Sound Signals

---

So that skippers can communicate, sound signals are used. They consist of short and long tones. The pause between tones is 1 second long.

A short tone (●) is about 1 second long, a long tone (▬) about 4 seconds long.

Signal	Meaning
●	I am altering my course to starboard
● ●	I am altering my course to port
● ● ●	My engine is going astern
● ● ● ●	I am unable to manoeuvre
▬	Attention, I am holding my course; harbour exit signal; fog signal (except right-of-way vessels); bridge passage signal
▬ ▬	Fog signal of right-of-way vessels
▬ ▬ ▬	Harbour entry signal of right-of-way vessels, towing convoys, and vessels in distress
Series of long tones	Distress signal
● ● 3 times per minute, or ringing of bells	Fog signal of harbours, landing stages, and fog warning installations