Question 169Safety & Environmental - QMED

The correct answer is C) the machine is not inside the tank. When using portable tank cleaning machines, the hoses should only be disconnected when the machine is not inside the tank. This is a safety precaution to prevent the release of hazardous vapors or liquids during the disconnection process. Disconnecting the hoses while the machine is inside the tank could expose the operator to potential safety risks. The other options are incorrect because: A) partially draining the hose does not make it safe to disconnect, and B) having a sailor standing by the machine does not eliminate the need for the machine to be outside the tank before disconnecting the hoses.