Gives guidance on the design, selection and erection of electrical installations in areas where explosive gas atmospheres could occur.Applies to all permanent electrical installations within the scope of IEC 364-1. However, may be applied, where appropriate, to electrical installations with voltages higher than the upper limit of IEC 364-1, namely 1 000 V a.c. Wherever possible the recommendations given should also be applied to temporary electrical installations, such as experimental prototype or pilot industrial installations. This publication has the status of a technical report.