What action should you take if a spill (such as overflow) occurs on a commercial vessel?

When a spill occurs on a commercial vessel, the appropriate action to take is to plug the scuppers. This action is crucial as scuppers are drainage holes that allow water (and potentially contaminants) to drain off the deck. If a spill occurs, plugging these scuppers helps prevent the spilled substance from entering the water, thereby mitigating environmental damage and adhering to pollution regulations. It is an immediate response that can help contain the spill and control the situation.

Other actions, while they may seem relevant in a spill scenario depending on the circumstances, do not address the immediate need for containment. For example, pumping the bilge may not address the source of the spill and could exacerbate the situation by displacing the spill into the water. Notifying the Coast Guard is a necessary step, especially for significant spills, but is not an immediate containment measure. Evacuating the vessel may be required in emergencies but does not directly address the management of the spill itself. Therefore, plugging the scuppers is the most effective first response to contain a spill on a commercial vessel.