This European Standard specifies the requirements for the design, manufacture and testing of valves for cryogenic service, i.e. for operation with cryogenic fluids (as defined in EN 1251-1) below - 10 °C as well as at ambient conditions to allow for start-up and run-down. It specifies additional requirements for cryogenic service for the appropriate valve product standard. NOTE a cryogenic fluid (refrigerated liquefied gas) is a gas which is partially liquid because of its low temperature (including totally evaporated liquids and supercritical fluids). It applies to sizes up to DN 150 including vacuum jacketed cryogenic valves. This European Standard is not applicable to safety valves and valves for liquefied natural gas (LNG). It is intended that the valve be designed and tested to satisfy a pressure rating (PN or Class). Valves may then be selected with a PN or Class equal to or greater than the maximum allowable pressure (PS) of the equipment with which it is to be used.