CGA V-9-2024

Standard for Compressed Gas Cylinder Valves

This standard defines factors that contribute to the safe design, manufacture, and use of cylinder valves for compressed gases. Compressed gases supplied in cylinders are diverse in their chemical composition and properties. Some are oxidizers, some are flammables, some are inert, etc. Gases vary in degrees of corrosivity, toxicity, and pressure and exist not only in the pure state but also in a variety of mixtures. Thus, it is a primary safety requirement of the cylinder valve that it is designed and tested for its intended use. This standard covers cylinder valve design, manufacture, and use including performance requirements such as operating temperature limits, pressure ranges, and flow capabilities. It also includes require-ments such as materials, inlet and outlet connections, cleaning, qualification and production testing, maintenance, and reconditioning. This standard also includes guidelines and requirements for the design, material selection, testing, and marking of cylinder valve protection caps. Except as noted in the last paragraph of this section, this standard is intended for valves for compressed gases packaged in U.S. Department of Transportation (DOT) and Transport Canada (TC) cylinders.  This standard provides information on valve selection, valve use guidelines, and valve protection caps (see Appendix A, Appendix B, and Section 10, respectively).