|(a) Vaporizers shall completely vaporize the LNG and heat the vapor to the appropriate temperature prior to the vapor entering the pressure regulator when the vaporizer is subjected to the maximum fuel flow rate. Vaporizers shall be permanently marked at a readily visible point with the maximum allowable working pressure of the fuel-containing portion of the vaporizer. Engine exhaust gases may be used as a direct source of heat to vaporize the fuel if the materials of construction of those parts of the vaporizer in contact with the exhaust gases are resistant to corrosion from those gases. (b) Pressure regulator inlets and chambers shall have a maximum allowable working pressure of at least the maximum allowable working pressure of the container. (c) Pressure gauges shall be designed for the pressure and temperature conditions to which they may be subjected with a burst pressure safety factor of at least four. Dials shall be graduated to read at least 1.2 times the pressure at which a pressure relief device is set to function. Gauges shall have an opening not to exceed 0.055 inches (Number 54 drill size) at the inlet connection. (d) Pipe, tubing, and fittings between the vehicular fuel container and the pressure regulator shall be designed to withstand a pressure of at least two times the maximum allowable working pressure of the container. (1) Gaskets and packing material shall be suitable for the intended service. (2) Pipe shall be stainless steel, brass, or copper, and shall comply with the following: (A) stainless steel pipe: ANSI B36.19, Specification for Stainless Steel Pipe (ASTM A 312); (B) brass pipe: ANSI H27.1, Specification for Seamless Red Brass Pipe, Standard Size (ASTM B 43); (C) copper pipe: ANSI H26.1, Specification for Seamless Copper Pipe, Standard Sizes (ASTM B 42). (3) Tubing shall be stainless steel, brass, or copper, and shall comply with the following: (A) stainless steel tubing: ANSI B31.3, Specification for Seamless and Welded Austenitic Steel Tubing for General Service (ASTM A 269); (B) copper tubing: Type K or L, ANSI H23.1, Specification for Seamless Copper Water Tube (ASTM B 88); (C) copper tubing: ANSI H23.5, Specification for Seamless Copper Tube for Air Conditioning and Refrigeration Field Service (ASTM B 280); or (D) brass tubing: ANSI H36.1, Specification for Seamless Brass Tube (ASTM B 135). (4) Pipe and tube fittings shall be stainless steel, brass, or copper. Pipe joints shall be threaded, welded, or brazed. Tubing joints shall be flared, welded, brazed, or made with tube fittings.