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.

Vessels 12 meters or more in length are required to carry on board a whistle or horn, and a bell.

Any vessel less than 12 meters in length may carry a whistle or horn, or some other means to make an efficient sound signal to signal your intentions and to signal your position in periods of reduced visibility.

Therefore, any vessel less than 12 meters in length is required to make an efficient sound signal to signal your intentions and to signal your position in periods of reduced visibility.

Signaling Devices 

For the CME, the Auxiliary requires some type of horn or whistle capable of a 4 second blast audible for 1/2 mile for all boats. (Athletic whistles are not acceptable on boats over 12 meters.)