This standard specifies the particular requirements for construction, test and marking for electrical equipment of Group II intended for use in Class I, Zone 0 as defined in the National Electrical Code, ANSI/NFPA 70. This electrical equipment, within the operational parameters specified by the manufacturer, ensures a very high level of protection that includes rare faults related to the equipment or two faults occurring independently of each other.
ANSI/ISA 60079-26-2011 history
2011ANSI/ISA 60079-26-2011 Explosive Atmospheres - Part 26: Equipment for Use in Class I, Zone 0 Hazardous (Classified) Locations