Coast Guard Exams
Question 98Safety & Environmental - Assistant Engineer70% to pass

After ballasting a fuel tank, which of the listed valves should you close FIRST?

AI Explanation
The correct answer is A) Sea suction valve. When ballasting a fuel tank, the sea suction valve should be closed first to prevent water from entering the fuel system. This is a critical safety measure to avoid contaminating the fuel. The tank manifold filling valve, deck filling valve, and pump discharge valve are all downstream of the sea suction valve, so closing the sea suction valve first isolates the tank from the sea and prevents unintended water intake. The other answer choices do not address the primary risk of water contamination, which is why A) is the correct answer.