ISA 12.00.01

This standard specifies the general requirements for construction, testing and marking of electrical apparatus, Ex cable entries and Ex components, intended for use in potentially explosive atmospheres of gas, vapor and mist defined as Class I, Zone 0, 1 or 2 by the National Electrical Code, NFPA 70.

Apparatus covered by this standard and the associated standards noted below shall also comply with the applicable requirements for similar apparatus for use in unclassified locations. A list of commonly applied standards is shown in informative Annex E.

NOTE Requirements for safety of electrical equipment in ordinary (unclassified) locations can be found in ANSI Standards, NEMA Standards, Federal Regulations, etc.

This standard is supplemented or modified by the following standards concerning specific types of protection:

• Flameproof enclosures `d', (ANSI/ISA-12.22.01-2002 [IEC 60079-1 Mod]);

• Pressurized enclosures `p', see Note 3;

• Powder-filling `q', (ANSI/ISA-12.25.01-1998 [IEC 60079-5 Mod]);

• Oil-immersion `o', (ANSI/ISA-12.26.01-1998 [IEC 60079-6 Mod]);

• Increased safety `e', (ANSI/ISA-12.16.01-2002 [IEC 60079-7 Mod]);

• Intrinsic safety `i', (ISA-12.02.01 [IEC 60079-11 Mod]);

• Encapsulation `m', (ANSI/ISA-12.23.01-2002 [IEC 60079-18 Mod]).

This standard and the above documents are not applicable to the construction of electromedical apparatus, shot-firing exploders, test devices for exploders and for shot-firing circuits.

This standard is not applicable to electrical resistance heat tracing cables. The requirements for electrical resistance heat tracing cables are located in IEEE 515, Standard for Testing, Design, Installation, and Maintenance of Electrical Resistance Heat Tracing for Industrial Applications and supercede those of ANSI/ISA-12.16.01-2002 (IEC 60079-7 Mod). All components of a heat tracing system intended to be in a hazardous (classified) location, that are not covered by IEEE 515, shall be evaluated using this standard and the applicable sub-parts.

NOTE 1 Components such as power connections, splices, end terminations, as well as cable entries, fittings, and seals are to be evaluated according to the type of protection employed.

NOTE 2 In addition to the types of protection listed above, (ISA-12.12.02-2002) is applicable for use in potentially explosive atmospheres.

NOTE 3 The requirements for pressurization can be found in ANSI/NFPA 496, "Pressurized Enclosures for Electrical Equipment," along with additional guidance in ISA-RP12.4-1996, "Pressurized Enclosures."