An explosion-proof enclosure is an enclosure that will withstand an internal explosion of gas or vapour without rupture and without causing the ignition of an external gas or vapour. It is important to remember that EXPLOSION-PROOF DOES NOT MEAN WATERPROOF.
To prevent the ignition of an external explosive atmosphere, the enclosure must not only be strong enough to withstand the internal explosion pressure, but all of the openings (e.g. cover joints, conduit or cable entries, operating shafts, etc.) must be tight enough to cool the hot burning gases before they can come into contact with the external atmosphere.
