This European Standard specifies the general requirements and defines the testing methods for establishing oxygen compatibility of materials (metallic and non-metallic) to be used for the manufacture of cryogenic vessels and associated equipment. It mainly deals with materials that are normally or could be in contact with liquid/gaseous oxygen e.g. materials for cryogenic vessels used for the storage and/or transport of liquid oxygen. It also deals with the materials which can be in contact with oxygen enriched environment e.g. insulating materials used for nitrogen, neon, hydrogen and helium cryogenic vessels where air condensation is possible.