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Underwater operations Navigation Lights
RAM — dredging / underwater ops, obstruction to starboard
All vessels
Rule Reference
Rule 27(d): a vessel engaged in dredging or underwater operations, when restricted in her ability to manoeuvre, shall exhibit the lights and shapes in (b)(i),(ii),(iii) and, when an obstruction exists: two all-round red lights or two balls on the side of the obstruction; two all-round green lights or two diamonds on the side another vessel may pass; at anchor, these lights or shapes instead of Rule 30.
Top-Down View
Tap any light dot to see its COLREGS sector and rule.
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