This European Standard gives requirements and the corresponding test/assessment methods applicable to leak detection kits (leak detector) based on the measurement of pressure change. Leak detection kits are intended to be used with double skin, underground or above ground, pressurized or non-pressurized, tanks or pipework designed for water polluting liquids/fluids. The kits are usually composed of:— measuring device; — evaluation device; — alarm device; — pressure generator; — pressure relief device; — liquid stop device; — condensate trap.