ANSI/ISA 60079-25 (12.02.05)-2011
This standard contains the specific requirements for construction and assessment of intrinsically safe electrical systems, type of protection i, intended for use, as a whole or in part, in Class I, Zone 0, 1, or 2, or Zone 20, 21, or 22 hazardous (classified) locations as defined by the National Electrical Code (NEC), ANSI/NFPA 70.