ISO 23551-10:2016 specifies the safety, design, construction and performance requirements and testing for automatic vent valves (hereafter referred to as "valves") for use with gas burners, gas appliances burning one or more gaseous fuels. It is applicable to valves with declared maximum inlet pressures up to and including 500 kPa (5 bar) of nominal connection sizes up to and including DN 100 (4"). It is applicable to - normally open valves, - electrically operated valves and to valves actuated by fluids where the control valves for these fluids are actuated electrically, but not to any external devices for switching the control signal or actuating energy, and - valves fitted with open position indicator switches. It is not applicable to - valves for burners and appliances using renewables and/or waste gases (i.e. gases having corrosive characteristics), In case valves are in contact with renewables and/or waste gases, it is recommend to use ISO 23551-10:2016 only if explicit information is provided and relevant test methods and requirements are specified. - valves for appliances intended to be installed in the open air and exposed to the outdoor environment, - valves that are connected directly to mains pipe-work or to a container that maintains a standard distribution pressure, and - valves suitable with oil. It is applicable to type testing only.