement 
should be the choice of the purchaser and manu- 
facturer." The Montana Office of Public Instruc- 
tion [Montana] believed that the states should ^ 
have "some choice in choosing emergency escape ^ 
windows, doors or roof hatches." 

The Eagle County Colorado School District 
[Eagle County] noted that while it supported the 
need for more emergency exits, it believed 
"(d)ifferences among school districts such as in 
terrain and types of pupils transported must 
necessitate local decisions on the number, type 
and location of emergency exits." The Salem- 
Keizer Oregon Public Schools [Salem-Keizer] 
supported the agency's proposals for establishing 
emergency exit requirements based on school bus 
capacity, however, it believed push-out windows 
serve a useful purpose. It liked the "approach for 
providing a variety of exits for meeting a variety 
of uncertainties," and asked that the agency not 
"rule against push-out windows!" 

Based on the comments, the agency believes 
that there are benefits to providing a variety of 
emergency exit types distributed throughout the 
bus as a precaution against a wide variety of 
potential emergency exit situations. Roof hatches 
would be a very beneficial type of emergency exit 
when the bus is on its side; however, it would be ^ 

difficult for many students to use roof exits in 
other situations. It is also possible to envision a 



PART 571; S 217— PRE-26 



situation in which a bus comes to rest in a posi- 

^^ tion where one or more emergency exits on a side 

\j would be too close to a tree, pole, guardrail, 

' bridge abutment or other vehicle to allow it to 

open, or to open completely. In such an instance, 

it would be useful to have emergency exits 

distributed in other areas of the bus. Accordingly, 

the agency has decided that school buses should 

have a variety of exit types distributed throughout 

the passenger compartment. 

The agency has determined that after calculat- 
ing the total amount of additional emergency exit 
area [AEEA] needed for a school bus, using the 
formula proposed in the NPRM, the first addi- 
tional amount of emergency exit area must be met 
with a side emergency exit door; the second addi- 
tional amount of emergency exit area must be met 
with an emergency roof exit. Unlike Option B in 
the NPRM, however, the final rule provides that 
any remaining emergency exit area can be met 
with either a side emergency exit door, a roof 
emergency exit, or an emergency exit window. 
The specification of a side emergency exit door 
as the first priority is consistent with the NPRM 
which noted that, "if a bus is required to have 
^ only one additional exit * * *, that exit should be 
fj a side exit emergency door." Allowing AEEA to 
be met with an emergency exit window in some 
circumstances, however, differs from the agency's 
position in the NPRM. 

In the NPRM, the agency stated three reasons 
why it did not want to encourage the use of push- 
out windows. First, push-out "windows are usu- 
ally higher off the ground and smaller in size than 
exit doors, which make them difficult for school 
age occupants to use." Second, "push-out win- 
dows are almost never used as a means of escape 
during school bus evacuation drills." Third, 
"push-out windows are likely targets of tamper- 
ing." (56 FR 11153, 11155) 

Nearly all commenters responding to the 
NPRM expressed an opinion concerning push-out 
windows. Most of these comments were based on 
the commenters' own successful experiences with 
such devices. For example, the Lake Oswego 
Oregon School District [Lake Oswego] stated that 
it has used push-out windows for nearly twenty 
years and that push-out windows "are at no 
greater risk of 'tampering' than any other emer- 
I gency exit. (T)hey certainly are of less of a threat 

of students falling if they 'play' with them, than 
a side door." Minnesota believed that "pushout 



windows will maintain structural integrity of the 
vehicle better than numerous side emergency 
doors." Summing up the sentiment of com- 
menters like these. Blue Bird stated that "(i)n the 
final analysis. State governments have the ulti- 
mate responsibility for selecting the features that 
they believe will best protect the safety of the 
passengers they transport." 

Given the almost uniformly negative response 
to the agency's position on push-out windows, the 
agency reexamined its position. First, given the 
experiences with tampering reported by the com- 
menters and that students may be sitting near side 
emergency doors, the agency no longer believes 
that push-out windows are a more likely target for 
tampering than an emergency exit door. While the 
agency continues to believe that push-out win- 
dows are less likely to be used in an emergency, 
the agency does not have any accident data to 
suggest that these windows are unsafe. Given that 
a large number of school districts currently 
require push-out windows in addition to the 
requirements of Standard No. 217 and have not 
reported any problems with them, the agency has 
been persuaded to allow push-out windows to be 
counted towards the AEEA requirements for some 
buses. Since the first amount of AEEA must be 
met with a side emergency door, the second 
amount of AEEA with a roof exit, only large- 
capacity buses, typically those with a seating 
capacity exceeding 70, will be able to take advan- 
tage of this option. 

NHTSA suggests that States and school dis- 
tricts consider the agency's concerns about the 
use of push-out windows when choosing between 
side doors, roof exits and push-out windows for 
larger school buses. For States and school districts 
that allow or require push-out windows in school 
buses, the agency suggests further that training 
programs include instruction in the use of these 
windows. 

3. Emergency Exit Doors 
While there were a number of comments to the 
docket in support of requiring only emergency 
exit doors and roof hatches, some commenters 
expressed concerns over the structural impact of 
additional side emergency exit doors. Thomas 
Built Buses [Thomas Built] stated that in terms of 
intrusion, it has been shown "that the structural 
integrity of the area around the side emergency 
door can be just as sound as an area along the 



PART 571; S 217— PRE-27 



side of the bus that does not have a side emer- 
gency door." However, on the subject of fatigue 
strength. Thomas Built has "seen evidence that 
the bus's fatigue strength has been compromised 
when a side door is installed on various types and 
brands of buses. This evidence shows up after 
years of use and is in the form of cracked struc- 
tural members and panels." The placement of the 
door, depending on the "body length, front 
engine, rear engine, and operating conditions," 
can have "detrimental effects on structural 
fatigue." "Problems can show up early (1-2 
years) or later (3-10 years)." 

The agency does not believe the fatigue 
strength concerns expressed by Thomas Built are 
unique to side emergency exit doors. In-use 
fatigue problems can result from a variety of 
operational factors, including climate and roadway 
factors, that can affect many areas in all types of 
buses. 

With respect to these "fatigue strength" con- 
cerns, the agency notes that: (1) rear-engine 
school buses have been equipped with a left side 
emergency exit door since 1977; (2) several 
States (e.g., California, New York, and Washing- 
ton) already require additional side emergency 
doors in their school buses: (3) a large number of 
school buses are equipped with wheelchair lifts 
which essentially represent an oversized side 
emergency exit door; and (4) these buses do not 
appear to be suffering from large numbers of 
design structural integrity problems or fatigue 
strength life cycle problems. For these reasons, 
the agency believes requiring a single side emer- 
gency exit door in school buses currendy 
equipped with a rear emergency door or an addi- 
tional side emergency exit door on a school bus 
with a left side emergency exit door will not 
compromise the structural or life cycle character- 
istics of school buses. 

4. Window Size 
Three commenters directly addressed the size 
of the standard (non-emergency exit) windows on 
school buses. These comments attempted to sepa- 
rate emergency evacuation situations into two 
types. The first were the routine evacuations 
where time is not necessarily critical and the serv- 
ice entry door and other floor level emergency 
exits would be utilized. The second were cata- 
strophic-type crashes where the school bus occu- 
pants have to evacuate the vehicle as fast as pos- 



sible. In its comments to the NPRM, the Califor- 
nia Department of Education [California] noted 
that "NHTSA could have also enhanced pas- ^ 
senger safety by requiring the passenger window 
opening to be at least 12" by 22" in area." (Cur- 
rently, most school buses are built with split-sash 
windows which drop to provide an opening of 9" 
high X 22" wide.) California stated that while 
each window should not be a designated emer- 
gency exit, "a larger window opening would pro- 
vide passenger(s) in each seat location direct 
egress from the bus in a catastrophic accident 
similar to the accidents in Carrollton, Kentucky 
and Alton, Texas. Many lives may have been 
saved if only the passenger windows would have 
provided a large enough opening to permit the 
passengers to escape." A similar comment was 
submitted by Washington. 

TAM-USA stated that one of the conclusions 
from the NTSB's investigation of the Alton, 
Texas, school bus crash was that "larger vertical 
openings of the side windows would have 
improved the occupants' ability to escape." 
TAM-USA further commented that establishing 
minimum window size openings as a: 

remedy for total and immediate evacuation from cata- ^ 
strophic accidents * * * serves a number of purposes. 
First, it recognizes that such accidents are unique, and 
normal rules of, and training for, evacuation in such 
accidents do not apply. Second, it recognizes that no 
single set of measures can address every possible 
accident scenario. Third, addressing the problem in this 
way permits NHTSA to focus the rest of its thinking 
and logic on the vast majority of accidents which are 
not catastrophic, and to which passenger training and 
coordination with safety features can produce optimum 
and measurable results. 

Finally, TAM-USA stated that in the Alton crash 
"push-out windows would not have worked, since 
each window would have had several hundred 
pounds of water pressure on it." Accordingly, it 
believed "simple sliding passenger windows, with 
large window openings, are far less expensive, 
could be applied to the entire bus, and do not 
possess most of the problems associated with 
push-out windows." 

Along the same vein. Blue Bird stated that it 
has several side emergency exit designs under 
development, including a vertical slide open win- 
dow and side exit hatch or shorter emergency exit L 
door. In order to encourage, and certamly not to 
prohibit, further development and use of these 



PART 571: S 217— PRE-28 



types of exits, Blue Bird believed language should 
be included in the school bus requirements that 
h would provide for emergency exit side windows 
with a maximum amount of credit of 536 square 
inches. 

While the agency understands the comments 
concerning the wisdom of larger standard win- 
dows in school buses to facilitate evacuation dur- 
ing catastrophic situations, it is concerned about 
the potential negative aspects of larger windows. 
Specifically, the agency is concerned about the 
greater potential danger to a child who sticks a 
hand, arm, or head out of the window while the 
bus is in motion. It is clearly easier for a child 
to hang out of a 12 inch x 22 inch window than 
a 9 inch x 22 inch window. The agency recog- 
nizes that some state and local school districts are 
currently using school buses with larger windows, 
without large numbers of incidents where children 
are hurt because of them. Taken all together, the 
infomiation available to the agency appears to 
provide some evidence that the potential benefits 
may be greater than the potential risks. 

As was stated in Washington's comments, 
states do not want "every school bus window to 
\ be considered a designated exit." If windows 
were so regarded, each of them would be required 
to meet the Standard No. 217 requirements for 
emergency exits, including audible warnings, 
locking devices, labeling, etc. Also, as was stated 
in the TAM-USA comments, the importance of 
evacuation routes at every seat is relevant only in 
catastrophic crashes. Since the overwhelming 
majority of school bus evacuations do not occur 
in connection with catastrophic crashes, the 
agency believes there is a need for designated 
emergency exits, which can be accomplished with 
doors, hatches, and/or push-out windows. How- 
ever, the agency does not believe there is suffi- 
cient justification to support a Federal mandate 
for non-designated emergency exits, which could 
be obtained from larger school bus window open- 
ings throughout the bus. 

Accordingly, while the agency supports the 
concept of each student having a personal escape 
route, whether it be through a designated or non- 
designated emergency exit, it does not believe 
there are sufficient grounds for establishing mini- 
mum window opening sizes for non-designated 
emergency exits. However, the agency notes that 
the use of larger windows is permissible for those 
states that wish to have them. 



5. Roof Exits— Design and Size 
Support for roof exits came from a wide range 
of commenters. As noted earlier, some com- 
menters (Iowa and Arizona-DOT) went so far as 
to state that all school buses should be equipped 
with at least one roof hatch. Only Colorado 
expressed concern about roof exits, particularly in 
a fire situation where a roof hatch could create a 
"chimney effect" and worsen the fire. While 
Colorado is correct that an open roof hatch would 
create a chimney for smoke and heat to escape, 
such a result is desirable. Heat and smoke are at 
least as much of a threat to bus occupants as the 
fire itself. While the open roof hatch would help 
vent heat and smoke out of the bus, it can also 
result in more oxygen being drawn into the bus. 
While this additional oxygen will provide addi- 
tional "fuel" for the fire, it will also provide 
additional oxygen for anyone in the bus. On bal- 
ance, the agency believes the positive aspects of 
open roof hatches in a bus fire outweigh any 
potential negative aspects. 

A number of commenters discussed their 
beliefs that recessed roof hatch requirements, as 
mentioned in the NPRM, would be more suscep- 
tible to binding in a crash and would require 
some type of internal draining system that would 
add cost to the bus. Thomas Built stated that 
"(r)ecessing the hatch would create greater prob- 
lems than the 'predicted' problem attempting to 
be solved." It cites potential jamming from body 
twist, as well as water drainage (and rust) prob- 
lems. Blue Bird stated its belief that current roof 
hatch designs are safe and added that it does not 
support recessed designs because they are "more 
likely to be jammed shut in an accident." Two 
roof hatch manufacturers, Transpec and Salem 
Vent International [Salem Vent], also agreed that 
recessed vents would be more susceptible to bind- 
ing in a crash, and believed that the current over- 
lay roof hatch designs are the best. Based on 
these comments, the agency does not believe that 
overlay roof hatches are a safety problem or that 
it is necessary to require recessed roof exits. 

A number of commenters addressed the issue 
of roof exit size. The preamble to the NPRM 
stated that, "The maximum credit for one roof 
exit would be 540 square inches, regardless of its 
actual size." The proposed regulatory language 
stated that, "The roof exit shall provide an open- 
ing with a minimum clearance of 16 inches and 
an area of at least 540 square inches." Only 



PART 571: S 217— PRE-29 



Thomas Built makes a roof vent that meets the 
540 square inch requirement proposed in the 
regulatory text. There are no other known manu- 
facturers of a roof hatch that large. Transpect 
stated that they believe the proposed size require- 
ments "will obsolete virtually every roof exit 
design currently available; and force bus body 
manufacturers and equipment suppliers to spend 
potentially millions of dollars in re-designing and 
re-tooling." It suggested a minimum size of 20" 
X 20", which is "about 50% larger than the cur- 
rent minimum size" and will allow passage of the 
13" X 20" ellipsoid currently required for push-out 
windows under S5. 2.2(b) of Standard No. 217. 
Other commenters stated that additional leadtime 
would be needed while existing roof exits were 
redesigned to meet the minimum area require- 
ments. 

After reviewing the comments to the docket on 
this topic, the agency has decided to delete the 
requirement that the roof hatch have an area of at 
least 540 square inches. The agency was not 
aware that current roof exit designs did not meet 
the proposed requirements. However, the agency 
believes that a minimum size must be specified 
for roof hatches. Therefore, consistent with the 
NPRM. each open roof hatch must provide an 
unobstructed space of not less than 16 inches by 
16 inches. As with all other openings, there is no 
limit on the maximum size of the opening. The 
regulatory language has been revised accordingly. 

The NPRM also proposed that roof exits be 
operable from the outside to assist rescue person- 
nel in being able to open a roof hatch on an over- 
turned school bus in an emergency situation. 
Since no commenters objected to this require- 
ment, it is included in the final regulatory lan- 
guage. 

6. Location of Emergency Exits 
The NPRM proposed amending existing 
S5.2.3.1, governing minimum emergency exit 
locations, to specify the location of the additional 
exits required by Options A and B. The NPRM 
stated, "(t)he agency is concerned that the 
required exits maximize emergency egress while 
not compromising the structural integrity of the 
vehicle." The NPRM then proposed specific loca- 
tions for the additional exits under both Options 
A and B. 

All of the comments concerning the location of 
any type of emergency exit supported the concept 



of an even distribution of the exits around the 
bus. However, the locations proposed in the 
NPRM were not always deemed possible or prac- ^ 
ticable. For example, Thomas Built stated that the 
left side emergency door on rear engine buses 
"cannot be placed at the extreme rear section 
* * * because of the interference with the engine 
compartment/davenport seat." Additionally, the 
company said that the left and right side emer- 
gency exit doors should not be "within the same 
post and roof bow panel space." 

Blue Bird stated that because of design restric- 
tions related to such items as wheelhousings, fuel 
filler necks, seat placements, etc., there are a 
number of problems in specifying side door loca- 
tions. Accordingly, Blue Bird "strongly rec- 
ommends that NHTSA conduct further research to 
detennine the effects and feasibility of requiring 
specific exit locations." 

Other commenters endorsed the even distribu- 
tion of emergency exits, but believed that states 
should have the flexibility of establishing the 
location of emergency exits. California believed 
"(t)he location of the side exit doors and roof 
vent/exits should be optional to each state." 

Washington, which has required additional side ^ 
emergency exit doors on most buses since 1954, ™ 
supported the concept of specifying the locations 
of emergency exits. Its experience indicated that 
if the locations of emergency exits are left to the 
discretion of the manufacturers, doors could be 
installed in a manner that "meets the letter of the 
law * * * (but) does not meet the intent of the 
requirement." 

Transpec commented that when two roof exits 
are utilized, "they should be located equidistant 
between the mid-point and the front and rear of 
the passenger compartment * * * jj^ other words 
the forward Va and the rearward Va of the overall 
passenger compartment length." This differs from 
the proposal of the forward Vi and rearward '/s. 
Transpec stated that its alternative would better 
minimize the distance any single passenger would 
have to travel to reach a roof exit. 

Based on the above, the agency has concluded 
that there are legitimate technical issues relative 
to establishing specific locations for side door 
exits in school buses. Differences in chassis and 
body designs among manufacturers would neces- 
sitate the establishment of standards on a make/ 4 
model basis, which could hinder school bus safety 
improvements in the future. The agency has con- 



PART 571: S 217— PRE-30 



eluded that emergency exits should be evenly 
distributed throughout the bus, to the extent pos- 
sible. For example, if an emergency exit door is 
added to a school bus with an existing rear door 
emergency exit, the additional door must be 
located on the left side of the bus and as close 
to the center of the bus as is practicable. If an 
emergency exit door is added to a school bus with 
an existing left side emergency exit door, the 
additional door must be located on the right side 
of the bus. 

With respect to roof hatches, the agency agrees 
with the location specifications suggested by 
Transpec because these specifications minimize 
the distance from the roof exits to the farthest 
school bus seat. Therefore, the agency has con- 
cluded that when a single roof hatch is installed 
in a school bus, it must be located as near as 
practicable to the longitudinal mid-point of the 
passenger compartment, and must be installed 
such that the centerline of the hatch is on the 
longitudinal centerline of the bus. When 2 roof 
hatches are utilized, they shall be located as near 
as practicable to the points equidistant between 
the longitudinal mid-point of the passenger 
compartment and the front and the rear of the 
I passenger compartment. When multiple roof 
hatches are utilized, they may be installed either 
on the longitudinal centerline of the bus or offset 
from the centerline. For each roof hatch that is 
installed in an offset manner, there must be 
another roof hatch offset an equal amount to the 
other side of the centerline. 

If a state chooses to install emergency exit win- 
dows in order to satisfy some of the exit space 
required by the standard, there must be an even 
number of such windows and they must be evenly 
distributed between the left and right side of the 
bus. 

Consistent with giving states the flexibility of 
selecting some of the types of emergency exits 
used (doors versus hatches versus windows), the 
agency has concluded that states are in the best 
position to specify the exact locations of emer- 
gency exits on school buses. The final rule, there- 
fore, establishes general requirements for school 
bus emergency exit locations. The agency antici- 
pates that the individual states will include more 
specific location information in their school bus 
specifications and work with the school bus 
manufacturers during the construction of their 
school buses to establish emergency exit locations 



that provide for the safe, organized, and efficient 
egress of passengers from all school bus seats. 

7. Improved Access to Emergency Exits 

The NPRM proposed that if school bus manu- 
facturers placed seats adjacent to a side emer- 
gency exit door, those seats must have flip-up 
bottoms in order to provide a path to the door. 
The path would have been somewhat less than 24 
inches wide. The location of the path in relation 
to sides of the door opening would have been 
fixed by a reference to the forward edge of the 
door. If this proposal were adopted, manufacturers 
not wishing to install flip-up seats would have 
had the option of complying by providing an 
open aisle to the side door. Under that option, the 
aisle would have extended the full width of the 
door, a minimum of 24 inches. 

The agency considered, but tentatively rejected, 
two more costly alternatives. One would have 
required the unobstructed passage of a rectangular 
parallelepiped (12" x 24" x 45") through each 
side door opening a distance of one foot inside 
the outside door frame edge. The other would 
have required the unobstructed passage of a 
rectangular parallelepiped through the door open- 
ing all the way to the center of the aisle, thereby 
creating a dedicated aisle to the side door. The 
path to the door created by the passage of the 
parallelepiped would not have been referenced to 
either the forward or the rearward edge of the 
door. Although the agency tentatively rejected 
both of these other options, the agency sought 
comment on them to aid in determining what 
requirements regarding access should be adopted. 

Several states and school districts, two bus 
manufacturers, and a national association sup- 
ported the proposal to require that seats adjacent 
to side emergency exit doors have flip-up seat 
bottoms. Oregon, Salem-Keizer, Minnesota, Eagle 
County, Thomas Built, TAM-USA, and NSTA 
indicated that they preferred providing a flip-up 
seat at side emergency exit doors, instead of a 
dedicated aisle, primarily because of perceived 
capacity loss and resulting additional costs associ- 
ated with the latter alternative. Thomas Built 
commented that if an aisle were mandated, the 
aisle should have a minimum width of 12 inches. 

