Question 46 TK02 - Tank Vessel Assistant - Liquefied Gas

The Correct Answer is B **Why Option B ("a pneumatically or mechanically operated device") is correct:** This requirement is mandated by U.S. Coast Guard regulations found in **33 CFR 154.550 (f)**, which covers communications and monitoring during oil transfer operations. The regulation states that for all loading operations, the terminal must supply the vessel with a means by which the vessel's designated person in charge may stop the flow of oil to the vessel. This means must be reliable and capable of ensuring immediate shutdown. A signal board, sequence of lights, or loudhailer relies on human interpretation and action by personnel at the terminal to stop the pumps, which introduces delay. A **pneumatically or mechanically operated device** (such as a remote shutoff valve control or an emergency stop button that directly triggers the terminal's emergency shutdown system) provides a direct, immediate, and physical mechanism for the vessel's person in charge to stop the flow of oil, meeting the immediate shutdown requirement necessary to mitigate major spills like those caused by hose rupture or tank overflow. **Why the other options are incorrect:** * **A) a signal-board on the bridge:** This relies on visual signaling, which is prone to misinterpretation, delays, or being missed entirely, especially during adverse conditions or emergencies. It does not provide the immediate, physical control required for emergency shutdown. * **C) a specific sequence of lights:** Similar to a signal board, this is an indirect method of communication (a signal) that requires a terminal operator to receive, understand, and then execute the shutdown. It lacks the immediacy and reliability of a physical control mechanism. * **D) a loudhailer from the vessel bridge:** Using a loudhailer is a voice command method that is highly susceptible to noise interference, distance, and miscommunication. Furthermore, it depends entirely on the response time of the personnel at the terminal pump station and cannot guarantee the **immediate** shutdown capability required by the regulation.