🔍 Key Concepts

• Drawbridge sound signals under the Inland Navigation Rules (33 CFR Part 117) • Meaning of the request-for-opening signal (prolonged + short blast pattern) • Whether each drawbridge operator needs a separate signal or can rely on communication from another bridge

💭 Think About

• Ask yourself: Does the regulation say that one bridge operator is responsible for informing another, or that vessels must signal each bridge they want opened? • Consider whether repeating a standard signal in succession changes its meaning in the regulations, or if that would be an improvised signal not described in the rules. • Think about what adding an extra signal (like two prolonged blasts after the opening request) would mean—does that combination appear anywhere in the drawbridge rules?

✅ Before You Answer

• Verify in 33 CFR Part 117 – Drawbridge Operation Regulations what the standard sound signal is for requesting a bridge opening. • Check whether the rules describe any special sound for indicating passage through multiple closely‑spaced bridges, or if the standard request is simply used for each bridge as needed. • Confirm if any answer choice depends on a bridge operator automatically notifying another bridge; verify whether that is actually stated in the regulations.