Several states supported dedicated aisles. Mary- 
land did not support the use of flip-up seats. It 
did not believe a child should be allowed to sit 
next to a door, and that a clear aisle leading to 



PART 571; S 217— PRE-31 



the side door is just as important as a clear aisle 
leading to the rear emergency door. Washington 
preferred "a clear aisle to the side door.'" 
Washington added that it was "aware of the con- 
cern for lost seating capacity. However, unless the 
bus is already at maximum length, adding a 
longer bus body will regain any loss in seating 
capacity." While Washington did not have 
production data, it suspected that most buses are 
not produced at maximum length. 

Washington also noted that it has recently 
started purchasing flip-up seats and has already 
had "two incidences reported where children 
have stepped on the seat cushion in a fashion that 
allowed the leg to become lodged in between the 
seat cushion and the seat back. Once the leg was 
stuck, it was a major task to dislodge the leg. 
Such an occurrence would have been a disaster if 
it happened when the bus was being evacuated 
because of an emergency." For this reason, 
Washington believed that "(i)f the flip-up seat is 
allowed, there needs to be a performance require- 
ment that will not allow a child's foot to slip 
through the space between the seat cushion and 
seat back." 

Blue Bird favored requiring a dedicated aisle at 
least 12 inches wide. It expressed concern that 
"there is limited experience with the use of side 
emergency doors and access to these doors." 
Only four states require additional side emergency 
exit doors, and "two have no seat alignment or 
aisle clearance requirements to these doors." Blue 
Bird noted that Washington has recently required 
seat alignment and a clear aisle, and Kentucky 
has recently required a staging area at side emer- 
gency doors. Kentucky's requirement appears to 
have been adopted in response to the Carrollton, 
Kentucky crash. However, "(n)o field experience 
with this exit configuration has been accumu- 
lated." 

Blue Bird stated that the installation of a flip- 
up seat at side emergency exit doors instead of a 
dedicated aisle does not always eliminate a loss 
of capacity. It also noted that it is "not aware of 
a flip-up seat design that assures proper function- 
ing in all circumstances or that will totally elimi- 
nate possible pinching or entrapment potentials." 
Blue Bird further stated its concern that in "cer- 
tain accident scenarios, occupants could be 
thrown off the seat cushion, allowing it to flip up, 
and then be rebounded into the upright cushion 
which allows the potential for injury." Blue Bird 



cautioned "NHTSA to thoroughly evaluate the 
proposed requirement for flip-up seats at side 
emergency doors before specifying their use." ^ 

In view of the concerns expressed by com- 
menters regarding flip-up seat bottoms, the 
agency believes that the preferable manner of 
providing access to side emergency exit doors is 
through creating a dedicated aisle. However, the 
agency recognizes that some states believe flip-up 
seats are reasonable alternatives to providing 
access to side emergency exit doors. While rec- 
ognizing there are some advantages to a dedicated 
aisle over a flip-up seat, the agency does not 
believe there is sufficient justification or experi- 
ence to require dedicated aisles. Accordingly, the 
agency has decided to permit either dedicated 
aisles or seats with flip-up bottoms. The current 
Standard No. 217 language which allows a stand- 
ard school bus seat to be next to a side emer- 
gency exit door has been eliminated. No special 
provisions have been adopted to address the issue 
of entrapment since the agency lacks sufficient 
information to specify performance requirements 
for flip-up seats. 

The NPRM also requested comment on 
whether the agency should allow a tolerance in £ 

the relationship of a seat back to the forward edge • 

of a side emergency door opening. Thomas Built 
and Blue Bird suggested that the proposed lan- 
guage regulating the location of a seat back in 
relation to the forward edge of the side emer- 
gency door could be misinterpreted. Thomas Built 
suggested that the S.5.4.2.1(b) language be: "A 
vertical transverse plane tangent to the reamnost 
point of a seat back shall pass through any points 
between 0.5 inches forward of the forward edge 
of the door opening and 0.5 inches rearward of 
the edge." Blue Bird also suggested rewording of 
this section to say that: "the seat back shall be 
positioned such that the vertical transverse plane 
passes anywhere between points .5 inches forward 
or rearward of the door opening." Washington 
also agreed that some flexibility in seat back loca- 
tion relative to the side door must be allowed and 
suggested a "tolerance of one-half of the manu- 
facturers seat back thickness." 

After reviewing the proposal and the tentatively 
rejected alternatives, as well as the public com- 
ments, the agency has determined that a provision 
requiring that there be a seat back aligned with 4 

the forward edge of each side emergency exit 
door would be unnecessarily design restrictive. 



PART 571: S 217— PRE-32 



even if the agency were to provide a tolerance of 
0.5 inches. Since the requirement has the effect of 
requiring that a seat be installed immediately for- 
ward of a side door opening, it could have 
undesirable consequences. For example, a manu- 
facturer would be prohibited from placing a 
wheelchair securement location in that area, even 
though the areas near a side door might be the 
most logical area if a wheelchair lift were 
installed in that door. 

However, the agency has determined that the 
location of the path to the door should be ref- 
erenced to the real edge of the door to ensure 
access to the door release mechanism. Because 
side emergency exit doors are required to be 
hinged on their forward edge, the release mecha- 
nisms are located near the rearward edge of the 
door. Therefore, the agency has decided to require 
an aisle at least 12 inches wide, referenced to the 
rear edge of the emergency exit door. In addition, 
no seat or restraining barrier will be allowed to 
extend rearward of the forwardmost portion of the 
latch mechanism when it is in the latched posi- 
tion. Some latch mechanisms include a long lever 
that extends well forward of the 12 inch clear 
aisle required by this rule. A flip-up seat is 
allowed in the aisle area adjacent to a side emer- 
gency exit door so long as no portion of the seat 
bottom is within this aisle area when the seat bot- 
tom is in the up position. 

8. Three-Point Door Latch 
The NPRM requested comment on the likeli- 
hood of side door ejections because of additional 
side emergency exit doors on school buses. 
Additionally, the agency requested comment on 
whether additional or improved door exit mecha- 
nisms (e.g., a 3-point latching mechanism with 
latch points at the top, bottom, and side of the 
door) would reduce the risk of ejection. 

Several state and local school districts sup- 
ported the concept of providing multiple latches 
on side doors. Washington, for example, voiced 
its support by noting that "(a)ny time there are 
multiple latches to fail, the probability of failure 
is reduced." Washington and Eagle County 
believed that 3-point latches should be used on 
rear emergency exit doors as well. Oregon sup- 
ported a 3-point latching mechanism, provided it 
is "based on test data and the vehicles ability to 
meet overall construction standards." 



Blue Bird and Thomas Built stated that a side 
emergency exit door retention test would be more 
appropriate than requiring a 3-point latching 
mechanism. Thomas Built noted that passengers 
would not be ejected through current side emer- 
gency exit doors because of inadequate latching 
mechanisms. It stated that "(p)assengers inside 
the bus, impacting the door, would not exert 
enough force to cause the latch to fail." Thomas 
Built believed that "(a) detrimental effect from 
the three-point latch is possible jamming" in a 
crash. Blue Bird also asserted that "a 3-point 
latch mechanism could result in increased 
susceptibility to jamming in an accident." 

No commenters provided any information to 
suggest that side emergency exit doors on school 
buses are currently at potential risk of opening in 
a crash. The agency is aware that the July 1991 
crash of a school bus in Palm Springs, California, 
in which the school bus body separated from the 
bus chassis and was severely twisted during the 
high-speed crash into a series of large boulders, 
resulted in the opening of the left side emergency 
exit door. The National Transportation Safety 
Board has not completed its investigation of that 
accident to determine if there were any pas- 
sengers injured or killed because of the door 
opening during the crash. The structural damage 
to the bus body was so severe that it is hard to 
imagine that multiple door latches would have 
kept the door closed. The door appears to have 
opened due to severe damage to the bus body, not 
because a passenger was thrown against the door. 

After considering the comments of school dis- 
tricts and the bus manufacturers, the agency has 
concluded that, if a side emergency exit door 
retention problem existed, it would be more 
appropriate to develop a door retention test, rather 
than specifying a specific type of latching mecha- 
nism, e.g., a 3-point latch. Even with the recent 
crash in Palm Springs, California, the agency 
does not believe there is a safety problem with 
side emergency exit doors opening due to the 
force of passengers being thrown against them. 
Additionally, as with emergency roof exits, the 
agency is concerned about establishing require- 
ments that could increase the potential for jam- 
ming shut in a crash, as was suggested by Blue 
Bird and Thomas Built. Accordingly, the final 
rule does not include requirements for a 3-point 
latching mechanism for side emergency exit 
doors. 



PART 571: S 217— PRE-33 



9. Positive Door Opening Device 
The NPRM discussed the agency's beUef that 
an exit should not only be reachable, but also not 
shut once it has been opened, regardless of the 
orientation of the bus after a crash. The agency's 
concern was directed specifically to emergency 
exit doors. Accordingly, the NPRM proposed that 
each emergency exit door "be equipped with a 
device capable of bearing the weight of the door 
and keeping the door from closing past the point 
that is perpendicular to the side or rear of the bus 
once the door is opened to that point." 

The NTSB expressed its support for a device 
that would hold an emergency exit door open "to 
accommodate passenger egress, particularly in a 
rollover situation." This was one of the rec- 
ommendations that was included in the NTSB's 
report on the September 1989 Alton, Texas, 
school bus crash. Two bus manufacturers and four 
states also expressed their support for such a 
device. Thomas Built and Washington also noted 
that such devices were included in the require- 
ments of the 11th National Conference on School 
Transportation. Blue Bird requested an oppor- 
tunity to comment on the technical perfomiance 
requirements of such a device before it becomes 
a final rule. 

Based on the above support for such a device, 
the agency has concluded that a device to keep 
floor-level emergency exit doors from shutting 
after they have been opened is necessary on 
school buses. The requirements specified in the 
NPRM have been adopted. The technical require- 
ments for this aspect of Standard No. 217 are 
identical to those included in the NPRM. There- 
fore, the agency does not believe the opportunity 
requested by Blue Bird to review further the tech- 
nical requirements of this device is merited. 

]0. Improving the Conspiciiity of Emergency Exits 
A number of commenters supported the pro- 
posal to improve the conspicuity of emergency 
exits. However, there were some differences of 
opinion on how to accomplish the improved con- 
spicuity. The NPRM proposed to require a 1-inch 
wide strip of retroreflective tape to outline the 
inside and outside perimeter of each designated 
emergency exit opening. Additionally, the agency 
sought comment on whether school buses should 
be required to have an interior light source to illu- 
minate the retroreflective tape around the interior 
perimeter of emergency exits at night. 



Blue Bird commented that it is "unaware of 
any problems or concerns regarding emergency 
exit identification or operating instructions under ^ 
the current exit requirements" and suggests that 
NHTSA "establish and document a need for such 
markings before including this requirement in the 
final rule." It strongly recommended "that 
NHTSA construct and evaluate prototype vehicles 
and/or conduct field tests of this proposed 
requirement before finalizing the rule." Thomas 
Built also suggested that the effects of standard 
interior lighting on driver's night vision be 
studied. Transpec commented that reflective 
markings of roof exits would "not be difficult to 
accomplish" but questioned whether the need for 
such markings had been "established" and said 
that the "cost-effectiveness of such expenditures 
might be questioned." 

Minnesota did not believe retroreflective tape 
should be required at emergency exits. First, it 
noted that "(s)tudents usually ride the same bus 
every day and usually during periods of time 
when there is adequate light." Second, Minnesota 
is "particularly concerned that reflective material 
on the inside of the vehicle would create vision 
problems for the driver at night. The light from -- 
oncoming vehicle headlights could reflect off the ^ 
material and back to the driver's eyes via the 
inside mirror or the windshield." 

Thomas Built also stated that since 
retroreflective tape requires "a direct beam of 
light originating from the point of the observer" 
to function properly, it is unlikely that 
retroreflective tape would perform well on the 
inside of a school bus. "A stripe of fluorescent 
paint would probably be more useful than the 
reflective tape with respect to background lighting 
without direct lighting." "Retroreflective tape 
would work best on the outside of the exits where 
it is likely to be illuminated by rescuers or pass- 
ing car headlights." Several other commenters, 
such as NSTA, West Virginia, and Salem-Keizer, 
supported the use of reflective markings on emer- 
gency exits. 

Oregon supported making emergency exits 
more visible, but believed that establishing a 
"labeling criteria for emergency exits to include 
a retroreflective background material" is better 
than merely adding a 1-inch stripe of tape around 
the perimeter of the exit. Even in no-light or lim- l 

ited-light conditions, the words "Emergency " 

Exit" would be at least as visible as currently 



PART 571; S 217— PRE-34 



required. It based this recommendation on the fact 
that retroreflective tape is used for many other 

) purposes around school buses in various states, as 
well as on other vehicles, and it may not be clear 
what the tape represents. Using retroreflective 
tape to call attention to the words "Emergency 
Exit" seemed more reasonable to Oregon. 

Washington believed all emergency exits 
should be identified on the interior and exterior, 
and should be labelled with instructions for use. 
"These instructions and location markings will 
benefit students who walk to school and only ride 
school buses on field trips and extracurricular 
trips." 

3M Traffic Control Materials Division [3M] 
agreed with the proposal to provide retroreflective 
markings at all emergency exits and provided the 
necessary technical information, in terms of Mini- 
mum Specific Intensity per Unit Area (SIA), for 
the color yellow. The NPRM proposed to use the 
intensities from Standard No. 125, Warning 
Devices, which only covers the colors red and 
white. 3M noted that the "(r)eflective emergency 
exit markings visible from the exterior of the bus 
have the other benefit of alerting motorists. This 
^ provides an added benefit of accident preven- 
I tion." However, 3M believed "a two inch wide 
strip is needed (at the rear emergency exit) to pro- 
vide the important added benefit of crash avoid- 
ance made possible by making the vehicle visible 
at greater distances by fast approaching motor 
vehicles during times when headlights are being 
used. This two inch strip is consistent with the 
dimensions of other similar strips recommended 
in the 1990 National Standards for School Buses 
and Operations." 

3M stated that "(w)hen retro-reflective mark- 
ings are used in the interior of school buses 
equipped with passenger compartment electric 
lights, the reflective markings provide the added 
benefit of enhancing identification of exits while 
lights are operable. In situations where the electric 
system fails to function during the post crash 
situation, the reflective material will return light 
to any light source within hundreds of feet of the 
bus. Examples of these light sources include res- 
cuer flashlights, street and building lights and 
motor vehicles, to name only the most common 
sources." 
I Finally, 3M felt that the interior markings 

' "would be considerably more valuable if the 
markings were both retro-reflective and fluores- 



cent and therefore highly visible even during all 
light conditions without presence of a (sic) artifi- 
cial light source of any kind." 

After review of the above comments, the 
agency has concluded that there are legitimate 
concerns over the efficacy of requiring 
retroreflective tape on the inside perimeters of 
emergency exits. The agency believes that the 
issues raised by Minnesota and Thomas Built, 
with respect to mandatory interior lights and light 
reflected into the eyes of the driver, are legiti- 
mate. On the other hand, the agency has con- 
cluded that retroreflective tape identifying the out- 
side perimeter of emergency exits has significant 
potential benefit, for both post crash rescue and 
crash avoidance because of enhanced conspicuity 
of the bus. Accordingly, the final rule requires a 
minimum 1 inch wide strip of retroreflective tape, 
either red, white, or yellow in color, to be placed 
around the outside perimeter of the emergency 
exit opening, not the emergency exit itself. The 
required reflectivity properties of the tape will be 
provided in a Table, consistent with the require- 
ments for the reflective material allowed under 
Standard No. 131, School Bus Pedestrian Safety 
Devices. 

1 1 . Hinge Placement for Roof Exits and Side 

Emergency Exit Doors 

The NPRM proposed that roof hatches be 
hinged on the forward edge and that side emer- 
gency exit doors be hinged on the forward edge, 
as is currently required by Standard No. 217 for 
a single left side door. 

Transpec and NSTA supported the forward 
hinging for roof hatches, and the agency has 
adopted such a requirement in the final regulatory 
language. 

Thomas Built Buses noted an error in the pro- 
posed wording of S5. 2. 3. 2(b) under Option B. 
The proposed language required a left side emer- 
gency door which is hinged on its "rearward" 
side, rather than its "forward" side. This error is 
corrected in the final regulatory language. 

12. Warning Alarms for Roof Exits and Side 

Emergency Exit Doors 
The NPRM proposed that all emergency exits 
be equipped with a continuous audible alarm at 
the driver's position that sounds when the ignition 
is in the "on" position and the emergency exit 
release mechanism is not in the closed position. 



PART 571: S 217— PRE-35 



Transpec commented that roof exits do not 
need to be equipped with alarm devices because: 
(1) Roof exits are in "areas where it's virtually 
impossible for passengers to lean against them 
* * * let alone accidently fall through one;" (2) 
unlatched roof exits (for ventilation purposes) are 
seen in real-world operations, and an alarm 
"could distract the driver's attention"; and (3) 
"requiring alarms on roof exits will serve to 
discourage retrofit installations of roof exits on 
school buses * * * something that should be 
encouraged." 

The Arizona Department of Public Safety 
[Arizona-DPS] forwarded a copy of their pro- 
posed State school bus specifications which 
include audible alarms for emergency exit doors 
and emergency exit windows, as required by 
Standard No. 217, but do not propose to require 
audible alarms for roof exits. 

California, NSTA, and Blue Bird expressed 
support for audible alarms on emergency exit 
doors and emergency exit windows. 

The agency agrees with the comments by 
Transpec and others, that there is no safety need 
for an audible alarm on a roof exit. Unlike doors 
or windows, it is unlikely that someone could 
accidently fall out of the bus through a roof exit. 
Additionally, the requirement for such a device 
would make retrofitting of a roof exit signifi- 
cantly more difficult. For these reasons, the final 
regulatory language does not require an audible 
alarm for roof exits. 

13. Combination Roof Exits and Roof Ventilators 
Transpec, California, and Iowa commented on 
roof ventilators. Transpec stated its belief that the 
standard should include a specification for a 
"combination roof ventilator/exit," since that 
would "result in a specification that coincides 
with established industry practices." California 
stated that "revisions to the roof exit language to 
permit the use of the * * * (combination) roof 
exit/vent is strongly encouraged." Finally, 
because of the positive operational aspects of ven- 
tilation roof hatches, Iowa believed that "(a)ny 
standard that is established should not prohibit the 
ability of the emergency roof escape system to 
incorporate ventilation capability as an option." 

The agency is not aware of any language in the 
proposed standard that would have prohibited the 
use of combination roof exit/vent units. Also, the 
agency does not believe that there is any need to 



create unique specifications for such combination 
units. A combination exit vent should meet the 
same requirements as a dedicated roof emergency M 
exit. 

14. Roof E.xit Release Mechanisms 

The NPRM proposed that roof exits shall have 
"a single locking mechanism which locks and 
unlocks the roof exit with a single force applica- 
tion not greater than 40 pounds." A number of 
commenters objected to the single force applica- 
tion requirement based on safety concerns. 

Blue Bird noted that it had examined roof exit 
designs which incorporated a single force applica- 
tion device for unlatching the exit. Blue Bird 
commented that "the proposed wording would 
allow and possibly encourage roof exit latch 
design that could function like crash-bars on audi- 
torium doors. Latches that actuate by being 
pushed in the direction of the initial push-out 
motion of the exit could be knocked open 
unintentionally in a rollover accident and occu- 
pant ejection could result." 

Thomas Built also requested a roof exit release 
mechanism that is "similar to the rear push-out 
window release requirement. Namely, that the ^ 
roof exit be releasable by not more than two % 
mechanisms which do not have to be operated 
simultaneously." 

Transpec said that single force release mecha- 
nisms "should not be used in vehicles where pas- 
sengers can be thrown against them and ejected 
accidently." Accordingly, Transpec suggested a 
"double action" release mechanism for roof exits 
rather than the proposed "single action" release 
mechanism. 

Finally, Oregon expressed its belief that a dou- 
ble action latch for roof exits would be safer than 
the single action latch that was proposed. 

The agency agrees with the above comments 
and is concerned about the potential for ejection 
in a rollover if a single release mechanism is 
allowed that will allow the roof exit to open upon 
the application of force in the direction the roof 
exit opens. Accordingly, the final regulatory lan- 
guage adopts language similar to the existing 
Standard No. 217 requirements for rear push-out 
windows. Specifically, not more than two release 
mechanisms can be used. The mechanism or, if 
two mechanisms are used, each mechanism, shall ^ 
require either one or two force applications to 
open. At least one of these force applications 



PART 571; S 217— PRE-36 



must differ from the direction of the initial push- 
out motion by no less than 90 degrees and no 
more than 180 degrees. 

75. Wheelchair Lifts 

Thomas Built Buses commented that many 
school buses are equipped for wheelchair pas- 
sengers, including the installation of a wheelchair 
lift. It suggested that NHTSA "allow replacement 
of one emergency door with a wheelchair lift 
door if the bus is equipped with at least one 
wheelchair placement." 

There are two types of wheelchair lifts: passive 
and active. Passive lifts are devices which are 
normally located in an existing doorway used 
both by persons with disabilities and those with- 
out disabilities. When stowed, a passive lift 
allows persons without disabilities the unimpeded 
use of the door in which the lift is located. By 
contrast, active lifts are devices that require a 
separate opening in the bus body and which 
impede the use of that opening when stowed. 

The agency believes that doorways incorporat- 
ing active lifts should be reserved for wheelchair- 
bound or other disabled children who cannot eas- 
ily use other exits on the bus. Additionally, the 
agency notes that, if the bus driver is not avail- 
able, it may not be as easy for a child to operate 
an active lift to open the doorway, as it is for a 
child to operate other emergency exit mecha- 
nisms. Also, since active lifts take time to oper- 
ate, they may not provide a sufficiently fast 
means of emergency exit for a child without 
disabilities. 

