Question 18 MODU01 - Offshore Installation Manager

The Correct Answer is A. **Explanation for A (A vessel constrained by her draft):** Rule 28 of the COLREGs (International Regulations for Preventing Collisions at Sea) specifies the lights for vessels constrained by their draft (CBD). A vessel constrained by her draft shall exhibit, in addition to the lights required for a power-driven vessel of her length, **three all-round red lights in a vertical line** where they can best be seen. These three vertical red lights signify to other mariners that the vessel is restricted in its ability to deviate from its course due to its draft and the available navigable water. **Why the other options are incorrect:** **B) A vessel moored over a wreck:** A vessel engaged in salvage or diving operations (which may involve being moored over a wreck) would typically display three all-round lights in a vertical line, but they are **red-white-red** (Red light/White light/Red light), not three red lights. **C) A vessel aground:** A vessel aground exhibits the lights for a vessel at anchor (a forward white anchor light, and an aft white anchor light if 50m or more in length) and, in addition, **two all-round red lights in a vertical line** where they can best be seen. It displays two red lights, not three. **D) A vessel dredging:** A vessel engaged in dredging or underwater operations (a type of vessel restricted in its ability to manoeuvre) displays three all-round lights in a vertical line, but they are **red-white-red** (Red light/White light/Red light). Furthermore, it also displays two vertical green lights on the side where the obstruction lies and two vertical red lights on the side on which another vessel may pass. It does not display three vertical red lights as its primary identifying signal.