(1) You must ensure that all timbers for "A" frames are of correct size, length, and condition to sustain the maximum contemplated loads.
(2) You must ensure that "A" frame timbers are braced with two spreaders spaced one-quarter the length of the "A" frame from each end. Cross bracing must cross between the two spreaders. Bracing material must be not less than 2/3rds of the rated strength of the "A" frame timbers.
(3) You must use tie rods (staybolts) of not less than 1/12th the diameter of the main "A" frame timbers. You must place tie rods directly above the upper spreader and directly below the lower spreader. Ends of bolts must be secured at each end with malleable washers and nuts.
(4) You must securely anchor the base of the "A" frame. You must set elevating type "A" frames in pinion-type sockets. You must securely anchor pinion bases.
(5) You must ensure that guy lines are of sufficient strength to carry the load imposed upon them and they must be securely fastened in place.
[Statutory Authority: RCW
49.17.010,
49.17.040,
49.17.050, and
49.17.060. WSR 15-24-100, § 296-24-293, filed 12/1/15, effective 1/5/16; Order 73-5, § 296-24-293, filed 5/9/73 and Order 73-4, § 296-24-293, filed 5/7/73.]