Based on the above, the agency has concluded 
that door openings that contain a passive lift 
equipment can be used to fulfill the minimum 
emergency exit requirements. However, openings 
for active lifts cannot. 

76. Title of Standard 

The NPRM proposed to change the name of 
Standard No. 217 to reflect more accurately the 
scope and purpose of the standard. Only NSTA 
and Washington commented on the proposal, and 
both agreed with the change. Accordingly, the 
final rule establishes a new title for Standard No. 
217, Bus Emergency Exits and Window Retention 
and Release. 

17. Leadtime 
The NPRM proposed an 18-month leadtime for 
the effective date of any new school bus emer- 



gency exit requirements. Because of its concerns 
about structural fatigue from additional side emer- 
gency exit doors, Thomas Built requested a two- 
year leadtime. Blue Bird stated that the proposed 
18-month lead time is adequate "providing no 
new or unusual requirements are incorporated in 
the final rule that are significantly different from 
the proposals." Also, Blue Bird asserted that the 
agency would need "to respond to requests for 
interpretations or clarifications in a timely manner 
and to make available associated test procedures 
and references in a timely manner" if the 18- 
month leadtime is to be acceptable. 

Given the agency's conclusion that the Thomas 
Built concerns over structural fatigue due to side 
emergency exit doors are not significant (See Sec- 
tion 2, Option A, Emergency Exit Doors, or 
Option B, Doors and Roof Hatches), and the fact 
that no more than two additional side emergency 
exit doors would ever have to be installed on a 
bus, the agency has concluded that an 18-month 
leadtime is adequate. 

This final rule does not have any retroactive 
effect. Under section 103(d) of the National Traf- 
fic and Motor Vehicle Safety Act (Safety Act; 15 
U.S.C. 1392(d)), whenever a Federal motor 
vehicle safety standard is in effect, a state may 
not adopt or maintain a safety standard applicable 
to the same aspect of performance which is not 
identical to the Federal standard, except to the 
extent that the state requirement imposes a higher 
level of performance and applies only to vehicles 
procured for the State's use. Section 105 of the 
Safety Act (15 U.S.C. 1394) sets forth a proce- 
dure for judicial review of final rules establishing, 
amending or revoking Federal motor vehicle 
safety standards. That section does not require 
submission of a petition for reconsideration or 
other administrative proceedings before parties 
may file suit in court. 

(Note: For the convenience of the reader, the pre- 
amble uses U.S. units of weights and measurements 
since these units were used in the NPRM. However, 
pursuant to E.O. 12770 (56 F.R. 35801; July 29, 
1991), the agency is in the process of converting all 
safety standards to metric units. Therefore, metric 
equivalents, rounded to the nearest whole unit, are 
used in the regulatory text of this notice will be used 
throughout future Standard No. 217 notices.) 

In consideration of the foregoing, 49 CFR 
571.217 is amended as follows: 



PART 571; S 217— PRE-37 



The title of Standard No. 217, Bus Window 
Retention and Release, (49 CFR 571.217) is 
revised to read as follows: 

§571.217 Standard No. 217, Bus Emergency 
Exits and Window Retention and Release. 

Paragraph S4 of Standard No. 217 is amended 
by adding the following definitions in alphabetical 
order: 

Daylight opening means the maximum unob- 
structed opening of an emergency exit when 
viewed from a direction perpendicular to the 
plane of the opening. 

Mid-point of the passenger compartment means 
any point on a vertical transverse plane bisecting 
the vehicle longitudinal centerline that extends 
between the two vertical transverse planes which 
define the foremost and rearmost limits of the 
passenger compartment. 

Passenger compartment means space within the 
school bus interior that is between a vertical 
transverse plane located 76 centimeters in front of 
the forwardmost passenger seating reference point 
and a vertical transverse plane tangent to the rear 
interior wall of the bus at the vehicle centerline. 

Post and roof how panel space means the area 
between two adjacent post and roof bows. 

4. Paragraph S5.2.3 of Standard No. 217 is 
revised to read as follows: 

S5.2.3 School buses. Each school bus shall 
comply with S5.2.3.1 through S5.2.3.3. 

S5.2.3.1 Each bus shall be equipped with the 
exits specified in either S5.2.3.1(a) or S5. 2. 3. 1(b), 
chosen at the option of the manufacturer. The 
area in square centimeters of the unobstructed 
openings for emergency exit shall collectively 
amount to at least 170 times the number of des- 
ignated seating positions in the bus. The amount 
of emergency exit area credited to an emergency 
exit is based on the daylight opening of the exit 
opening. 

(a)(1) One rear emergency door that opens out- 
ward and is hinged on the right side (either side 
in the case of a bus with a GVWR of 4,536 kilo- 
grams or less), and exits providing an additional 
emergency exit area (AEEA) calculated in accord- 
ance with the following formula: 



AEEA = [TA - FSDA - RDEA] 

Where: ^ 

TA (total area) = 170 x number of designated seating 
positions: 

FSDA (front service door area) = size of the available 
front service door opening; and 

RDEA (rear door exit area) = size of the available rear 
emergency exit door opening. 

(2) The exits installed to provide the AEEA 
shall be of the types specified in paragraphs (a)(2) 
(i) through (iii) of this section, selected in the 
sequence specified in those paragraphs — 

(i) A left side emergency exit door that meets 
the requirements of S5. 2. 3. 2(a); 

(ii) An emergency roof exit that meets the 
requirements of S5. 2. 3.2(b); 

(iii) Any of the following types of exits, if nec- 
essary to provide the AEEA: Side emergency exit 
doors that meet the requirements of S5. 2. 3. 2(a), 
emergency roof exits that meet the requirements 
of S5. 2. 3. 2(b), or emergency window exits that 
meet the requirements of S5. 2. 3. 2(c), at the option 
of the manufacturer. 

(b)(1) One emergency door on the vehicle's left ^ 
side that is hinged on its forward side and meets ^ 
the requirements of S5. 2. 3. 2(a), and a push-out 
rear window that provides a minimum opening 
clearance 41 centimeters high and 122 centimeters 
wide and meets the requirements of S5.2.3.2(c), 
and exits providing an additional emergency exit 
area (AEEA) calculated in accordance with the 
following formula: 

AEEA=[TA— FSDA— SDEA— POWA] 

Where: 

TA (total area) = 170 x number of designated seating 
positions; 

FSDA (front service door area)=size of the available 
front service door opening; 

SDEA (side door exit area)=size of the available side 
emergency exit door opening; and 

POWA (push-out window area)=size of the available 
rear emergency push-out window opening. 

(2) The exits installed to provide the AEEA 
shall be of the types specified in paragraphs 



PART 57'.; S 217— PRE-38 



(b)(2) (i) through (iii) of this section, selected in 
"V. the sequence specified in those paragraphs — 
))) (i) A right side emergency exit door that meets 

the requirements of S5. 2. 3. 2(a); 

(ii) An emergency roof exit that meets the 
requirements of S5. 2. 3.2(b); 

(iii) Any of the following types of exits, if nec- 
essary to provide the AEEA; side emergency exit 
doors that meet the requirements of S5. 2. 3.2(a), 
emergency roof exits that meet the requirements 
of S5. 2. 3. 2(b), or emergency window exits that 
meets the requirements of S5. 2. 3. 2(c), at the 
option of the manufacturer. 

(c) The area of an opening equipped with a 
wheelchair lift is counted toward meeting the 
AEEA requirement under paragraph (a) or (b) of 
this section only if the lift is of a design which 
allows it to be folded or stowed in such a manner 
that the area is available for use by persons not 
needing the lift. The daylight opening of such an 
exit is calculated with the lift in the folded or 
stowed position. 

S5.2.3.2 All emergency exits required by 
S5.2.3.1(a) and S5.2.3.1(b) shall meet the follow- 

l\ ing criteria: 

' (a) Side emergency exit doors. 

(1) Each side emergency exit door shall be 
hinged on its forward side. 

(2) A side emergency exit door installed pursu- 
ant to S5.2.3.1(a)(2)(i) shall be located on the left 
side of the bus and as near as practicable to the 
midpoint of the passenger compartment. A single 
side emergency exit door installed pursuant to 
S5.2.3.1(a)(2)(iii) shall be located on the right 
side of the bus. In the case of a bus equipped 
with two emergency door exits pursuant to 
S5.2.3.1(a)(2)(iii), the first shall be located on the 
right side and the second on the left side of the 
bus. 

(3) A side emergency exit door installed pursu- 
ant to S5.2.3.1(b)(2)(i) shall be located on the 
right side of the bus. A single side emergency 
exit door installed pursuant to S5.2.3.1(b)(2)(iii) 
shall be located on the left side of the bus. In the 
case of a bus equipped with two emergency door 
exits pursuant to S5.2.3.1(b)(2)(iii), the first shall 
be located on the left side and the second on the 
right side of the bus. 

' (4) No two side emergency exit doors shall be 

located, in whole or in part, within the same post 
and roof bow panel space. 



(b) Ertiergency roof exit. ( 1 ) Each emergency 
roof exit shall be hinged on its forward side, and 
shall be operable from both inside and outside the 
vehicle. 

(2) In a bus equipped with a single emergency 
roof exit, the exit shall be located as near as prac- 
ticable to the midpoint of the passenger compart- 
ment. 

(3) In a bus equipped with two emergency roof 
exits, one shall be located as near as practicable 
to a point equidistant between the midpoint of the 
passenger compartment and the foremost limit of 
the passenger compartment and the other shall be 
located as near as practicable to a point equi- 
distant between the midpoint of the passenger 
compartment and the rearmost point of the pas- 
senger compartment. 

(4) In a bus equipped with three or more emer- 
gency roof exits, the roof exits shall be installed 
so that, to the extent practicable, the longitudinal 
distance between each pair of adjacent roof exits 
is the same and equal to the distance from the 
foremost point of the passenger compartment to 
the foremost roof exit and to the distance from 
the rearmost point of that compartment to the 
rearmost roof exit. 

(5) Except as provided in paragraph (b)(6) of 
this section, each emergency roof exit shall be 
installed with its longitudinal centerline coincid- 
ing with a longitudinal vertical plane passing 
through the longitudinal centerline of the school 
bus. 

(6) In a bus equipped with two or more emer- 
gency roof exits, for each roof exit offset from 
the longitudinal vertical plane specified in para- 
graph (b)(5) of this section, there shall be another 
roof exit offset from that plane an equal distance 
to the other side. 

(c) Emergency exit windows. A bus equipped 
with emergency exit windows shall have an even 
number of such windows, not counting a push-out 
rear window required by S5. 2. 3. 1(b). Any side 
emergency exit windows shall be evenly divided 
between the right and left sides of the bus. 

S5.2.3.3 The engine starting system of a bus 
shall not operate if any emergency exit is locked 
from either inside or outside the bus. For pur- 
poses of this requirement, "locked" means that 
the release mechanism cannot be activated and 
the exit opened by a person at the exit without a 
special device such as a key or special informa- 
tion such as a combination. 



PART 571; S 217— PRE-39 



5. Paragraph S5.3.3 is revised to read as fol- 
lows: 

S5.3.3 School bus emergency exit release. 

55.3.3.1 When tested under the conditions of S6, 
both before and after the window retention test 
required by S5.1, each school bus emergency exit 
door shall allow manual release of the door by a 
single person, from both inside and outside the 
passenger compartment, using a force application 
that conforms to paragraphs (a) through (c), except 
a school bus with a GVWR of 4,536 kilograms or 
less does not have to conform to paragraph (a). 
The release mechanism shall operate without the 
use of remote controls or tools, and notwithstand- 
ing any failure of the vehicle's power system. 
When the release mechanism is not in the position 
that causes an emergency exit door to be closed 
and the vehicle's ignition is in the "on" position, 
a continuous warning sound shall be audible at the 
driver's seating position and in the vicinity of that 
emergency exit door. 

(a) Location: Within the high force access 
region shown in figure 3A for a side emergency 
exit door, and in figure 3D for a rear emergency 
exit door. 

(b) Type of motion: Upward from inside the 
bus; at the discretion of the manufacturer from 
outside the bus. Buses with a GVWR of 4,536 
kilograms or less shall provide interior release 
mechanisms that operate by either an upward or 
pull-type motion. The pull-type motion shall be 
used only when the release mechanism is recessed 
in such a manner that the handle, lever, or other 
activating device, before being pulled, does not 
protrude beyond the rim of the recessed recep- 
tacle. 

(c) Magnitude of force: Not more than 178 
newtons. 

55.3.3.2 When tested under the conditions of S6., 
both before and after the window retention test 
required by S5.1, each school bus emergency exit 
window shall allow manual release of the exit by 
a single person, from inside the passenger 
compartment, using not more than two release 
mechanisms located in specified low-force or 
high-force regions (at the option of the manufac- 
turer) with force applications and types of motions 
that conform to either paragraph (a) or (b). In the 
case of windows with one release mechanism, the 



mechanism shall require two force applications to 
open. In the case of windows with two release m 
mechanisms, each mechanism shall require either ^ 
one or two force applications to open. At least one 
of these force applications for each window shall 
differ from the direction of the initial push-out 
motion of the exit by no less than 90° and no 
more than 180°. Each release mechanism shall 
operate without the use of remote controls or 
tools, and notwithstanding any failure of the 
vehicle's power system. When the release mecha- 
nism is open and the vehicle's ignition is in the 
"on" position, a continuous warning shall be 
audible at the driver's seating position and in the 
vicinity of that emergency exit. 

(a) Emergency exit windows — Low-force 
application. 

(1) Location: Within the low-force access 
regions shown in Figures 1 and 3 for an emer- 
gency exit window. 

(2) Type of motion: Rotary or straight. 

(3) Magnitude: Not more than 89 newtons. 

(b) Emergency exit windows — High-force 
application. 

(1) Location: Within the high-force access 
regions shown in Figures 2 and 3 for an emer- % 
gency exit window. 

(2) Type of motion: Straight and perpendicular 
to the undisturbed exit surface. 

(3) Magnitude: Not more than 178 newtons. 

S5.3.3.3 When tested under the conditions of S6., 
both before and after the window retention test 
required by S5.1, each school bus emergency roof 
exit shall allow manual release of the exit by a 
single person, from both inside and outside the 
passenger compartment, using not more than two 
release mechanisms located in specified low-force 
or high-force regions (at the option of the manu- 
facturer) with force applications and types of 
motions that conform to either paragraph (a) or 
(b). In the case of roof exits with one release 
mechanism, the mechanism shall require two force 
applications to open. In the case of roof exits with 
two release mechanisms, each mechanism shall 
require either one or two force applications to 
open. At least one of these force applications for 
each roof exit shall differ from the direction of the 
initial push-out motion of the exit by no less than ^ 

90° and no more than 180°. ^ 

(a) Emergency roof exits — Low-force applica- 



PART 57 i; S 217— PRE^O 



(1) Location: Within the low-force access 
regions shown in Figure 3B, in the case of buses 
whose roof exits are not offset from the plane 
specified in S5. 2. 3. 2(b)(5). In the case of buses 
which have roof exits offset from the plane speci- 
fied in S5.2.3. 2(b)(5), the amount of offset shall 
be used to recalculate the dimensions in Figure 
3B for the offset exits. 

(2) Type of motion: Rotary or straight. 

(3) Magnitude: Not more than 89 newtons. 

(b) Emergency roof exits — High-force applica- 
tion. 

(1) Location: Within the high-force access 
regions shown in Figure 3B, in the case of buses 
whose roof exits are not offset from the plane 
specified in S5. 2. 3. 2(b)(5). In the case of buses 
which have roof exits offset from the plane speci- 
fied in S5.2.3.2(b)(5), the amount of offset shall 
be used to recalculate the dimensions in Figure 
3B for the offset exits. 

(2) Type of motion: Straight and perpendicular 
to the undisturbed exit surface. 

(3) Magnitude: Not more than 178 newtons. 

6. Paragraph S5.4.2.1 is revised to read as fol- 
lows: 

S5.4.2.1 School buses with a GVWR of more than 
4,536 kilograms. 

(a) Emergency exit doors. After the release 
mechanism has been operated, each emergency 
exit door of a school bus shall, under the condi- 
tions of S6., before and after the window reten- 
tion test required by S5.1, using the force levels 
specified in S5.3.3, be manually extendable by a 
single person to a position that permits: 

(1) In the case of a rear emergency exit door, 
an opening large enough to permit unobstructed 
passage of a rectangular parallelepiped 114 centi- 
meters high, 61 centimeters wide, and 30 centi- 
meters deep, keeping the 114 centimeter dimen- 
sion vertical, the 61 centimeter dimension parallel 
to the opening, and the lower surface in contact 
with the floor of the bus at all times; and 

(2) In the case of a side emergency exit door, 
an opening at least 114 centimeters high and 61 
centimeters wide. 

(i) Except as provided in paragraph (a)(2)(ii) of 
this section, no portion of a seat or a restraining 
barrier shall be installed within the area bounded 
by the opening of a side emergency exit door, a 
vertical transverse plane tangent to the rearward 
edge of the door opening frame, a vertical trans- 



verse plane parallel to that plane at a distance of 
30 centimeters forward of that plane, and a 
longitudinal vertical plane passing through the 
longitudinal centerline of the bus. (See Figure 
5A.) 

(ii) A seat bottom may be located within the 
area described in paragraph (a)(2)(i) of this sec- 
tion if the seat bottom pivots and automatically 
assumes and retains a vertical position when not 
in use, so that no portion of the seat bottom is 
within the area described in paragraph (i) when 
the seat bottom is vertical. (See Figure 5B.) 

(iii) No portion of a seat or restraining barrier 
located forward of the area described in paragraph 
(a)(2)(i) of this section and between the door 
opening and a longitudinal vertical plane passing 
through the longitudinal centerline of the bus 
shall extend rearward of a vertical transverse 
plane tangent to the forwardmost portion of a 
latch mechanism on the door. (See Figures 5B 
and 5C.) 

(3)(i) Each emergency exit door of a school 
bus shall be equipped with a positive door open- 
ing device that, after the release mechanism has 
been operated, under the conditions of S6, before 
and after the window retention test required by 
S5.1— 

(A) Bears the weight of the door; 

(B) Keeps the door from closing past the point 
at which the door is perpendicular to the side of 
the bus body, regardless of the body's orientation; 
and 

(C) Provides a means for release or override. 

(ii) The positive door opening device shall per- 
form the functions specified in paragraphs 
(a)(3)(i) (A) and (B) of this section without the 
need for additional action beyond opening the 
door past the point at which the door is per- 
pendicular to the side of the bus body. 

(b) Emergency roof exits. After the release 
mechanism has been operated, each emergency 
roof exit of a school bus shall, under the condi- 
tions of S6, before and after the window retention 
test required by S5.1, using the force levels speci- 
fied in S5.3.3, be manually extendable by a single 
person to a position that permits an opening at 
least 41 centimeters high and 41 centimeters 
wide. 

7. Paragraph S5.5.32 is revised to read as fol- 
lows: 



PART 571; S 217— PRE^l 



S5.5.3 School bus. 

(a) Each school bus emergency exit provided in 
accordance with S5.2.3.1 shall have the designa- 
tion "Emergency Door" or "Emergency Exit," 
as appropriate, in letters at least 5 centimeters 
high, of a color that contrasts with its back- 
ground. For emergency exit doors, the designation 
shall be located at the top of, or directly above, 
the emergency exit door on both the inside and 
outside surfaces of the bus. The designation for 
roof exits shall be located on an inside surface of 
the exit, or within 30 centimeters of the roof exit 
opening. For emergency window exits, the des- 
ignation shall be located at the top of, or directly 
above, or at the bottom of the emergency window 
exit on both the inside and outside surfaces of the 
bus. 

(b) Concise operating instructions describing 
the motions necessary to unlatch and open the 
emergency exit shall be located within 15 centi- 



meters of the release mechanism on the inside 
surface of the bus. These instructions shall be in 
letters at least 1 centimeter high and of a color 
that contrasts with its background. 
Example: 

(1) Lift to Unlatch, Push to Open 

(2) Turn Handle, Push Out to Open 

(c) Each opening for a required emergency exit 
shall be outlined around its outside perimeter with 
a minimum 3 centimeters wide retroreflective 
tape, either red, white, or yellow in color, that, 
when tested under the conditions specified in S6. 1 
of 571.131, meets the criteria specified in Table 
1. 

Issued on October 27, 1992. 

Howard M. Smolkin, 
Executive Director. 

57 F.R, 49413 
November 2, 1992 



PART 571; S 217— PRE^2 



PREAMBLE TO AN AMENDMENT TO FEDERAL MOTOR VEHICLE SAFETY 

STANDARD NO. 217 

Bus Emergency Exits and Window Retention and Release 

(Docket No. 88-21 ; Notice 5) 



ACTION: Final rule; technical amendment. 

SUMMARY: This rule corrects an error made in a 
November 2, 1992, final rule amending Federal 
Motor Vehicle Safety Standard No. 217, Bus 
Emergency Exits and Window Retention and 
Release. The conversion to metric units of the for- 
mula for determining the amount of exit area 
which must be provided was incorrectly per- 
formed. In addition, a table and three figures 
referred to in the regulatory language of the final 
rule were omitted. 

EFFECTIVE DATE: The amendment made by this 
rule is effective May 2, 1994. 

