LED Explosion Proof Lighting

What Are Explosion Proof / Hazardous Location Lights?

Explosion proof and hazardous location lights are designed for areas where flammable gases, vapors, liquids, combustible dusts, ignitable fibers, or flyings may create a fire or explosion risk. These fixtures are used in classified industrial environments where ordinary electrical equipment may become an ignition source. The correct fixture depends on the hazardous location classification for the exact area where the light will be installed.

Before ordering, confirm the required Class, Division, Group, temperature rating or maximum surface temperature, certification, voltage, mounting method, ambient temperature rating, and environmental conditions. The area classification should be based on the materials present, release sources, ventilation, process conditions, housekeeping, and applicable site documentation or code requirements.

Class I locations involve flammable gases or vapors. In these environments, explosion proof fixtures are designed to contain an internal ignition if gas enters the enclosure and is ignited, then prevent that ignition from spreading to the surrounding atmosphere.

Class II locations involve combustible dusts, while Class III locations involve ignitable fibers or flyings. In these environments, the concern is different from Class I gas protection. Properly rated fixtures help reduce ignition risk by limiting dust, fiber, or flying entry and accumulation, controlling surface temperatures, and preventing arcs, sparks, or hot surfaces from igniting combustible material when properly rated, installed, and maintained.

Selection and Installation Note: Product specifications, hazardous-location markings, ratings, controls, certifications, and warranty coverage vary by model. Confirm the selected product specification before ordering. For code-sensitive, electrical, emergency, hazardous-location, or safety-critical applications, verify requirements with your local inspector, facility safety team, project specifier, or a licensed electrical professional.

Recommended Foot-Candles for Explosion Proof and Hazardous Location Lighting

Use the tool below for general starting foot-candle ranges by application. Foot-candle guidance helps estimate light levels for work tasks, inspection areas, process spaces, paint shops, distilleries, foundries, and classified industrial areas. It does not determine whether a fixture is suitable for a hazardous classified location. Fixture selection must still be verified against the marked hazardous-location rating, temperature code or maximum surface temperature, ambient rating, environmental exposure, and installation requirements.

Step 1: Find your foot candle levels

Step 2: Estimate your fixture count and space

When Explosion Proof Lights Are Required

Explosion proof or hazardous location lighting may be required where flammable gases, vapors, liquids, combustible dusts, ignitable fibers, or flyings are present and the area has been classified under applicable electrical codes. The fixture should not be selected only by brightness or fixture style. It must be suitable for the specific classified location.

How to Choose Explosion Proof Lights

The most important buying decision is not the wattage. The fixture must first match the hazardous location classification. That classification may be documented through a facility hazardous area assessment, area classification drawings, electrical design documents, or AHJ requirements.

Once the classification is confirmed, fixture style, lumen output, beam angle, mounting method, voltage, controls, corrosion resistance, temperature suitability, and foot-candle requirements can be selected.

Depending on the facility and jurisdiction, hazardous area classification may reference standards or guidance such as the NEC, NFPA 497, NFPA 499, NFPA 30, NFPA 33, API guidance, IEC 60079 standards, or other project-specific requirements. These references help determine whether gases, vapors, dusts, fibers, or flyings are present often enough to require classified electrical equipment.

Some projects use the NEC Class/Division system, while others may use a Zone system such as NEC Article 505 for gases and vapors, NEC Article 506 for combustible dusts, or international Zone 0, Zone 1, Zone 2, Zone 20, Zone 21, and Zone 22 classifications. Confirm which classification system applies before matching a fixture to the project.

Toyota Motor Manufacturing Indiana Upgrades to Explosion-Proof LED Lighting Case Study

The Backstory of Toyota Indiana's Relationship With LED Lighting Supply

The project began when Toyota Motor Manufacturing Indiana's (TMMI) Environmental Engineer, Lisa Harmon, reached out to LED Lighting Supply. Lisa needed support in upgrading the company’s Princeton, Indiana auto assembly plant paint booth lights. A contractor working on a separate project at the plant had previously installed our explosion proof fixtures. Their team wanted to order additional replacement fixtures for an area outside of the paint booth. As the project progressed, the purchasing process was handled through Toyota’s distributor, C & E Advanced Technologies. The purchasing channel transferred from Toyota directly to the distributor, while we continued our role as the lighting supplier for the project.

The Challenge of the Hazardous Location Project

The TMMI plant paints vehicle materials, builds automotive bodies, welds panels, and assembles entire vehicles. Heavy-duty work like this creates an environment where flammable vapors may be present during normal operations. Every light fixture in a hazardous area is subject to classification. The legacy fluorescent lighting serving those spaces had reached the end of its useful life and was producing uneven light levels across the work area. The lighting solution needed to raise illumination levels while meeting the safety requirements for high-level assembly work.

