In recent years, boat owners have requested the installation of after-market or OEM-installed ornamental lights on their yachts to serve a variety of purposes including accent lighting on rub rails, underwater illumination, and other non-navigational purposes.

Many of these accents are blue in hue or emit a spectrum of colours that includes the colour blue. State law enforcement authorities in a number of states are now implementing laws that clearly prohibit the use of blue lights when a vehicle is in motion while driving.

A primary goal of these restrictions was to keep others from mistaking a recreational boat for one belonging to law enforcement or other rescue vessels. Law enforcement officials are particularly concerned that rub railings and underwater illumination could be misconstrued for flashing blue lights in severe sea conditions, which could result in arrests 

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Statewise Restrictions

While some states have accepted USCG illumination regulations that allow only the use of white, red, and green navigation lights while underway, several states have specific statutes restricting the use of blue navigation lights while on the water. 

Arizona RS 5-333(f) states: “No watercraft may display a blue light of any size or type unless it is either an authorized law enforcement watercraft of the federal, state or local government actually engaged in enforcement of this chapter or an emergency watercraft.”

Wisconsin also bans the use of blue accent lights while at anchor or underway: NR 5.17 (2) states: No vessel may be equipped with or display any blue colored light or lamp unless the vessel is a patrol boat.”

Don’t let your boat’s underwater lights confuse other boaters. The U.S. Coast Guard COLREGS (also known as the “Rules of the Road” for boaters) require that a boat avoid displaying any light that could be confused as another navigation light or another vessel.

A GUIDE TO MANDATORY REQUIREMENTS FOR BOAT LIGHTING

Even if you don’t spend much time out on the water after dark, boat lighting can make your vessel safer and more practical. In fact, in the majority of circumstances, boat navigation lights are needed by law.

Inside, outside, and underneath

Depending on the size of your boat, the type of boat lighting you instal will serve a variety of functions.

The exterior of the boat has surface-mounted deck lights that offer adequate illumination without interfering with your night vision, and flood lights or searchlights are essential for detecting any landmarks, buoys, or other objects that may have gone overboard.

Interior: portable torches or LED ceiling lights that operate on 12V can be used to illuminate the cabin or galley interiors. When travelling at high speeds, it is preferable to switch them off because they limit visibility.

Floating lights below the surface of the water, although not technically necessary, make a boat appear attractive at night and are useful if you’re slipping after dark.

LED boat lights are becoming increasingly popular since they last longer, consume significantly less electricity, and emit the least amount of CO2. Because LEDs are tiny, they can be used in a greater range of designs and fixtures.

Even though incandescent bulbs are being phased out, halogen lights are still available; nevertheless, they consume significantly more energy and have a shorter lifespan.

Requirements under the law

Navigation lights and their installation on recreational boats must comply with the International Regulations for the Prevention of Collisions at Sea, which are governed by international treaties (COLREGS).

In your local area, the Australian Maritime Safety Authority can give you with an overview of those rules as they pertain to you.

The fundamental rules are as follows:

The side lights are red on the port side and green on the starboard side, and they shine out across the sea in an arc pattern.

The stern lights are white and shine aft and forwards on either side, illuminating the area aft and forwards. (When the side lights and stern lights are combined, they form a complete circle of light.)

Those on the masthead are white and shine from 112.5° on the port side to 112.5° on the starboard side, illuminating the area from dead ahead to dead ahead.

Powerboats with a length of less than 20 metres must be equipped with side lights, a stern light, and a masthead light. Power containers that are shorter than 12 metres in length may only have a single all-around light.

Side lights and a stern light are required on sailing vessels less than 20 metres in length.

At night, all vessels except rowing or sailing boats less than 7m in length are required to display navigation lights, unless they are equipped with a white light from a torch or lantern, which must be displayed in sufficient time to avoid a collision.

White lights shine from every direction at all times.

Power and sail vessels less than 20 metres in length that are not anchored in a specific anchorage are required to display an all-around light.

The exception applies to vessels that are shorter than 7m in length unless they are located in a restricted waterway or anchorage, or in an area where other vessels normally navigate.

Whatever type of lighting you choose for your boat, you must ensure that it is properly and securely installed. A marine electrician should be consulted if you are in any doubt.

Following the completion of your boat, review our guidance to the lighting, wiring, and back visibility requirements for your boat trailer.

Night fishing with lights attracts zooplankton to the surface that are chasing the light source. The bait fish follow the zooplankton and then the game fish (which we’re chasing) follow the baitfish. Soon you have a lifecycle happening right before your very eyes.

Installing underwater lights on your boat, whether to lure fish or simply for show, will give it a glitzy appearance.

Face it, there is absolutely no reason to add underwater lights in your swimming pool. The fact is that they will not make your boat go faster or handle better.

However, they are quite attractive. I’ll admit that I was hesitant to instal underwater lights on my yacht because I considered them to be a frivolous waste of time and money. 

The enormous ships with the waterline all lit up that I’d seen at boat exhibitions didn’t appeal to me at first, but then someone gave me a couple as a present and I fell in love with them. After much deliberation, I decided to go ahead and instal them while my boat was being hauled for some routine maintenance.

Always follow the Regulations in your Stata/Country

Don’t let the underwater lights on your boat cause confusion for other boaters. A boat must avoid showing any light that could be mistaken for another navigation light or another vessel, according to the U.S. Coast Guard’s COLREGS (commonly known as the “Rules of the Road” for boaters). 

Keep in mind that flashing blue lights are only permitted on police vessels; nonetheless, when seen from a distance, wave action combined with the continuous rocking of high-intensity blue lights below the waterline can give the appearance of a police vessel.