SUPPLEMENTARY INFORMATION: On Novem- 
ber 2, 1992, NHTSA issued a final rule amending 
Federal Motor Vehicle Safety Standard No. 217, 
Bus Emergency Exits and Window Retention and 
Release, to revise the minimum requirements for 
school bus emergency exits, to improve access to 
school bus emergency doors, and to improve the 
visibility of school bus emergency exits. 

This notice corrects several errors in that final 
rule. First, pursuant to E.O. 12770, Metric Usage 
in Federal Government Programs (56 F.R. 35801; 
July 29, 1991), the agency is in the process of 
converting all safety standards to metric units. 
Therefore, metric equivalents, rounded to the 
nearest whole unit, were used in the regulatory 
test of the final rule. However, the formula for 
determining the amount of exit area which must 
be provided was incorrectly converted. The notice 
of proposed rulemaking preceding the recent final 
rule proposed to require that school buses provide 
minimum emergency exit spaces which together 
are equal, in square inches, to 67 times the num- 
ber of seating positions. This formula was erro- 
neously converted in the final rule to centimeters, 
not square centimeters. The final rule should have 
specified that school buses are required to provide 
minimum emergency exit spaces which together 



are equal in square centimeters, to 432 times the 
number of seating position, not 170 times the 
number of seating positions. (Note: A notice of 
proposed rulemaking published the same day as 
the final rule also erroneously used the latter fig- 
ure (57 FR 49444). If a final rule is issued based 
on that notice, the correct figure will be used.) 

Second, as part of the final rule, S5.4.2. 1(a)(2) 
was amended to specify a zone which must be 
kept clear to provide access to a side emergency 
door. The regulatory language refers to three fig- 
ures. Figure 5A, Figure 5B, and Figure 5C, which 
illustrate these requirements. These figures were 
omitted from the copies of the final rule sent to 
the Federal Register. The final rule also amended 
S5.5.3(c) to require marking of emergency exits 
with retroreflective tape which meets intensity cri- 
teria specified in Table 1. Table 1 was also omit- 
ted from the final rule. 

This correction imposes no duties or respon- 
sibilities on any party not already imposed by the 
final rule. Discussion in the preamble to the final 
rule makes it clear that the agency did not intend 
to change the formula and that the error was 
merely a conversion error. The figures and table 
clarify obligations imposed by the final rule. 
Accordingly, NHTSA finds for good cause that 
notice and opportunity for comments are nec- 
essary. 

In consideration of the foregoing, 49 CFR 
S571.217 is amended as follows: 

1. Paragraph S5.2.3.1 of Standard No. 217 is 
revised to read as follows: 

S5.2.3.1 Each bus shall be equipped with the exits 
specified in either §5.2.3. 1(a) or § 5.2.3.1(b), cho- 
sen at the option of the manufacturer. The area in 
square centimeters of the unobstructed openings 
for emergency exits shall collectively amount to at 
least 432 times the number of designated seating 
positions in the bus. The amount of emergency 



PART 571: S 217— PRE^3 



exit area credited to an emergency exit is based on 
the daylight opening of the exit opening. 

(a)(1) One rear emergency door that opens out- 
ward and is hinged on the right side (either side 
in the case of a bus with a GVWR of 4.536 kilo- 
grams or less), and exits providing an additional 
emergency exit area (AEEA) calculated in accord- 
ance with the following formula: 
AEEA=[TA-FSDA-RDEA] 

Where: 

TA (total area)=432 x number of designated 
seating positions; 

FSDA (front service door area)=size of the 
available front service door opening; and 

RDEA (rear door exit area)=size of the avail- 
able rear emergency exit door opening. 

(2) The exits installed to provide the AEEA 
shall be of the types specified in paragraphs (i) 
through (iii) of this section, selected in the 
sequence specified in those paragraphs — 

(i) A left side emergency exit door that 
meets the requirements of S5. 2. 3. 2(a); 

(ii) An emergency roof exit that meets the 
requirements of S5. 2. 3.2(b); 

(iii) Any of the following types of exits, if 
necessary to provide the AEEA: Side emer- 
gency exit doors that meet the requirements of 
S5.2.3.2(a), emergency roof exits that meet the 
requirements of S5. 2. 3.2(b), or emergency win- 
dow exits that meet the requirements of 
S5.2.3.2(c), at the option of the manufacturer. 
(b)(1) One emergency door on the vehicle's left 
side that is hinged on its forward side and meets 
the requirements of S5. 2. 3. 2(a), and a push-out 
rear window that provides a minimum opening 
clearance 41 centimeters high and 122 centimeters 
wide and meets the requirements of S5. 2. 3.2(c), 
and exits providing an additional emergency exit 
area (AEEA) calculated in accordance with the 
following formula: 

AEEA=(TA-FSDA-SDEA-POWA) 



Where: 

TA (total area)=432 x number of designated , 
seating positions; C 

FSDA (front service door area)=size of the 
available front service door opening; 

SDEA (side door exit area)=size of the avail- 
able side emergency exit door opening; and 

POWA (push-out window area)=size of the 
available rear emergency push-out window 
opening. 

(2) These exits installed to provide the 
AEEA shall be of the types specified in para- 
graphs (i) through (iii) of this section, selected in 
the sequence specified in those paragraphs — 

(i) A right side emergency exit door that 
meets the requirements of § 5.2.3.2(a); 

(ii) An emergency roof exit that meets the 
requirements of S5. 2. 3. 2(b); 

(iii) Any of the following types of exits, if 
necessary to provide the AEEA: Side emer- 
gency exit doors that meet the requirements of 
S5. 2. 3. 2(a), emergency roof exits that meet the 
requirements of S5. 2. 3. 2(b), or emergency win- 
dow exits that meet the requirements of 
S5. 2. 3. 2(c), at the option of the manufacturer. ^ 

(c) The area of an opening equipped with a 
wheelchair lift is counted toward meeting the 
AEEA requirement under paragraph (a) or (b) of 
this section only if the lift is of a design that 
allows it to be folded or stowed in such a manner 
that the area is available for use by persons not 
needing the lift. The daylight opening of such an 
exit is calculated with the lift in the folder or 
stowed position. 

2. New Figures 5A, 5B, and 5C are added, to 
appear following Figure 4 at the end of S571.217, 
as follows: 

3. New Table 1 is added, to appear following 
Figure 5C at the end of S571.217, as follows: 

Issued on: November 24, 1992. 



J) 



Front 



Sides of Bus Body 



/ 



Side Emergency 
Exit Door 




D 



I 



30 cm 
Minimum 



Centerllne of Bus 



Figure 5A 



V 



PART 571; S 217— PRE-45 




Figure 5B 




Figure 5C 



i 



PART 571; S 217— PRE-46 



Table 1. Minimum Specific Intensity Per Unit Area (SIA) 

(Candelas per Footcandle Per Square Foot) 
Type III Retroreflective Material 

A— Glass Bead Retroreflective Element Material 



Observation Angle (°) 


Entrance Angle (°) 


White 


Red 


Yellow 


0.2 
0,2 
0.5 
0.5 




-4 
+30 

-4 
+30 


250 
150 
95 
65 


45 
25 
15 
10 


170 
100 
62 
45 


B— Prismatic Retroreflective Element Material 


Observation 


Angle n 


Entrance Angle (°) 


White 


Red 


Yellow 


0.2 
0.2 
0.5 
0.5 




-4 
+30 

-4 
+30 


250 
95 

200 
65 


45 
13.3 
28 
10 


170 
64 
136 

45 



Marion C. Blakey, 
Administrator 

57 F.R. 57020 
December 2, 1992 



PART 571: S 217— PRE^7 



MOTOR VEHICLE SAFETY STANDARD NO. 217 

Bus Window Retention and Release 
[Bus Emergency Exits and Window Retention and Release]* 



51. Scope. This standard establishes require- 
ments for the retention of windows other than 
windshields in buses, and establishes operating 
forces, opening dimensions, and markings for 
push-out bus windows and other emergency exits. 

52. Purpose. The purpose of this standard is to 
minimize the likelihood of occupants being 
thrown from the bus and to provide a means of 
readily accessible emergency egress. 

53. Application. This standard applies to buses, 
except buses manufactured for the purpose of 
transporting persons under physical restraint. 

54. Definitions. 

Adjacent seat means a designated seating posi- 
tion located so that some portion of its occupant 
space is not more than 10 inches from an emer- 
gency exit, for a distance of at least 15 inches 
measured horizontally and parallel to the exist. 

[Daylight opening means the maximum unob- 
structed opening of an emergency exit when 
viewed from a direction perpendicular to the 
plane of the opening.'\ 

[Mid-point of the passenger compartment 
means any point on a vertical transverse plane 
bisecting the vehicle longitudinal centerline that 
extends between the two vertical transverse 
planes which define the foremost and rearmost 
limits of the passenger compartment.^ 

Occupant space means the space directly above 
the seat and footwell, bounded vertically by the 
ceiling and horizontally by the normally posi- 
tioned seat back and the nearest obstruction of 
occupant motion in the direction the seat faces. 

[Passenger compartment means space within 
the school bus interior that is between a vertical 
transverse plane located 76 centimeters in front 
of the forn'ardmost passenger seating reference 
point and a vertical transverse plane tangent to 
the rear interior wall of the bus at the vertical 
centerline.} 



[Post and roof bow panel space means the 
area between tn'o adjacent post and roof bows.} 

Push-out window means a vehicle window 
designed to open outward to provide for emer- 
gency egress. [(57 F.R. 49413 — November 2, 
1992 Effective: May 2, 1994] 

S5. Requirements. 



S5.1 Window retention. Except as provided in 
S5.1.2, each piece of window glazing and each 
surrounding window frame, when tested in accord- 
ance with the procedure in S5.1.1 under the condi- 
tions of S6.1 through S6.3, shall be retained by its 
surrounding structure in a manner that prevents 
the formation of any opening large enough to 
admit the passage of a 4-inch diameter sphere 
under a force, including the weight of the sphere, 
of 5 pounds until any one of the following events 
occurs: 

(a) A force of 1200 pounds is reached. 

(b) At least 80% of the glazing thickness has 
developed cracks running from the load contact 
region to the periphery at two or more points, or 
shattering of the glazing occurs. 

(c) The inner surface of the glazing at the cen- 
ter of force application has moved relative to the 
window frame along a line perpendicular to the 
undisturbed inner surface, a distance equal to one- 
half of the square root of the minimum surface 
dimension measured through the center of the 
area of the entire sheet of window glazing. 

55.1.1 An increasing force shall be applied to the 
window glazing through the head form specified 
in Figure 4, outward and perpendicular to the 
undisturbed inside surface at the center of the area 
of each sheet of window glazing, with a head form 
travel of 2 inches per minute. 

55.1.2 The requirements of this standard do not 
apply to a window whose minimum surface 



[Effective: May 2, 1994] 



PART 571 



dimension measured througii the center of its area 
is less tiian 8 inches. 

S5.2 Provision of emergency exits. Buses 
other than school buses shall provide unobstructed 
openings for emergency exit which collectively 
amount, in total square inches, to at least 67 times 
the number of designated seating positions on the 
bus. At least 40 percent of the total required area 
of unobstructed openings, computed in the above 
manner, shall be provided on each side of a bus. 
However, in determining the total unobstructed 
openings provided by a bus, no emergency exit, 
regardless of its area, shall be credited with more 
than 536 square inches of the total area require- 
ment. School buses shall provide openings for 
emergency exits that confomi to S5.2.3. 

55.2.1 Buses witii a GVWR of more than 
10,000 pounds. Except as provided in S5.2.1.1, 
buses with a GVWR of more than 10,000 pounds 
shall meet the unobstructed openings requirements 
by providing side exits and at least one rear exit 
that conforms to S5.3 through S5.5. The rear exit 
shall meet the requirements when the bus is 
upright and when the bus is overturned on either 
side, with the occupant standing facing the exit. 
When the bus configuration precludes installation 
of an accessible rear exit, a roof exit that meets 
the requirements of S5.3 through S5.5 when the 
bus is overturned on either side, with the occupant 
standing facing the exit, shall be provided in the 
rear half of the bus. 

S5.2.1.1 A bus with GVWR of more than 10,000 
pounds may satisfy the unobstructed openings 
requirement by providing at least one side door for 
each three passenger seating positions in the 
vehicle. 

55.2.2 Buses with a GVWR of 10,000 pounds 
or less. Buses with a GVWR of 10.000 pounds 
or less may meet the unobstructed openings 
requirement by providing: 

(a) Devices that meet the requirements of S5.3 
through S5.5 without using remote controls or 
central power systems; 

(b) Windows that can be opened manually to a 
position that provides an opening large enough to 
admit unobstructed passage, keeping a major axis 
horizontal at all times, of an ellipsoid generated 
by rotating about its minor axis an ellipse having 



a major axis of 20 inches and a minor axis of 13 
inches; or 

(c) Doors. ^ 

S5.2.3 School buses. 

S5.2.3.1 l_Each bus shall be equipped with the 
exits specified in either §5.2.3. 1(a) or §5.2.3. 1(b), 
chosen at the option of the manufacturer. The 
area in square centimeters of the unobstructed 
openings for emergency exit shall collectively 
amount to at least 432 times the number of des- 
ignated seating positions in the bus. The amount 
of emergency exit area credited to an emergency 
exit is based on the daylight opening of the exit 
opening. 

(a)(1) One rear emergency door that opens 
outn'ard and is hinged on the right side (either 
side in the case of a bus with a GVWR of 4.536 
kilograms or less), and exits providing an addi- 
tional emergency exit area (AEEA) calculated in 
accordance with the following formula: 
AEER=[TA-FSDA-RDEA] 

Where: 

TA (total area)=432 x number of designated 
seating positions: ^ 

FSDA (front service door area)=size of the ^ 
available front service door opening: and 

RDEA (rear door exit area)=size of the 

available rear emergency exit door opening. 

(2)The exits installed to provide the AEEA 

shall be of the types specified in paragraphs (i) 

through (Hi) of this section, selected in the 

sequence specified in those paragraphs — 

(i)A left side emergency exit door that meets 
the requirements of §5. 2. 3. 2(a): 

(ii) An emergency roof e.xit that meets the 
requirements of §5. 2. 3. 2(b): 

(Hi) Any of the following types of exits, if 
necessary to provide the AEEA: Side emer- 
gency exit doors that meet the requirements of 
§ 5.2.3.2(a), emergency roof exits that meet the 
requirements of §5. 2. 3. 2(b), or emergency win- 
dow exits that meet the requirements of 
§ 5.2.3.2(c), at the option of the manufacturer. 
(b)(1) One emergency door on the vehicle's left 
side that is hinged on its forward side and meets 
the requirements of §5.2.3.2(a), and a push-out 
rear window that provides a minimum opening A 
clearance 41 centimeters high and 122 centi- W 
meters wide and meets the requirements of 



Rev. 11/2/92 



PART 571; S 217-2 



§ 5.2.3.2(c). and exits providing an additional 
emergency exit area (AREA) calculated in 
J accordance with the following formula: 
AEEA=(TA-FSDA-SDEA-POWA) 

Where: 

TA (total area)=432 x number of designated 
seating positions; 

FSDA (fi-ont service door area)-size of the 
available font serxice door opening; 

SDEA (side door exit area)=size of the avail- 
able side emergency exit door opening; and 

POWA (push-out window area)=size of the 
available rear emergency push-out window 
opening. 

(2) The exits installed to provide the AEEA 
shall be of the types specified in paragraphs (i) 
through (Hi) of this section, selected in the 
sequence specified in those paragraphs — 

(i) A right side emergency exit door that 
meets the requirements of §5. 2. 3. 2(a); 

(ii) An emergency roof exit that meets the 
requirements of § 5.2.3.2(b); 

(Hi) Any of the following types of exits, if 
\ necessary to provide the AEEA: Side emer- 

gency exit doors that meet the requirements of 
§ 5.2.3.2(a), emergency roof exits that meet the 
requirements of §5. 2. 3. 2(b). or emergency win- 
dow exits that meet the requirements of 
§ 5.2.3.2(c), at the option of the manufacturer. 

(c) The area of an opening equipped with a 
wheelchair lift is counted toward meeting the 
AEEA requirement under paragraph (a) or (b) of 
this section only if the lift is of a design that 
allows it to be folded or stowed in such a manner 
that the area is available for use by persons not 
needing the lift. The daylight opening of such an 
exit is calculated with the lift in the folder or 
stowed position. (57 F.R. 57020 — December 2, 
1992, Effective: May 2, 1994)] 

S5.2.3.2 The engine starting system of a school 
bus shall not operate if any emergency door is 
locked from either inside or outside the bus. For 
purposes of this requirement, "locked" means 
that the release mechanism cannot be activated by 
a person at the door without a special device such 
\ as a key or special information such as a combina- 
tion. 



S5.3 Emergency exit release. 

55.3.1 Each push-out window or other emergency 
exit not required by S5.2.3 shall be releasable by 
operating one or two mechanisms located within 
the regions specified in Figures 1, 2, and 3. The 
lower edge of the region in Figure 1 and Region 
B in Figure 2, shall be located 5 inches above the 
adjacent seat, or 2 inches above the armrest, if 
any, whichever is higher. 

55.3.2 When tested under the conditions of S6, 
both before and after the window retention test 
required by S5.1, each emergency exit not 
required by S5.2.3 shall allow manual release of 
the exit by a single occupant using force applica- 
tions each of which conforms, at the option of the 
manufacturer, either to (a) or (b). The release 
mechanism or mechanisms shall require for 
release one or two force applications, at least one 
of which differs by 90 to 180° from the direction 
of the initial push-out motion of the emergency 
exit (outward and perpendicular to the exit sur- 
face). 

(a) Low-force application. 

Location: As shown in Figure 1 or Figure 3. 
Type of Motion: Rotary or straight. 
Magnitude: Not more than 20 pounds. 

(b) High force application. 

Location; As shown in Figure 2 or Figure 3. 
Type of Motion: Straight, perpendicular to the 
undisturbed exit surface. 

Magnitude: Not more than 60 pounds. 

55.3.3 When tested under the conditions of S6, 
both before and after the window retention test 
required by S5.1, each school bus emergency door 
shall allow manual release of the door by a single 
person, from both inside and outside the bus pas- 
senger compartment, using a force application that 
conforms to paragraphs (a) through (c) except a 
school bus with a GVWR of 10,000 pounds or 
less does not have to conform to paragraph (a). 
Each release mechanism shall operate without the 
use of remote controls or tools, and notwithstand- 
ing any failure of the vehicle's power system. 
When the release mechanism is not in the closed 
position and the vehicle ignition is in the "on" 
position, a continuous warning sound shall be 
audible at the driver's seating position and in the 



PART 571; S 217-3 



(Rev. 11/2/92) 



vicinity of the emergency door having the 
unclosed mechanism. 

(a) Location: Within the high force access 
region shown in Figure 3A for a side emergency 
door, and in Figure 3D for a rear emergency door. 

(b) Type of motion: Upward from inside the 
bus; at the discretion of the manufacturer from 
outside the bus. Buses with a GVWR of 10,000 
pounds or less shall provide interior release 
mechanisms that operate by either an upward or 
pull-type motion. The pull-type motion shall be 
used only when the release mechanism is recessed 
in such a manner that the handle, lever, or other 
activating device does not protrude beyond the 
rim of the recessed receptacle. 

(c) Magnitude of force: Not more than 40 
pounds. 

The present S5.4 is renumbered S5.4.1, and the 
phrase "Each push-out window or other emer- 
gency exit shall, after the release mechanism has 
been operated," is replaced by the phrase "After 
the release mechanism has been operated, each 
push-out window or other emergency exit not 
required by S5.2.3," at the beginning of the para- 
graph. 

l_S5.2.3 School buses. Each school bus shall com- 
ply with S5.2.3.1 through S5.2.3.3. 

S5.2.3.1 Each bus shall be equipped with the 
exists specified in either S5.2.3.1(a) or 
S5. 2.3. lib), chosen at the option of the manufac- 
turer. The area in square centimeters of the unob- 
structed openings for emergency exit shall collec- 
tively amount to at least 170 times the number of 
designated seating positions in the bus. The 
amount of emergency exit area credited to an 
emergency exit is based on the daylight opening 
of the exit opening. 

(a)(1) One rear emergency door that opens 
outward and is hinged on the right side (either 
side in the case of a bus with a GVWR of 4,536 
kilograms or less), and exits providing an addi- 
tional emergency exit area (AEEA) calculated in 
accordance with the following formula: 
AEEA=[TA - FSDA - RDEA] 
Where: 

TA (total area) - 170 x number of designated 
seating positions; 

FSDA (front service door area) = size of the 
available front service door opening; and 
RDEA (rear door exit area) = size of the avail- 
able rear emergency exit door opening. 



(2) The exits installed to provide the AEEA 
shall be of the types specified in paragraphs 
(a)(2) (i) through (Hi) of this section, selected in ^ 
the sequence specified in those paragraphs — 

(i) A left side emergency exit door that meets 
the requirements of S5. 2. 3. 2(a): 

(ii) An emergency roof exit that meets the 
requirements of S5. 2. 3. 2(b); 

(Hi) Any of the following types of exits, if nec- 
essary to provide the AEEA: Side emergency exit 
doors that meet the requirements of S5.2.3.2(a), 
emergency roof exits that meet the requirements 
of S5.2.3.2(b), or emergency window exits that 
meet the requirements of S5.2.3.2(c), at the option 
of the manufacturer. 

