.-(1) Valves fitted to gas cylinders shall comply in all respects with the following specifications, namely:-(a)in respect of industrial gas cylinders, IS: 3224;(b)in respect of medical gas cylinders, IS: 3745;(c)in respect of cylinders used with breathing apparatus, IS: 7302 as amended from time to time;(d)in respect of cylinders used for filling liquefied petroleum gas, IS: 8776 for cylinders of water capacity not exceeding 5 litres and, IS: 8737 for cylinders of water capacity exceeding 5 litres;(e)in respect of auto LPG containers, IS: 15100;(f)in respect of small Refrigerant cylinders, IS: 12300:Provided that the Chief Controller may, if he is of opinion that it is necessary so to do in the public interest, permit the use of valves not conforming to any of the above specifications.(2)Valves fitted to Carbon dioxide cylinders shall be provided in the body with a safety release consisting of softened copper disc so arranged as to burst at a pressure between 200 kg/cm2 and 220 kg/cm2.(3)Valves for cylinders containing flammable gases not listed in IS: 3224 shall have outlets provided with left handed screw threads for the pipes or other connections.(4)All other valves shall have outlets with right handed screw threads.(5)The valves shall be attached to the cylinder neck by screwing and not by making any permanent attachment or inserting adapter in between.(6)The design of spindle-operated valves shall be such that when fitted to the cylinders it shall not be possible to withdraw the spindle under normal operating conditions.
