🔍 Key Concepts

• Radiotelephone requirements for bridges in inland waters (see 33 CFR Part 117 and 33 CFR Part 26) • How mariners are notified about available radio communications and which channels to use • Difference between a sign describing information and a shape/marking acting as a signal

💭 Think About

• Which choice clearly tells a vessel that a radiotelephone is installed and how to call the bridge on the correct channel? • Look at each option: does it sound like an official information sign or more like a special day shape/signal that you’d expect in Rules of the Road? • Ask yourself: would the regulation be more concerned with displaying a shape or giving practical written information (like channel numbers) that any operator can read?

✅ Before You Answer

• Verify in 33 CFR that the requirement talks about a sign rather than a special day shape • Check whether the regulation emphasizes calling and working channels being posted for mariners • Eliminate any option that focuses mainly on a color/shape code (like yellow or black-and-white diamonds) that you have not seen in bridge radiotelephone regulations