| You are planning to use the crude oil washing system on your tankship. What is required to prevent electrostatic buildup in the tanks? |
| A) The portable machines must be set at the proper drop for the first wash before the fixed machines are used. |
| B) The source tank for the tank cleaning machines must have least one meter decanted from it. |
| C) The inert gas system must reduce the oxygen content in the tanks to a maximum of 18%. |
| D) The fixed machines must be operated simultaneously with the portable machines to equalize the electrostatic potential. |
