🔍 Key Concepts

• Bridge lighting for navigational channels at night under 33 CFR Part 118 (Bridge Lighting and Other Signals) • Difference between center-channel span signals and individual pier or drawbridge signals • How white vs. red vs. green lights are typically used to indicate preferred or safe passage

💭 Think About

• Think about what kind of light pattern would clearly mark the safest, primary span for vessels to pass under in darkness. • Compare which options look more like standard fixed bridge channel markings versus floating aids like buoys or beacons. • Ask yourself which choice seems designed to be visible from a distance and to distinguish the main navigational span from secondary spans.

✅ Before You Answer

• Verify how main channel spans on fixed bridges are marked differently from adjacent or secondary spans. • Check whether a quick flashing red or green is normally used on a bridge structure or on a floating aid to navigation like a buoy or lighted beacon. • Confirm which color(s) and arrangements of lights are typically associated with safe center of channel passage rather than with lateral marks (port/starboard) or special-purpose lights.