(b)(1) One emergency door on the vehicle's left 
side that is hinged on its forn'ard side and meets 
the requirements of S5.2.3.2(a), and a push-out 
rear window that provides a minimum opening 
clearance 41 centimeters high and 122 centi- 
meters wide and meets the requirements of 
S5.2.3.2(c), and exits providing an additional 
emergency exit area (AEEA) calculated in 
accordance with the following formula: 

AEEA=[TA - FSDA - SDEA - POWA] - 

Where: K 

TA (total area) = 170 x number of designated 
seating positions; 

FSDA (front sen'ice door area)=size of the 
available front sen'ice door opening; 

SDEA (side door exit area)=size of the avail- 
able side emergency exit door opening; and 

POWA (push-out window area)=size of the 
available rear emergency push-out window open- 
ing. 

(2) The exits installed to provide the AEEA 
shall be of the types specified in paragraphs 
(b)(2) (i) through (Hi) of this section, selected in 
the sequence specified in those paragraphs — 

(i) A right side emergency exit door that meets 
the requirements of S5. 2.3. 2(a); 

(ii) An emergency roof exit that meets the 
requirements of S5 .2 .3 .2(b) ; 

(Hi) Any of the following types of exits, if nec- 
essary to provide the AEEA: side emergency exit 
doors that meet the requirements of S5.2.3.2(a), 
emergency roof exits that meet the requirements 
of S5.2.3.2(b), or emergency window exits that dL 
meets the requirements of S5.2.3.2(c), at the ^ 
option of the manufacturer. 



(Rev. 11/2/92) 



PART 571: S 217-4 



(c) The area of an opening equipped with a 
wheelchair lift is counted toward meeting the 
AEEA requirement under paragraph (a) or (b) of 
this section only if the lift is of a design which 
allows it to be folded or stowed in such a manner 
that the area is available for use by persons not 
needing the lift. The daylight opening of such an 
exit is calculated with the lift in the folded or 
stowed position. 

S5.2.3.2 All emergency exits required by 
S5.2.3.1(a) and S5.2.3.J(b) shall meet the follow- 
ing criteria: 

(a) Side emergency exit doors. 

(1) Each side emergency exit door shall he 
hinged on its forward side. 

(2) A side emergency exit door installed pursu- 
ant to S5.2.3.1(a)(2)(i) shall be located on the left 
side of the bus and as near as practicable to the 
midpoint of the passenger compartment. A single 
side emergency exit door installed pursuant to 
S5.2.3.](a)(2)(iii) shall be located on the right 
side of the bus. In the case of a bus equipped 
with two emergency door exits pursuant to 
S5.2.3.1(a)(2)(iii), the first shall be located on the 
right side and the second on the left side of the 
bus. 

(3) A side emergency exit door installed pursu- 
ant to S5.2.3.](b)(2)(i) shall be located on the 
right side of the bus. A single side emergency exit 
door installed pursuant to S5.2.3.1(b)(2)(iii) shall 
be located on the left side of the bus. In the case 
of a bus equipped with two emergency door exits 
pursuant to S5.2.3.1(b)(2)(iii). the first shall be 
located on the left side and the second on the 
right side of the bus. 

(4) No two side emergency exit doors shall be 
located, in whole or in part, within the same post 
and roof bow panel space. 

(b) Emergency roof exit. (I) Each emergency 
roof exit shall be hinged on its forward side, and 
shall be operable from both inside and outside 
the vehicle. 

(2) In a bus equipped with a single emergency 
roof exit, the exit shall be located as near as 
practicable to the midpoint of the passenger 
compartment. 

(3) In a bus equipped with mo emergency roof 
exits, one shall be located as near as practicable 
to a point equidistant between the midpoint of the 
passenger compartment and the foremost limit of 
the passenger compartment and the other shall be 



located as near as practicable to a point equi- 
distant between the midpoint of the passenger 
compartment and the rearmost point of the pas- 
senger compartment. 

(4) In a bus equipped with three or more emer- 
gency roof exits, the roof exits shall be installed 
so that, to the extent practicable, the longitudinal 
distance between each pair of adjacent roof exits 
is the same and equal to the distance from the 
foremost point of the passenger compartment to 
the foremost roof exit and to the distance from 
the rearmost point of that compartment to the 
rearmost roof exit. 

(5) Except as provided in paragraph (b)(6) of 
this section, each emergency roof exit shall be 
installed with its longitudinal centerline coincid- 
ing with a longitudinal vertical plane passing 
through the longitudinal centerline of the school 
bus. 

(6) In a bus equipped with mo or more emer- 
gency roof e.xits. for each roof exit offset from the 
longitudinal vertical plane specified in paragraph 
(b)(5) of this section, there shall be another roof 
exit offset from that plane an equal distance to 
the other side. 

(c) Emergency exit windows. A bus equipped 
with emergency exit windows shall have an even 
number of such windows, not counting a push-out 
rear window required by S5.2.3.1(b). Any side 
emergency exit windows shall be evenly divided 
between the right and left sides of the bus. 

S5.2.3.3 The engine starting system of a bus shall 
not operate if any emergency exit is locked from 
either inside or outside the bus. For purposes of 
this requirement, "locked" means that the release 
mechanism cannot be activated and the exit 
opened by a person at the exit without a special 
device such as a key or special information such 
as a combination. (57 F.R. 49413-November 2, 
1992. Effective: May 2, 1994.)] 

[S5.3.3 School bus emergency exit release. 

S5.3.3.1 When tested under the conditions of S6., 
both before and after the window retention test 
required by S5.I, each school bus emergency exit 
door shall allow manual release of the door by a 
single person, from both inside and outside the 
passenger compartment, using a force application 
that conforms to paragraphs (a) through (c). 
except a school bus with a GVWR of 4.536 kilo- 



PART571; S 217-5 



(Rev. 11/2/92) 



grams or less does not have to conform to para- 
graph (a). The release mechanism shall operate 
without the use of remote controls or tools, and 
notwithstanding any failure of the vehicle's power 
system. When the release mechanism is not in the 
position that causes an emergency exit door to be 
closed and the vehicle's ignition is in the "on" 
position, a continuous warning sound shall be 
audible at the driver's seating position and in the 
vicinity of that emergency exit door. 

(a) Location: Within the high force access 
region shown in Figure 3 A for a side emergency 
exit door, and in figure 3D for a rear emergency 
exit door. 

(b) Type of motion: Upward from inside the 
bus; at the discretion of the manufacturer from 
outside the bus. Buses with a GVWR of 4,536 
kilograms or less shall provide interior release 
mechanisms that operate by either an upward or 
pull-type motion. The pull-type motion shall be 
used only when the release mechanism is recessed 
in such a manner that the handle, lever, or other 
activating device, before being pulled, does not 
protrude beyond the rim of the recessed recep- 
tacle. 

(c) Magnitude of force: Not more than 178 
newtons. 

S5.3.3.2 When tested under the conditions of S6.. 
both before and after the window retention test 
required by 55.7, each school bus emergency exit 
window shall allow manual release of the exit by 
a single person, from inside the passenger 
compartment, using not more than two release 
mechanisms located in specified low-force or 
high-force regions (at the option of the manufac- 
turer) with force applications and types of motions 
that conform to either paragraph (a) or (b). In the 
case of windows with one release mechanism, the 
mechanism shall require two force applications to 
open. In the case of windows with two release 
mechanisms, each mechanism shall require either 
one or two force applications to open, at least one 
of these force applications for each window shall 
dijfer from the direction of the initial push-out 
motion of the exit by no less than 90° and no more 
than 180°. Each release mechanism shall operate 
without the use of remote controls or tools, and 
not withstanding any failure of the vehicle's power 
system. When the release mechanism is open and 
the vehicle's ignition is in the "on" position, a 
continuous warning shall be audible at the driv- 



er's seating position and in the vicinity of that 
emergency exit. 

(a) Emergency exit windows — Low-force 
application. ^^ 

(1) Location: Within the low-force access 
regions shown in Figures 1 and 3 for an emer- 
gency exit window. 

(2) Type of motion: Rotaiy or straight. 

(3) Magnitude: Not more than 89 newtons. 

(b) Emergency exit windows — High-force 
application. 

(1) Location: Within the high-force access 
regions shown in Figures 2 and 3 for an emer- 
gency exit window. 

(2) Type of motion: Straight and perpendicular 
to the undisturbed exit surface. 

(3) Magnitude: Not more than 178 newtons. 

S5.3.3.3 When tested under the conditions of S6., 
both before and after the window retention test 
required by 55.7, each school bus emergency roof 
exit shall allow manual release of the exit by a 
single person, from both inside and outside the 
passenger compartment, using not more than two 
release mechanisms located in specified low-force 
or high-force regions (at the option of the manu- 
facturer) with force applications and types of ^ 
motions that conform to either paragraph (a) or 
(b). In the case of roof exits with one release 
mechanism, the mechanism shall require two force 
applications to open. In the case of roof exits with 
n\'o release mechanisms, each mechanism shall 
require either one or tn>o force applications to 
open. At least one of these force applications for 
each roof exit shall dijfer from the direction of the 
initial push-out motion of the exit by no less than 
90° and no more than 180°. 

(a) Emergency roof exits — Low-force applica- 
tion. 

(1) Location: Within the low force access 
regions shown in Figure 3B, in the case of buses 
whose roof exits are not offset from the plane 
specified in S5. 2. 3. 2(b)(5). In the case of buses 
which have roof exits offset from the plane speci- 
fied in S5. 2. 3. 2(b)(5), the amount of offset shall 
be used to recalculate the dimensions in Figure 
38 for the offset exits. 

(2) Type of motion: Rotary or straight. 

(3) Magnitude: Not more than 89 newtons. 

(b) Emergency roof exits — High-force applica- ^ 
tion. 



(Rev. 11/2/92) 



PART 571; S 217-6 



(1) Location: Within the high force access 
regions shown in Figure SB, in the case of buses 

"\ whose roof exits are not offset from the plane 
) specified in S5.2.3.2(b)(5). In the case of buses 
which have roof exits offset from the plane speci- 
fied in S5.2.3.2(b)(5), the amount of offset shall 
be used to recalculate the dimensions in Figure 
3B for the offset exits. 

(2) Type of motion: Straight and perpendicular 
to the undisturbed exit surface. 

(3) Magnitude: Not more than 178 newtons. 
(57 FR 49413— November 2, 1992. Effective: 
May 2, 1994] 

S5.4 Emergency exit extension. 

55.4.1 After the release mechanism has been oper- 
ated, each push-out window or other emergency 
exit not required by S5.2.3 shall, under the condi- 
tions of S6, before and after the window retention 
test required by S5.1, using the reach distances 
and corresponding force levels specified in S5.3.2, 
be manually extendable by a single occupant to a 
position that provides an opening large enough to 
admit unobstructed passage, keeping a major axis 

^ horizontal at all times, of an ellipsoid generated by 
rotating about its minor axis an ellipse having a 
major axis of 20 inches and a minor axis of 13 
inches. 

55.4.2 School bus emergency exit extension. 

S5.4.2.1 School bus with a GVWR of more 
than 10,000 pounds. After the release mechanism 
has been operated, the emergency door of a school 
bus with a GVWR of more than 10,000 pounds 
shall, under the conditions of S6, before and after 
the window retention test required by S5.1, using 
the force levels specified in S5.3.3, be manually 
extendable by a single person to a position that 
permits — 

(a) In the case of rear emergency door, an 
opening large enough to permit unobstructed pas- 
sage of a rectangular parallelepiped 45 inches 
high, 24 inches wide, and 12 inches deep, keeping 
the 45-inch dimension vertical, the 24-inch 
dimension parallel to the opening, and the lower 
surface in contact with the floor of the bus at all 
times; and 

)(b) In the case of a side emergency door, an 
opening at least 45 inches high and 24 inches 
wide. A vertical transverse plane tangent to the 



rearmost point of a seat back shall pass through 
the forward edge of a side emergency door. 

[S5.4.2.1 School buses with a GVWR of more 
than 4,536 kilograms. 

(a) Emergency exit doors. After the release 
mechanism has been operated, each emergency 
exit door of a school bus shall, under the condi- 
tions of S6., before and after the window reten- 
tion test required by S5.1, using the force levels 
specified in S5.3.3, be manually extendable by a 
single person to a position that permits: 

(1) In the case of a rear emergency exit door, 
an opening large enough to permit unobstructed 
passage of a rectangular parallelepiped 114 
centimeters high, 61 centimeters wide, and 30 
centimeters deep, keeping the 114 centimeter 
dimension vertical, the 61 centimeter dimension 
parallel to the opening, and the lower surface in 
contact with the floor of the bus at all times; and 

(2) In the case of a side emergency exit door, 
an opening at least 114 centimeters high and 61 
centimeters wide. 

(i) Except as provided in paragraph (a)(2)(ii) 
of this section, no portion of a seat or a restrain- 
ing barrier shall be installed within the area 
bounded by the opening of a side emergency exit 
door, a vertical transverse plane tangent to the 
reai-H'ard edge of the door opening frame, a verti- 
cal transverse plane parallel to that plane at a 
distance of 30 centimeters fo)-ward of that plane, 
and a longitudinal vertical plane passing through 
the longitudinal centerline of the bus. (See Figure 
5 A). 

(ii) A seat bottom may be located within the 
area described in paragraph (a)(2)(i) of this sec- 
tion if the seat bottom pivots and automatically 
assumes and retains a vertical position when not 
in use. so that no portion of the seat bottom is 
within the area described in paragraph (i) when 
the seat bottom is vertical. (See Figure 58). 

(Hi) No portion of a seat or restraining barrier 
located forward of the area described in para- 
graph (a)(2)(i) of this section and between the 
door opening and a longitudinal vertical plane 
passing through the longitudinal centerline of the 
bus shall extend rearwai'd of a vertical transverse 
plane tangent to the foiwardmost portion of a 
latch mechanism on the door. (See Figures 58 
and5C.) 

(3)(i) Each emergency exit door of a school 
bus shall be equipped with a positive door open- 



P ART 571; S 217-7 



(Rev. 11/2/92) 



ing device that, after the release mechanism has 
been operated, under the conditions of S6, before 
and after the window retention test required by 
55.7— 

(A) Bears the weight of the door; 

(B) Keeps the door from closing past the point 
at which the door is perpendicular to the side of 
the bus body, regardless of the body's orienta- 
tion; and 

(C) Provides a means for release or override. 

(ii) The positive door opening device shall per- 
form the functions specified in paragraph (a)(3)(i) 
(A) and (B) of this section without the need for 
additional action beyond opening the door past 
the point at which the door is perpendicular to 
the side of the bus body. 

(b) Emergency roof exits. After the release 
mechanism has been operated, each emergency 
roof exit of a school bus shall, under the condi- 
tions of S6, before and after the window retention 
test required by S5.1 , using the force levels speci- 
fied in S5.3.3, be manually extendable by a single 
person to a position that permits an opening at 
least 41 centimeters high and 41 centimeters 
wide. (57 FR 49413— November 2, 1992. Effec- 
tive: May 2, 1994)] 

S5.4.2.2 School buses less than 10,000 
pounds. A school bus with a GVWR of 10,000 
pounds or less shall conform to all the provisions 
of S5.4.2 except that the parallelepiped dimension 
for the opening of the rear emergency door or 
doors shall be 45 inches high, 22 inches wide, and 
6 inches deep. 

S5.5 Emergency exit Identification. 

S5.5.1 In buses other than school buses, except for 
windows serving as emergency exits in accord- 
ance with S5.2.2(b) and doors in buses with a 
GVWR of 10,000 pounds or less, each emergency 
door shall have the designation "Emergency 
Door" or "Emergency Exit" and each push-out 
window or other emergency exit shall have the 
designation "Emergency Exit" followed by con- 
cise operating instructions describing each motion 



necessary to unlatch and open the exit, located 
within 6 inches of the release mechanism. 

Examples: ^ 

( 1 ) Lift to Unlatch Push to Open 

(2) Lift Handle and Push out to Open 

When a release mechanism is not located within 
an occupant space of an adjacent seat, a label 
meeting the requirements of S5.5.2 that indicates 
the location of the nearest release mechanism 
shall be placed within the occupant space. 

Example: Emergency exit instructions located 
next to seat ahead. 

55.5.2 In buses other than school buses, except as 
provided in S5.5.2.1, each marking shall be leg- 
ible, when the only source of light is the normal 
night-time illumination of the bus interior, to 
occupants having corrected visual acuity of 20/40 
(Snellen ratio) seated in the adjacent seat, seated 
in the seat directly adjoining the adjacent seat, and 
standing in the aisle location that is closest to that 
adjacent seat. The marking shall be legible from 
each of these locations when the other two cor- 
responding locations are occupied. 

S5.5.2.1 If the exit has no adjacent seat, the mark- w 
ing must meet the legibility requirements of S5.5.2 
for occupants standing in the aisle location nearest 
to the emergency exit, except for a roof exit, 
which must meet the legibility requirements for 
occupants positioned with their backs against the 
floor opposite the roof exit. 

55.5.3 School Bus. Each school bus emergency 
exit provided in accordance with S5.2.3.1 shall 
have the designation "Emergency Door" or 
"Emergency Exit," as appropriate, in letters at 
least 2 inches high, of a color that contrasts with 
its background, located at the top of or directly 
above the emergency exit on both the inside and 
outside surfaces of the bus. Concise operating 
instructions describing the motions necessary to 
unlatch and open the emergency exit, in letters at 
least three-eighths of an inch high, of a color that 



(Rev. 11/2/92) 



PART 571; S 217-8 




Floor Beneath Emergency Exit 
View Parallel To Seat Back 



Floor Beneatti Emergency Exit 
View Pertendlculer To Seat Back 



Figure 1 .—Low-Force Access Region for Emergency Exits Having Adjacent Seats 




Floor Beneath Emeroency Exit 
View Parallel To Seat Back 

' Clearance area around seat back, arm rests, ar 



Emergency Exit 
View Perpendicular To Seat Back 



Figure 2.— High-Force Access Regions for Emergency Exits Having Adjacent Seats 



PART 571; S 217-9 



LOW- AND HIGH-FORCE ACCESS REGIONS FOR EMERGENCY EXITS 
WITHOUT ADJACENT SEATS 







Figure 3A.— Side Emergency Exit 




Figure 3B. — Roof Emergency Exit 



PART 571; S 217-10 




Inside Floor of Upright Bus 

* Typical clearance around obstructions 



Figure 3C.— Rear Emergency Exit Witli Rear Obstruction 




Access Region 
For High Forces 




J— ^ 



I— 52 Inches 



71 Inches 
52 Inches 



XI 



u, 



Figure 3D. — Rear Emergency Exit Without Rear Obstruction 



PART 571; S 217-11 



Retainer 
(Design Optional) 




.250 ±.025 Synthetic Underlayei 
250 ±25 pal Tensile Strength 
50 ±10% Elongation 

NAPA Qoat Skin, Wet Chamois, or 
.030±.003 Synthetic Skin 
1000 ±50 psi Tensile Strength 
100 ±5% Elongation 



Ail Dimensions In Inches 
Unless Otherwise Specified 



Figure 4 



PART 571; S 217-12 



Front 



Sides of Bus Body 



Side Emergency 
Exit Door *<xw 



/ 



^ s-^ .s ^i 



I 



30 cm 
Minimum 



Centeriine of Bus 



Figure 5A 



PART 571: S 217-13 




Figure 5B 




Figure 5C 



PART 571; S 217-14 



Table 1. Minimum Specific Intensity Per Unit Area (SIA) 

(Candelas per Footcandle Per Square Foot) 

Type 111 Retroreflective Material 

A — Glass Bead Retroreflective Element Material 



Observation Angle (°) 


Entrance Angle (°) 


White 


Red 


Yellow 


0.2 


-4 


250 


45 


170 


0.2 


+30 


150 


25 


100 


0.5 


-4 


95 


15 


62 


0.5 


+30 


65 


10 


45 


B— Prismatic Retroreflective Element Material 


Observation Angle (°) 


Entrance Angle (°) 


White 


Red 


Yellow 


0.2 


-4 


250 


45 


170 


0.2 


+30 


95 


13.3 


64 


0.5 


-4 


200 




136 


0.5 


+30 


65 


10 


45 



contrasts with its background, shall be located 
within 6 inches of the release mechanism on the 
inside surface of the bus. 
Example: 

(1) Lift to Unlatch 

Push to Open 

(2) Lift Handle 

Push Out to Open. 

S5.5.3 School Bus. 

(a) Each school hiis emergency exit provided in 
accordance with S5.2.3.1 shall have the designa- 
tion "Emergency Door" or "Emergency Exit," 
as appropriate, in letters at least 5 centimeters 
high, of a color that contrasts with its hack- 
ground. For emergency exit doors, the designa- 
tion shall be located at the top of, or directly 
above, the emergency exit door on both the inside 
and outside surfaces of the bus. The designation 
for roof exits shall be located on an inside sur- 
face of the exit, or within 30 centimeters of the 
roof e.xit opening. For emergency window exits, 
the designation shall be located at the top of, or 
directly above, or at the bottom of the emergency 
window exit on both the inside and outside sur- 
faces of the bus. 

(b) Concise operating instructions describing 
the motions necessary to unlatch and open the 
emergency e.xit shall be located within J5 centi- 
meters of the release mechanism on the inside 
surface of the bus. These instructions shall be in 



letters at least 1 centimeter high and of a color 
that contrasts with its background 
Example: 

(J) Lift to Unlatch, Push to Open 
(2) Turn Handle, Push Out to Open 
(c) Each opening for a required emergency exit 
shall be outlined around its outside perimeter 
with a minimum 3 centimeters wide retroreflective 
tape, either red, white, or yellow in color, that, 
when tested under the conditions specified in S6.1 
of 571.131, meets the criteria specified in Table 
1. (57 F.R. 49413— November 2, 1992. Effec- 
tive: May 2, 1994)] 

S6. Test conditions. 

