Which firefighting technique involves using water to cool and extinguish a fire?

The technique of using water to cool and extinguish a fire is referred to as water application. Water is a fundamental firefighting agent that effectively reduces the heat of a fire, thereby lowering the temperature below the combustion point. This cooling effect is crucial in stopping the fire's spread and extinguishing it completely. Water also works by creating steam, which helps displace oxygen away from the flame, further assisting in extinguishing the fire.

In the context of firefighting, water application is particularly effective on class A fires, which involve ordinary combustibles such as wood, paper, and cloth. It is a widely used method due to its availability and proven effectiveness. Other methods like foam application or dry chemical suppression involve different techniques and chemicals that serve specific purposes or are tailored for particular types of fires but do not primarily focus on the direct cooling effect that water provides.