Consider, for example, that traditional metal halide or high pressure sodium light fixtures contain bulbs that have a pressurized internal atmosphere. If the bulb’s glass casing is damaged in any way so as to elicit an electric spark to the open air, it could could ignite flammable substances in the environment, particularly if those fixtures are installed in an area that is designated as a “hazardous location,” where the atmosphere around the light might include concentrations of flammable vapors, dusts, or fibers. A spark in an electrical connection or an excess of thermal buildup in the fixture as it operates over a long period of time can ignited those flammable substances, which can lead to a serious environmental hazards for workers.
Initially, and unlike metal halide or high pressure sodium fixtures, LED lighting does not rely on pressurized gases in a sealed glass bulb that can fracture. LEDs generate light by exciting electrons in a solid state environment. For durability, and to further enhance their explosion proof qualities, hazardous location LED lighting fixtures are contained in rugged frames and casings with tempered glass lenses that resist scratching, cracking, and fracture.
The LED fixtures themselves can pose a threat to hazardous work sites due to the heat generated by LED chips. The control circuitry that drives the LED fixture can get physically hot during operation, posing an ignition risk to the surrounding environment. Additionally, these heavy duty industrial LED fixtures utilize ultra-durable copper-free aluminum casings that protect the fixture’s internal components from the effects of being jarred or physically impacted during operation, thus further minimizing the potential for failure or explosion.
An explosion proof light might be sealed against the environment in which it is installed to separate spark-generating electrical components from any combustible materials, but an “explosion proof” designation does not mean that the fixture or its circuitry is completely sealed. In some cases, an explosion proof LED lighting fixture will be designed with a baffled pathway between its electrical components. This reduces or eliminates buildups in the concentrations of those substances around a potential ignition source.
To eliminate any confusion over whether a specific fixture is appropriate for a commercial or industrial environment that is deemed to be a hazardous location (i.e. a location in which flammable substances, such as chemical vapors, dusts, or fibers is present), explosion proof LED lighting will include Class, Division, and Group designations that can help a designer or facility manager match an LED fixture to a given application or location. These certified designations are more detailed and specific than the “E-Enclosed”, “S-Suitable” and “O-Open/Closed” standards that are commonly used for metal halide lighting. They break down hazardous environments to certify a given light for operation in certain conditions. Our explosion proof LED lighting fixtures are certified for a variety of hazardous location classifications.
The ultimate goal of explosion proof LED lighting is to increase the safety and security or workers and the integrity of a worksite in commercial and industrial facilities.