Question 45 OSV01 - Master/Chief Mate - Offshore Supply Vessels

The Correct Answer is B **Explanation for Option B (One prolonged blast) being correct:** According to both the International Regulations for Preventing Collisions at Sea (COLREGS Rule 34(e)) and the Inland Navigational Rules (Inland Rule 34(e)), a vessel nearing a bend or an area of a channel or fairway where other vessels may be obscured by an obstruction is required to sound **one prolonged blast** (a blast lasting 4 to 6 seconds). This signal serves as a warning of the vessel's approach. If the vessel hears a responsive signal (one prolonged blast) from a vessel around the bend, they are required to exchange passing signals upon coming in sight of each other. **Explanation of why other options are incorrect:** * **A) One short blast:** This signal (approximately one second in duration) is used to indicate a maneuver when vessels are in sight of one another. Under COLREGS, it means "I intend to alter my course to starboard." Under Inland Rules, it means "I intend to leave you on my port side." It is not the signal prescribed for approaching an obscured bend. * **C) Two short blasts:** This signal indicates a different maneuver when vessels are in sight of one another. Under COLREGS, it means "I intend to alter my course to port." Under Inland Rules, it means "I intend to leave you on my starboard side." It is not the signal prescribed for approaching an obscured bend. * **D) One long blast:** While the term "prolonged blast" is often colloquially referred to as a "long blast," the official regulation uses the specific term "prolonged blast" (4-6 seconds). More importantly, the signal "one long blast" (a blast of 4 to 6 seconds) is also the required signal for a power-driven vessel making way in restricted visibility (COLREGS Rule 35(a)), or the signal for vessels leaving a dock or berth (Inland Rule 34(g)). While a prolonged blast is the correct length, using the distinct official terminology (B: One prolonged blast) is the most accurate regulatory description for the specific action of approaching a bend.