Question 48 MODU01 - Offshore Installation Manager

The Correct Answer is C **Explanation for Option C (Correct Answer):** Option C, "One prolonged and two short blasts at two-minute intervals," is the correct fog signal for a vessel restricted in its ability to maneuver (RAM) or a vessel **at anchor** in a restricted visibility situation, *when that vessel is not a vessel of 100 meters or more in length*. A vessel engaged in fishing while at anchor is required to sound the signal prescribed for a vessel **at anchor** (COLREG Rule 35(d)), which states: * A vessel at anchor shall, at intervals of not more than one minute, ring the bell rapidly for about 5 seconds. * In addition, a vessel at anchor may sound three distinct blasts (one short, one prolonged, and one short) to give warning of her position and the possibility of collision to an approaching vessel. However, the specific signal "One prolonged and two short blasts" (C) is the fog signal for a vessel that is **not under command (NUC)**, a **vessel restricted in its ability to maneuver (RAM)**, a **vessel constrained by its draught (CBD)**, a **sailing vessel**, a **vessel engaged in fishing (whether underway or at anchor)**, or a **vessel engaged in towing or pushing (if towing is part of the operational activity)**. COLREG Rule 35(c) dictates the signal for vessels not under command, restricted in their ability to maneuver (including fishing operations), and other specific types: > A vessel **not under command**, a **vessel restricted in her ability to manoeuvre**, a **vessel constrained by her draught**, a **sailing vessel**, a **vessel engaged in fishing** and a vessel engaged in towing or pushing shall, at intervals of not more than two minutes, sound **one prolonged blast followed by two short blasts.** Since a vessel engaged in fishing is specifically mentioned under Rule 35(c), regardless of whether it is underway or temporarily at anchor, it must use this operational signal, which supersedes the general "vessel at anchor" signal (unless the fishing vessel is greater than 100 meters, which would require the bell and the optional whistle signal). This signal is sounded at intervals not exceeding two minutes. *** **Explanation of Incorrect Options:** **A) A rapid ringing of the bell for five seconds at one-minute intervals:** This is the primary signal for a vessel **at anchor** (COLREG Rule 35(d)) that is less than 100 meters in length. While the vessel is technically at anchor, its operational status as a "vessel engaged in fishing" requires the specific whistle signal detailed in Rule 35(c), making (C) the required answer. **B) One prolonged and three short blasts at two-minute intervals:** This is the optional signal used by a pilot vessel when engaged on pilotage duty (COLREG Rule 35(k)). **D) A sounding of the bell and gong at one-minute intervals:** This combination (bell in the fore part and gong in the after part) is the required signal for a vessel **at anchor** that is **100 meters or more in length** (COLREG Rule 35(e)).