This Standard specifies inlet and outlet connection threads, material, testing, valve spindle dimensions and operations, and marking requirements for compressed gas cylinder valves with threaded outlet connections for a nominated range of gases. It also specifies dimensional details of the outlet connecting parts.Appendix A specifies a special valve for use on small seamless gas cylinders filled with carbon dioxide and its future use is undecided (see Note 2).NOTES:1 Requirements for compressed gas cylinder valves, with a pin-indexed system of outlet connections (for medical application) or with a diameter-indexed system of outlet connections, are specified in AS 2472 and AS 2474.2 Comment is sought as to whether this special valve is relevant in today's industry.This Standard does not apply to valves for portable gas cylinders of less than 11 kg capacity for self-contained breathing apparatus, or to valves for fire extinguishers.NOTE: Comment is sought, especially from the 'self-contained breathing apparatus' (SCBA) industries, as to the relevance of this 11 kg capacity in today's industry.