Lighting plan metrics:

• Product(s) Used: MLLG-E-LED-EXPLC-150-50-[V]-C1D1

Read the full case study

Blue Origin Explosion Proof LED Lighting Case Study

The Backstory of Our Collaboration With Blue Origin

LED Lighting Supply’s collaboration with Blue Origin started when Control Engineer Matthew Vanderploeg reached out in 2023. His team was seeking support on an explosion proof LED lighting upgrade for their rocket engine testing station in Huntsville, Alabama. Blue Origin is an aerospace company that develops and launches reusable rocket systems and space technologies. Their Alabama team was reconfiguring the historic Apollo-era Test Stand 4670 at NASA’s Marshall Space Flight Center near their production factory. The environment supported hot-fire certification and development testing of rocket engines, making it a hazardous location.

The 1000-watt metal halide system used in the old configuration produced uneven light levels. The inconsistent lighting caused operational concerns in the Class I, Division 2 (C1D2) rated environment. For an aerospace engineering operation, lighting is not a background concern. Engineers rely on recorded visual details to evaluate engine performance, and inconsistent illumination compromises the footage. Crews working around pressurized equipment need to see clearly at all times to ensure safety. The lighting upgrade had to improve overall visibility in the space while complying with hazardous location lighting requirements.

The Challenge of the Aerospace Explosion Proof Project

The following requirements shaped the project conversation right away. The light fixtures needed a C1D2 rating for the hazardous testing environment. The lighting solution needed to perform under high-speed camera recordings at 6,000 frames per second without flickering. LED fixtures can produce a flicker that the human eye does not see, but a high-speed camera captures it as brightness flashing across frames. With video footage meant to document engine behavior during the hot fire, that kind of detail contaminates the record.

The team had not yet determined how much light the cameras would require. The first order needed to function as a test run across multiple output levels rather than a final specification. The reconfiguration schedule was already underway, so Blue Origin required a lighting partner with readily available light fixtures rated for hazardous environments.

Blue Origin before with Metal Halide Lighting

Blue Origin after with LED Lighting

Lighting plan metrics:

• Product(s) Used: MLLG-E-LED-EXPLA-400-50-[V]-C1D2

Read the full case study

Barrette Outdoor Living’s Explosion Proof Lighting Case Study

The Backstory

Barrette Outdoor Living, an Oldcastle APG brand, struggled to properly illuminate an existing paint booth with inadequate, exposed fluorescent lighting, leading to a remodel. The Operations Manager, Brandon Hiller, sought LED Lighting Supply's Product Specialist, Joe Hawkins, for expert guidance on the LED lighting upgrade.

The Customer Challenge

The customer needed support in selecting the proper lighting solution for their demanding environment. Barrette Outdoor Living required fixtures for an area that frequently contains flammable paint chemicals and sprays such as lacquers and gelcoat. Additionally, the customer was renovating parts of the booth, including pulling down the ceiling, reframing the walls, and rewiring, while leaving the sprinkler system in place. Due to the intended use of the property, the flammable paint chemical exposure in the environment was not only a concern but also required specialized lighting specifications to comply with local standards. Our team understood that upgrading lighting in hazardous locations involves more complex planning than traditional spaces. The goal was to achieve brighter, safer lighting with minimal shadowing.

Lighting Plan We Created for the Customer

Lighting Plan Metrics:

• Mounting Height: 10 ft
• Fixture Used: 50 Watt Round Explosion Proof LED Light
• Average Foot Candles Achieved: 53
• Product(s) Used: MLLG-E-EXPLS2-150-50-C1D1

Read the full case study

Class, Division, and Group Classification

Hazardous-location lighting must be approved for the specific Class, Division, and Group assigned to the installation area. The Class identifies the general type of hazardous material, the Division indicates how likely the material is to be present in an ignitable concentration, and the Group identifies materials with similar ignition and explosion characteristics.

The examples below are common references, but they are not a substitute for the facility's documented area classification. Always confirm the exact gas, vapor, dust, fiber, or flying material present before selecting a fixture.

Class I Gas and Vapor Groups

Class I Groups A through D categorize flammable gases and vapors according to characteristics such as ignition energy, explosion pressure, and the ability of flame to travel through enclosure openings. A fixture must be marked for the specific group present or for a broader group combination that includes it.

Class II Combustible Dust Groups

Class II Groups E through G categorize combustible dust according to properties such as electrical conductivity, thermal characteristics, particle composition, and explosion severity. Dust that settles on a fixture may also interfere with heat dissipation, so the fixture's dust-group approval, enclosure rating, installation conditions, and maximum surface temperature should all be confirmed.

How to Read a Complete Hazardous-Location Classification

A classification such as Class I, Division 1, Groups C and D indicates that flammable gases or vapors may be present during normal operating conditions and that the fixture is approved only for the gas groups shown on its certification.

