| Indoor process area with flammable gas or vapor | Confirm the hazardous-area classification, gas group, temperature class, and applicable local electrical code. In systems using zones, establish the zone from the site’s hazardous-area assessment. | Choose a luminaire specifically certified for the site’s classified area and installed position. A sealed or weather-resistant enclosure alone does not establish explosion protection. | Use a certified emergency model or approved emergency-lighting arrangement. Select the required duration from the applicable code and evacuation plan; 90 minutes is a common requirement in some jurisdictions, but is not universal. | Check certification markings, permitted ambient temperature, mounting method, cable entries, and whether the emergency function is included in the certification. |
| Dusty industrial space, such as grain, food, or powder handling | Determine whether combustible dust is present and identify the applicable dust zone or Class/Division, as well as the dust group and maximum surface-temperature limits. | Select equipment approved for the relevant combustible-dust classification. Consider an enclosure and optics that can be cleaned without compromising seals or certification. | Match battery duration to the required evacuation period and expected response time. Confirm that dust ingress protection and battery performance are suitable for the operating environment. | Verify dust-specific approval, permitted surface temperature, enclosure condition, cleaning procedure, and access for inspection and testing. |
| Outdoor tank farm, loading bay, or exposed processing area | Use the site’s area-classification drawings to identify hazardous boundaries and any gas or dust risks at the mounting location. Account for wind, rain, salt, and temperature extremes. | Choose a certified hazardous-area light with environmental protection suitable for the exposure. Specify corrosion-resistant materials where the site atmosphere requires them. | Consider self-contained battery backup or a suitably engineered central emergency supply. Check low- and high-temperature effects on battery capacity and charging. | Review ingress protection, corrosion resistance, impact exposure, mounting height, beam coverage, and safe access for maintenance. |
| Escape route, stairway, or exit near a classified area | Confirm whether the exact mounting point is inside the hazardous boundary. Do not assume that a nearby non-hazardous corridor has the same classification as the process area. | Use certified equipment wherever the installed location is classified. Position the light to illuminate the route, changes in level, exit signs, and critical safety equipment as required by the lighting plan. | Provide the legally required emergency duration and maintain the system in accordance with local testing rules. A longer duration may be appropriate where evacuation or emergency response is expected to take more time. | Check maintained or non-maintained operation, automatic changeover, test access, illumination coverage, and compatibility with the site’s emergency-lighting system. |
| Remote or difficult-to-access hazardous location | Confirm classification and environmental conditions, then assess how often the light and its battery can be safely inspected or replaced. | Prefer a certified, serviceable design with clearly documented battery replacement and inspection procedures. Avoid choosing solely on initial purchase cost. | Compare battery type, rated duration, recharge time, expected service life, and performance at the site’s ambient temperature. Consider a monitored system if faults could otherwise go unnoticed. | Check spare-part availability, maintenance intervals, self-test or remote-monitoring features, and whether servicing can be performed without violating certification. |
| Mixed gas-and-dust risk or uncertain classification | Obtain a competent hazardous-area assessment before specifying equipment. Gas and dust classifications, groups, and temperature limits are not interchangeable. | Use only a product whose certification and installation conditions cover every relevant hazard at the location. Resolve any uncertainty with the responsible electrical or process-safety specialist. | Set emergency runtime from the applicable code, evacuation strategy, and risk assessment rather than assuming one duration fits every site. | Check the complete marking and certificate, including gas and dust suitability where relevant, ambient limits, installation restrictions, and emergency-mode approval. |