It's the Law: Required Equipment

Sound-Producing Devices

In periods of reduced visibility or whenever a vessel operator needs to signal his or her intentions or position, a sound-producing device is essential.

• Arizona state law does not require that vessels carry a sound-producing device; however, it is always a good idea to have one on board.
• Five (5) or more short blasts mean danger or doubt, which is very important for all boaters to remember.
• Federal law requires that vessels operating on federally controlled waters, such as the Colorado River and Lake Systems, be equipped with sound-producing device(s). On federally controlled waters:
  • Vessels less than 65.6 ft. (20 meters) in length, which includes PWCs, are required to carry on board a whistle or horn or other means to make an efficient sound signal audible for at least one-half mile.
  • Vessels that are 65.6 ft. (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-half mile.

Common Sound Signals

Some common sound signals that you should be familiar with as a recreational boater are as follows.

• A short blast lasts one second.
• A prolonged blast lasts 4-6 seconds.

Changing Direction

• One short blast tells other boaters "I intend to pass you on my port (left) side."
• Two short blasts tell other boaters "I intend to pass you on my starboard (right) side."
• Three short blasts tell other boaters "I am backing up."

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 sailing vessels.

Warning

• One prolonged blast is a warning signal (for example, used 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 or that you disagree with the other boater's intentions.