Which of the following represents an emergency procedure used to stop the oil flow aboard tank vessels, of 250 tons or greater, as required by U.S. regulations?

Correct Answer: Option C — Quick-acting power actuated valve

33 CFR 155.780 requires tank vessels of 250 gross tons or greater to be equipped with a quick-acting power-actuated valve to stop oil flow in an emergency. This system allows for the rapid, remote isolation of the cargo manifold, minimizing the volume of oil spilled during a hose rupture.