On a marine vessel, an explosion-proof light must match the hazardous area where it will operate. ATEX certification is used for equipment intended for hazardous areas under European requirements, while IECEx provides an international certification scheme. They are related, but not interchangeable. Check the certificate and the exact light model, not just a product family name. Small print matters.

In the United States, NEC Class I identifies locations where flammable gases or vapors may be present. The applicable division or zone, gas group, and installation rules still need to match the site. T-codes show a light’s maximum surface temperature: for example, T6 means no more than 85°C under specified conditions. That matters near heat-sensitive vapors. A lower temperature rating is not automatically suitable; the hazard assessment must guide selection.

Salt spray, vibration, and cramped mounting spaces add practical checks. Confirm ingress protection, corrosion resistance, cable entries, and operating temperature alongside the hazardous-area markings. Certifications do not guarantee every marine performance requirement. A label can feel reassuring, but I would still verify the certificate scope and installation conditions with a qualified electrical professional. Details get missed at sea.

For marine explosion-proof lights, lumens describe total light output, not how bright a deck will feel. A 5,000-lumen fixture may illuminate a narrow work area intensely yet leave nearby steps dim. Mounting height, lens condition, and reflective surfaces all affect the result. Check illuminance at the actual task area when possible. Numbers alone can mislead.

Efficacy, measured in lumens per watt, helps compare how efficiently fixtures turn electrical power into light. It does not guarantee better visibility or longer service life. Beam angle matters too: a narrow beam can reach a distant mast or loading point, while a wider beam spreads light across a walkway. Too wide, and useful brightness may fade. Too narrow, and shadows can hide edges. I would compare beam diagrams at the intended mounting distance, then inspect the fixture’s marine corrosion, vibration, and hazardous-area ratings. One detail is easy to miss: salt residue on a lens can quietly reduce output. Specs deserve a second look.

For marine explosion-proof lights, IP66 and IP67 describe protection against dust and water—not resistance to explosive atmospheres. IP66 enclosures are dust-tight and tested against powerful water jets. That suits exposed decks, washdown areas, and spray near working vessels. But IP66 does not certify a light for immersion. Water still finds gaps.

IP67 adds protection during temporary immersion, typically up to one metre for 30 minutes under IEC 60529 test conditions. The rating is useful near bilges or low mounting points, where water may collect. It does not automatically mean the fixture also passed the IP66 water-jet test; check for both ratings when both hazards matter. Salt corrosion is another issue entirely. An IP code says little about the quality of metal, coating, fasteners, or cable-gland seals. I would not treat either number as a complete durability promise. Inspect gaskets for flattening, check for rust around screws, and confirm cable entries remain tight after installation. Even a highly rated enclosure can fail when seals age or maintenance slips. Small details matter. Also verify the light’s separate hazardous-area certification for the intended location; IP ratings alone do not establish explosion protection.

A useful comparison of ten marine explosion-proof lights starts with delivered output, not the largest number on a product sheet. Compare rated lumens, beam angle, efficacy, and light distribution at the working distance. A 6,000-lumen floodlight may illuminate a deck well but create glare in a narrow machinery space. Check independent photometric test data where available. Numbers need context.