What actions should be taken if a passenger is smoking in the lavatory?

When a passenger is smoking in the lavatory, it is crucial to immediately inform the captain and follow company protocols. This action is essential for several reasons. Smoking in the lavatory poses a significant safety hazard due to the potential for fire, which can endanger everyone on board. Flight crews are trained to prioritize safety above all else, and notifying the captain ensures that the situation is addressed with the urgency it deserves.

Following company protocols also provides a structured response that aligns with FAA regulations and airline policies, ensuring that all necessary steps are taken to manage the situation properly. This might include making announcements, involving the cabin crew in monitoring the situation, or preparing for emergency procedures if needed. The captain is in charge of the aircraft's safety and will assess the situation and decide on the appropriate course of action.

The other options are less effective because encouraging the passenger to stop may not be enough to resolve the issue, ignoring the behavior can put the flight at risk, and asking other passengers to intervene could escalate the situation and create further safety concerns. Thus, informing the captain and adhering to established protocols is the best course of action in this scenario.