Mailport January 2016 Issue

USCG Issues Alert on Uncertified Nav Lights

LED tri-color masthead lights
PS's February 2010 review of LED tri-color masthead lights featured USCG-certified lights and bulbs from Lopolight, OGM, Signal Mate, Dr. LED, LED Shop, Lunasea, and Aqua Signal.

The U.S. Coast Guard (USCG) recently released a safety alert regarding unapproved recreational and commercial vessel navigation lights, and they also issued a reminder that using some decorative lighting onboard (rope lighting, underwater lighting, etc.) may be a violation of the Nautical Rules of the Road.

Uncertified nav lights

According to the USCG, there’s a growing number of navigation lights on the market that do not meet technical certification requirements. These lights are typically less expensive, making them a tempting choice for uninformed shoppers. However, installing these lights (which likely do not have the proper chromaticity, luminous intensity, or cutoff angles) could land the boat owner in violation of Coast Guard regulations, and they could potentially cause an accident.

Specifications for lights vary depending upon the type of boat but regardless of the light source (i.e., incandescent or LED), they must follow the requirements prescribed in Rules 20, 21, 22 and Annex I of the “Rules of the Road,” which is the Convention on the International Regulations for Preventing Collisions at Sea (72 COLREGS) or the Inland Navigation Rules (33 CFR Subchapter E). Recreational vessel and uninspected commercial vessel navigation lights must meet American Boat & Yacht Council (ABYC) standard A-16, and commercial inspected vessels must have nav lights that meet Underwriters Laboratories standard UL 1104. You can find the Rules of the Road online at

Don’t get duped when shopping for navigation lights. Brush up on the Rules of the Road nav light requirements, and be sure that any light you buy clearly states the following information:

• USCG Approval 33 CFR 183.810

• Meets ABYC A-16 or equivalent

• Tested by an approved laboratory

• Name of the light manufacturer

• Number of Model

• Visibility of the light in nautical miles

• Date on which the light was type-tested

• Specification of bulb used in compliance test.

Also, be sure to check out our last review of LED tri-color nav lights (see PS February 2010 online) and previous articles that evaluated tri-color incandescent nav lights, masthead lights, sidelights, stern lights, and all-around white lights (see PS September 2005 and Jan. 15, 2002). All of the products we’ve tested meet the Rules of the Road regulations.

Decorative lighting hazards:

According the USCG safety alert, boat owners should be cautious about installing onboard decorative lighting underwater, on the rubrail, or just above the waterline, among other places. When installing such lights, be sure that they cannot be mistaken for navigation lights, do not impair the visibility or distinctive character of approved and properly placed nav lights, and that they do not interfere with the helmsman’s ability to keep a proper lookout. If any of these situations exist, you can be found in a violation of the Rules of the Road (Rule 20).

A violation can occur if the decorative lights can be construed as a nav light required by the Rules for another vessel. An example the USCG offered was when blue underwater LED lights appear to be flashing if there is any wave action; this may give the appearance of a flashing blue light, which is only authorized to be used by law enforcement boats. For questions or concerns, email

Comments (1)

Your recommendations are very informative. However, you left out one very critical requirement: "Make sure the navigation lights are certified for sailboats."

The vertical sector illumination angle requirements are greater for sailboats than for motorboats.* Why? Because sailboats heel. Motorboats only need: "at least 60 percent of the required minimum intensity is maintained from 7.5 degrees above to 7.5 degrees below the horizontal." Whereas: sailboats require: "at least 50 percent of the required minimum intensity is maintained from 25 degrees above to 25 degrees below the horizontal."

If the light isn't specifically labeled as being approved for use on sailboats, then you can be nearly certain it does not meet that requirement for sailboats - because it's cheaper to concentrate the light into a narrower vertical beam to get the required luminosity.

I tested LED navigation lights from three manufactures that did not comply with the more stringent sailboat vertical sector requirements. I set the lights up on a vertical board, illuminated a wall at a measured distance, and then measured the points where the light was cut off above and below the vertical center line. Applying a little trigonometry gave me the angles. All three had sharp cutoffs less than +/- 12 degrees, and none were labeled as being appropriate only for motorboats. If my boat heeled past 12 degrees (which she often does), both my port and starboard navigation lights as seen by other vessels would vanish! I'm not interested in my navigation lights being visible only to satellites and submarines!

It is also a good idea to make sure the lights carry the European "CE" seal to give you some assurance they won't wipe out your radios from RF interference (RFI). U.S. manufacturers can "self certify", but to get the CE seal, the manufacturer had to pass a lab test to certify the light had low RFI.

* Annex I, INTERNATIONAL: Section 10; INLAND: S 84.19 Vertical sectors

Posted by: S/V Ad Astra | January 21, 2016 12:53 PM    Report this comment

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