Non-PFAS Fire Fighting Foam
The FAA ended 2024 by issuing a National Part 139 CertAlert (No. 24-11) concerning Output Based Testing After Completion of Fluorine Free Foam (F3) Transition. The Alert specifies the types of testing that must be done on ARFF vehicles following the transition by the Airport from AFFF containing PFAS to a recently-approved F3 liquid concentrate, based on Military Specification MIL-PRF-32725.
Pursuant to the FAA Reauthorization Act of 2018 (Public Law 115-254 – October 5, 2018), the FAA was given three years to develop and approve a new type of fire fighting foam that does not contain PFAS chemicals. While that goal was not met, by 2024 the FAA had approved an alternative to AFFF known as “F3”. However, just switching from AFFF to F3 was not a complete answer. The fire fighting vehicles used to transport and transmit F3 had to be shown to be “…operationally capable of performing their functions required by the regulation during all air carrier operations.”
In practice this means that all firefighting systems used for ARFF purposes must be tested and certified as being in “optimal condition for emergency purposes.” This is a special concern as due to the different viscosities of F3 in relation to both AFFF and other F3 products, “flow rates after transitioning to F3 have been below tolerance.”
Once an airport ARFF index vehicle has been transitioned from AFFF to F3, the vehicle must be both output and input tested. The first step is input testing to identify and correct any issues with the ARFF vehicles. The Airports must confirm:
- Discharge flow rates are within range and stable;
- There is not bad sealing in the metering devices causing flow through the proportioning system when not discharging;
- Orifices only open for their corresponding and proper discharge;
- Pump pressure is in proper operating range; and
- Manual foam metering valve and/or bypass is disabled.
After that output testing is required, utilizing the roof and bumper turrets only, to ensure both electronic and mechanical foam proportioning systems are functioning property. The output-based test for each turret must be within 2.8% and 3.5% for turrets.
Once the output testing is completed, another input test is required to be used as the reference value moving forward for all input-based tests.
Finally, all certificated Part 139 airports shall notify their Airport Certification Safety Inspector once the transition to F3 and the testing are complete.
For more information please contact Daniel Markind, Marty Judge, or any member of Flaster Greenberg’s PFAS Task Force or Airport Group.
