QUADRENNIAL SURVEYS

567

Multiple Shea,\o Block \vith safe woik-	"]
ing  load  over  20  tons  up  to  and	±	20 tons in excess of the safe
including 40 tons	J                    working load
Multiple Sheave Block with safe work-	I	One and a half times the safe
ing load over 40 tons                         . .                           working load.
Provided that where the Chief Inspector of Factories is of opinion that,
owing to the size, design, construction, material or use of any such loose gear
or class of such gear, any of the above requirements are not necessary for the
protection of persons employed, he may by certificate hi writing (which he may
in his discretion revoke) exempt such gear or class of gear from such requirement
subject to such conditions as may be stated in the certificate.
 (d)	After being tested as aforesaid, all machines \vith the whole of the
gear accessory thereto and all loose gear shall be examined, the sheaves and
the  pins of the pulley blocks being removed for the purpose, to see that no
part is injured or permanently deformed by the test.
 (e)	In the case of wire ropes, a sample shall be tested to destruction and
the safe working; load shall not exceed one-fifth of the breaking load of the
sample tested.
CLASSIFICATION   SURVEYS.
To receive the distinctive mark 100 Al in Lloyd's Register,
the vessel must be surveyed periodically. Surveys become due at
4 years (No. 1 Survey), 8 years (No. 2 Survey) and 12 years (No. 3
Survey) from the date of build, a year's grace being permitted in
which to complete the survey. The conditions of survey are as
follows:—
SPECIAL  SURVEY  No. 1.
 1.	The vessel is to be placed on blocks of sufficient height in a
dry dock, or on a slipway; proper stages are to be made, and the
holds and peaks are to be cleared for examination.
 2.	In vessels having a single bottom the Umber boards and
ceiling equal to not less than two strakes fore and aft on each side
are to be removed, one such strake being taken from the bilges.
Where the ceiling is fitted in hatches, the whole of the hatches and
one strake of ceiling at the bilges are to be removed.
 3.	The coal bunkers of steam vessels are to be cleared for
examination, and ceiling is to be removed as in the holds.   The
bilges and limbers all fore and aft are to be cleaned out, so as to
allow of these parts being properly examined.
 4.	The framing and both surfaces of shell plating are to be