What action should be taken first upon finding a clandestine laboratory on a vessel?

The most appropriate initial action when discovering a clandestine laboratory on a vessel is to remove all personnel from the vessel. This approach prioritizes safety and minimizes the risk of exposure to potentially hazardous materials or dangerous situations that may arise from the laboratory. By securing the area and ensuring that no one is in immediate danger, responders can better assess the situation without interference or risk from personnel who may not be aware of the dangers.

Taking this action also allows authorities to properly evaluate the lab without external disruptions and ensures that any evidence or hazardous materials can be safely handled. This method of handling such a discovery adheres to protocols that stress the importance of safety and effective response to hazardous situations. Removing personnel protects them from potential harm and allows for a more thorough investigation of the lab without the complications that come from having individuals present.