What is Explosion Proof Lighting?

Explosion Proof Lighting is a light fixture that has the unique ability, in case of an internal explosion, to contain this event inside the fixture. If a spark creates an explosion inside an explosion proof fixture, the fixture is designed not to transfer this explosion to its external environment. Explosion proof lighting is all about containment. That is why they are extremely robust fixtures with thick metal walls and glass.

Lights that are Explosion Proof rated are certified and tested and must pass a specific standards to ensure they are safe. The most common classes are Class 1 Division 1 and Class 1 Division 2.

The major difference between these two classes is the existence of combustible materials in the surrounding environment. In Class 1 Division 1 environments, these gases, vapors or materials are commonly present. In Class 1 Division 2 environments, these same explosive materials, gases or vapors are present at times but not all the time.

What is Intrinsically Safe Lighting?

Intrinsically Safe Lighting is also considered Explosion Proof Lighting. The main difference between the two is that what we consider to be explosion proof lighting ‘contains’ the explosion within the fixture. Intrinsically safe lighting is a fixture designed in such a manner to prevent an explosion or a set of conditions that would cause an explosion. So an intrinsically safe light is designed so that its theoretically incapable of creating an explosion. Therefore, its fixture is not designed to contain it.

Intrinsically Safe Lighting tends to be low voltage / low power lighting, but its not necessarily so. It is however easier to create an intrinsically safe low voltage and low power light than a high voltage / high power light. That is why most high power led fixtures are explosion proof fixtures and not intrinsically safe fixtures. Many intrinsically safe lights are battery powered.

What is Vapor Proof Lighting?

Vapor Proof lighting are lights that are sealed so that the environment that exists on the exterior of the fixture does not enter the fixture itself. The environment is not necessarily explosive in nature, but could be damaging to the light components if they entered the fixture. There are gases that are corrosive but not necessarily explosive. Vapor proof lights are designed to keep out both dust, vapors, gases and / or particles as well as water / moisture.

Is Vapor Proof Lighting Explosion Proof?

A vapor proof light is not an explosion proof light. While it is true it is designed to keep vapors, gases and materials from entering inside the fixture, that is not the criteria that makes a vapor proof light explosion proof.

You should never use a vapor proof light to replace an explosion proof light or an intrinsically safe light. A vapor proof light can neither contain an explosion nor is it designed to prevent an explosion.

 Is Explosion Proof Lighting Vapor Proof?

It can be, but not necessarily so. It is actually common for explosion proof lights to allow the outside environment inside the fixture. And yes, that means explosive gas, vapors and materials. But by design, these lights contain or prevent an explosion from happening. So being vapor tight is not the goal of a explosion proof. But it doesn’t mean that an explosion proof light can’t be vapor proof.

However, if you require a vapor proof fixture, it is far most cost effective to purchase a vapor tight fixture, and not an explosive proof fixture that is vapor tight as well.