Most industrial lighting experts agree that designers and facilities managers should focus on three things when selecting explosion proof lighting that will be installed in a hazardous lighting location:
The lighting technology contained in the fixture
Whether the fixture is within the proper class, division, and group for the specific application
The cost savings and economic advantages that can be achieved with the chosen fixtures
Industrial Explosion Proof Lighting
The lighting technology that is contained in a fixture will likely be apparent from the fixture’s specifications. Most modern explosion proof lighting incorporates LED technology that generates high-quality lighting to improve safety and operations in every industrial facility. LED lighting is also up to 90% more efficient than other forms of industrial lighting, and modern LED industrial fixtures will operate for more than 50,000 hours, and in some cases more than 100,000 hours, before requiring replacement. Thus, an industrial facility can achieve the best cost savings with LED lighting.
The more critical decision when selecting explosion proof lighting inevitably comes when a designer or facilities manager needs to match a fixture’s hazardous lighting classifications with the actual environment in which the fixture will be installed. Like all hazardous location lighting, explosion proof lighting will be rated according to its suitability for particular classes, divisions, and groups of industrial hazards. Those classifications are based on the nature of the products within the environment, and whether those products are regularly or intermittently found in the facility’s atmosphere or are only stored or moved through a particular facility.
Hazardous Location Lighting Classifications
The National Electrical Code (NEC) and Canadian Electrical Code (CEC), as well as OSHA regulations and other workplace safety rules, classify hazardous lighting locations into one of three broad classes. Class I locations involve flammable chemical vapors, Class II locations feature flammable dusts, and Class III locations involve ignitable airborne fibers. A designer’s first step in selecting explosion proof lighting for a location is therefore understanding whether industrial operations at that location will involve vapors, dust, or fibers.
The second step is determining how and to what extent those flammable substances will be present in the atmosphere at a facility. That knowledge will generally dictate whether the explosion proof lighting in a particular Class should be further designated as Division 1 or 2. Division 1 explosion proof lights in all Classes are built to higher standards, and accordingly are more expensive than Division 2 products because flammable substances are more present in Division 1 hazardous lighting locations. The extra expense provides better separation between potential ignition sources and the flammable substances themselves.
The last step is assigning a proper Group designation to the facility. Group designations drill down to specific substances and the relative flammability of those substances. A designer or facilities manager who is tempted to select the highest Class, Division, and Group for a facility will inevitably spend more than if he or she had better matched the actual operations with the appropriate classifications for an explosion proof lighting fixture.