56.1 The vehicle is on a flat, horizontal surface. 

56.2 The inside of the vehicle and the outside 
environment are kept at any temperature from 70° 
to 85° Fahrenheit for 4 hours immediately preced- 
ing the tests and during the tests. 

56.3 For the window retention test, windows are 
installed, closed, and latched (where latches are 
provided) in the condition intended for normal bus 
operation. 

56.4 For the emergency exit release and extension 
tests, windows are installed as in S6.3, seats, arm- 
rests, and interior objects near the windows are 
installed as for normal use, and seats are in the 
upright position. ^^ p ^ g^g^ 

May 10, 1972 



PART 571: S 217-15 



^ 



(: 



PREAMBLE TO AN AMENDMENT TO PART 572 
Anthropomorphic Test Dummies 
(Docket and RIN Numbers Not Issued) 



ACTION: Final rule; technical amendment. 

SUMMARY: This rule corrects the erroneous dates 
shown in the Code of Federal Regulations for the 
Anthropomorphic Test Dummy Parts List and the 
Parts List Index for the Hybrid III test dummy. 

EFFECTIVE DATE: October 14, 1992. 

SUPPLEMENTARY INFORMATION: 49 CFR Part 
572, Anthropomorphic Test Dummies, specifies 
the dimensions, physical attributes, and perform- 
ance characteristics of the Hybrid III test dummy 
in Subpart E. A general description of the Hybrid 
III test dummy is set forth m 572.31(a), which ref- 
erences six items that comprise the drawing and 
specifications package for the test dummy. The 
first of these six items is set forth in 572.31(a)(1) 
as follows: 

The Anthropomorphic Test Dummy Parts List, 
dated December 15, 1987, and containing 13 
pages, and a Parts List Index, dated December 
15, 1987, containing 8 pages. 
The Dummy Parts List and the Parts List Index 
were approved for incorporation by reference by 
the Director of the Federal Register. As a part of 
that approval, the Dummy Parts List and the Parts 
List Index are on file in the reference library of 
the office of the Federal Register and in the gen- 
eral reference section of the NHTSA Docket Sec- 
tion. However, the Dummy Parts List and the 
Parts List Index that are on file are both dated 
March 10, 1988. These March 10, 1988 lists are 



the correct version and the Parts List Index that 
the agency intended to incorporate into 49 CFR 
Part 572. Accordingly, this rule amends 572.31(a) 
so that it refers to the Dummy Parts List and 
Parts List Index of March 10, 1988. 

This correction imposes no duties or respon- 
sibilities on any party, nor does it alter any exist- 
ing obligations. Instead, it simply ensures that the 
public will have an accurate copy of Part 572 in 
Title 49 of the Code of Federal Regulations. 
Accordingly, NHTSA finds for good cause that 
notice and opportunity for comment on this 
correction are unnecessary, and this correction is 
effective upon publication in the Federal Register. 

In consideration of the foregoing, 49 CFR 
§ 572.31(a)(1) amended as follows: Section 
572.31 is amended by revising paragraph (a)(1) to 
read as follows: 572.31 General description. 

(a) 



(1) The Anthropomorphic Test Dummy Part 
List, dated March 10, 1988, and containing 13 
pages, and a Parts List Index, dated March 10, 
1988, containing 8 pages. 

***** 

Issued on October 7, 1992. 

Marion C. Blakey 
Administrator 

57 F.R. 47009 
October 14, 1992 



PART 572— PRE- 1 03 



PART 572— ANTHROPOMORPHIC TEST DUMMIES 



Subpart A— General 

§572.1 Scope. This part describes the 
anthropomorphic test dummies that are to be used 
for comphance testing of motor vehicles and 
motor vehicle equipment with motor vehicle 
safety standards. 

§572.2 Purpose. The design and performance 
headings: criteria specified in this part are 
intended to describe measuring tools with suffi- 
cient precision to give repetitive and correlative 
results under similar test conditions and to reflect 
adequately the protective performance of a vehicle 
or item, of motor vehicle equipment, with respect 
to human occupants. 

§572.3 Application. This part does not in itself 
impose duties or liabilities on any person. It is a 
description of tools that measure the performance 
of occupant protection systems required by the 
safety standards that incorporate it. It is designed 
to be referenced by, and become a part of, the test 
procedures specified in motor vehicle safety stand- 
ards such as Standard No. 208, Occupant Crash 
Protection. 

§572.4 Terminology. 

(a) The tenn "dummy," when used in this 
Subpart A, refers to any test device described by 
this part. The term "dummy," when used in any 
other subpart of this part, refers to the particular 
dummy described in that part. 

(b) Terms describing parts of the dummy, such 
as "head," are the same as names for cor- 
responding parts of the human body. 

(c) The term "unimodal," when used in 
[Subpart C and I], refers to an acceleration-time 
curve which has only one prominent peak. (56 

F.R. 57830 November 14, 1991. Effective: May 

12, 1992) 

Subpart B— 50th Percentile Male 

§572.5 General description. 

(a) The dummy consists of the component 
assemblies specified in Figure 1, which are 



described in their entirety by means of approxi- 
mately 250 drawings and specifications that are 
grouped by component assemblies under the fol- 
lowing nine headings: 



SA 150 M070 
SA 150M071 
SA 150 M050 
SA 150 M060 

SA 150 M080 
SA 150M081 
SA 150 MOlO 
SA 150 M020 
SA 150 M030 



Right arm assembly 
Left arm assembly 
Lumbar spine assembly 
Pelvis and abdomen 
assembly 

Right leg assembly 
Left leg assembly 
Head assembly 
Neck assembly 
Shoulder-thorax assembly 



(b) The drawings and specifications referred to 
in fros regulation that are not set forth in full are 
hereby incorporated in this part by reference. 
These materials are thereby made part of this 
regulation. The Director of the Federal Register 
has approved the materials incorporated by ref- 
erence. For materials subject to change, only the 
specific version approved by the Director of the 
Federal Register and specified in the regulation 
are incorporated. A notice of any change will be 
published in the Federal Register. 

(c) The materials incorporated by reference are 
available for exatnination in Docket 73-08, 
Docket Section, National Highway Traffic Safety 
Administration, Room 5109, 400 Seventh Street 
S.W., Washington, D.C. 20590. Copies may be 
obtained from Rowley-Scher Reprographics, Inc., 
1216 K Street N.W., Washington, D.C. 20005 
(202) 628-6667. The drawings and specifications 
are also on file in the reference library of the 
Office of the Federal Register, National Archives 
and Records Administration, Washington, D.C. 

(d) Adjacent segments are joined in a manner 
such that throughout the range of motion and also 
under crash-impact conditions there is no contact 
between metallic elements except for contacts that 
exist under static conditions. 

(e) The structural properties of the dummy are 
such that the dummy conforms to this part in 



(Rev. 11/14/91) 



every respect both before and after being used in 
vehicle tests specified in Standard No. 208 
(§571.208). 

(f) A specimen of the dummy is available for 
surface measurements, and access can be arranged 
through: Office of Vehicle Safety Standards, 
National Highway Traffic Safety Administration, 
400 Seventh Street, S.W., Washington, D.C. 
20590. 

§572.6 Head. 

(a) The head consists of the assembly shown as 
number SA 150 MO 10 in Figure 1 and conforms 
to each of the drawings subtended by number SA 
150 MOIO. 

(b) When the head is dropped from a height of 
10 inches in accordance with paragraph (c) of this 
section, the peak resultant accelerations at the 
location of the accelerometers mounted in the 
head form in accordance with §572.1 1(b) shall be 
not less than 210g. and not more than 260g. The 
acceleration/time curve for the test shall be 
unimodal and shall lie at or above the lOOg level 
for an interval not less than 0.9 milliseconds and 
not more than 1.5 milliseconds. The lateral accel- 
eration vector shall not exceed lOg. 

(c) Test procedure: 

(1) Suspend the head as shown in Figure 2, 
so that the lowest point on the forehead is 0.5 
inches below the lowest point on the dummy's 
nose when the midsagittal plane is vertical. 

(2) Drop the head from the specified height 
by a means that ensures instant release onto a 
rigidly supported flat horizontal steel plate, 2 
inches thick and 2 feet square, which has a 
clean, dry surface and any microfinish of not 
less than 8 microinches (rms) and not more 
than 80 microinches (rms). 

(3) Allow a time period of at least 2 hours 
between successive tests on the same head. 

§572.7 Neck. 

(a) The neck consists of the assembly shown as 
number SA 150 M020 in Figure 1 and conforms 
to each of the drawings subtended by number SA 
150 M020. 

(b) When the neck is tested with the head in 
accordance with paragraph (c) of this section, the 
head shall rotate in reference to the pendulum's 
longitudinal centerline a total of 68° ± 5° about 
its center of gravity, rotating to the extent speci- 



fied in the following table at each indicated point 
in time, measured from impact, with a chordal 
displacement measured at its center of gravity that 
is within the limits specified. The chordal 
displacement at time T is defined as the straight 
line distance between (1) the position relative to 
the pendulum arm of the head center of gravity 
at time zero, and (2) the position relative to the 
pendulum arm of the head center of gravity at 
time T as illustrated by Figure 3. The peak result- 
ant acceleration recorded at the location of the 
accelerometers mounted in the head form in 
accordance with §572. 11(b) shall not exceed 26g. 
The pendulum shall not reverse direction until the 
head's center of gravity returns to the original 
zero time position relative to the pendulum arm. 



Rotation (degrees) 



Time (ms) ± 
(2 + ,08T) 



Chordal 
Displacement 
(inches ±0.5) 









0.0 


30 


30 


2.6 


60 


46 


4.8 


Maximum 


60 


5.5 


60 


75 


4.8 


30 


95 


2.6 





112 


0.0 



(c) Test procedure: 

(1) Mount the head and neck on a rigid pen- 
dulum as specified in Figure 4, so that the 
head's midsagittal plane is vertical and 
coincides with the plane of motion of the pen- 
dulum's longitudinal centerline. Mount the neck 
directly to the pendulum as shown in Figure 4. 

(2) Release the pendulum and allow it to fall 
freely from a height such that the velocity at 
impact is 23.5 ± 2.0 feet per second (fps), 
measured at the center of the accelerometer 
specified in Figure 4. 

(3) Decelerate the pendulum to a stop with 
an acceleration-time pulse described as follows: 

(i) Establish 5g and 20g levels on the a — t 
curve. 

(ii) Establish t| at the point where the ris- 
ing a — t curve first crosses the 5g level, ij 
at the point where the rising a — t curve first 
crosses the 20g level, ts at the point where 
the decaying a — t curve last crosses the 20g 
level, and t4 at the point where the decaying 
a — t curve first crosses the 5g level. 

(iii) t2-ti shall be not more than 3 milli- 
seconds. 

(iv) t3-t2 shall be not less than 25 milli- 
seconds and not more than 30 milliseconds. 



PART 572-2 



(v) t4 — 13 shall be not more than 10 milli- 
seconds. 

(vi) The average deceleration between t2 
and t3 shall be not less than 20g and not 
more than 24g. 

(4) Allow the neck to flex without impact of 
the head or neck with any object other than the 
pendulum arm. 

§572.8 Thorax. 

(a) The thorax consists of the assembly shown 
as number SA 150 M030 in Figure 1, and con- 
forms to each of the drawings subtended by num- 
ber SA 150 M030. 

(b) The thorax contains enough unobstructed 
interior space behind the rib cage to permit the 
midpoint of the sternum to be depressed 2 inches 
without contact between the rib cage and other 
parts of the dummy or its instrumentation, except 
for instruments specified in subparagraph (d)(7) 
of this section. 

(c) When impacted by a test probe conforming 
to §572.1 1(a) at 14 fps and at 22 fps in accord- 
ance with paragraph (d) of this section, the thorax 
shall resist with forces measured by the test probe 
of not more than 1450 pounds and 2250 pounds, 
respectively, and shall deflect by amounts not 
greater than 1.1 inches and 1.7 inches, respec- 
tively. The internal hysteresis in each impact shall 
not be less than 50 percent and not more than 70 
percent. 

(d) Test Procedure: 

(1) With the dummy seated without back 
support on a surface as specified in §572.11(1) 
and in the orientation specified in §572.11(1), 
adjust the dummy arms and legs until they are 
extended horizontally forward parallel to the 
midsagittal plane. 

(2) Place the longitudinal center line of the 
test probe so that it is 17.7 ± 0.1 inches above 
the seating surface at impact. 

(3) Align the test probe specified in §572.11 
(a) so that at impact its longitudinal centerline 
coincides within 2 degrees of a horizontal line 
in the dummy's midsagittal plane. 

(4) Adjust the dummy so that the surface 
area on the thorax immediately adjacent to the 
projected longitudinal center line of the test 
probe is vertical. Limb support, as needed to 
achieve and maintain this orientation, may be 
provided by placement of a steel rod of any 



diameter not less than one-quarter of an inch 
and not more than three-eighths of an inch, 
with hemispherical ends, vertically under the 
limb at its projected geometric center. 

(5) Impact the thorax with the test probe so 
that its longitudinal centerline falls within 2 
degrees of a horizontal line in the dummy's 
midsagittal plane at the moment of impact. 

(6) Guide the probe during impact so that it 
moves with no significant lateral, vertical, or 
rotational movement. 

(7) Measure the horizontal deflection of the 
sternum relative to the thoracic spine along the 
line established by the longitudinal centerline 
of the probe at the moment of impact, using a 
potentiometer mounted inside the sternum. 

(8) Measure hysteresis by determining the 
ratio of the area between the loading and 
unloading portions of the force deflection curve 
to the area under the loading portion of the 
curve. 

§572.9 Lumbar spine, abdomen, and pelvis. 

(a) The lumbar spine, abdomen, and pelvis con- 
sist of the assemblies designated as numbers SA 
150 M050 and SA 150 M060 in Figure 1 and 
conform to the drawings subtended by these num- 
bers. 

(b) When subjected to continuously applied 
force in accordance with paragraph (c) of this sec- 
tion, the lumbar spine assembly shall flex by an 
amount that permits the rigid thoracic spine to 
rotate from its initial position in accordance with 
Figure 1 1 by the number of degrees shown below 
at each specified force level, and straighten upon 
removal of the force to within 12 degrees of its 
initial position in accordance with Figure 1 1 . 



Flexion (degrees) 



20 

30 

40 



Force 
(±6 pounds) 


28 
40 
52 



(c) Test procedure: 

(1) Assemble the thorax, lumbar spine, pel- 
vic, and upper leg assemblies (above the femur 
force transducers), ensuring that all component 
surfaces are clean, dry, and untreated unless 
otherwise specified, and attach them to the 
horizontal fixture shown in Figure 5 at the two 



PART 572-3 



link rod pins and with the mounting brackets 
for the lumbar test fixtures illustrated in Figure 
6 to 9. 

(2) Attach the rear mounting of the pelvis to 
the pelvic instrument cavity rear face at the 
four V/' cap screw holes and attach the front 
mounting at the femur axial rotation joint. 
Tighten the mountings so that the pelvic-lum- 
bar adapter is horizontal and adjust the femur 
friction plungers at each hip socket joint to 240 
inch-pounds torque. 

(3) Flex the thorax forward 50° and the rear- 
ward as necessary to return it to its initial posi- 
tion in accordance with Figure 1 1 unsupported 
by external means. 

(4) Apply a forward force perpendicular to 
the thorax instrument cavity rear face in the 
midsagittal plane 15 inches above the top sur- 
face of the pelvic-lumbar adapter. Apply the 
force at any torso deflection rate between .5 
and 1 .5 degrees per second up to 40° of flexion 
but no further, continue to apply for 10 seconds 
that force necessary to maintain 40° of flexion, 
and record the force with an instrument 
mounted to the thorax as shown in Figure 5. 
Release all force as rapidly as possible and 
measure the return angle 3 minutes after the 
release. 

(d) When the abdomen is subjected to continu- 
ously applied force in accordance with paragraph 
(e) of this section, the abdominal forcedeflection 
curve shall be within the two curves plotted in 
Figure 10. 

(e) Test procedure: 

(1) Place the assembled thorax, lumbar spine, 
and pelvic assemblies in a supine position on 
a fiat rigid, smooth, dry, clean horizontal sur- 
face, ensuring that all component surfaces are 
clean, dry, and untreated unless otherwise 
specified. 

(2) Place a rigid cylinder 6 inches in diame- 
ter and 18 inches long transversely across the 
abdomen, so that the cylinder is symmetrical 
about the midsagittal plane, with its longitu- 
dinal centerline horizontal and perpendicular to 
the midsagittal plane at a point 9.2 inches 
above the bottom line of the buttocks, meas- 
ured with the dummy positioned in accordance 
with Figure 1 1 . 



(3) Establish the zero deflection point as the 
point at which a force of 10 pounds has been 
reached. ^ 

(4) Apply a vertical downward force through ^ 
the cylinder at any rate between 0.25 and 0.35 
inches per second. 

(5) Guide the cylinder so that it moves with- 
out significant lateral or rotational movement. 

§572.10 Limbs. 

(a) The limbs consist of the assemblies shown 
as numbers SA 150 M070, SA 150 M071, SA 
150 M080, and SA 150 M081 in Figure 1 and 
conform to the drawings subtended by these num- 
bers. 

(b) When each knee is impacted at 6.9 ft/ sec. 
in accordance with paragraph (c) of this section, 
the maximum force on the femur shall be not 
more than 2500 pounds and not less than 1850 
pounds, with a duration above 1000 pounds of not 
less than 1.7 milliseconds. 

(c) Test procedure: 

(1) Seat the dummy without back support on 
a surface as specified in §572.11(1) that is 17.3 

± 0.2 inches above a horizontal surface, ori- ^ 
ented as specified in §572.11(1), and with the ^ 
hip joint adjustment at any setting between Ig 
and 2g. Place the dummy legs in planes parallel 
to its midsagittal plane (knee pivot centerline 
perpendicular to the midsagittal plane) and with 
the feet flat on the horizontal surface. Adjust 
the feet and lower legs until the lines between 
the midpoints of the knee pivots and the ankle 
pivots are at any angle not less than 2 degrees 
and not more than 4 degrees rear of the verti- 
cal, measured at the centerline of the knee piv- 
ots. 

(2) Reposition the dummy if necessary so 
that the rearmost point of the lower legs at the 
level one inch below the seating surface 
remains at any distance not less than 5 inches 
and not more than 6 inches forward of the for- 
ward edge of the seat. 

(3) Align the test probe specified in 
§S72.11(a) so that at impact its longitudinal 
centerline coincides within 20 with the longitu- 
dinal centerline of the femur. 

(4) Impact the knee with the test probe mov- 
ing horizontally and parallel to the midsagittal \^ 
plane at the specified velocity. 



PART 572^ 



(5) Guide the probe during impact so that it 
moves with no significant lateral, vertical, or 
rotational movement. 

§572.11 Test conditions and instrumentation. 

(a) The test probe used for thoracic and knee 
impact tests is a cylinder 6 inches in diameter that 
weighs 51.5 pounds including instrumentation. Its 
impacting end has a flat right face that is rigid 
and that has an edge radius of 0.5 inches. 

(b) Accelerometers are mounted in the head on 
the horizontal transverse bulkhead shown in the 
drawings subreferenced under assembly No. SA 
150 MO 10 in Figure 1, so that their sensitive axes 
intersect at a point in the midsagittal plane 0.5 
inches above the horizontal bulkhead and 1.9 
inches ventral of the vertical mating surface of 
the skull with the skull cover. One accelerometer 
is aligned with its sensitive axis perpendicular to 
the horizonal bulkhead in the midsagittal plane 
and with its seismic mass center at any distance 
up to 0.3 inches superior to the axial intersection 
point. Another accelerometer is aligned with its 
sensitive axis parallel to the horizontal bulkhead 
and perpendicular to the midsagittal plane, and 
with its seismic mass center at any distance up to 
1.3 inches to the left of the axial intersection 
point (left side of dummy is the same as that of 
man). A third accelerometer is aligned with its 
sensitive axis parallel to the horizontal bulkhead 
in the midsagittal plane, and with its seismic mass 
center at any distance up to 1.3 inches dorsal to 
the axial intersection point. 

(c) Accelerometers are mounted in the thorax 
by means of a bracket attached to the rear vertical 
surface (hereafter "attachment surface") of the 
thoracic spine so that their sensitive axes intersect 
at a point in the midsagittal plane 0.8 inches 
below the upper surface of the plate to which the 
neck mounting bracket is attached and 3.2 inches 
perpendicularly forward of the surface to which 
the accelerometer bracket is attached. One accel- 
erometer has its sensitive axis oriented parallel to 
the attachment surface in the midsagittal plane, 
with its seismic mass center at any distance up to 
1.3 inches inferior to the intersection of the sen- 
sitive axes specified above. Another accelerometer 
has its sensitive axis oriented parallel to the 
attachment surface and perpendicular to the 
midsagittal plane, with its seismic mass center at 
any distance up to 0.2 inches to the right of the 



intersection of the sensitive axes specified above. 
A third accelerometer has its sensitive axis ori- 
ented perpendicular to the attachment surface in 
the midsagittal plane, with its seismic mass center 
at any distance up to 1.3 inches dorsal to the 
intersection of the sensitive axes specified above. 
Accelerometers are oriented with the dummy in 
the position specified in §572.11(1). 

(d) A force-sensing device is mounted axially 
in each femur shaft so that the transverse center- 
line of the sensing element is 4.25 inches from 
the knee's center of rotation. 

