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單項選擇題

Regulations require that cargo tanks carrying grades D or E liquids on tank barges be vented with（）.

A.gooseneck vents and flame screens
B.pressure-vacuum relief valves
C.branch vent lines and a vent header
D.forced draft blowers

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單項選擇題

Regulations require that cargo pumps in tankers carrying grade D liquid cargo shall be isolatedfrom sources of vapor ignition by（）.

A.cofferdams
B.gastight bulkheads
C.passageways or living quarters
D.general cargo spaces

單項選擇題

Regulations require that cargo pumprooms on tank barges (constructed in 1965) carrying grades B or C liquid cargoes have power ventilation systems which can completely change the air in （）.

A.1 minute
B.3 minutes
C.5 minutes
D.10 minutes