UL 60079-26 PDF

1 Scope

This

part of IEC 60079

standard

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.

EXAMPLE: Equipment installed in the wall of a storage vessel containing Zone 0 (requiring EPL Ga) inside an area defined as Zone 1 (requiring EPL Gb).

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.

NOTE A malfunction may result from a failure of the component parts of the electrical equipment or from anticipated externally applied influences. Two independent malfunctions which may occur more frequently and which, separately, would not create an ignition hazard but which, in combination, could create a potential ignition hazard, are regarded as occurring together to form a rare malfunction.

This standard supplements and modifies the general requirements of

IEC 60079-0

UL 60079-0

. Where a requirement of this standard conflicts with a requirement of

IEC 60079-0

UL 60079-0

, the requirement of this standard takes precedence.

Where references are made to IEC 60079 standards, the referenced requirements found in these standards shall apply as modified by any applicable U.S. National Differences.

Summary of Topics

This revision of ANSI/UL 60079-26 dated August 16, 2022 is being issued to update the title page to reflect the most recent designation as a Reaffirmed American National Standard (ANS). No technical changes have been made.

Please note that the national difference document incorporates all of the US national differences for UL 60079-26. UL 60079-26 is based on IEC 60079-26, Edition 3, published October, 2014.