Rules of the Road · Light Definitions & Visibility
Under Rule 20, which statement regarding the use of prescribed lights and shapes is CORRECT?
- AShapes need only be displayed from sunrise to sunset✓ Correct
- BLights may never be shown during daylight hours
- CShapes shall be exhibited from sunrise to sunset and may be shown at night if necessary
- DLights shall be shown at all times, including daylight hours
Explanation
Rule 20(d) specifies that shapes shall be exhibited during daylight (sunrise to sunset). Rule 20(b) covers lights from sunset to sunrise and during restricted visibility. The two regimes are complementary: lights for darkness/poor visibility, shapes for daylight.
Authority: 72 COLREGS Rule 20(d)
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