【单选题】You have water washed your cargo tanks using the fixed machines.What should you do before using portable machines to clean areas screened from the wash of the fixed machine by structural members _____...
A.
Ventilate the tank to eliminate any electrostatically charged mist
B.
Attach the water supply hose to the portable machine after the cleaning head is positioned inside the tank
C.
Insure that the tanks are not stripped until the final wash is started
D.
Ground the fixed machines to eliminate any electrostatic buildup on the cleaning head