This standard contains specific requirements for the construction and testing of electrical equipment with the type of protection flameproof enclosure "d", intended for use in Class I, Zone 1, explosive gas atmospheres.
ANSI/ISA 60079-1-2009 history
2009ANSI/ISA 60079-1-2009 Electrical Apparatus for Use in Class I, Zone 1 Hazardous (Classified) Locations: Type of Protection - Flameproof "d"