Section 296-307-44017 - Piping, valves, and fittings(1) Piping may be underground, aboveground, or a combination of both. It must be well supported and protected against physical damage and corrosion.(2) Piping laid beneath driveways must be installed to prevent physical damage by vehicles.(3) Piping must be wrought iron or steel (black or galvanized), brass or copper pipe; or seamless copper, brass, or steel tubing and must be suitable for a minimum pressure of 250 psig. Pipe joints may be screwed, flanged, brazed, or welded. The use of aluminum alloy piping or tubing is prohibited.(4) All shut-off valves (liquid or gas) must be suitable for LP-gas service and designed for at least the maximum pressure to which they may be subjected. Valves that may be subjected to container pressure must have a rated working pressure of at least 250 psig.(5) All materials used for valve seats, packing, gaskets, diaphragms, etc., must be resistant to the action of LP-gas.(6) Fittings must be steel, malleable iron, or brass having a minimum working pressure of 250 psig. Cast iron pipe fittings, such as ells, tees and unions must not be used.(7) All piping must be tested after assembly and proved free from leaks at least at the normal operating pressures.(8) The employer must allow for expansion, contraction, jarring, and vibration, and for settling. The employer may use flexible connections.Wash. Admin. Code § 296-307-44017
Amended by WSR 20-21-091, Filed 10/20/2020, effective 11/20/202097-09-013, recodified as § 296-307-44017, filed 4/7/97, effective 4/7/97. Statutory Authority: RCW 49.17.040,[49.17.]050 and [49.17.]060. 96-22-048, § 296-306A-44017, filed 10/31/96, effective 12/1/96.