COLREGs glossary
Plain-English summaries of every rule from the 1972 International Regulations for Preventing Collisions at Sea. No account needed. Tap any rule for the definition.
Part A, General
Part B/I, Conduct in any condition of visibility
Part B/II, Conduct of vessels in sight of one another
Part B/III, Conduct in restricted visibility
Part C, Lights and shapes
- R20Application (lights & shapes)
- R21Definitions (lights)
- R22Visibility of lights
- R23Power-driven vessels underway
- R24Towing and pushing
- R25Sailing vessels underway and vessels under oars
- R26Fishing vessels
- R27Vessels not under command or restricted in their ability to manoeuvre
- R28Vessels constrained by their draught
- R29Pilot vessels
- R30Anchored vessels and vessels aground
- R31Seaplanes
Part D, Sound and light signals
Part E, Exemptions
Part F, Verification of compliance
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