Question 47 OSV01 - Master/Chief Mate - Offshore Supply Vessels

The Correct Answer is D **Why Option D ("One prolonged followed by three short blasts") is correct:** The fog signals for vessels are governed by the International Regulations for Preventing Collisions at Sea (COLREGs), Rule 35 (Sound Signals in Restricted Visibility). Rule 35(e) specifically addresses the signal for a vessel being towed or for a manned vessel being pushed ahead or alongside. A manned vessel being towed must sound a signal of: **one prolonged blast followed immediately by three short blasts**. This signal must be sounded at intervals of not more than 2 minutes. This combination is required under both the International and Inland rules (the Inland rules typically reference the International standards for this specific signal). **Why each of the other options is incorrect:** * **A) One prolonged followed by two short blasts:** This is the required fog signal for a **power-driven vessel underway but stopped and not making way** (Rule 35(b)). It is also the signal for a vessel **restricted in her ability to maneuver** (Rule 35(c)). * **B) Two prolonged blasts:** This is the required signal for a **sailing vessel** (Rule 35(c)). * **C) One prolonged followed by one short blast:** This signal is not defined in Rule 35 for a specific type of vessel. However, one prolonged blast is the signal for a **power-driven vessel underway and making way** (Rule 35(a)). A signal of one prolonged followed by one short blast is an **inland** rule requirement for a vessel *at anchor* warning of her position or warning of the possibility of collision.