COLREGs · Rule 35
Sound Signals in Restricted Visibility
TL;DR
Power-driven making way: 1 prolonged every ≤2 min. Power-driven underway but stopped: 2 prolonged every ≤2 min. NUC, RAM, CBD, sailing, fishing, towing: 1 prolonged + 2 short every ≤2 min. At anchor: bell rung rapidly for 5 sec every ≤1 min (50 m+ adds gong aft).
Why it shows up on the exam
Rule 35 has at least 8 distinct fog-signal patterns. The bell-then-gong combo for vessels at anchor 50 m+ is a high-frequency exam target.
Authoritative source
- 33 CFR §83.35— verbatim Inland Rule text (US Code of Federal Regulations)
- International COLREGs Rule 35 verbatim text is published by the IMO. The Inland counterpart 33 CFR §83 chunk above mirrors the international wording almost verbatim.
Inland parallel
Inland Rule 35 — Sound Signals in Restricted Visibility →More from Part D — Sound and Light Signals
Related drills
- Practise Rule 32 — Sound Signal Definitions
- Rule 33 — Equipment for Sound Signals
- Practise Rule 34 — Maneuvering and Warning Signals
- Rule 36 — Signals to Attract Attention
Drill COLREGs Rule 35
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