What is the primary use of a water extinguisher?

A water extinguisher is specifically designed to combat ordinary combustibles, which include materials such as wood, paper, and textiles. The effectiveness of water as an extinguishing agent lies in its ability to cool the flames and reduce the heat to a level where combustion can no longer be sustained. By soaking the burning material, water helps to eliminate the fire's heat, which is one of the three essential components of the fire triangle: heat, fuel, and oxygen.

Water extinguishers are not suitable for fires involving electrical equipment or flammable liquids, which could be dangerous and ineffective using water as a means of suppression. For instance, using water on an electrical fire can create a risk of electrical shock, while applying it to flammable liquids can spread the fire rather than extinguishing it. Similarly, for chemical fires, specific extinguishers designed for neutralizing those substances are required to safely and effectively handle them.