A fixture marked Class I, Division 2, Groups A, B, C, and D may cover more gas groups, but its Division 2 approval would not make it suitable for a Division 1 installation. Class, Division, and Group must be evaluated together. Approval for the correct Class alone is not sufficient, and a general description such as “explosion proof” does not establish suitability for every hazardous location.

Also verify the fixture's temperature code or marked maximum surface temperature, ambient temperature range, voltage, mounting orientation, environmental ratings, and any restrictions stated in the listing documentation. Conduit, seals, junction boxes, controls, emergency components, wiring methods, and other components may also need hazardous-location approval.

Hazardous-area classification and electrical equipment selection should be completed or verified by a qualified engineer, electrician, safety professional, or other person familiar with the facility's processes, material properties, applicable electrical code, and authority having jurisdiction.

T Rating and Maximum Surface Temperature

The T Rating, also called the temperature code or temperature class, identifies the maximum surface temperature the fixture is permitted to reach under the conditions covered by its listing. A fixture may have the correct Class, Division, and Group but still be unsuitable if its marked maximum surface temperature is too high for the hazardous material or accumulation conditions present.

Some hazardous-location fixtures are marked with broad temperature classes such as T3, T4, T5, or T6. Others may include lettered sub-codes such as T3A, T3B, T3C, or T4A. These lettered codes provide more specific maximum surface-temperature limits under the NEC Class/Division system.

Higher T-code numbers generally indicate lower maximum surface temperatures. Lettered sub-codes sit between the main T-code numbers. For example, T4A has a lower maximum surface temperature than T4 but a higher maximum surface temperature than T5.

Class I Gas and Vapor Temperature Selection

For Class I gases and vapors, compare the fixture's marked maximum surface temperature or temperature code with the ignition characteristics of the specific gas or vapor identified in the project classification. The fixture temperature marking must be suitable for that material and for the ambient-temperature range shown in the fixture listing.

Class II Combustible Dust Temperature Selection

For Class II combustible dust, do not select a fixture from a generic gas-style auto-ignition comparison alone. Dust hazards require consideration of the fixture's listed maximum surface temperature together with the ignition characteristics of the specific combustible dust and the conditions under which that dust may accumulate.

Important Class II factors include:

• Dust cloud ignition temperature: The minimum temperature at which a dispersed combustible dust cloud can ignite under the applicable test conditions.
• Dust layer ignition temperature: Accumulated dust on a hot surface can ignite at a different, and often lower, temperature than the same material dispersed as a cloud.
• Layer thickness: Thick dust deposits can retain heat and may require a lower allowable equipment surface temperature.
• Organic dust carbonization or dehydration: Organic materials may be damaged, dehydrated, or carbonized at temperatures below their cloud ignition temperature, and applicable electrical requirements may impose additional temperature limits.
• Dust accumulation on the fixture: Accumulation can reduce heat dissipation and raise equipment temperature.
• Dust composition and particle characteristics: Particle size, moisture, composition, and processing conditions can affect ignition behavior.
• Ambient temperature: The fixture's hazardous-location temperature marking is valid only within its listed ambient-temperature range.

The project engineer, EHS team, or other qualified professional should use the specific dust's documented test data, including applicable cloud and layer ignition characteristics, together with the electrical classification and fixture listing to determine acceptable equipment surface temperature.

Class III Fibers and Flyings Temperature Selection

For Class III ignitable fibers and flyings, temperature selection also should not be based solely on a generic material auto-ignition value. Fibers and flyings can accumulate on electrical equipment and may be heated, dehydrated, carbonized, or ignited by hot surfaces.

Applicable Class III requirements impose surface-temperature limits intended to reduce the risk of ignition or damaging accumulated fibers and flyings. The allowable temperature depends on the equipment and applicable code requirements, so confirm the fixture's marked temperature suitability rather than applying the Class I gas/vapor selection method directly.

Important: Temperature suitability is independent from Class, Division, Group, and environmental ratings. A fixture can have the correct Class and Division but still be unsuitable because of its maximum surface temperature, ambient-temperature range, dust accumulation conditions, or material-specific ignition characteristics.

Other Selection Factors

Important: This guide helps buyers understand hazardous location lighting terminology. It is not a substitute for a hazardous location assessment, area classification drawing, engineering review, or AHJ approval. Before purchasing or installing explosion proof lighting, confirm the fixture rating, installation method, temperature suitability, and site requirements with a qualified professional and applicable electrical code requirements.

Our customer replaced explosion proof fluorescent fixtures with our 100 Watt 4 Foot Explosion Proof Linear LED Light | 16000 Lumens linear fixtures to improve light quality and reduce maintenance compared with the previous fluorescent system.

Explosion Proof Lighting Compared with Other Industrial Fixtures

Explosion proof lighting is often confused with other industrial lighting categories. Some fixtures may look similar from the outside, but they are designed for different environments, safety requirements, and electrical classifications.

