Which extinguishing method primarily relies on the removal of oxygen to extinguish flames?

The extinguishing method that primarily relies on the removal of oxygen to extinguish flames is smothering. This technique involves covering a fire with a material that prevents oxygen from reaching the flames. By suffocating the fire, smothering effectively disrupts the oxygen supply necessary for combustion to continue.

This method is particularly effective for certain types of fires, such as grease or oil fires, where traditional means (like water) might be ineffective or could intensify the blaze. Smothering can be accomplished through various materials, such as blankets, sand, or specialized fire suppression agents that envelop the fire and create a barrier to the surrounding air.

The other methods, while valid in their own rights, rely on different principles. Cooling involves reducing the temperature of the fire, which can extinguish flames by lowering the heat to below the ignition point. Interrupting chain reactions focuses on breaking the chemical processes that sustain combustion, and removing fuel entails eliminating any material that can burn. However, none of these methods specifically target the removal of oxygen as smothering does.