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Firefighting foam and PFAS

A firefighter spraying bright white foam at a fire

Firefighting foam and PFAS

The two major classes of Firefighting Foam: Class A and Class B. Some fire stations may have only Class A foam, some fire stations may have both Class A and Class B foam.

Class A foam

Class A foam is used to extinguish Class A materials, such as wood, paper, brush and vegetation (wildland), is widely used by many fire departments for structural firefighting using compressed air foam systems.

Class B foam (also called 'aqueous film forming foam', or AFFF)

Class B foam is used to extinguish Class B materials, which include gasoline, oil, and jet fuel.

Aqueous film forming foam (AFFF, or alcohol resistant AR-AFFF) is a highly effective foam used for fighting high-hazard flammable liquid fires. AFFF is usually created by combining foaming agents with fluorinated surfactants. Per- and polyfluoroalkyl substances (PFAS) are the active ingredient in these fluorinated surfactants.

When mixed with water and discharged, the foam forms an aqueous film that quickly cuts off the oxygen to the fire, cools it, extinguishes the fire, and prevents the fire from relighting. (Think fire triangle: oxygen, fuel, heat.)

Best practices for using Class B foam (AFFF)

When using Class B foam (AFFF), fire chiefs and firefighters should implement all of the best management practices in the following documents:

  • AFFF best management practices

    Best Practices for Using AFFF

    Updated June 2024

    A summary of state laws regarding PFAS-containing AFFF and the Key Points related to the selection, storage, testing, containment, treatment, and disposal of PFAS foams.

  • AFFF best management practices key points

    Best Practices for Using AFFF: Key Points

    Updated June 2024

    Strictly the Key Points related to the selection, storage, testing, containment, treatment, and disposal of PFAS foams.

  • Class B AFFF Best Practices Poster

    Poster: Use of Class B AFFF

    Best practices for Class B foam, which include when it should be used and clean-up procedures.

    This poster was distributed to all fire departments in the state of Michigan in 2019.

Michigan Firefighter Class B AFFF PFAS Training Video

Michigan Firefighter Class B AFFF PFAS Training

This is a video to train Michigan Firefighters on the proper use and handling of Class B AFFF containing PFAS.

AFFF collection and disposal program

Michigan was one of the first states in the country to launch a state-wide Class B AFFF Pickup and Disposal Program to protect firefighters, residents and remove AFFF from the environment. Through this collection and disposal program, Michigan had collected over 60,000 gallons of AFFF. 

As of October 2025, funding for the AFFF pickup and disposal program has been exhausted. However, EGLE is maintaining a waiting list in the event that additional funds become available. Please contact Steve Noble, EGLE Materials Management Division, at NobleS4@Michigan.gov or 517-449-6153 to be placed on this waiting list.

In the meantime, fire chiefs can dispose of their AFFF at a hazardous waste disposal facility or via a PFAS treatment system.

How to tell if firefighting foam contains PFAS

It may not be easy to tell if the AFFF you have contains PFAS.  These chemicals are not required to be reported on any safety data sheets (SDS), as they currently are not considered a hazardous substance.  PFAS may not be listed under any active ingredients list, either.  A good indicator that the foam contains PFAS is if it mentions fluorosurfactant, fluoroprotein, C6, or the use of "fluoro", however, not all fluorinated surfactants are made of PFAS.  The best thing to do is to note the brand and manufacturer of the foam and contact the manufacturer in writing to see if PFAS is used in its production and ask for the SDS.  Be sure to be clear that you mean the entire family of PFAS, not just the single compound PFOS, and be sure to review the SDS.

Following is an example of PFAS language from a Safety Data Sheet:

Product Name: Buckeye 3% Mil Spec AFFF

In Section I, Chemical Product and Company Identification, we find AFFF Concentrate, Aqueous Film Forming Foam.  This is our first clue that the product may contain PFAS.

AFFFSDSSectionI

In Section III, Composition/Information on Ingredients, we find "Proprietary mixture of Fluorosurfactants (bolded to identify key words) and hydrocarbon surfactants".  This AFFF contains PFAS. 

AFFFSDSSectionIII

Further, note the below statement does not mean it does not contain PFAS.  It means the product was manufactured with PFAS that did not contain PFOS. Also note, that PFAS is not mentioned anywhere else in the SDS.

AFFFSDSSectionIIIb

Fluorine-free AFFF

Now that we know what to look for, you can learn more information on PFAS-free material from the Interstate Chemicals Clearinghouse. You may also consult GreenScreen for Safer Chemicals. 

Also, be aware that performance and testing of the fluorine-free AFFF is still going on. Below are the current findings. 

What we know and don't know about fluorine-free AFFF

From the review of firefighting foam performance standards, current and upcoming regulations, identification of fluorine-free foams, other researchers working in this area, and literature, the following conclusions and actions have been identified:

  1. Three main information gaps need to be filled to characterize fluorine-free foams in order to promote them as safer alternatives to fluorinated foams:
    • Current performance data is uncertain and/or lacking.
    • The makeup of foams is incomplete as many ingredients are protected as confidential business information.  Many researchers and those in the firefighting foam industries have raised a concern about whether foams are truly fluorine-free or not.
    • The ecotoxicity and impacts on human health of most fluorine-free foams and their ingredients have not been characterized or assessed.
  2. Organizations are developing fluorine-free foams, characterizing them, and performing alternatives assessments.  Washington is the first U.S. state to ban the sale of fluorinated foams.
  3. There is no regulation preventing the use of fluorine-free foams by non-military users, including firefighting training centers, chemical manufacturers, oil refineries, and others. 

For additional information on AFFF please contact the Environment, Great Lakes and Energy (EGLE) Department's Environmental Assistance Center at 1-800-662-9278