How does CO2 extinguish a fire?

CO2 extinguishes a fire primarily by removing the oxygen that fuels combustion. Fire requires three elements to ignite and continue burning: heat, fuel, and oxygen, which together form what is known as the fire triangle. When CO2 is released, it displaces the oxygen in the surrounding area, effectively lowering the concentration of oxygen available for the fire to sustain itself. This reduction in oxygen levels interrupts the combustion process, causing the fire to smother and eventually extinguish.

The effectiveness of CO2 as a fire suppressant is particularly notable in certain types of fires, such as those involving flammable liquids or electrical equipment, where water or other agents may cause additional harm or create hazards. Since CO2 is non-conductive and doesn't leave residue, it becomes a practical choice for these scenarios.

Understanding the mechanism by which CO2 operates highlights its unique role in firefighting, establishing it as a crucial extinguishing agent in situations where minimizing damage and risk is essential.