(e) The outputs of acceleration and 
forcesensing devices installed in the dummy and 
in the test apparatus specified by this Part are 
recorded in individual data channels that conform 
to the requirements of SAE Recommended Prac- 
tice J211a, December 1971, with channel classes 
as follows: 

(1) Head acceleration— Class 1000. 

(2) Pendulum acceleration — Class 60. 

(3) Thorax acceleration — Class 180. 

(4) Thorax compression — Class 180. 

(5) Femur force— Class 600. 

(f) The mountings for sensing devices have no 
resonance frequency within a range of 3 times the 
frequency range of the applicable channel class. 

(g) Limb joints are set at Ig, barely restraining 
the weight of the limb when it is extended hori- 
zontally. The force required to move a limb seg- 
ment does not exceed 2g throughout the range of 
limb motion. 

(h) Performance tests are conducted at any 
temperature from 66° F to 78° F and at any rel- 
ative humidity from 10 percent to 70 percent after 
exposure of the dummy to these conditions for a 
period of not less than 4 hours. 

(i) For the performances tests specified in 
§§572.8, 572.9, and 572.10, the dummy is posi- 
tioned in accordance with Figure 1 1 as follows: 
(1) The dummy is placed on a flat, rigid, 
smooth, clean, dry, horizontal, steel test surface 
whose length and width dimensions are not less 
than 16 inches, so that the dummy's midsagittal 
plane is vertical and centered on the test sur- 
face and the rearmost points on its lower legs 
at the level of the test surface are at any dis- 
tance not less than 5 inches and not more than 
6 inches forward of the forward edge of the test 
surface. 



(2) The pelvis is adjusted so that the upper 
surface of the lumbar-pelvic adapter is hori- 
zontal. 

(3) The shoulder yokes are adjusted so that 
they are at the midpoint of their anterior pos- 
terior travel with their upper surfaces hori- 
zontal. 

(4) The dummy is adjusted so that the rear 
surfaces of the shoulders and buttocks are tan- 
gent to a transverse vertical plane. 

(5) The upper legs are positioned symmetri- 
cally about the midsagittal plane so that the 
distance between the knee pivot bolt heads is 
11.6 inches. 

(6) The lower legs are positioned in planes 
parallel to the midsagittal plane so that the 
lines between the midpoint of the knee pivots 
and the ankle pivots are vertical. 

(j) The dummy's dimensions, as specified in 
drawing number SA 150 M002, are determined as 
follows: 

(1) With the dummy seated as specified in 
paragraph (i), the head is adjusted and secured 
so that its occiput is 1.7 inches forward of the 
transverse vertical plane with the vertical mat- 
ing surface of the skull with its cover parallel 
to the transverse vertical plane. 

(2) The thorax is adjusted and secured so 
that the rear surface of the chest accelerometer 
mounting cavity is inclined 30 forward of verti- 
cal. 

(3) Chest and waist circumference and chest 
depth measurements are taken with the dummy 
positioned in accordance with paragraph (i) (1) 
and (2) of this section. 



(4) The chest skin and abdominal sac are 
removed and all following measurements are 
made without them. 

(5) Seated height is measured from the seat- 
ing surface to the uppermost point on the head- 
skin surface. 

(6) Shoulder pivot height is measured from 
the seating surface to the center of the arm ele- 
vation pivot. 

(7) H-point locations are measured from the 
seating surface to the center of the holes in the 
pelvis flesh covering in line with the hip 
motion ball. 

(8) Knee pivot distance from the backline is 
measured to the center of the knee pivot bolt 
head. 

(9) Knee pivot distance from floor is meas- 
ured from the center of the knee pivot bolt 
head to the bottom of the heel when the foot 
is horizontal and pointing forward. 

(10) Shoulder width measurement is taken at 
arm elevation pivot center height with the 
centerlines between the elbow pivots and the 
shoulder pivots vertical. 

(11) Hip width measurement is taken at 
widest point of pelvic section. 

(k) Performance tests of the same component, 
segment, assembly, or fully assembled dummy are 
separated in time by a period of not less than 30 
minutes unless otherwise noted. 

(1) Surfaces of dummy components are not 

painted except as specified in this part or in 

drawings subtended by this part. 



PART 572-6 



Arm Assembly 
SA 150 M070 Right 
SA 150 M071 Left 




Shoulder-Ttiorax 
Assembly 
SA 150 M030 



Leg Assembly 
SA 150 M080 Right 
SA 150 M081 Left 



Figure 2.— Head Positioning For Drop Tests 



Connecting Ring 




Steel Blocl^ 
2"x24"x24" 



HEAD POSITIONING FOR DROP TESTS 



Figure 2. 



Pendulum 
Pivot Point 




Head Rotation 



Chordal 
Displacement 



Figure 3.— Neck Component Test 



PART 572- Subpart B-ART PAGE 1 



Inertial Properties of Pendulum 
Without Test Specimen. 
Weigtit 65.2 lbs. 

Moment of Inertia 24.5 lb. ft. Sec 
About Pivot Axis 



CG of Pendulu 
Apparatus Without 
Test Specimen 



Accelerometer 



V,e" Structural 
Steel Tube 




Alummum Honeycomb 
(Hexcell 1.8 Ibs./cu. ft.) 
Ref. 



• 3" X 6" X ^/e" Plate (Sharp Edges) 
% " '^ CG of Test Specimen 



PART 572-Subpart B-ART PAGE 2 



Line of Force Application 




Figure 9. 

Attachment 10-32 Screws 

(Four Places) 



Figure 



Link Rod (Items F/04 and G/04 
Drawing Number SA 150 M002 Sheet 1.) 
Attachment to Bedplate 
With '/,-24 Bolts 





^l,.^ 


t 


1 1 1 1 


2- ¥4 




)-■ 


1 Ml 

V Vl 1 


2-V. 




1 r 


_k_,__i.^ 




i '■- ' 

— *1 |-^'/aV\ 



'/, Wide Slot 

(Two Places) t* ^■'^'- 



W"^ 



i 2-V. 



Vl Sq. Steel Stock 7- '/a Long 
Welded to Angle 




6x6 Structural Steel Angle 



PART 572-Subpart B-ART PAGE 

















"/ 


'r-'i "-< 




- t 

I-'/,. ± 

i 


1 1 r'^' 


1 1 1 


















V V ' 


1 1 1 

-U- 
















\' 






3-'V, 




-^i-y. -— 






V '/j; Drill Thru 
4 Places 










H 


/T/I 


2.0 

1 








■^ V„-24 Tap Thru (2 Holes) 




Tolerance ± '/,/' 
Material: Steel 
Welded Construction 



»;„ Drill Ttin 
'/8-24 Tap Thru Top Plate / 2 Places 
and Top of Tubing 




24 1 



^15.V,-J 




'/„ Drill Hole <t 



PART 572-Subpart B-ART PAGE 4 



M1_L 

.25 



Ttr|".25 



Construction: Aluminum or Steel Weldment 
Tolerance: ± .03 Two Places 

± .005 Three Places 



r 



3.000 
■ 3.50 • 



.-.^ 



I 1 -^^ °'^ 



Clear Drill For 
10-32 Screw 
4 Places 



.25R (4 Places) 





90 










1 

i 






80 


- 






! 

1 




..^— 73 




70 


~ 






J/ 






i 


60 


— 




^ 


^ 

y 








50 
40 
30 
20 

10 


- 


^^ 


1 1 


1 
1 


1 








0.25 


0.50 0.75 


1.00 


1.30 








DISPLACEMENT (Inches) 









PART 572-Subpart B-ART PAGE 5 



Spacer (Ref.) 



3° (Ref.) 



Vertical Mating Surface of Skull 
Parallel to ttie Vertical Backline 




Tangent 



Arm 

Elevation 

Pivot 




Shoulder Yoke Upper Surface 
Horizontal and Centered at 
Mid-Travel in Anterior-Pos- 
Terlor Director. 



Lumbar— Pelvic Adaptor 
Upper Surface Horizontal 




PART 572-Subpart B-ART PAGE 6 



> 



Space for figures 12 thru 14 
reserved for future use. 



> 



> 

PART 572-Subpart B-ART PAGE 7 



# 



Subpart C— Three Year Old Child 

§572.15 General description. 

(a) The dummy consists of the component 
assembhes specified in drawing SA 103C 001, 
which are described in their entirety by means of 
approximately 122 drawings and specifications 
and an Operation and Maintenance Manual, dated 
May 28, 1976. The drawings and specifications 
are grouped by component assemblies under the 
following thirteen headings: 

SA 103C 010 Head Assembly 

SA 103C 020 Neck Assembly 

SA 103C 030 Torso Assembly 

SA 103C 041 Upper Ann Assembly Left 

SA 103C 042 Upper Ann Assembly Right 

SA 103C 051 Foreami Hand Assembly Left 

SA 103C 052 Foreami Hand Assembly 

Right 

SA 103C 061 Upper Leg Assembly Left 

SA 103C 062 Upper Leg Assembly Right 

SA 103C 071 Lower Leg Assembly Left 

SA 103C 072 Lower Leg Assembly Right 

SA 103C 081 Foot Assembly Left 

SA 103C 082 Foot Assembly Right 

(b) The drawings, specifications, and operation 
and maintenance manual referred to in this regu- 
lation that are not set forth in full are hearby 
incorporated in this Part by reference. These 
materials are thereby made part of this regulation. 
The Director of the Federal Register has approved 
the materials incorporated by reference. For mate- 
rials subject to change, only the specific version 
approved by the Director of the Federal Register 
and specified in the regulation are incorporated. A 
notice of any change will be published in the 
Federal Register. As a convenience 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. 

(c) The materials incorporated by reference are 
available for examination in Docket 78-09. Room 
5109, Docket Section, National Highway Traffic 
Safety Administration, 400 Seventh Street S.W., 
Washington, D.C. 20590. Copies may be obtained 
from Rowley-Scher Reprographics, Inc., 1216 K 
Street, N.W., Washington, D.C. 20005, ((202) 
628-6667). The materials are also on file in the 
reference library of the Federal Register, National 
Archives and Records Administration, Washing- 
ton, D.C. 



(d) Adjacent segments are joined in a manner 
such that throughout the range of motion and also 
under simulated crash-impact conditions, there is 
no contact between metallic elements except for 
contacts that exist under static conditions. 

(e) The structural properties of the dummy are 
such that the dummy conforms to this part in 
every respect both before and after being used in 
vehicle tests specified by Standard No. 213 of this 
chapter (§571.213). 

(f) The patterns of all cast and molded parts for 
reproduction of the molds needed in manufactur- 
ing of the dummies can be obtained on a loan 
basis by manufacturers of the test dummies, or 
others if need is shown, from the Office of 
Vehicle Safety Standards, NHTSA, 400 Seventh 
Street S.W., Washington, D.C. 20590. 

§572.16 Head. 

(a) [The head consists of the assembly des- 
ignated as SA 103C 010 on drawing no. SA 103C 
001, and conforms to either — 

(1) each item specified on drawing SA 103C 
002(B), sheet 8; or 

(2) each item specified on drawing SA 103C 
002, sheet 8. 

(b) When the head is impacted by a test probe 
specified in §572.2 1(a)(1) at 7 fps., then the peak 
resultant acceleration measured at the location of 
the accelerometer mounted in the headform in 
according to §572.2 1(b) is not less than 95g, and 
not more than 118g. 

(1) The recorded acceleration-time curve for 
this test is unimodal at or above the 50g level, 
and lies at or above that level for intervals: 

(i) in the case of the head assembly speci- 
fied in paragraph (a)(1) of this section, not 
less than 1.3 milliseconds and not more than 
2.0 milliseconds; 

(ii) in the case of the head assembly speci- 
fied in paragraph (a)(2) of this section, not 
less than 2.0 milliseconds and not more than 
3.0 milliseconds. 

(2) The lateral acceleration vector shall not 
exceed 7g. (55 F.R. 30465— July 26, 1990. Effec- 
tive: August 27, 1990)] 

(c) Test Procedure: 

(1) Seat the dummy on a seating surface 
having a back support as specified in 
§ 572.21(h) and orient the dummy in accord- 
ance with § 572.21(h) and adjust the joints of 



(Rev. 7/26/90) 



the limbs at any setting between Ig and 2g, 
which just supports the limbs" weight when the 
limbs are extended horizontally forward. 

(2) Adjust the test probe so that its longitu- 
dinal centerline is at the forehead at the point 
of orthogonal intersection of the head 
midsagittal plane and the transverse plane 
which is perpendicular to the "Z" axis of the 
head (longitudinal centerline of the skull 
anchor) and is located 0.6 ± .1 inches above the 
centers of the head center of gravity reference 
pins and coincides within 2 degrees with the 
line made by the intersection of horizontal and 
midsagittal planes passing through this point. 

(3) Adjust the dummy so that the surface 
area on the forehead immediately adjacent to 
the projected longitudinal centerline of the test 
probe is vertical. 

(4) Impact the head with the test probe so 
that at the moment of impact the probe's 
longitudinal centerline falls within 2 degrees of 
a horizontal line in the dummy's midsagittal 
plane. 

(5) Guide the probe during impact so that it 
moves with no significant lateral, vertical, or 
rotational movement. 

(6) Allow a time period of at least 20 min- 
utes between successive tests of the head. 

§572.17 Neck. 

[(a)(1) The neck for use with the head assem- 
bly described in § 572.16(a)(1) consists of the 
assembly designated as SA 103C 020 on drawing 
No. SA 103C 001, and conforms to each item 
specified on drawing No. SA 103C 002(B), sheet 
9. 

(2) The neck for use with the head assembly 
described in § 572.16(a)(2) consists of the 
assembly designated as SA 103C 020 on draw- 
ing No. SA 103C 001, and confomis to each 
item specified on drawing No. SA 103C 002, 
sheet 9. (55 F.R. 30465— .luly 26, 1990. Effec- 
tive: August 27, 1990)] 



(degrees) 



Time (ms) 
±(2 + .08T) 



Chordal 
Displacemei 
(inches ±0.f 





30 

60 

Maximum 

60 

30 



(Rev. 7/26/90) 









21 


2.2 


36 


4.3 


62 


5.8 


91 


4.3 


108 


2.2 


123 







PART 572- 



(b) When the head-neck assembly is tested in 
accordance with paragraph (c) of this section, the 
head shall rotate in reference to the pendulum's 
longitudinal centerline a total of 84 degrees ± 8 
degrees about its center of gravity, rotating to the 
extent specified in the following table at each 
indicated point in time, measured from impact, 
with the chordal displacement measured at its 
center of gravity. The chordal displacement at 
time T is defined as the straight line distance 
between (1) the position relative to the pendulum 
arm of the head center of gravity at time zero, 
and (2) the position relative to the pendulum arm 
of the head center of gravity at time T as illus- 
trated by Figure 3. The peak resultant acceleration 
recorded at the location of the accelerometers 
mounted in the headform in accordance with 
§ 572.21(b) shall not exceed 30g. The pendulum 
shall not reverse direction until the head's center 
of gravity returns to the original zero time posi- 
tion relative to the pendulum arm. 

(c) Test Procedure: 

(1) Mount the head and neck on a rigid pen- 
dulum as specified in Figure 4, so that the 
head's midsagittal plane is vertical and 
coincides with the plane of motion of the pen- 
dulum's longitudinal centerline. Mount the neck 
directly to the pendulum as shown in Figure 
15. 

(2) Release the pendulum and allow it to fall 
freely from a height such that the velocity at 
impact is 17.00 ± 1.0 feet per second (fps), 
measured at the center of the accelerometer 
specified in Figure 4. 

(3) Decelerate the pendulum to a stop with 
an acceleration-time pulse described as follows: 

(i) Establish 5g and 20g levels on the a-t 
curve. 

(ii) Establish t| at the point where the a-t 
curve first crosses the 5g level, t2 at the 
point where the rising a-t curve first 
crosses the 20g level, U at the point where 
the decaying a — t curve last crosses the 20g 
level, and U at the point where the decaying 
a-t curve first crosses the 5g level. 

(iii) t2 — ti, shall be not more than 4 milli- 
seconds. 

(iv) t3-t2, shall be not less than 18 and 
not more than 21 milliseconds. 

(v) t4-t3, shall be not more than 5 milli- 
seconds. 



(vi) The average deceleration between t^ 
and t3 shall be not less than 20g and not 
more than 34g. 

(4) Allow the neck to flex without contact of 
the head or neck with any object other than the 
pendulum arm. 

(5) Allow a time period of at least 1 hour 
between successive tests of the head and neck. 

§572.18 Thorax. 

(a) The thorax consists of the part of the torso 
shown in assembly drawing SA 103C 001 by 
number SA 103C 030 and conforms to each of 
the applicable drawings listed under this number 
on drawings SA 103C 002, sheets 10 and 11. 

(b) When impacted by a test probe conforming 
to § 572.21(a) at 13 fps. in accordance with para- 
graph (c) of this section, the peak resultant accel- 
erations at the location of the accelerometers 
mounted in the chest cavity in accordance with 
§572.2 1(c) shall be not less than 50g and not 
more than 70g. The acceleration-time curve for 
the test shall be unimodal at or above the 30g 
level and shall lie at or above the 30g level for 
an interval not less than 2.5 milliseconds and not 
more than 4.0 milliseconds. The lateral accelera- 
tion shall not exceed 5g. 

(c) Test Procedure: 

(1) With the dummy seated without back 
support on a surface as specified in § 572.21(h) 
and oriented as specified in § 572.21(h), adjust 
the dummy arms and legs until they are 
extended horizontally forward parallel to the 
midsagittal plane, the joints of the limbs are 
adjusted at any setting between Ig and 2g, 
which just supports the limbs' weight when the 
limbs are extended horizontally forward. 

(2) Establish the impact point at the chest 
midsagittal plane so that it is 1.5 inches below 
the longitudinal centerline of the bolt that 
attaches the top of the ribcage sternum to the 
thoracic spine box. 

(3) Adjust the dummy so that the tangent 
plane at the surface on the thorax immediately 
adjacent to the designated impact point is verti- 
cal and parallel to the face of the test probe. 

(4) Place the longitudinal centerline of the 
test probe to coincide with the designated 
impact point and align the test probe so that at 
impact its longitudinal centerline coincides 
within 2 degrees with the line formed by inter- 



section of the horizontal and midsagittal planes 
passing through the designated impact point. 

(5) Impact the thorax with the test probe so 
that at the moment of impact the probe's 
longitudinal centerline falls within 2 degrees of 
a horizontal line in the dummy midsagittal 
plane. 

(6) Guide the probe during impact so that it 
moves with no significant lateral, vertical or 
rotational movement. 

(7) Allow a time period of at least 20 min- 
utes between successive tests of the chest. 

§572.19 Lumbar spine, abdomen and pelvis. 

(a) The lumbar spine, abdomen, and pelvis con- 
sist of the part of the torso assembly shown by 
number SA 103C 030 on drawing SA 103C 001 
and conform to each of the applicable drawings 
listed under this number on drawing SA 103C 
002, sheets 10 and 11. 

(b) When subjected to continuously applied 
force in accordance with paragraph (c) of this sec- 
tion, the lumbar spine assembly shall flex by an 
amount that permits the rigid thoracic spine to 
rotate from its initial position in accordance with 
Figure 18 of this subpart by 40 degrees at a force 
level of not less than 34 pounds and not more 
than 47 pounds, and straighten upon removal of 
the force to within 5 degrees of its initial position. 

(c) Test Procedure: (1) The dummy with lower 
legs removed is positioned in an upright seated 
position on a seat as indicated in Figure 18, 
ensuring that all dummy component surfaces are 
clean, dry and untreated unless otherwise speci- 
fied. 

(2) Attach the pelvis to the seating surface 
by a bolt C/328, modified as shown in Figure 
18, and the upper legs at the knee axial rotation 
joints by the attachments shown in Figure 18. 
Tighten the mountings so that the pelvis-lumbar 
joining surface is horizontal and adjust the 
femur ball-flange screws at each hip socket 
joint to 50 inch pounds torque. Remove the 
head and the neck and install a cylindrical alu- 
minum adapter 2.0 inches in diameter and 2.80 
inches long in place of the neck. 

(3) Flex the thorax forward 50 degrees and 
then rearward as necessary to return to its ini- 
tial position in accordance with Figure 18 
unsupported by external means. 

(4) Apply a forward pull force in the 
midsagittal plane at the top of the neck adapter, 



so that at 40 degrees of the lumbar spine 
flexion the applied force is perpendicular to the 
thoracic spine box. Apply the force at any torso 
deflection rate between 0.5 and 1.5 degrees per 
second up to 40 degrees of flexion but no fur- 
ther; continue to apply for 10 seconds the force 
necessary to maintain 40 degrees of flexion, 
and record the highest applied force at that 
time. Release all force as rapidly as possible 
and measure the return angle 3 minutes after 
the release. 

§572.20 Limbs. 

The limbs consist of the assemblies shown on 
drawing SA 103C 001 as Nos. SA 103C 041, S A 
103C 042, SA 103C 051, SA 103C 052, SA 103C 
061, SA 103C 062, SA 103C 071,SA 103C 072, 
SA 103C 081, SA 103C 082, and conform to 
each of the applicable drawings listed under their 
respective numbers of the drawing SA 103C 002, 
sheets 12 through 21. 

§572.21 Test conditions and Instrumentation. 

[(a)(1) The test probe used for head and tho- 
racic impact tests is a cylinder 3 inches in diame- 
ter, 13.8 inches long and weighs 10 lbs., 6 ozs. 
Its impacting end has a flat right face that is rigid 
and that has an edge radius of 0.5 inches. 

(2) The head and thorax assembly may be 
instrumented with a Type A or Type C acceler- 
ometer. 

