From Volume 2 Issue 3 of Connected.
Selecting lighting for a facility with a hazardous environment can be complicated. Hazardous settings need lighting and control solutions that provide high visibility, uniform light and visual comfort with no shadows or glare to ensure worker safety and support a productive work environment. Appropriate lighting solutions for these demanding environments must withstand factors like ambient temperatures, humidity, solvents, corrosives and other conditions in order to meet hazardous classifications and ratings.
For facilities like an ethanol plant, the task is challenging because of the product being produced. Ethanol is a clear, colorless and highly flammable liquid that has multiple uses. Used as a renewable fuel, the Department of Energy reports that 98 percent of U.S. gasoline contains ethanol to oxygenate the fuel, reducing air pollution and increasing vehicle performance. It is used in alcoholic beverages, in personal care products as an astringent, as a preservative or bacteria-fighting agent or in household products as a solvent. It is also used as a food additive to help evenly distribute food coloring and enhance food extract flavors.
Due to the multifaceted processes within an ethanol plant, combustible gases, vapors or liquid may be present in some areas while combustible grain dust may be present in others. Determining the correct hazardous LED lighting needed is essential for a safe working environment. The first step in this task is determining if and which hazardous classifications and ratings must be met in each specific area.
In the U.S., guidelines and electrical codes provided by the National Electrical Code (NEC) and UL 844 help determine the correct classification of hazardous areas and the proper equipment to use under those conditions. Andy Kraft, Regional Industrial Director for Holophane, Acuity Brands, says that understanding the Class and Division classifications is critical to accurately choose the best LED lighting solutions for various environments within an ethanol plant. According to UL 844, Class defines the nature of the hazardous material in the environment. Division defines the probability of hazardous material being able to produce explosive or ignitable mixture based upon its presence. Ratings can be further guided by Group, which defines the type of hazardous material present.
Along with hazardous classifications, T-Codes, established by the NEC, indicate the operating temperature or temperature range during the luminaire's use. If the T-code for your selected luminaire at the relevant ambient temperature is lower than the designated ignition temperature of the explosive hazard (gas, vapor, liquid or dust) encountered, then the fixture is thermally suitable for that classified area.
CLASS 1/DIVISION 1
Lighting classified as Class 1/Division 1 meets the most stringent hazardous requirements. Areas of the ethanol plant that would require this rating are the distillation areas and fuel storage areas, where both finished ethanol and gasoline (used as a denaturant to make the ethanol undrinkable) are stored.
Holophane's Hazardous C1D1 line of luminaires, released in March of 2023, was designed to meet the challenges of Class 1/Division 1 classification. This line of explosion-proof LED luminaires is dual-rated for Class 1/Division 1 and Class 1/ Division 2, as well as IP66 and NEMA 3 and 4 ratings. With outstanding thermal shock and impact-resistant construction, the line provides a wide range of lumen packages and light distributions with multiple mounting options for versatility.
The C1D1 line includes the HEXF1 and HEXF used for low bay and floodlighting applications. The HEXS hazardous linear fixture, also rated for wet locations, is available in two-foot and four-foot lengths. The HEXSEM, another hazardous linear fixture, includes emergency battery backup to enhance safety during power outages. The HET hazardous tubular linear fixture is designed for precise optical control for flexibility, operates in a wide range of ambient temperatures and includes emergency backup.
CLASS 1/DIVISION 2 AND CLASS 2/DIVISION 2
Class 1 or Class 2 classifications coupled with Division 2 ratings are areas where hazardous materials are less likely to combust under normal circumstances. Areas of the ethanol plant garnering Class 1/Division 2 or Class 2/Division 2 ratings would generally involve grain handling. These would include areas where grain is loaded into or off rail cars or trucks, conveyance areas and other grain-handling areas.
The longstanding Petrolux® line from Holophane offers hazardous location options ideal for Class 1/Division 2 or Class 2/Division 2 rated areas. The PXLH LED round low bay for hazardous locations is a versatile single LED replacement for up to 250W HID. Beyond class and division ratings, it has multiple ratings like IP65, IP66, IP67, NEMA 4X and NSF (for food grade requirements). The PXHH LED round high bay has similar ratings but is only classified for Class 1/Division 2.
Both luminaires feature prismatic borosilicate glass which directs light to specific areas and reduces harsh glare. Both also offer the option for the patent-pending, non-rigid silicone lens. Virtually indestructible, this lens won't brown or discolor and does not attract dirt and dust. The EMXH is a hazardous linear low bay fixture with high durability, high performance and a water-resistant seal.
According to Dave Hargather, Vice President of Industrial Vertical at Holophane, Acuity Brands, most Holophane hazardous lighting is available with control options. The nLight® AIR is a wireless lighting control solution bringing networked lighting controls that are simple to specify, install and use. nLight® AIR easily scales from a simple solution connecting a few control devices to a fully networked, campus wide solution. Used for indoor or outdoor applications, this solution works for both new construction and retrofits. Kraft mentions one exception — Holophane's Hazardous C1D1 products cannot use controls due to their intrinsically safe nature. They must be fully sealed to prevent release of any spark or gas that might combust due to its environment.
It might seem the best course is to choose Class 1/Division 1 classified lighting that is nearly always dual-rated and would cover all hazardous classifications, but Kraft says that is not cost-effective when considering your Total Cost of Ownership (TCO) or life cycle costs. “At an ethanol facility, there are going to be multiple ratings and multiple areas. Some areas may not require a hazardous rating.” For example, large outdoor areas of the plant such as parking lots, rail loading areas or roadways leading to and from the plant may not need a hazardous rating.
LIGHTING RATED FOR OTHER CORROSIVE OR ENVIRONMENTAL FACTORS
In these non-hazardous areas, luminaires may carry other environmental ratings such as IP, NEMA, vibration or corrosion ratings that are necessary to perform well in the harsh ethanol plant environment. Products like Holophane's HMLED4 high mast area lighting, Predator floodlights and American Electric Lighting's Autobahn roadway luminaires are equally important for the safety and security of the ethanol site's perimeter. High mast lighting typically provides light along roadways from fixtures placed on 60- to 80-foot poles or provides outdoor area lighting using the least number of poles, says Hargather. Each outdoor solution often uses controls to reduce energy usage and lighting costs, plus lengthen fixture life.
If your next lighting project requires hazardous lighting, let Kirby Risk help you select the appropriate lighting to meet hazardous classifications and other environmental ratings. Partnering with manufacturers like Holophane, Kirby Risk can provide lighting audits, facility upgrade estimates, design and specification, complete ROI or TCO calculations and help you capture incentives from local utilities to help reduce costs. We can help you uncomplicate the process to safely and effectively light up your hazardous location!