Flameproof vs Explosion Proof

Difference between Flame proof and Explosion proof

Flame proof and Explosion proof enclosures are designed to prevent ignition and explosions emanating from some gases. These enclosures are made of metallic material which is strong enough to withstand pressure forces caused by the gases. They are designed with joints which cool the gases down thus doing away with the danger of these hot gases igniting more volatile gases in unsafe places.

Flame proof enclosures

The  use of flame proof enclosures is  guarded by the IEC which recommends laboratory test of the enclosures so as to attain a minimum factor of safety of 1.5,where it is given by the following formula .factor of safety=actual pressure withstanding capacity/maximum  pressure released in  an explosion. On passing the test, special devices are used to firmly fix them in such a way that, they can only be dismantled using special tools or even sometimes sophisticated set of tools.

Explosion proof

The use of explosion proof enclosures is most common in the United States and Canada. Unlike in the flame proof where factor of safety is set to 1.5, in the explosion proof a greater factor of safety of 4 is recommended to manufacturers. This results in the explosion proof enclosures being more heavily constructed than the flame proof. Drilling of explosion proof enclosures in the field is also acceptable.

Differences between flame proof and explosion proof enclosures

To some extend flame proof and explosion proof enclosures are similar but they do as well differ in some ways. For instance talking about how they are fixed, we find that both of them have their covers for the tops fixed by using bolts which are screwed to the threaded tops. Nevertheless the flame proof enclosures also have some special devices just to hold them firm whereas it’s not the case with the explosion proof enclosures. The other very important difference between the two is that unlike the flame proof enclosures which can only be drilled in the factory, the explosion proof can also be drilled in the field hence making them easier to use by OEM’s.

The choice on which protection to use will depend on the user’s preference and the use for which he or she needs it.

In brief

Flame proof enclosures are given a safety factor of 1.5 while the explosion proof enclosures are given a safety factor of 4.

The flame proof enclosures can only be drilled in the factory while the explosion proof can be drilled in the field making them easy to use by OEM’s.


  • egera

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