Rules of the Road · NUC / RAM / Constrained by Draft
A vessel engaged in dredging or underwater operations, when underway and making way, shows in addition to the RAM lights:
- ATwo all-round red lights on the obstruction side and two all-round green lights on the clear side✓ Correct
- BA flashing red light on the obstruction side
- CAn all-round white light on the side where vessels may pass
- DA yellow diamond shape
Explanation
Rule 27(d) requires a dredging or underwater operations vessel to show two all-round red lights vertically on the side where the obstruction exists and two all-round green lights vertically on the side where passing is safe. Red means restricted passage; green means go.
Authority: 72 COLREGS Rule 27(d)(i) and 27(d)(ii)
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