The employer shall ensure at a construction site of a building or other construction work that,—
(a) all chains other than bridle chains attached to derricks and all rings, hooks, shackles and swivels, used in hoisting or lowering of such derricks, are effectively annealed under supervision of a competent person and at the following intervals, namely :—
(i) such chains, rings, hooks, shackles and swivels, which are not more than twelve-and-a-half millimetre of length, are so annealed at least once in every six months; and
(ii) all other such chains, rings, hooks, shackles and swivels are so annealed at least once in every twelve months :
Provided that such annealing as referred to in sub-clause
(i) and sub-clause (ii), shall not be required, if the Inspector, having jurisdiction, after obtaining the approval of the Chief Inspector, directs that such chains, rings, hooks, shackles and swivels undergo some other treatment and in such cases, the treatment directed by such Inspector, shall be followed :
Provided further that in case of such chains, rings, hooks, shackles and swivels, used solely on such derricks and other hoisting appliances, which are worked by hand, the provisions of sub-clause (i) and (ii), as the case may be, shall apply as if for the period of six months and twelve months the period of twelve months and two years respectively have been substituted therein :
Provided further that in case where the Inspector, having jurisdiction of the area, is of the opinion that owing to the size, design material or frequency of the use of any such chains, rings, hooks, shackles and swivels, the requirement of this clause for annealing is not necessary for the protection of building worker, he may after obtaining the approval of the Chief Inspector, certify in writing to such employer that subject to the conditions, specified in such certification, Section 40 (2) (e) 32 such chains, rings, hooks, shackles and swivels, are exempted from such annealing and thereafter, the provisions of this clause shall apply subject to such exemption :
Provided further that this clause shall not apply to—
(i) pitched chains, working on sprocket or sprocketed wheels;
(ii) rings, hooks and swivels, permanently attached to pitched chains, pulley blocks or weighing machines; and
(iii) hooks and swivels, having ball bearings or other case hardened parts;
(b) a chain or a loose gear made of high tensile steel or alloy steel is plainly marked with a mark indicating that it is so made;
(c) no chain or loose gear made of high tensile steel or alloy steel is subjected to any form of heat treatment, except where such treatment is necessary for the purpose of repair of such chain or loose gear and that such repair is made under the direction of the competent person; and
(d) the wrought iron gear the past history of which is not traceable, is suspected of being heat treated at incorrect temperature, is normalised before using it on any building or other construction work.