Which type of nozzle is designed to reduce the supply of oxygen while extinguishing fire?

Fog applicators are designed to create a fine spray of water droplets that reduce the supply of oxygen while extinguishing a fire. This mechanism works by generating a mist that can cover a larger surface area and simultaneously absorb heat, making it effective for cooling burning surfaces. The finely divided water particles also disrupt the combustion process by displacing oxygen around the fire, thereby aiding in its suppression.

In contrast, high pressure nozzles are primarily focused on delivering water at a higher velocity, which can be beneficial for penetrating deeper into fire but does not inherently reduce oxygen levels in the surrounding area. Low pressure nozzles generally provide a steady stream of water but lack the dispersion needed to effectively manage oxygen supply. Water gun nozzles serve similar purposes as low pressure nozzles, leading to direct application without the oxygen-depleting effects associated with fog applicators.

Therefore, fog applicators are the best choice due to their unique ability to combat fire by both cooling the environment and limiting oxygen availability.