The standard test method is designed to produce measurement of the explosion pressure and the maximum explosion pressure of a quiescent flammable gas/air/ inert mixture in an empty closed volume at ambient temperature and pressure. In this European Standard the term “gas” includes vapours, but not mists. This European Standard does not consider mixtures that contain an increased content of oxygen; or mixtures that will react spontaneously at ambient temperature and pressure. Detonation and decomposition phenomena are not considered in this European Standard. The pressures measured by the procedures specified in this European Standard are not applicable to flameproof enclosures, that is enclosures intended to withstand an internal explosion and not to transmit it to an external explosive atmosphere, or any other closed volume where the internal geometry can result in pressure piling. Even in an enclosure of relatively simple geometry the disposition of the internal components can lead to explosion pressures significantly higher than those measured using this European Standard. Flameproof enclosures should be constructed and tested in accordance with the requirements contained in EN 50018 for electrical equipment and prEN 13463-3 for non-electrical equipment.