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The words “PFAS foam” can mean one of two things:

  • On lakes and streams, the movement of wind and waves can create foam that floats on top of the water or blows on shore.  This foam may or may not contain PFAS.  Learn more about this kind of foam by selecting the lake and stream photo below.
  • PFAS may also be in certain firefighting foams. These foams are most commonly known as Aqueous Film Forming Foam (AFFF) or Class B foam. Learn more about firefighting foam by selecting the firefighter photo below.

Firefighting Foam and PFAS

There are two major classes of firefighting foam: Class A and Class B. Class B is also called Aqueous film forming foam (AFFF) and is usually created using PFAS. It is a highly effective foam used for fighting high-hazard flammable liquid fires, like gasoline, oil, and jet fuel.