What is the primary method of extinguishing a fire by excluding oxygen?

Smothering the fire involves covering it in a way that restricts the availability of oxygen, which is one of the essential elements of the fire triangle (fuel, heat, and oxygen). When oxygen is excluded from a fire, the combustion process cannot continue, effectively extinguishing the flames. This method can be executed using various materials, such as blankets, foam, or even dirt, which create a barrier between the fire and the surrounding atmosphere.

Cooling the fuel, removing fuel, and reducing temperature are methods that can help in fire prevention or in control situations, but they do not primarily focus on the exclusion of oxygen as a direct means of extinguishment. While cooling involves lowering the temperature of the material to mitigate combustion, and removing fuel entails taking away the material that is burning, neither directly addresses oxygen exclusion. Each of these methods plays a role in fire management but does not specifically target the oxygen component as effectively as smothering does. Thus, smothering is recognized as the primary method for excluding oxygen from a fire.