Table of Contents

Download the PDF Version

It's the Law

Sound-Producing Devices


Vessels less than 65.6 feet (20 meters) 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 (20 meters) 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.

Some sound signals that you should be familiar with are:

Restricted Visibility

  • One prolonged blast at intervals of not more than two minutes is the signal used by power-driven vessels when underway.
  • One prolonged blast plus two short blasts at intervals of not more than two minutes is the signal used by sailboats under sail.

Warning

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