This standard specifies the requirements for the design, construction, testing and marking of electrical apparatus with type of protection increased safety “e” intended for use in Class I, Zone 1 hazardous (classified) locations. This standard applies to electrical apparatus where the rated voltage does not exceed 11 kV r.m.s. a.c. or d.c. Additional measures are applied to ensure that the apparatus does not produce arcs, sparks, or excessive temperatures in normal operation or under specified abnormal conditions

This standard supplements and modifies the general requirements of ANSI/ISA-60079-0 Where a requirement of this standard conflicts with a requirement of ANSI/ISA-60079-0.

NOTE Increased safety “e” can provide Equipment Protection Levels (EPL) Mb or Gb. For further information, see Annex I