Boat Navigation Lights: What You Need To Know

Boat navigation lights are an essential safety system, designed to prevent collisions and communicate information about a vessel's size, activity, and direction of travel. The type of nav lights required on a boat depends on factors such as the length of the boat, whether it is powered by an engine, and the location and weather conditions. In the US, the specific requirements for boat navigation lights are outlined in the US Coast Guard's Navigation Rules and Regulations Handbook, while in Canada, similar guidelines are provided in Transport Canada's Safe Boating Guide. These lights are crucial for safe boating, especially when operating at night or in conditions of reduced visibility.

Red and green sidelights

The use of these coloured lights is crucial for collision prevention, especially at night or during periods of reduced visibility, such as in foggy or cloudy conditions. By displaying the appropriate navigation lights, boats can see each other and take the necessary actions to avoid collisions. The sidelights shine from dead ahead to 112.5° aft on either side of the vessel, ensuring visibility from a distance.

It is the responsibility of the boat owner or operator to ensure that the correct navigation lights are displayed and that they meet the legal requirements for colour, intensity, location, and visibility. These lights must be displayed from sunset to sunrise and during restricted visibility conditions. Failure to do so can lead to safety hazards and legal consequences.

In addition to the red and green sidelights, boats typically have white stern lights and masthead lights. The stern light is visible only from the rear or nearly behind the vessel, while the masthead light shines forward and to both sides. Together, these lights provide essential information about the boat's size, activity, and direction of travel, helping nearby vessels take appropriate actions to avoid collisions.

Stern lights

Purpose and Function

Visibility Requirements

The visibility range of stern lights is determined by the size of your boat. For boats less than 12 meters (39.4 feet) in length, the stern light must be visible from at least 2 nautical miles away. On the other hand, boats between 12 and 20 meters (39.4 to 65.6 feet) require a stern light visible from a minimum of 2 nautical miles.

Angle of Illumination

Types of Stern Lights

• LED Stern Lights: LED lights are energy-efficient and provide bright illumination. They are available in different sizes and voltages, ensuring compatibility with a range of boat types.
• Telescoping Stern Lights: These lights are adjustable in height and can be stowed away when not in use. They are often designed to meet USCG (United States Coast Guard) requirements.
• Fold-Down Stern Lights: Fold-down stern lights are compact and can be folded down when not in use, making them suitable for boats with limited space.
• All-Round Stern Lights: These lights provide 360-degree illumination, ensuring visibility from all directions. They are often used in conjunction with sidelights to meet navigation light requirements.

Purchasing Stern Lights

In conclusion, stern lights are a critical safety feature for any boat operating during nighttime or reduced visibility conditions. By understanding the requirements and options available, you can make an informed decision when equipping your vessel with the appropriate stern lighting.

Masthead lights

The visibility range of masthead lights depends on the size of the boat. For boats greater than 39.4 feet (12 meters) but less than 65.6 feet (20 meters), the masthead lights should be visible from at least two nautical miles away. On the other hand, vessels that are 20 meters to 50 meters in length must have masthead lights visible from a minimum of three nautical miles, and boats over 50 meters require a minimum visibility of five nautical miles.

It is important to note that masthead lights are not exclusive to sailboats. While they are commonly associated with sailboats, they are also used on powerboats. According to the International Regulations for Prevention of Collisions at Sea (IRPCS), power-driven vessels that are longer than 50 meters may use two masthead lights.

In terms of installation, it is worth mentioning that the height of the masthead light depends on the size of the boat. For boats greater than 39.4 feet, the masthead light should be positioned at least 8 feet above the gunnel. Additionally, while the light should be placed over the fore and aft centerline of the vessel, it does not necessarily need to be at the very top of the mast.

Powerboat lights

Powerboats are required to display navigation lights between sunset and sunrise, as well as during periods of restricted visibility, such as in fog or rain. This is to prevent collisions and allow nearby vessels to be seen. Powerboats include sailboats operating under engine power.

The navigation lights required depend on the size of the boat. Powerboats less than 12 metres (39.4 feet) in length require one all-round white light and sidelights. The all-round white light needs to be visible from 360 degrees and from two miles away, while the sidelights—one red on the port side and one green on the starboard side—need to be visible from 112.5 degrees and from one mile away. For boats of this size, the all-around white light needs to be positioned at a height of at least 39 inches above the sidelights.

Powerboats that are between 12 and 20 metres (39.4 to 65.7 feet) in length require one masthead light, one stern light, and one pair of red and green sidelights. The masthead light, a white light at the front of the boat, needs to be visible across 225 degrees and from two miles away. The stern light, another white light at the rear of the boat, needs to be visible across 135 degrees and from two miles away. The red and green sidelights need to be visible across 112.5 degrees and from a distance of one mile. For boats of this size, the masthead light must be positioned at a height of at least 8 feet above the gunnel.

Powerboats that are over 20 metres (65.7 feet) and less than 50 metres (164 feet) in length require one masthead light, one stern light, and red and green sidelights. The masthead light must be visible for 5 nautical miles, while all other lights must be visible for 2 nautical miles.

Sailboat lights

The lighting requirements for sailboats vary depending on the size of the vessel and whether it is under sail or power. Sailboats under 7 metres in length should, if practical, exhibit regular navigation lights. If this is not possible, they must have ready an electric torch or lantern showing a white light, which should be exhibited in sufficient time to prevent a collision.

Sailboats under sail that are 7-20 metres in length have several options for displaying navigation lights. They can display a green light on the starboard side and a red light on the port side, along with a white light at the stern. Alternatively, they can display a tricolour light at the top of the mast, which includes a red light to port, a green light to starboard, and a white light aft, all in a single light creating a full circle. This option can only be used when under sail. A third option is to display a green light off the starboard bow, a red light off the port bow, and a white light off the stern, with the additional option of displaying red and green all-round lights at the top of the mast, with the upper light red and the lower light green. This third option is rarely used today but is still accepted.

When a sailboat is under power, it is considered a powerboat and must follow the same rules as a powerboat. This means displaying a masthead light forward, sidelights, and a stern light. The masthead light must be above the sidelights. The sidelights are coloured red on the port side and green on the starboard side, shining in an unbroken arc of 112.5 degrees from dead ahead to 22.5 degrees abaft the beam on each side. The stern light is white, shining in an unbroken arc of 135 degrees, centred on dead astern. Powerboats less than 12 metres in length may substitute an all-around white light and sidelights.

Frequently asked questions