🔍 Key Concepts
• IALA Maritime Buoyage System (International Association of Marine Aids to Navigation and Lighthouse Authorities)
• Difference between lateral marks (port/starboard) and cardinal marks (N, E, S, W of a danger)
• How light rhythms and topmarks are used to convey direction or side of safest water
💭 Think About
• Ask yourself: Do cardinal marks tell you about a side of a channel, or about where the safest water lies in relation to a danger (north, east, south, or west)?
• Which feature of a buoy could change in a way that clearly indicates north, east, south, or west—its color pattern, its topmark shape/position, or its light flashing pattern?
• Compare which choice sounds more like general identification (a label) versus something that gives you directional information about safe water.
✅ Before You Answer
• Verify that cardinal marks are used to indicate the compass quadrant (N, E, S, W) of safe water around a danger.
• Check which option relates specifically to directional orientation rather than just shape, color, or numbering.
• Make sure you are not confusing lateral marks (which use red/green and shapes for port/starboard) with cardinal marks (which reference compass directions).