COLREGs · Rule 21
Definitions (Lights)
TL;DR
Defines masthead light (white, 225° forward arc), sidelights (red 112.5° port, green 112.5° starboard), sternlight (white, 135° aft), towing light (yellow, 135° aft), all-round light (360°), and flashing light (≥120 fpm).
Authoritative source
- 33 CFR §83.21— verbatim Inland Rule text (US Code of Federal Regulations)
- International COLREGs Rule 21 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 21 — Definitions (Lights) →More from Part C — Lights and Shapes
Related drills
- Rule 20 — Application (Lights and Shapes)
- Rule 22 — Visibility of Lights
- Practise Rule 23 — Power-driven Vessel Underway
- Practise Rule 24 — Towing and Pushing
Drill COLREGs Rule 21
Sign in to drill citation-backed questions on this rule with immediate feedback and the source chunk in a popover.