1 Scope

This part of IEC 60079 contains the specific requirements for design, construction and assessment of intrinsically safe systems, Type of Protection “i”, intended for use, as a whole or in part, in locations in which the use of Group I, II or III Ex Equipment is required.

NOTE 1 This standard is intended for use by the designer of the system e.g. a person who could be a manufacturer, a specialist consultant or a member of the end-user’s staff.

This document supplements and modifies the general requirements of IEC 60079-0 and the intrinsic safety standard IEC 60079-11. Where a requirement of this standard conflicts with a requirement of IEC 60079-0 or IEC 60079-11, the requirement of this standard takes precedence.

The installation requirements of Group II or Group III systems designed in accordance with this standard are specified in IEC 60079-14.

NOTE 2 Group I installation requirements are presently not provided in IEC 60079-14. Installation requirements for Group I are being considered.

1.1 This standard contains the specific requirements for design, construction and assessment of intrinsically safe 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 NFPA 70^®, National Electrical Code^® (NEC^®).

NFPA 70^®, National Electrical Code^®, and NEC^® are registered trademarks of the National Fire Protection Association, Quincy, MA.

NOTE 1 This standard is intended for use by the designer of the system e.g. a person who could be a manufacturer, a specialist consultant or a member of the end-user’s staff.

1.2 This standard supplements and modifies the general requirements of UL 60079-0 and the intrinsic safety standard UL 60079-11. Where a requirement of this standard conflicts with a requirement of UL 60079-0 or UL 60079-11, the requirement of this standard takes precedence.

1.3 The installation requirements of Group II or Group III systems designed in accordance with this standard are specified in the NFPA 70^®, National Electrical Code^® (NEC^®).

In the US, the authority having jurisdiction for underground mines is the Mine Safety and Health Administration (MSHA) of the federal government. There are additional regulations beyond the requirements detailed here that will also apply.

1.4 Where references are made to IEC, IEC/IEEE, ISO, ISO/IEC standards, the referenced requirements found in these standards apply as modified by any applicable US National Differences for the standard (see Clause 2).