Sound Signals

Visual boating guides, practice, and cited sources.

A learning aid — not for navigation. Rule text is reproduced from the public-domain USCG Navigation Rules. Each chart-symbol vector represents one mark and is matched to IHO INT 1 or Imray's published key; it is not a licensed production asset. Not affiliated with or endorsed by Imray, the RYA, ASA, NASBLA, IMO, or any licensing authority.

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Core content reviewed: July 15, 2026