How many degrees does a side light cover on a boat?

A side light on a boat is designed to cover an arc of 112.5 degrees. Specifically, this light is arranged to shine from the boat's side outwards and contributes to the visibility of the vessel when observed from other boats. The purpose of this arrangement is to provide other mariners with information about the direction the vessel is facing.

In nautical navigation, the side lights serve to indicate whether a vessel is approaching head-on or if it is moving across the path of another vessel. The 112.5-degree coverage allows for a sufficient amount of visibility to warn other vessels of their presence, while the directional nature of the light ensures that each type of navigation light (such as the side light) has a defined area that corresponds to its position.

This specific degree measurement sets side lights apart from other navigation lights, such as masthead lights or stern lights, which have different coverage angles to fulfill their unique visibility requirements in maritime navigation.