If extinguishers have been used and the space remains pressurized, what action should be taken if possible?

• A. Open vents
• B. Fuel supply
• C. Ventilation
• D. Seal compartments

Answer: (C)

Ventilation is used to purge a space after extinguishing a fire. When extinguishers have been discharged, the space can still contain extinguishing agents, smoke, and heated gases that displace oxygen and create a hazardous atmosphere. Ventilating moves air through the space, pushing out the dangerous gases and bringing in fresh air, which helps restore a breathable atmosphere and normal pressure. Opening vents alone can help, but actively ventilating (using natural flow or a blower) ensures the contaminated air is actually removed. Sealing compartments would trap the gases, and leaving fuel supplies in place could risk re-ignition.