This standard specifies the terms and definitions related to the connection type and size of the gas cylinder valve gas outlet, the determination principle of the gas cylinder valve gas outlet, the connection type and size of the gas cylinder valve gas outlet of various gases, descriptions, etc. This standard is applicable to the cylinder valves configured on cylinders of permanent gas, liquefied gas, dissolved gas, etc. This standard does not apply to gas outlets and connections for cryogenic gas and respirator gas cylinder valves.