Portable foam type fire extinguishers are most effective on（）.

A.only when fully loaded
B.if one or more tanks are full
C.when transferring cargo
D.only when the barge is being towed

A.the CO₂ being inhaled by personnel
B.reflash of burning liquids
C.vapor condensation on the extinguisher
D.the discharge causing a static spark

A.opening dead spaces to check for heat or fire
B.evacuation of the vessel
C.sounding the all clear signal
D.operation of the emergency generator