What should be done if cabin air quality is compromised during a flight?

If cabin air quality is compromised during a flight, the correct action is to prepare to use oxygen masks and inform passengers. This procedure is critical because compromised air quality can result from various factors, such as smoke, toxic fumes, or other contaminants that may pose serious health risks to passengers and crew. By preparing the oxygen masks for use, the flight crew ensures that passengers can receive adequate oxygen in case the compromised air quality affects their ability to breathe normally.

Informing passengers is equally important; it helps to maintain calm and provides them with necessary instructions on how to use the oxygen masks if needed. Clear communication from the flight crew helps to reduce panic and ensures that everyone understands the situation and what steps to take if the situation worsens.

The other options, while they may seem relevant, do not address the immediate safety needs of the passengers and crew as effectively. For instance, patching the air supply system may not be feasible during a flight and would take time, during which air quality could deteriorate further. Adjusting cabin pressure could also be an unsafe maneuver if air quality is already compromised, as it might exacerbate the problem. Finally, closing off sections of the cabin could restrict airflow to those areas and is not an appropriate or safe response to compromised