Marine LED Light Buying Guide
Salt water destroys ordinary lighting. A marine light must survive corrosion, constant moisture, UV exposure and vibration — while meeting navigation regulations. This guide explains how to specify lights that last seasons, not months.
Quick-Reference Specs
| Parameter | What to look for |
|---|---|
| Corrosion | Salt spray tested ≥480 h (ASTM B117 / GB/T 10485) |
| Water rating | IP66 deck lights / IP68 underwater & transom lights |
| Voltage | 12V / 24V DC boat systems, with reverse-polarity protection |
| UV resistance | 1000 h UV aging (GB/T 16422.3) for lens & housing |
| Housing | 316 stainless steel or marine-grade aluminum + sealing |
| Nav lights | Must meet COLREG / USCG / RYA visibility arcs |
| Legal colors | Red/green sidelights, white stern/masthead, white anchor light |
Corrosion testing is the dividing line
Ask every supplier for a salt-spray test duration. Unnamed "marine-rated" lights commonly fail within one season at the coast. 480 hours of neutral salt spray on structural parts — and 720 hours on fasteners — is the benchmark Aurora tests to.
Physically inspect: 316 stainless hardware (not plated steel), gasketed lens joints, and potting around the cable gland.
Water rating by mounting position
Deck & spreader lights: IP66 is sufficient — they take spray, not submersion.
Transom, hull-side and underwater lights: IP68 with pressure-rated depth. Check the cable entry is a gland, not a hole with silicone.
Lights that ride below the waterline face hydrostatic pressure plus growth — choose housings rated for continuous immersion.
Navigation lights: regulation is not optional
Sidelights, stern light, masthead and anchor lights must meet visibility arc and range requirements (COLREGs; USCG for US waters). "Decorative" LEDs do not qualify.
Verify the light is certified for its position (port red / starboard green / stern white) and visible at the required range for your vessel length.
Electrical system realities on boats
Boat voltage is noisy: engine cranking, windlass loads, charger ripple. Choose lights with 9–36V regulation and transient protection.
Bond all light housings to the boat's grounding/anode system where applicable, to prevent galvanic corrosion attacking the housings.
UV and heat: the silent killers
Tropical UV degrades polycarbonate lenses into yellow haze. Look for UV-aged tested lenses (1000 h UVA-340) — Aurora publishes these reports — or glass lenses for fixed installations.
Underwater lights generate heat out of water: never run them during haul-out or dry testing beyond a few seconds.
Frequently Asked Questions
Can I use automotive LED lights on my boat?
Only if they are IP68 and salt-spray tested. Automotive lights resist rain, not immersion or salt chemistry — expect housing and fastener corrosion within months.
What color underwater light is best?
Blue travels through coastal water best and looks brightest; green also performs well. White looks clean but attracts more growth. Choose trim housings that let you change LEDs if you want flexibility.
Do underwater lights need through-hull fittings?
Premium designs mount flush through the hull with a sealed through-hull — these must be installed professionally. Surface-mount transom lights are the easier retrofit for outboard boats.
How do I stop algae growing on underwater lights?
You cannot fully prevent it; choose housings with replaceable lenses and clean them at each haul-out. Running the lights periodically also slows growth.
Need help specifying your lighting?
Our engineers answer technical questions within 24 hours. OEM/ODM projects start from 100 pcs with IATF 16949 certified processes.