(i) Type A accelerometer is defined in 
drawing SA-572 SI. 

(ii) Type C accelerometer is defined in 
drawing SA-572 S2. 

(b) Head Accelerometers. Install one of the tri- 
axial accelerometers specified in §S72. 21(a)(2) on 
a mounting block located on the horizontal trans- 
verse bulkhead as shown in the drawings 
subreferenced under assembly SA 103C 010 so 
that the seismic mass centers of each sensing ele- 
ment are positioned as specified in this paragraph, 
relative to the head accelerometer reference point 
located at the intersection of a line connecting the 
longitudinal centerlines of the transfer pins in the 
side of the dummy head with the midsagittal 
plane of the dummy head. 

(1) The sensing elements of the Type C tri- 
axial accelerometer are aligned as follows: 

(i) Align one sensitive axis parallel to the 
vertical bulkhead and coincident with the 
midsagittal plane, with the seismic mass cen- 



ter located 0.2 inches dorsal to, and O.I 
inches inferior to the head accelerometer ref- ^m 
erence point. ^B 

(ii) Align the second sensitive axis with 
the horizontal plane, perpendicular to the 
midagittal plane, with the seismic mass cen- 
ter located 0.1 inches inferior, 0.4 inches to 
the right of, and 0.9 inches dorsal to the 
head accelerometer reference point. 

(iii) Align the third sensitive axis so that 
it is parallel to the midsagittal and horizontal 
planes, with the seismic mass center located 
0.1 inches inferior to, 0.6 inches dorsal to, 
and 0.4 inches to the right of the head accel- 
erometer reference point. 

(iv) All seismic mass centers are posi- 
tioned with ±0.05 inches of the specified 
locations. 

(2) The sensing elements of the Type A tri- 
axial accelerometer are aligned as follows: 

(i) Align one sensitive axis parallel to the 
vertical bulkhead and coincident with 
midsagittal planes, with the seismic mass 
center located from 0.2 to 0.47 inches dorsal 
to, from 0.01 inches inferior to 0.21 inches 
superior, and from 0.0 to 0.17 inches left of ^ 
the head accelerometer reference point. 

(ii) Align the second sensitive axis with 
the horizontal plane perpendicular to the 
medsagittal plane, with the seismic mass cen- 
ter located 0.1 to 0.13 inches inferior to, 0.17 
to 0.4 inches to the right of, and 0.47 to 0.9 
inches dorsal of the head accelerometer ref- 
erence point. 

(iii) Align the third sensitive axis so that 
it is parallel to the midsagittal and horizontal 
planes, with the seismic mass center located 
0.1 inches inferior to, 0.6 inches dorsal to, 
and 0.4 inches to the right of the head accel- 
erometer reference point, 
(c) Thorax Accelerometers. Install one of the 
triaxial accelerometers specified in § 572.21(a)(2) 
on a mounting plate attached to the vertical trans- 
verse bulkhead shown in the drawing 
subreferenced under assembly NO. SA 103C 030 
in drawing SA 103 001, so that the seismic mass 
centers of each sensing element are positioned as 
specified in this paragraph, relative to the thorax 
accelerometer reference point located in the j 

midsagittal plane 3 inches above the top surface ^J| 
of the lumbar spine, 0.3 inches doral to the accel- -^ 

erometer mounting plate surface. 



PART 572-10 



(1) The sensing elements of the Type C tri- 
axial accelerometer are ahgned as follows: 

i (i) Align one sensitive axis parallel to the 

' vertical bulkhead and midsagittal planes, 

with seismic mass center located 0.2 inches 
to the left of, 0.1 inches inferior to, and 0.2 
inches ventral to the thorax accelerometer 
reference point. 

(ii) Align the second sensitive axis so that 
it is in the horizontal transverse plane, and 
perpendicular to the midsagittal plane, with 
the seismic mass center located 0.2 inches to 
the right of, 0.1 inches inferior to, and 0.2 
inches ventral to the thorax accelerometer 
reference point. 

(iii) Align the third sensitive axis so that 
it is parallel to the midsagittal and horizontal 
planes with the seismic mass center located 
0.2 inches superior to, 0.5 inches to the right 
of. and 0. 1 inches ventral to the thorax accel- 
erometer reference points, (iv) All seismic 
mass centers shall be positioned within ±0.05 
inches of the specified locations. 

(2) The sensing elements of the Type A tri- 
axial accelerometer are aligned as follows: 

>(i) Align one sensitive axis parallel to the 
vertical bulkhead and midsagittal planes, 
with the seismic mass center located from 
0.2 inches left to 0.28 inches right, from 0.5 
to 0,15 inches inferior to, and from 0.15 to 
0.25 inches ventral of the thorax acceler- 
ometer reference point. 

(ii) Align the second sensitive axis so that 
it is in the horizontal transverse plane and 
perpendicular to the midsagittal plane, with 
the seismic mass center located from 0.06 
inches left to 0.2 inches right of, from 0.1 
inches inferior to 0.24 inches superior, and 
0.15 to 0.25 inches ventral to the thorax 
accelerometer reference point. 

(iii) Align the third sensitive axis so that 
it is parallel to the midsagittal and horizontal 
planes, with the seismic mass center located 
0.15 to 0.25 inches superior to, 0.28 to 0.5 
inches to the right of, and from 0.1 inches 
ventral to 0.19 inches dorsal to the thorax 
accelerometer reference point. (55 F.R. 
30465— July 26. 1990. Effective: August 27. 
1990)] 

I (d) The outputs of accelerometers installed in 

the dummy, and of test apparatus specified by this 
part, are recorded in individual data channels that 



conform to the requirements of SAE Rec- 
ommended Practice J211a, December 1971, with 
channel classes as follows: 

(1) Head acceleration — Class 1,000. 

(2) Pendulum acceleration^ — Class 60. 

(3) Thorax acceleration — Class 180. 

(e) The mountings for accelerometers have no 
resonance frequency less than 3 times the cut-off 
frequency of the applicable channel class. 

(0 Limb joints are set at the force between 1- 
2g, which just supports the limbs' weight when 
the limbs are extended horizontally forward. The 
force required to move a limb segment does not 
exceeed 2g throughout the range of limb motion. 

(g) Performance tests are conducted at any 
temperature from 66° F to 78° F and at any rel- 
ative humidity from 10 percent to 70 percent after 
exposure of the dummy to these conditions for a 
period of not less than 4 hours. 

(h) For the performance tests specified 
§§572.16, 572.18, and 572.19, the dummy is 
positioned in accordance with Figures 16, 17, and 
18 as follows: 

(1) The dummy is placed on a flat, rigid, 
clean, dry, horizontal surface of teflon sheeting 
with a smoothness of 40 microinches and 
whose length and width dimensions are not less 
than 16 inches, so that the dummy's midsagittal 
plane is vertical and centered on the test sur- 
face. For head tests, the seat has a vertical back 
support whose top is 12.4 ± 0.2 inches above 
the seating surface. The rear surfaces of the 
dummy's shoulders and buttocks are touching 
the back support as shown in Figure 16. For 
thorax and lumbar spine tests, the seating sur- 
face is without the back support as shown in 
Figures 17 and 18 respectively. 

(2) The shoulder yokes are adjusted so that 
they are at the midpoint of their anterior-pos- 
terior travel with their upper surfaces hori- 
zontal. 

(3) The dummy is adjusted for head impact 
and lumbar flexion tests so that the rear sur- 
faces of the shoulders and buttocks are tangent 
to a transverse vertical plane. 

(4) The arms and legs are positioned so that 
their centerlines are in planes parallel to the 
midsagittal plane. 

(i) The dummy's dimensions are specified in 
drawings No. SA 103C 002, sheets 22 through 
26. 



PART 572-1 1 



(Rev. 7/26/90) 



(j) Performance tests of the same component, (k) Surfaces of the dummy components are not 
segment, assembly or fully assembled dummy are painted except as specified in this part or in draw- 
separated in time by a period of not less than 20 ings subtended by this part, 
minutes unless otherwise specified. 



tj 



PART 572-12 



Inertial Properties of Pendulum 
Without Test Specimen. 
Weight 65.2 lbs. 

Moment of Inertia 24.5 lb. -ft. Sec. 
About Pivot Axis 



5-"/,e" Ref 




CG of Pendulum 
Apparatus Without 
Test Specimen 



Accelerometer 



Aluminum Honeycomb 
(Hexcell 1.8 Ibs./cu. ft.) 
Ref. 



CG of Test Specimen 



Plate (Sharp Edges) 

Leading Edge of Necl< 
Must Be Alligned With 
Leading Edge of Pendulum 



PART 572-Subpart C-ART PAGE 1 




mpactor Support Wire 



PART 572-Subpart C-ART PAGE 2 



Impactor Face to Be Vertical ± 2° 
at Contact of Chest 




Impactor Support Wire 




PART 572-Subpart C-ART PAGE 



.00" Radius 

I 




L7 



Pull Force in the Mid-Sagittal 
Plane Perpendicular to the Chest 
Instrument Cavity Rear Face. 



.125^ 




PART 572-Subpart C-ART PAGE 4 



Subpart D— Six-Month-Old Infant 

)§ 572.25 General Description. 
(a) The infant dummy is specified in its 
entirety by means of 5 drawings (No. SA 1001) 
and a construction manual, dated July 2, 1974, 
which describe in detail the materials and the 
procedures involved in the manufacturing of this 
dummy. 

(b) The drawings, specifications, and construc- 
tion manual referred to in this regulation that are 
not set forth in full are hereby incorporated in this 
part by reference. These materials are thereby 
made part of this regulation. The Director of the 
Federal Register has approved the materials incor- 
porated by reference. For materials subject to 
change, only the specific version approved by the 
Director of the Federal Register and specifed in 
the regulation are incorporated. A notice of any 
change will be published in the Federal Register. 
As a convenience 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. 

(c) The materials incorporated by reference are 
\ available for examination in Docket 78-09, Room 

5109, Docket Section, National Highway Traffic 
Safety Administration, 400 Seventh Street, S.W., 
Washington, D.C. 20590. Copies may be obtained 
from Rowley-Scher Reprographics, Inc., 1111 
14th Street, N.W., Washington, D.C. 20005, 
((202) 628-6667 or 408-8789). The materials are 
also on file in the reference library of the Office 
of the Federal Register, National Archives and 
Records Administration , Washington, D.C. 

(d) The structural properties of the dummy are 
such that the dummy conforms to this part in 
every respect both before and after being used in 
vehicle tests specified in Standard No. 2 1 3 of this 
chapter (§571.213). 



Subpart E— Hybrid III Test Dummy 

Source: 51 FR 26701, July 25, 1986, unless 
otherwise noted. 

Ejfective Date Note and Optional Compliance 
Provisions: At 51 FR 26701, July 25,1986, Sub- 
part E — Hybrid III Test Dummy was added, 
effective October 29, 1986. As of that date, 
manufacturers have the option of using either the 
Part 572 test dummy (Subpart B) or the Hybrid 



III test dummy until August 31, 1991. As of 
September 1, 1991, the Hybrid III will replace the 
Part 572 test dummy (Subpart B) and be used as 
the exclusive means of determining a vehicle's 
conformance with the performance requirements 
of Standard No. 208 (§571.208). 

§572.30 Incorporated Materials. 

(a) The drawings and specifications referred to 
in this regulation that are not set forth in full are 
hereby incorporated in this part by reference. The 
Director of the Federal Register has approved 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 regulation are incorporated. A 
notice of any change will be published in the 
Federal Register. As a convenience 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) The materials incorporated in this part by 
reference are available for examination in the 
general reference section of Docket 79-04, 
Docket Section, National Highway Traffic Safety 
Administration, Room 5109, 400 Seventh Street, 
S.W., Washington, D.C. 20590. Copies may be 
obtained from Rowley-Scher Reprographics, Inc., 
1216 K Street, N.W., Washington, D.C. 20005, 
((202)628-6667). The drawings and specifications 
are also on file in the reference library of the 
Office of the Federal Register, National Archives 
and Records Administration, Washington, D.C. 

§572.31 General Description. 

(a) The Hybrid III 50th percentile size dummy 
consists of components and assemblies specified 
in the Anthropomorphic Test Dummy drawings 
and specifications package which consists of the 
following six items: 

(1) The Anthropomorphic Test Dummy Parts 
List, dated [March 10, 1988], and containing 
13 pages, and Parts list Index, dated [March 
10, 1988], containing [8] pages, (57 F.R. 
479009— October 14, 1992. Effective: October 14. 
1992) 

(2) A listing of Optional Hybrid III Dummy 
Transducers, dated April 22, 1986, contain 4 
pages. 

(3) A General Motors Drawing package 
identified by GM drawing No. 78051-218 revi- 
sion R and subordinate drawings. 



PART 572-13 



(Rev. 10/14/92) 



(4) Disassembly. Inspection, Assembly and 
Limbs Adjustment Procedures for the Hybrid 
III Dummy, dated July 15, 1986, 

(5) Sign Convention for the signal outputs of 
Hybrid III Dummy Transducers, dated July 15, 
1986, 

(6) Exterior Dimensions of the Hybrid III 
Dummy, dated July 15, 1986. 

(b) The dummy is made up of the following 
component assemblies: 



Drawing 
Number 



Revi- 
sion 



78051-61 Head Assembly— Complete— (T) 

78051-90 Neck Assembly— Complete— (A) 

78051-89 Upper Torso Assembly— (K) 

Complete — 
78051-70 Lower Torso Assembly— Without (D) 

Pelvic Instrumentation Assem- 
bly, Drawing Number 78051-59 
86-5001-001 Leg Assembly— Complete (LH)— (E) 
86-5001-002 Leg Assembly— Complete (RH)— (E) 
78051-123 Arm Assembly— Complete (D) 

(LH)- 
78051-124 Arm Assembly— Complete (D) 

(RH)— 

(c) Any specifications and requirements set 
forth in this part supercede those contained in 
General Motors Drawing No. 78051-218, revision 
P. 

(d) Adjacent segments are joined in a manner 
such that throughout the range of motion and also 
under crash-impact conditions, there is no contact 
between metallic elements except for contacts that 
exist under static conditions. 

(e) The weights, inertial properties and centers 
of gravity location of component assemblies shall 
conform to those listed in drawing 78051-338, 
revision S. 

(f) The structural properties of the dummy are 
such that the dummy conforms to this part in 
every respect both before and after being used in 
vehicle test specified in Standard No. 208 of this 
Chapter (S 571.208). 

§572.32 Head. 

(a) The head consists of the assembly shown in 
the drawing 78051-61. revision T, and shall con- 
form to each of the drawings subtended therein. 

(b) When the head (drawing 78051-61, revision 
T) with neck transducer structural replacement 
(drawing 78051-383, revision F) is dropped from 
a height of 14.8 inches in accordance with para- 
graph (c) of this section, the peak resultant accel- 



erations at the location of the accelerometers 
mounted in the head in accordance with 572.36(c) ^^ 
shall not be less than 225g, and not more than ^P 
275g. The acceleration/time curve for the test 
shall be unimodal to the extent that oscillations 
occurring after the main acceleration pulse are 
less than ten percent (zero to peak) of the main 
pulse. The lateral acceleration vector shall not 
exceed 15g (zero to peak). 

(c) Test Procedure. (1) Soak the head assembly 
in a test environment at any temperature between 
66 degrees F to 78 degrees F and at a relative 
humidity from 10% to 70% for a period of at 
least four hours prior to its application in a test. 

(2) Clean the head's skin surface and the 
surface of the impact plate with 1,1,1 
Trichlorethane or equivalent. 

(3) Suspend the head, as shown in Figure 19, 
so that the lowest point on the forehead is 0.5 
inches below the lowest point on the dummy's 
nose when the midsagittal plane is vertical. 

(4) Drop the head from the specified height 
by means that ensure instant release onto a rig- 
idly supported flat horizontal steel plate, which 
is 2 inches thick and 2 feet square. The plate 

shall have a clean, dry surface and any ^ 
microfinish of not less than 8 microinches 
(rms) and not more than 80 microinches (rms). 

(5) Allow at least 2 hours between succes- 
sive tests on the same head. 

§572.33 Neck. 

(a) The neck consists of the assembly shown in 
drawing 78051-90, revision A and conforms to 
each of the drawings subtended therein. 

(b) When the neck and head assembly (consist- 
ing of the parts 78051-61, revision T; - 84; -90, 
revision A; -96; -98; -303, revision E; -305; 
-306; -307, revision X, which has a neck trans- 
ducer (drawing 83-5001-008) installed in 
conformance with 572.36(d), is tested in accord- 
ance with paragraph (c) of this section, it shall 
have the following characteristics: 

(1) Flexion, (i) Plane D, referenced in Figure 
20, shall rotate between 64 degrees and 78 
degrees, which shall occur between 57 milli- 
seconds (ms) and 64 ms from time zero. In first 
rebound, the rotation of plane D shall cross 
degrees between 113 ms and 128 ms. 

(ii) The moment measured by the neck (| 

transducer (drawing 83-5001-008) about the '^ 

occipital condyles, referenced in Figure 20, 



PART 572-14 



shall be calculated by the following formula: 
Moment (Ibs-ft) = My + 0.02875 x F,- 
where My is the moment measured in Ibs-ft 
by the moment sensor of the neck transducer 
and Fx is the force measured in lbs by the 
X axis force sensor of the neck transducer. 
The moment shall have a maximum value 
between 65 Ibs-ft occurring between 47 ms 
and 58 ms, and the positive moment shall 
decay for the first time to Ib-ft between 97 
ms and 107 ms. 

(2) Extension, (i) Plane D, referenced in Fig- 
ure 21, shall rotate between 81 degrees and 106 
degrees, which shall occur between 72 and 82 
ms from time zero. In first rebound, the rota- 
tion of plane D shall cross degree between 
147 and 174 ms. 

(ii) The moment measured by the neck 
transducer (drawing 83-5001-008) about the 
occipital condyles, referenced in Figure 21, 
shall be calculated by the following formula: 
Moment (Ibs-ft) = My + 0.02875 x Fx- 
where M is the moment measured in Ibs-ft 
by the momensensor of the neck transducer 
and Fx is the force measure measured in lbs 
by the x axis force sensor of the neck trans- 
ducer. The moment shall have a minimum 
value between -39 Ibs-ft and -59 Ibs-ft, 
which shall occur between 65 ms and 79 ms, 
and the negative moment shall decay for the 
first time to Ib-ft between 120 ms and 148 
ms. 

(3) Time zero is defined as the time of con- 
tact between the pendulum striker plate and the 
aluminum honeycomb material. 

(c) Test Procedure. (1) Soak the test material 
in a test environment at any temperature between 
69 degrees F to 72 degrees F and at a relative 
humidity from 10% to 70% for a period of at 
least four hours prior to its application in a test. 

(2) Torque the jamnut (78051-64) on the 
neck cable (78051-301. revision E) to 1.0 Ibs- 
ft ±. Ibs-ft. 

(3) Mount the head-neck assembly, defined 
in paragraph (b) of this section, on a rigid pen- 
dulum as shown in Figure 22 so that the head's 
midsagittal plane is vertical and coincides with 
the plane of motion of the pendulum's longitu- 
dinal axis. 

(4) Release the pendulum and allow it to fall 
freely from a height such that the tangential 
velocity at the pendulum accelerometer center- 



line at the instance of contact with the honey- 
comb is 23.0 ft/sec ± 0.4 ft/sec. for flexion test- 
ing and 19.9 ft/sec ± 0.4 ft/sec. for extension 
testing. The pendulum deceleration vs. time 
pulse for flexion testing shall conform to the 
characteristics shown in Table A and the 
decaying deceleration-time curve shall first 
cross 5g between 34 ms and 42 ms. The penhe 
Im deceleration vs. time pulse for extension 
testing shall conform to the characteristics 
shown in Table B and the decaying decelera- 
tion-time curve shall cross 5g between 38 ms 
and 46 ms. 

Table A 

Flexion Pendulum Deceleration vs conme Pulse 



Time (ms) 


Flesion deceleration level (g) 


10 

20 

30 

Any other time above 30 it 


22.50-27.50 

17.60-22.60 

12.50-18.50 

IS 29 maximum 


Table B 

Extension Pendulum Deceleration vs. Time Pulse 


Time ims) 


Extension deceleration level (g) 


10 
20 
30 
Any other time above 30 it 


17.20-21.00 
14.00-19.00 
11.00-16.00 
IS 22 maximum 



(5) Allow the neck to flex without impact of 
the head or neck with any object during the ts 
on 

§572.34 Thorax. 

(a) The thorax cons at of the upper torso 
assembly in drawing 78051-89, revision [K] and 
shall conform to each of the drawings subtended 
therein. 

(b) [When impacted by a test probe conform- 
ing to S 572.36(a) at 22 fps ± .40 fps in accord- 
ance with paragraph (c) ofd nos section, tthe 
borax of a complete dummy assembly (78051- 
218, Revision R) with left and right shoeg a 
51-294 and -295) removed, shall resist with a 
force of 1242.5 pounds ± 82.5 pounds measured 
by the test probe and shall have a sternum 
displacement measured relativg a spine of 2.68 
inches + 0.18 inches. The internal hysteresis in 
each impact shall be more than 69% but less than 
85%. The force measured is the product of pen- 
dulum mass and deceleration.! (53 F.R. 8755 — 
March 17, 1988. Effective: March 17, 1988) 



PART 572 



(Rev. 3/17/88) 



(c) Test procedure. (1) Soak the test dummy in 
an environment with a relative humidity from 
10% to 70% until the temperature of the ribs of 
the test dummy have stabilized at a temperature