COLREGs · Rule 7
Risk of Collision
Last verified: 2026-05-16
TL;DR
Every vessel shall use all available means to determine if risk of collision exists. If there is any doubt, such risk shall be deemed to exist. Compass bearings of an approaching vessel are the canonical method.
Why it shows up on the exam
Rule 7 is the source of the 'constant bearing, decreasing range' (CBDR) test. Watch for questions where the bearing is changing slowly toward the bow — still risk of collision for very large vessels at close range.
Authoritative source
Source links checked against the current public rule corpus on 2026-05-16.
- 33 CFR §83.07— verbatim Inland Rule text (US Code of Federal Regulations)(retrieved 2026-05-16)
- International COLREGs Rule 7 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 7 — Risk of Collision →More from Part B-I — Conduct in Any Visibility
Related drills
Drill COLREGs Rule 7
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