Certifications, Listings, and Compliance

Explosion proof and hazardous location lighting must be selected based on the specific classification of the area where the fixture will be installed. The required certification depends on the applicable code system, hazardous material, exposure likelihood, material group, temperature requirements, ambient temperature, installation environment, and AHJ or project requirements.

LED Lighting Supply offers selected explosion proof and hazardous location lighting fixtures with certifications and ratings for classified industrial environments. Always verify the fixture's listing, marked rating, maximum surface temperature or temperature code, ambient temperature range, voltage, mounting method, and environmental ratings before ordering or installing.

• UL 844 listed models available: UL 844 applies to luminaires for hazardous classified locations, including many Class/Division applications when the fixture is marked for the specific classification. Depending on the country, jurisdiction, and project, cUL, CSA, ETL, ATEX, IECEx, or other approvals may also be required.
• Class/Division ratings: North American hazardous locations commonly use Class I, II, or III; Division 1 or 2; and applicable Groups A-G depending on the gas, vapor, dust, fiber, or flying material present.
• Zone-based ratings: Some projects use Zone classifications, including Zone 0, Zone 1, and Zone 2 for gases and vapors or Zone 20, Zone 21, and Zone 22 for combustible dusts. Zone-based projects should be matched to the applicable NEC, IEC, ATEX, IECEx, regional code, and hazardous area requirements.
• ATEX and IECEx options available: For international or zone-based projects, selected fixtures may be available with ATEX or IECEx certifications. These systems use zone-based classifications and should be matched to the project's regional code and hazardous area requirements.
• T Rating / Maximum Surface Temperature: A fixture may have the correct Class and Division but still be unsuitable if its marked maximum surface temperature is too high for the hazardous material or accumulation conditions present. Class II and Class III applications require material-specific temperature review rather than applying only the Class I gas/vapor method.
• Environmental ratings: Confirm wet-location suitability, IP rating, corrosion resistance, impact resistance, vibration resistance, and ambient temperature limits where applicable.
• Installation system compatibility: Conduit, fittings, junction boxes, seals, switches, and other components must also be suitable for the classified area.

LED Explosion Proof Lighting FAQs

How Do I Choose Explosion Proof Lighting For A Classified Area?

Start by confirming the hazardous location classification for the exact installation area, then match the fixture to the required Class, Division, Group, T Rating, certification, voltage, mounting method, ambient temperature rating, and environmental conditions. After classification is confirmed, select fixture style, lumen output, beam angle, controls, corrosion resistance, and foot-candle requirements.

Does A Hazardous Location Fixture Need To Match More Than The Class Rating?

Yes, hazardous location fixtures must be approved for the specific Class, Division, and Group assigned to the installation area, and the T Rating must also be suitable for the material present. Approval for the correct Class alone is not sufficient, and a Division 2 approval does not make a fixture suitable for a Division 1 location.

Why Is The T Rating Important When Selecting Explosion Proof Lighting?

The T Rating identifies the maximum surface temperature a fixture is rated to reach under the conditions covered by its listing. A fixture may have the correct Class, Division, and Group but still be unsuitable if its surface temperature rating is too high for the hazardous material present.

Can Vapor Tight Fixtures Be Used In Hazardous Classified Locations?

Vapor tight fixtures are not automatically approved for hazardous classified locations. They resist moisture, dust, dirt, and contaminants, but classified areas require properly rated hazardous location lighting.

How Should I Plan Fixture Count And Light Levels?

Fixture count and lighting performance should be reviewed using mounting height, spacing, lumen output, beam angle, required foot-candle range, and uniformity. Foot-candle guidance can provide general starting ranges by application, but it does not determine whether a fixture is suitable for a hazardous classified location.

Which Explosion Proof Fixture Type Fits My Application?

The appropriate fixture type depends on the classified area, mounting height, work task, required light level, installation environment, and fixture listing. Round high bays are commonly used in open industrial areas and high ceilings, linear fixtures are used for lower ceilings and areas needing long, even light distribution, and flood lights are used for wide-area or directional hazardous location lighting.

What Should Be Verified Before Ordering Explosion Proof Lighting?

Verify the selected fixture's listing, marked hazardous-location rating, T Rating, ambient temperature range, voltage, mounting method, environmental ratings, controls compatibility, and warranty terms before ordering. Product specifications, hazardous-location markings, ratings, controls, certifications, and warranty coverage vary by model.

What Else Must Be Suitable For A Hazardous Location Lighting Installation?

The wiring method, conduit or cable system, junction boxes, sealing fittings, cable glands where permitted, boundary seals where required, switches, grounding, bonding, and other electrical components must be suitable for the classified area. Explosion proof lighting should only be installed by qualified electricians experienced with hazardous classified locations.