How many basic types of foam are there in fire suppression systems?

In fire suppression systems, there are two basic types of foam that are primarily utilized: Class A foam and Class B foam. Class A foam is designed for use on ordinary combustible materials like wood, paper, and some plastics, focusing on enhancing water's effectiveness in extinguishing these types of fires. Class B foam, on the other hand, is formulated specifically for flammable liquid fires, such as those involving gasoline or oil. This foam works by creating a barrier over the liquid fire, suppressing vapors and preventing re-ignition.

The distinction between these two types of foam is crucial for effective firefighting, as they are each tailored to address different kinds of hazards. Understanding the specific applications of Class A and Class B foams helps firefighters choose the right solution for the situation at hand, leading to more effective fire suppression efforts.