California Code of Regulations
Title 8 - Industrial Relations
Division 1 - Department of Industrial Relations
Chapter 4 - Division of Industrial Safety
Subchapter 4 - Construction Safety Orders
Article 32 - Oxygen, Acetylene, and Fuel Gas
Section 1743 - General Precautions

(a) No device or attachment facilitating or permitting mixture of air or oxygen with combustible gases prior to consumption, except at the burner or in a standard torch or blowpipe, shall be allowed unless approved for the purpose.

(b) Acetylene shall not be generated or utilized at a pressure in excess of 15 pounds per square inch gauge pressure.

EXCEPTION: Acetylene dissolved in suitable solvent and stored in cylinders manufactured according to Interstate Commerce Commission requirements.

(c) Oxygen cylinders and fittings shall be kept away from oil or grease. Cylinders, cylinder caps and valves, couplings, regulators, hose, and apparatus shall be kept free from oil or greasy substances and shall not be handled with oily hands or gloves. Oxygen shall not be directed at oily surfaces, greasy clothes, or within a fuel oil or other storage tank or vessel.

(d) Hose piping systems, apparatus, and fittings shall not be used.

(e) Oxygen shall never be used from a cylinder or cylinder manifold unless a pressure-reducing device intended for use with oxygen, and so marked, is provided.

(f) Acetylene shall never be brought into contact with unalloyed copper except in a blowpipe or torch.

(g) Cylinders not having fixed hand wheels shall have keys, handles or nonadjustable wrenches on valve stems while these cylinders are in service. In multiple cylinder installations only one key or handle is required for each manifold.

(h) Cylinders shall never be used as rollers or supports whether full or empty.

(i) Compressed oxygen shall not be used for ventilation, testing, or similar purposes different from its intended function in welding and burning.

(j) A dry chemical or carbon dioxide fire extinguisher rated at least 10 B:C shall be kept near operations where bottled fuel gases are being used.

(k) LP-Gas vessels shall be kept in a position so that the safety relief valve is in direct contact with the vapor space in the vessel at all times.

(l) When operations are suspended for any substantial period of time, such as during lunch or overnight, gas cylinders shall be shut off. The torch and hose shall be removed from the confined space. Upon completion or discontinuance of welding operations, the welder shall warn other workers of the location of hot metal.