Which statement about CO2 extinguishing is true?

Which statement about CO2 extinguishing is true?

• A. It is ideal for all classes without risk
• B. It can present suffocation hazard to personnel in confined areas
• C. It leaves a heavy residue that damages equipment
• D. It displaces fuel from the fire

Answer: (B)

CO2 extinguishing works by flooding the area with carbon dioxide, which is denser than air and displaces oxygen. This starves the flame of the oxygen it needs to burn, making it effective for electrical/equipment fires and other situations where water or foam could cause damage. But because it reduces the amount of breathable air, anyone in a confined space can asphyxiate, so CO2 systems must be used only in unoccupied or appropriately isolated areas with precautions in place. That’s why the true statement is that it can present a suffocation hazard to personnel in confined areas. CO2 does not leave a heavy residue, and it does not displace fuel from the fire.

CO2 extinguishing works by flooding the area with carbon dioxide, which is denser than air and displaces oxygen. This starves the flame of the oxygen it needs to burn, making it effective for electrical/equipment fires and other situations where water or foam could cause damage. But because it reduces the amount of breathable air, anyone in a confined space can asphyxiate, so CO2 systems must be used only in unoccupied or appropriately isolated areas with precautions in place. That’s why the true statement is that it can present a suffocation hazard to personnel in confined areas. CO2 does not leave a heavy residue, and it does not displace fuel from the fire.