Which of the following does NOT classify as a fire extinguishment method?

The correct choice is adding a catalyst because this action does not align with the primary methods of extinguishing fires. Fire extinguishment methods generally involve removing one of the elements of the fire tetrahedron, which includes heat, fuel, and oxygen, or disrupting the chemical reaction that sustains combustion.

Removing heat is a recognized method of extinguishing fires, as it cools the burning materials and reduces the temperature below the ignition point. Removing fuel involves eliminating the combustible materials that feed the fire, and interrupting the chemical reaction means disrupting the ongoing combustion process, which can be achieved through various means, like using certain types of fire suppression agents.

On the other hand, adding a catalyst would not extinguish a fire; instead, it would typically enhance or accelerate a chemical reaction. In the context of fire, a catalyst could potentially worsen a situation rather than neutralize it. This is why it is classified as not being a fire extinguishment method.