The navigation rules require sound signals to be made under certain circumstances. Meeting, crossing and overtaking situations described in the Navigation Rules section are examples of when sound signals are required. Recreational vessels are also required to sound signals during periods of reduced visibility. The requirement to carry a bell in international waters was recently dropped.

1. Every motorboat of 16 feet and greater must be equipped with an efficient whistle or other mechanical appliance that produces sound.
2. Every motorboat of class 26 feet or greater must be equipped with an efficient bell.
3. The provisions of this section do not apply to motorboats while competing in a sanctioned race or, if the boats are designed and intended solely for racing, while engaged in navigation incidental to the tuning up of the boats and engines for a race.