Which method interrupts the chemical chain reaction during a fire?

The method that interrupts the chemical chain reaction during a fire is chemical flame inhibition. This approach involves using substances that chemically interfere with the combustion process. Specifically, inhibitors target the free radicals generated during combustion, effectively disrupting the chain reaction necessary for fire to continue burning.

In contrast, other methods such as cooling and smothering work through different mechanisms. Cooling involves the removal of heat, effectively bringing the temperature below the ignition point, while smothering deprives the fire of oxygen, preventing it from sustaining combustion. Saponification, on the other hand, is a chemical reaction typically associated with the transformation of fats into soap and does not directly address the interruption of the fire's chemical chain reaction.

Understanding these distinctions is crucial for effective fire suppression, and recognizing chemical flame inhibition provides insight into advanced firefighting techniques.