API RP 54 Section 20 - Hotwork, Welding, and Flame Cutting Operations
20.1.1 A written safety work permit system covering welding and flame cutting operations shall be observed on all drilling and service rigs.
20.1.3 Welding and flame cutting operations shall not be permitted close to flammable liquids, accumulations of crude oil, escaping gas, or locations where sparks, flames, heat, or hot slag could be sources of ignition.
20.1.4 Certified welders shall perform welding or flame cutting operations on surface facilities, piping, and equipment for which the primary function is to contain hydrocarbons.
20.4.1 Apparatus such as torches, regulators, hoses, and arc welding machines shall be in good operating condition and repair. Only approved oxygen and acetylene cylinders shall be used.
20.4.2 Oxygen and acetylene torches should be equipped with flash-back arrestors.
20.4.3 All cylinders with a water weight capacity of over 30 pounds shall be equipped with a valve protection cap, a collar, or recess to protect the valve. Valve caps shall be in place except when cylinders are connected for use.
20.4.4 Cylinders shall be stored in assigned places away from elevators, stairs, or walkways. They shall be secured to prevent accidental overturning.
20.4.5 Cylinders shall not be kept in unventilated enclosures, such as lockers and cupboards.
20.4.6 Oxygen cylinders in storage shall be separated from fuel gas cylinders or combustible materials a minimum distance of 20 ft (6.1 m) or by a noncombustible barrier at least 5 ft (1.5 m) high.
20.4.7 Acetylene cylinders shall be stored valve end up with protective caps affixed and properly secured. When a job using acetylene devices is completed or prior to transporting acetylene cylinders, the valve on the acetylene cylinder shall be closed and pressure on the hoses bled to zero.
20.4.8 When transporting cylinders by a crane or derrick, a cradle, bin, or other suitable platform shall be used. Slings shall not be used. Also, cylinders shall not be dropped, struck, or permitted to strike each other.
20.4.9 On arc welding machines, the control apparatus shall be enclosed except for the operating wheels, levers, or handles.
20.4.10 Input power terminals, top charge devices, and electrically energized metal parts shall be completely enclosed and accessible only by means of tools.
20.4.11 Terminals from welding leads shall be protected from accidental contact by personnel or metal objects.
20.4.12 The frame or case of an electrically driven arc welding machine shall be grounded.
20.4.13 Cables with splices within 10 ft (3.1 m) of the holder shall not be used. The welder should not coil or loop welding electrode cables around parts of his body.
20.5 Welding Fumes and Ventilation