The Basics of Boat Sound Signals
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There are several occasions on a boat when you need to use sound signals. In particular, when visibility is limited, boat sound signals are of the utmost importance. Other boaters need to be aware of where you are and what you’re doing at all times. Learning what these sound signals mean and how to use them will keep you and other boaters safe. It will also greatly improve your boating experience. Safety is always key.
How are sounds and signals made on your boat?
There are two ways to alert other vessel with a sound producing device. You can either blast the horn or use a stroke of your bell. Depending on the situation you will need to use one or the other. Learning this is part of the rules of the road.
If your boat is less than 39.4 feet it must carry something able to produce an adequate sound. That could be a bell, a whistle, or an air horn. Remember, in an emergency situation, anything that makes a sound will do. As long as you and other vessels can hear each other. However, you should have the legal equipment on board and in good working order.
If your vessel is between 39.4 Ft and 65.6 feet you must have a whistle and a bell. The whistle has to be able to produce a sound that can be heard up to half a mile away. The mouth of the bell has to be at least 7.87 in in diameter. These are legal requirements and part of inland rules.
When do you make sound signals on your boat?
You only need to use a sound signal when you are in sight of another vessel. If you’re going to meet or cross at a distance of one another within 1/2 a mile you need to signal. These signals are not to be used when visibility is limited by fog. There are different signals to be used with restricted visibility.
When you are approaching another vessel and wish to get around them these are the maneuvering signals you should use. A short whistle blast is typically 1 second in duration.
One Short Blast: One short blast means you intend to pass a vessel on your port side.
Two Short Blasts: Two short blasts signals your intent to pass the vessel on your starboard side.
A handy tip or remembering which signal to use is 1 short blast for one syllable equals port. Two short blasts for two syllables equals starboard.
These are signals to alert other boats that there is something they need to be aware of. Unlike a short blast of one second, a prolonged blast should last four to six seconds.
Three Short Blasts: 3 short blasts means you are backing up. You are operating astern propulsion now.
Five Short Horn Blasts: Danger. Or you do not understand the approaching boat’s intentions and they need to clarify. These need to be rapid blasts so they are not confused with prolonged blasts.
One Prolonged Blast: Warning. Use this to indicate when you are leaving a dock or berth. Can also be used as a warning when you are approaching an obstruction, or a blind to turn.
One Prolonged Blast Repeated Every 2 Minutes: Use this when you are in a power driven vessel with limited visibility. If you were travelling through fog, you would do this.
One Prolonged Blast Plus 2 Short Blasts Repeated Every 2 Minutes: This indicates you are in a sailing vessel in limited visibility.
Limited Visibility Signals
If conditions are such that you cannot see other boaters than use these signals.
2 Prolonged Blasts Repeated Every 2 Minutes: This warning signal is used when you are in a power driven vessel that has stopped. You are not anchored but you are not making way.
Five Seconds of Rapid Bell Ringing: When your vessel is at anchor, ring the bells rapidly for 5 seconds at intervals of 1 minute.
3 Bell Strokes + 5 Seconds of Rapid ringing + 3 Bell Strokes: When your vessel is aground, ring the bell three times then rapidly ring for 5 seconds, and ring three times again. This must be repeated every minute
Things to Remember
When you hear a warning from another boat you must respond accordingly. This is especially important when you are in limited visibility. If you’re unable to see each other but can hear the signals from the other vessel, slow down. Continue at a minimum speed and proceed with caution. Maintain a lookout until you are no longer in range of the other vessel. The rules of the road always favor safety. Your signals must be clear, especially when other boats are not in sight.
Always signal your intent when maneuvering a vessel. Remember that directions are based on the vessel making the signal. So when another boat sounds a short blast it means they intend to pass on their port side. Likewise, if your intent is to pass you will use one short blast to indicate your port side. Two blasts to indicate your starboard side. The same signals are needed when overtaking boats as well. That means from either the port side or the starboard side. Always make sure the other vessel knows how you are maneuvering.
Signals are a method of communication. When a boat signals a proposed maneuver, you need to respond. Reply with the same signal to indicate you have understood their intent. If you are unclear, reply with a danger signal of five or more short blasts so they know you do not understand. They should signal again to clarify.
When in doubt, sound the danger signal. It’s always better to be safe than sorry. Power driven vessels have a much longer reaction time. In limited visibility, you need to be as clear as possible. You can sound 5 short blasts any time to indicate you are unclear of another vessel’s intentions.