Steaming Light


Definition of Steaming Light

A steaming light is the white, forward-pointing light that a motorized watercraft carries at night or when there is poor visibility.

It’s also known as a masthead light or mast light.

diagram showing navigation light placement

According to COLREGs, the collision regulations, a power driven vessel that is underway, must have a steaming light visible from directly ahead to 22.5 degrees behind the beam on either side.

In addition, a boat under 50 meters long may have one steaming light, but larger boats must show a second, similar light set farther back and higher up on the boat to increase visibility.

It’s important to pick a light visible for 2–3 nautical miles. The LED Masthead Lamp is a long lasting, energy efficient light that is compliant with this rule thanks to its 3 NM and 5 NM options.

A sailboat doesn't have a steaming light but may display a tricolor light at or near the top of the mast.

The LED Tri-Color with Anchor Lamp lights green (starboard), red (port) forward, and white towards the stern.

LED Tri-Color with Anchor Lamp from Apex Lighting

Example of Steaming Light in a Sentence

"The steaming light on the front masthead of the boat provided clear visibility of its direction of travel to nearby vessels."

Synonyms: mast light, masthead light

Related Terms for Steaming Light