Warnings, Inland

Leaving a dock or berth

A warning that a power-driven vessel is leaving a dock or berth.

One prolonged blast

Press play. One signal at a time.

Leaving a dock or berthInland
A warning that a power-driven vessel is leaving a dock or berth.
Inland Rule 34(g), 33 CFR 83.34(g)

Who sounds it

Power-driven vessel leaving a dock or berth.

How it's sounded

Prolonged blast: 4 to 6 seconds (Rule 32(c)); 5 seconds is used here.

A short blast is about 1 second. A prolonged blast is 4 to 6 seconds. Clips use 1 and 5 seconds.

Worth remembering

Inland only. The International rules have no leaving-dock signal.

The same sound elsewhere

These use the same pattern, so the rules you’re under and the situation decide what it means.

Study more

See every sound signal, try the free Rules of the Road practice test, or read who gives way, and how Inland differs.

Learn the whole set

Helm drills every signal with flashcards and spaced review, on the web and iPhone.

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Sources

Inland Rule 34(g), 33 CFR 83.34(g)

Helm is an independent study aid, not affiliated with or endorsed by the U.S. Coast Guard or the National Maritime Center. This page is for study, not navigation guidance or legal advice. Check the current rules before you rely on anything here.