MT 60079-26 - TC 31/MT 60079-26

IEC 60079-26:2021 specifies requirements for construction, testing and marking for Ex Equipment that contains parts of the equipment with different Equipment Protection Levels (EPLs) and a separation element. This equipment is mounted across a boundary where different EPLs are required, for example between different gas hazardous areas, dust hazardous areas or gas hazardous areas adjacent to dust hazardous areas.
Separation elements are considered for both electrical and non-electrical equipment. If mechanical energy can be transformed into a potential ignition source, additionally an ignition hazard assessment in accordance with ISO 80079-36 is performed and appropriate measures are undertaken.
This document also specifies requirements for the combination of two Types of Protection, each with EPL Gb, to achieve EPL Ga.
This document supplements and modifies the general requirements of IEC 60079-0. Where a requirement of this document conflicts with a requirement of IEC 60079-0, the requirement of this document takes precedence. This fourth edition cancels and replaces the third edition and constitutes a technical revision.
Please see the IEC 60079-26:2020 foreword for a description of the main changes with respect to the previous edition.

IEC 60079-26:2014 is available as IEC 60079-26:2014 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.
IEC 60079-26:2014 specifies alternative requirements for construction, test and marking for electrical equipment that provides Equipment Protection Level (EPL) Ga when single standardised Types of Protection (e.g. Ex "ia", Ex "ma", Ex "da") cannot be applied. This standard also applies to equipment mounted across a boundary where different Equipment Protection Levels may be required. This electrical equipment, within the operational parameters specified by the manufacturer, ensures a very high Level of Protection that includes rare malfunctions related to the equipment or two malfunctions occurring independently of each other. This standard supplements and modifies the general requirements of IEC 60079-0. Where a requirement of this standard conflicts with a requirement of IEC 60079-0, the requirement of this standard takes precedence. This third edition cancels and replaces the second edition published in 2006 and constitutes a technical revision. The numerous changes are identified in the Foreword of the document. Keywords: Equipment Protection Level (EPL) Ga