(7)All chains and lifting tackles, except a rope sling, shall unless they have been subjected to such other heat treatment as may be approved by the Chief Inspector of Factories, be effectively annealed under the direct supervision of a competent person at the following intervals, namely:-(i)all chains, slings, rings, hooks, shackles and swivels used in connection with molten metal or molten slag or when they are made of half inch 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 12 months:Provided that chains and lifting tackles not in frequent use shall, subject to the Chief Inspector's approval, be annealed only when necessary and particulars of such annealing shall be entered in a register prescribed under sub-rule (5).
