What is most effective in putting out solvent fires?

• A. Water
• B. Foam
• C. Dry Chemical
• D. Carbon Dioxide (CO2)

Answer: (D)

For solvent fires, the fastest way to stop the flame in confined spaces is to remove the flame’s access to the air by displacing it with carbon dioxide. CO2 blankets the area quickly, knocking down the fire without leaving any residue that could damage sensitive aircraft systems or require cleanup. Water would spread the flammable liquid and potentially worsen the fire, while foam, though effective for many liquid fires, can complicate confined-space use and isn’t as immediate a knockdown in these environments. Dry chemical can extinguish solvent fires, but it leaves a powder that can contaminate equipment and systems, making CO2 the best option for quick, clean suppression in enclosed compartments. Remember, CO2 is not for open areas or large fires and can pose an asphyxiation risk, so it must be used only where occupants are safely evacuated or protected.