🔍 Key Concepts

• International sound signals in restricted visibility (fog signals) • Which vessels use one prolonged and two short blasts under the COLREGS • Differences between signals for power-driven underway, towed, and special classes of vessels

💭 Think About

• Think about which vessel categories have special status or special responsibilities in the International Rules and might therefore need a distinctive fog signal • Recall the standard fog signal for a power-driven vessel making way, and compare it to the pattern in the question • Ask yourself: is this signal normally used by the vessel that is doing the towing, the vessel being towed, or a vessel with its own stand‑alone status (like restricted, NUC, constrained, etc.)?

✅ Before You Answer

• Verify in the International Rules for sound signals in restricted visibility (COLREGS – Part D, Sound and Light Signals) which vessel(s) use one prolonged and two short blasts • Confirm the standard fog signal for a power-driven vessel underway making way and for one underway but not making way • Check which of the listed vessels, if any, share the same fog signal pattern (one prolonged and two short) with other 'special' vessels such as not under command, restricted in ability to maneuver, sailing, fishing, or towing/pushing vessels