BS EN 60079-26:2015

What is BS EN 60079-26 - EA equipment protection level Ga standard about?

Dusts, as defined in this standard, are hazardous because when they are dispersed in air by any means they may form potentially explosive atmospheres. Furthermore, layers of dust may ignite and act as ignition sources for an explosive atmosphere. IEC 60079-26 contains specific 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. IEC 60079-26, also applies to equipment mounted across a boundary where different Equipment Protection Levels may be required.

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.

Who is BS EN 60079-26 - EA equipment protection level Ga standard for?

BS EN 60079-26 on EA equipment protection level Ga standard is useful for:

• Manufacturers of high voltage equipment
• Operators in high voltage areas
• Concerned maintenance teams
• Product development teams
• Quality control teams

Why should you use BS EN 60079-26 - EA equipment protection level Ga standard?

Parts which might ignite an explosive atmosphere are immersed in oil or other non-flammable, insulating liquid so that gases and vapours above the oil level and outside the enclosure cannot be ignited by electric arcs or sparks generated below the oil level, or by hot residual gases from the switching process or by hot surfaces – e. g. on a resistor. BS EN 60079-26 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. BS EN 60079-26 also specifies requirements for the combination of two Types of Protection, each with EPL Gb, to achieve EPL Ga. The sections on levels Requirements for design and construction, Equipment with moving parts, type tests, marking and instructions have been discussed in thorough details in BS EN 60079-26. Using BS EN 60079-26 guidelines, you can construct, mark and test Ex equipment and avoid any sort of hazards including explosion, fire, and electrical hazards.

What’s changed since the last update?

BS EN 60079-26:2015 supersedes BS EN 60079-26:2009. BS EN 60079-26:2015 includes some technical and editorial changes with respect to BS EN 60079-26:2009. These include:

• Requirements against mechanical and electrostatic ignition hazards deleted (now covered in EN 60079-0) Additional requirements have been introduced for the protective liquid
• Requirement for separation element detailed regarding external influences
• Intrinsic safety Ex ia as single type of protection including associated apparatus deleted (now covered by EPL)
• Conditions a) and b) linked with an “and”, therefore requirement of “flameproof joint” deleted in following clause. Both requirements already covered by separation elements and standardised process connections.
• Process connection requires a sufficiently tight joint: IP66 added alternatively to IP67.