🔍 Key Concepts

• IALA Maritime Buoyage System (Region B in the U.S.) • Use of retroreflective material colors on different buoy types (safe water, preferred channel, isolated danger, special/non-lateral marks) • Difference between lateral marks and non-lateral marks (including daymarks of no lateral significance)

💭 Think About

• For each choice, recall (or sketch) its normal colors and topmarks, then ask: what color are its retroreflective panels likely to be? • Which types of marks are intended to be clearly recognized and used for nighttime navigation as part of the main channel system, and which are more informational or special-purpose? • Think about which buoy types are specifically associated with red/green navigation channels versus those associated with white and red or black and red patterns.

✅ Before You Answer

• For each option, identify whether it is lateral, safe water, isolated danger, or special/non‑lateral • Verify what color of retroreflective material is standard for lateral marks versus safe water and isolated danger marks • Double‑check which type of aid is not required to carry white retroreflective material under the IALA/US Aids to Navigation system guidance