Nov. 21.] THE NEW ZEALAND GAZETTE. 3341

(10) The jib of a “Scotch” derrick crane shall not be—
(a) Erected between the backstays of the crane :
(b) Lengthened unless all other members are lengthened in the
same proportion. In all such cases the approval of the
Inspector shall first be obtained.
Any load which lies in the angle between the backstays of a crane
shall not be moved by that crane.
(11) On every stage, gantry, or place on which a crane moves an
unobstructed passageway at least two feet in width shall be maintained
at every position of the crane (a) between the cab or any other part
of the crane and the edge of such stage, gantry, or place, and (b) between
any part of the crane and any material near the crane or crane-track.
(12) All rails on which a travelling crane moves shall be—
(a) Of adequate section and have an even running surface :
(b) Secured by fish-plates and fastened to sleepers.
(13) The whole track, whether on the ground or raised, shall be
properly laid, and any supports shall be of sufficient strength and
maintained in good condition.

HOISTS FOR BUILDING OPERATIONS.

9. (1) The timber used in the construction of hoist-towers shall
   be of the best approved kind, well-seasoned, and free from knots
   and other defects.
   (2) A tower, the outside dimensions of which do not exceed 5 ft.
   by 5 ft., shall be constructed as follows :—
   (a) The corner posts shall be not less than 4 in. by 4 in. cross-
   sectional dimensions if in one piece of timber, but if such corner posts
   are built up of two pieces of timber each shall be not less than 5 in. by
   2 in.
   (b) The corner posts shall be framed together at each side of the
   tower with horizontal and diagonal braces. The distance between
   the centres of the horizontal braces shall not exceed 5 ft. There
   shall be one diagonal brace between every two horizontal braces.
   The dimensions of the braces shall be not less than 5 in. by 2 in., and
   shall be connected to the corner posts by bolts not less than ½ in.
   in diameter.
   (c) If timber is used for the supporting beams of the towerhead
   rope-sheaves, such timber shall be hardwood and each beam shall be
   not less than 6 in. by 4 in.
   (d) If a hoist-tower is set up within or contiguous to a building it
   shall be securely fastened to the building at each floor. If set up in
   any other position it shall be kept upright by steel-wire guy ropes.
   One set of four guy ropes shall be used for every 30 ft. of the height of
   the tower. The anchorages for the guys shall be so spaced that the
   guys shall be not more than 90 degrees apart in plan.
   (e) Ladders shall be used as a means of access to the towerhead,
   and landing platforms shall be constructed every 30 ft. or such lesser
   distance as may be necessary to the satisfaction of the Inspector.

PLATFORM HOISTS.

10. (1) The parts of a builder’s hoist frame structure including
    the platform and supports for the overhead rope-sheaves shall be
    constructed to carry a maximum load greater by 25 per cent. than the
    load proposed to be carried.
    (2) The platform shall be arranged to operate between vertical
    guides which shall be secured to the floors, framework, or other
    structure surrounding them to the satisfaction of the Inspector.
    (3) Lifts shall be fitted with a safety catch to prevent the
    moving of the platform while loading or unloading.
    (4) Timber guard-rails of not less than 3 in. by 2 in. shall be
    provided across all openings giving access to a hoist platform and
    shall be fixed at a height of 3 ft. above the landing.
    (5) An efficient and safe signalling arrangement shall be provided
    for the purpose of directing the driver of such platform hoist when
    to raise, lower, or stop the hoist.
    (6) No person shall be, and no owner or person in charge shall
    permit any person to be, on a platform hoist while it is in motion.
11. (1) Hoist-rope sheave-spindles shall be fitted with block
    bearings, the latter to be provided with lubricating devices.
    (2) No hoist-rope sheave or pulley, the flange, rim-arm, or boss
    of which is broken, shall be used.