Flame proof casings

"Flameproofing" or, better, "explosionproof" protection as a concept relates to the enclosure within which equipment is placed.

• A Flameproof enclosure is constructed so as to withstand the force of an internal explosion without rupture, should one occur, and not transmit the flame of the explosion to the surroundings, while maintaining the temperature class rating at the surface of the enclosure during the internal explosion.

This type of equipment is type-tested and certified in accordance with national and international codes. Care must be taken in selecting equipment that is used in one country as it may not necessarily be approved for use in other countries.

A Flameproof enclosure usually requires tools other than commonplace ones (like a simple screwdriver or adjustable spanner) to open it.

The concept of flameproofing requires also all cable entries to be flameproof as well, and the special glands so used will also have a flameproof type test certification, rendering the whole assembly flameproof according to the concept.

National codes will determine where flameproof equipment is required. In the UK it can be installed in explosion-hazardous areas Zone 2 and Zone 1. It is labelled "Ex d" or "EEx d". "Ex" indicates hazardous area equipment in the UK, "d" indicates the flameproof concept of explosion protection, and "EEx" indicates equipment that is certified to harmonised European standards.

There is no requirement for flameproof equipment to continue to operate during a fire. If there happens to be a fire, then there is a much bigger problem to deal with than continuing the operation of the flameproof equipment!!

A training course on the use of electrical equipment in hazardous areas is well worth signing up for, and is recommended.