Small vessel rules, International and Inland
Vessels under 12 meters
May skip all the Rule 35 signals, but then must make some other efficient sound signal.
Who sounds it
Vessel of less than 12 meters.
How it's sounded
No fixed pattern. Any efficient sound signal.
At intervals of not more than 2 minutes.
A short blast is about 1 second. A prolonged blast is 4 to 6 seconds. Clips use 1 and 5 seconds.
Worth remembering
Under 12 meters isn't "no signal". It must still make some efficient sound signal.
More in small vessel rules
Study more
See every sound signal, try the free Rules of the Road practice test, or read who gives way, and how Inland differs.
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