What is a key characteristic of wetting agents used in fire extinguishment?

Wetting agents are specially formulated substances that enhance the effectiveness of water in extinguishing fires. A key characteristic of these agents is their ability to penetrate surfaces, especially those that are porous or have a high surface tension, such as wood, that would otherwise resist the absorption of water. By lowering the surface tension of water, wetting agents enable it to spread more easily and saturate materials, thereby penetrating deeper into the fuel source and promoting more effective extinguishment.

This penetration helps to cool the material more efficiently and reduces the risk of re-ignition. Proper application of wetting agents can significantly improve fire suppression in certain types of fires, particularly those involving combustible solids and certain types of cooking oils.