Specifies general requirements for construction, testing andmarking of electrical apparatus for explosive gas atmospheres.Applies to electrical apparatus where atmospheric conditions forthe explosion characteristics of the explosive gas atmosphere areconsidered as having pressures in the range 80 kPa (0.8 bar) to 110kPa (1.1 bar) at a temperature in the range -20°C to +60°C.Atmospheric conditions outside this range may need specialconsideration.Does not apply to devices whose stated electrical parameters do notexceed any of the values 1-2 V, 0.1 A, 20 µJ or 25 mW, which neednot be certified or marked as required by IEC 79. However, suchdevices are subject to the requirements of the various parts of IEC79 if they are connected to a device which contains a source or astorage element of electrical energy which could cause the circuitto exceed these parameters.Supersedes IEC 79-8 and 79-9.