🔍 Key Concepts

• Aids to Navigation (ATONs) and whether every lighted aid is part of the lateral system • Special uses of lights on the Western Rivers (U.S. inland rivers) and what kinds of marks may show white lights • Contents and purpose of the U.S. Coast Guard Light List and what types of structures it includes

💭 Think About

• Ask yourself: Does every lighted buoy or marker always indicate port/starboard sides of a channel, or can some lighted aids have no lateral significance (for example, safe water, special purpose, or isolated danger marks)? • Think about Western Rivers: Where would you expect to see white lights—on range/crossing marks, or only on red/green lateral buoys? • Consider what the Light List is used for: Is it limited to buoys and beacons, or does it also include fixed offshore structures like oil platforms that display lights?

✅ Before You Answer

• Verify whether all lighted aids are part of the lateral system, or if some are non‑lateral aids with lights. • Check if Western Rivers crossing marks are specifically described as exhibiting white lights in inland waterway references. • Confirm whether oil well or drilling structures that are lighted are listed as individual entries in the U.S. Light List.