Navigation General · Lateral Buoyage
While entering a harbor, you observe a red-and-green horizontally banded buoy with the topmost band GREEN. You should treat it as:
- AA red (starboard-hand) aid — preferred channel is to starboard of the buoy
- BA green (port-hand) aid — preferred channel is to port of the buoy✓ Correct
- CA safe water mark — pass on either side
- DAn isolated danger mark — give it wide berth on all sides
Explanation
A junction (preferred channel) buoy with the TOPMOST band GREEN (GRG) is treated as a green (port-hand) aid for the preferred channel. The preferred channel lies to the port side of the buoy (keep it to starboard to take the secondary channel).
Authority: 33 CFR 62 (U.S. ATON System)
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