Explosion proof structure Classifications

The data indicated below are some of the classification specifications by structure type of the explosion proof products. Furthermore, there are mold explosion proof structure, charging explosion proof structure and special explosion proof structure.

The explosion proof classification structure is separated depending on product appplication areas.


1. Flame proof

Ex d Zone 1, 2

All electrical circuits are enclosed in a house strong enough to contain any explosion or fire that may take place on the inside.


2. Purged/Pressurized

Ex p Zone 1, 2

Type of protection in which the protective inert gas inside the enclosure is maintained at a higher pressure than that of the surrounding atmosphere.


3. Increased Safety

Ex e Zone 1, 2

Electrical circuits incorporates special measure to reduce the probability of excessive temperatures and the occurrence of arcs and sparks in normal service.


4. Non-Sparking

Ex n Zone 2

Method of protection for electrical equipment designed so that it will not ignite the surrounding explosive atmosphere in normal operation and under certain fault conditions specified in the standard.


5. Intrinsic safety

Ex i Zone 0, 1, 2

The electrical energy available in circuits and equipment, is limited to a level to low to ignite the most easily ignitable mixtures in a hazardous area.


6. Dust Explosion Proof

Ex td Zone 21, 22

The apparatus is enclosed in a manner that will exclude ignitable amounts of dusts and will not permit arcs, sparks or heat generated or liberated inside the enclosures to cause ignition of exterior dust accumulations on the enclosure or of atmospheric dust suspensions in the vicinity of the enclosure.