It's the Law: Required Equipment

Sound-Producing Devices

Vessels less than 65.6 feet in length, which includes PWCs, are required to carry on board a whistle or horn or some other means to make an efficient sound signal audible for at least one-half mile.

Vessels that are 65.6 feet or more in length are required to carry on board a whistle or horn, and a bell that are audible for at least one mile.

Common Sound Signals

Restricted Visibility

• One prolonged blast at intervals of not more than two minutes is the signal used by powerboats underway.
• One prolonged blast plus two short blasts at intervals of not more than two minutes is the signal used by sailboats under sail alone.

Warning

• One prolonged blast is a warning signal (for example, when coming around a blind bend or exiting a slip).
• Five (or more) short, rapid blasts signal danger or signal that you do not understand the other boater’s intentions.