ISO 23551-5:2014

ISO 23551-5:2014 specifies safety, constructional and performance requirements for manual gas valves intended for use with gas burners and gas-burning appliances, hereafter referred to as ?valves', unless otherwise specified.
ISO 23551-5:2014 applies to following types of manual gas valves:

manual gas shut-off valve;
gas burner valve;
appliance connector valve;
"delta C" valve.

ISO 23551-5:2014 applies to valves for gas burners and gas-burning appliances of nominal connection size up to and including DN 100 that can be used and tested independently of these appliances using fuel gases, as natural gas, manufactured gas or liquefied petroleum gas (LPG) at inlet pressures up to and including 500 kPa. It is not applicable to corrosive and waste gases.
ISO 23551-5:2014 covers type testing only.