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Some Enlightenment on Vessel Lighting

01.01.13 | INSIGHTS

By Marilyn Raia
Shareholder, San Francisco Office, 415.352.2721

Lights on an automobile give information to the driver about what is on the road ahead. Lights on a vessel give no information to the vessel operator. Rather, lights on a vessel give information to others about the vessel’s course and characteristics so that collisions can be avoided. Federal law dictates what lights are required on a vessel. The lighting laws are not as simple as one might expect, and are said to “embody an elaborate code”. This article addresses some vessel lighting basics.

Finding the Lighting Rules

Vessel lighting requirements in the United States date back to the mid 19th century. The current versions of the requirements are found primarily in two places: the International Regulations for Preventing Collisions at Sea 1972 (known as the “Colregs” or “International Rules”) and the Inland Navigational Rules Act of 1980 (known as the “Inland Rules”). The former is an international treaty adopted in 1972 and entered into force in 1977. The latter is a federal statute enacted by Congress in 1980.

The International Rules and the Inland Rules contain many types of navigation-related rules in addition to vessel lighting rules. The International and Inland rules are similar, but not identical. Both are available on the Internet for no charge or side-by-side in a booklet published by the Coast Guard.

The Basic Application of the Vessel Lighting Rules

The vessel lighting rules apply to all “vessels,” and “vessels” is defined broadly as watercraft including non displacement craft and seaplanes, used or capable of being used for transportation on the water. That means the vessel lighting rules apply to a wide variety of watercraft including, but certainly not limited to, canoes, sailboats, fishing vessels, tugs, seaplanes, barges, containerships, and tankers as well as partially submerged vessels, anchored vessels, and vessels being towed.

Whether the International Rules or the Inland Rules apply depends on where the vessel is. The International Rules apply to vessels on the high seas and on all waters connected to the high seas that are navigable by seagoing vessels. The Inland Rules apply to vessels on the inland waters of the United States and to United States vessels in the Canadian waters of the Great Lakes, if not in conflict with Canadian law. Federal regulations provide a line of demarcation for the applicability of the International and Inland Rules. That line generally follows the coastline. For example, the International Rules apply in San Francisco Bay.

The lighting rules apply from sunset to sunrise. During that time, no other vessel lights are permitted to be displayed that could be mistaken for the required lights, or that could interfere with the visibility or distinctive characteristics of the required lights. Lights that impair a vessel’s ability to keep a proper lookout are also not permitted. The lighting rules are not suspended during inclement weather.

Types of Lights

The International Rules provide for six different types of lights. They are a masthead light, sidelights, a stern light, a towing light, an all-around light, and a flashing light. The Inland Rules provide for the same six types of lights plus a seventh, a “special flashing light”. Both sets of rules provide for four different colors of lights: white, red, green and yellow.

Each of the required types of lights has characteristics that may include color, intensity, and location on the vessel. For example, under the International Rules, a masthead light is “a white light placed over the fore and aft centerline of the vessel showing an unbroken light over an arc of the horizon of 225 degrees and fixed that it shows light from right ahead to 22.5 degrees abaft the beam on either side of the vessel.” Under the Inland Rules, the definition of a masthead light is the same, except on vessels less than 12 meters in length, the masthead light need only be placed “as nearly as practicable” to the fore and aft centerline of the vessel.

How intense the required lights must be is dependent on the size of the vessel. For example, under both sets of rules, the masthead light on a vessel more than 50 meters in length must be visible for a minimum of six miles. On vessels more than 20 but less than 50 meters in length, the masthead light must be visible for a minimum of five miles. On vessels from 12 to 20 meters in length, the masthead light must be visible for a minimum of three miles. On vessels less than 12 meters in length, the masthead light must be visible for a minimum of two miles.


A vessel’s type, type of propulsion, and activities also affect what lights are required. There are basic lighting rules for a power-driven vessel when underway, and modifications of the basic lighting rules if a power-driven vessel is engaged in certain activities such as towing or being towed, dredging, trawling, fishing but not trawling, mine-clearing or diving. There are also lighting requirements for vessels under sail, vessels under sail but also propelled by machinery, and vessels under oars. Vessels restricted in their ability to maneuver and vessels at anchor are also required to display particular lights.

Consequences of Not Following the Lighting Rules

When followed, the lighting rules provide important information about a vessel. When the lighting rules are not followed, serious consequences may follow. Indeed, the failure to properly light a vessel has been said to be “one of the most recklessly unlawful acts a vessel can commit”. And, under The Pennsylvania Rule, when a vessel in a collision is found to have violated a statutory rule designed to prevent collisions, such as the lighting rules, a presumption of fault is raised. To avoid liability, the violator must prove the violation did not and could not have played a role in the collision. It is a very difficult burden.

The First National Bank of Chicago v. Material Service Corporation, 597 F.2d 1110 (7th Cir. 1979) is one of many cases addressing the consequences of improper vessel lighting. That case involved a nighttime collision between a 16-foot pleasure craft and a flotilla of barges being pushed by a tug. The barges had red and green lights on their bow corners and a flashing amber light at the center head. A forward facing white light on the tug’s pilothouse was not illuminated although there were red and green directional lights on the pilothouse roof. The tug operator saw the pleasure craft’s red light and perceived the vessels to be on a collision course. He reversed the tug’s engines and steered right, believing he was leaving a wide expanse of clear water for the pleasure craft. The pleasure craft struck the center of the bow of one of the barges and two occupants of the pleasure craft were killed. The district court found the pleasure craft solely at fault. The Seventh Circuit reversed the decision and sent the case back to the district court. On retrial, the district court found the tug and barge to be in violation of three lighting rules as well as other navigational rules. It allocated sole fault in the collision to the tug and barge. The Seventh Circuit affirmed the finding of fault imposed on the tug and barge due to improper lighting and held the lighting configuration created a “traveling trap” moving down a dark river. But, the Seventh Circuit also held some fault should be attributed to the pleasure boat operator. It reasoned the pleasure boat operator should have been able to see the lights on the barges and been on warning that something, albeit unidentifiable at the time, was ahead.

The lighting rules may not be disregarded in favor of a local custom. Kaseroff v. Etersen, 136 F.2d 184 (9th Cir. 1943) involved a nighttime collision between two fishing vessels, the Martindale and the Yankee Clipper, off the California coast. The night was moonless but clear, and the sea was calm. The Martindale located and circled a school of fish. While preparing to make a set, the Martindale was struck by the Yankee Clipper and suffered hull damage. At the time of the collision, neither vessel had a white masthead light. Instead, under a local custom, they each had a red masthead light which, when illuminated, showed the vessel had priority over a school of fish. The district court found the Martindale had complied with all laws and customs, and was not at fault in the collision. The Ninth Circuit disagreed. It held a local custom of not displaying a white masthead light did not excuse compliance with the International Rules nor relieve the offender of the consequences of non-compliance. It held both vessels equally at fault for improper lighting and reduced by half the damages previously awarded to the Martindale’s owner.

The lighting requirements in the International and Inland Rules are designed to convey information about a vessel’s size, activities, and course so that collisions can be avoided. Mariners should determine what lighting requirements apply to their vessels and make sure their vessels are in strict compliance to avoid significant financial consequences.

This article is being republished or posted with permission extended by Pacific Maritime Magazine

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