When should you consider using a second extinguisher after the first has been used?

• A. After the first extinguisher is depleted.
• B. Only if the captain instructs.
• C. If the fire is not controlled or re-ignition is possible, following SOP.
• D. Never use a second extinguisher.

Answer: (C)

When tackling an onboard fire, you treat extinguishing as a process, not a single act. After applying the first extinguisher, you must assess whether the fire is under control. If the fire is not controlled or there’s a risk of re-ignition, you should consider using a second extinguisher, strictly following the aircraft’s standard operating procedures. This approach reflects that some fires may smolder or hidden hotspots remain even after the visible flames are suppressed, so a second application helps ensure full control and reduces the chance of reignition.

It’s not simply about depletion of the first extinguisher, and it isn’t correct to wait for the captain’s instruction as the sole trigger—the SOP provides the defined criteria for when a second extinguisher is needed. Nor is it correct to say never use a second extinguisher; in many scenarios, multiple extinguishers are required to fully suppress the fire.