(6)All chains and lifting tackle, except a rope sling shall, unless they have subjected to such other heat treatment, as may be approved by Chief Inspector of Factories be effectively annealed under the supervision of a competent person at the following intervals:(i)all chains, slings, rings, hooks, shackles, swivels used in connection with molten metal or molten slag or when they are made of I /2inch bar or smaller, once at least in every six months,(ii)all other chains, rings, hooks, shackles and swivels in general use, once at least in every twelve months:Provided that chains and lifting tackle not in frequent use, shall subject to the Chief Inspector's approval, be annealed only when necessary. Particulars of such annealing shall be entered in a register prescribed under sub-rule (3).
