This standard specifies requirements for the construction, testing and marking for Group II electrical apparatus with type of protection, “n” intended for use in Class I, Zone 2 hazardous (classified) locations as defined by the National Electrical Code® (NEC®), ANSI/NFPA 70.

This standard is applicable to non-sparking electrical apparatus and also to electrical apparatus with parts or circuits producing arcs or sparks or having hot surfaces which, if not protected in one of the ways specified in this standard, could be capable of igniting a surrounding explosive gas atmosphere. This standard describes several different methods by which this can be achieved which may be combined with other methods described in ANSI/ISA-60079-0.

This standard supplements the general requirements in ANSI/ISA-60079-0.

NOTE 1 A non-incendive component is limited in use to the particular circuit for which it has been shown to be nonignition capable and, therefore, cannot be separately assessed as complying with this standard.

NOTE 2 Compliance with this standard does not imply any removal of, or lowering of the requirements of any other standard with which the electrical apparatus complies.

NOTE 3 This part supplements, and may enhance, the requirements for apparatus for normal industrial applications. Where compliance with other IEC standards is indicated, such as IEC 60034 for motors and IEC 60598-2 for luminaires, proving compliance to those standards is normally the responsibility of the manufacturer.

NOTE 4 The National Electrical Code^® (NFPA 70^®) through the 2008 edition only recognizes types of protection “nA”, “nC” and “nR” and not “nL”. See note in 35.1.

This report specifies requirements for the construction, assessment and testing of electrical apparatus with type of protection “n” which, when operating normally within its rated duty, is unlikely to be capable of igniting a surrounding explosive gas atmosphere.

This report specifies the features of apparatus which shall be assessed to achieve a satisfactory level of safety for electrical apparatus for use in Zone 2.

This report applies only to Group II electrical apparatus intended for use in locations with explosive gas atmospheres other than in mines subject to firedamp.

The requirements of ANSI/ISA-60079-0 do not apply to electrical apparatus with type of protection “n” unless otherwise specified in this document.

NOTE 1 – This report does not prohibit the use of electrical apparatus complying with the requirements of a recognized standard for industrial electrical apparatus which does not in normal service produce arcs or sparks or ignition-capable hot surfaces. (See IEC Publication 79-14.)

NOTE 2 – This report is worded in the mandatory form because it was intended to be a “Standard”. It is up to each National Committee, when drafting a similar document based on this report, to decide which form of wording to use in their national standard or report.