Exam frequency
85%
Difficulty
2/5
Drill questions
48
Authoritative sources
Every answer on this topic traces back to the public rule corpus below.
Source excerpts
Bowditch Ch. 5 §501
Bowditch Ch. 5 §501 — Short Range Aids to Navigation Aids to navigation include lights, buoys, beacons, and electronic aids. The US lateral system follows IALA-B: red on the right returning from sea, even numbers on red, odd on green.
33 CFR §62.21
§ 62.21 General. (a) The navigable waters of the United States and non-navigable State waters after December 31, 2003, are marked to assist navigation using the U.S. Aids to Navigation System, a system consistent with the International Association of Lighthouse Authorities (IALA) Maritime Buoyage System. The IALA Maritime Buoyage System is followed by most of the world's maritime nations and will improve maritime safety by encouraging conformity in buoyage systems worldwide. IALA buoyage is divided into two regions made up of Region A and Region B. All navigable waters of the United States follow IALA Region B, except U.S. possessions west of the International Date Line and south of 10 degrees north latitude, which follow IALA Region A. Lateral aids to navigation in Region A vary from tho…
Light List — light-characteristic (G)
Light List — light-characteristic (G) Green (light colour) (G) Green is used on starboard-hand lateral aids in IALA-B.
Light List — light-characteristic (R)
Light List — light-characteristic (R) Red (light colour) (R) Red is used on port-hand lateral aids in IALA-B (US, Canada, Japan, Caribbean, Korea, Philippines).
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A mariner is approaching a US port at night and observes a flashing green light on a buoy bearing 045° T. Applying IALA-B rules, what action is consistent with safe navigation if the vessel is inbound?
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