During the WP19-5324 program, the commercially available Per- and polyfluoroalkyl substances (PFAS)-free foams and agents were identified and documented in a spread sheet with links to Material Safety Data Sheets/Safety Data Sheets, approvals/listings, performance test data and end user testimonials. During Task 3 of the program, over 20 commercially available products were tested against the 28 ft2 Military Specification (MIL-SPEC) pan fire tests using two fuels (the legacy gasoline and Jet A). During Task 5, a baseline C6 MILSPEC aqueous film forming foam (AFFF) and the five top fluorine free products were then tested against a 400ft2 pan fire to assess scalability and to provide an initial assessment of how foam quality/aspiration effects the firefighting capabilities of these products. Both series demonstrated the potential of using these products in Department of Defense (DoD) applications with the understanding that final validation tests would be required.

During this follow-on effort, the capabilities of the top fluorine free products will be assessed and validated against the test configurations used to assess the capabilities of AFFF 30 to 40 years ago. These include obstructed running fuel fire scenarios (referred to as debris pile fire scenarios) that include both an obstructed three-dimensional (3D) component and a growing, uncontained spill/pool fire.

Technical Approach

In the late ‘70s and early ‘80s, Jensen Hughes/the U.S. Naval Research Laboratory/Naval Air Warfare Center Weapons Division (NAWCWD) personnel developed a debris pile fire test scenario to assess firefighting equipment and agents, and to develop firefighting doctrine and training for aircraft carrier flight deck crash scenarios. A majority of this research and doctrine has been incorporated into the Naval Air Training and Operating Procedures Standardization manual.

The debris pile fire scenario was designed to represent the Maximum Credible Event (MCE) that could occur on the flight deck of an aircraft carrier during peacetime operations (i.e., an aircraft crash with all ship’s systems and crew functional). The initial debris pile fire test scenario consisted of a 40 gallon per minute running fuel fire that flowed down numerous steel trays that served to heat the fuel and to obstruct the fire as it flowed into a large pile of broken cinderblocks. Many of the tests were conducted with instrumented mock-ordnance located in the debris. Over the years, the debris pile fire scenario has been conducted using a range of fuels and has been modified during numerous test programs to simulate obstructed, 3D running fuel fires for a range of scenarios and applications including evaluations of fixed fire suppression systems and manual firefighting equipment and techniques (both handlines and turrets/monitors).

During this project, the top PFAS-free products will be assessed against the legacy debris pile fire on the mini-deck at China Lake Warfare Center, using the same exact configuration and location where all the legacy AFFF testing was conducted. As with the previous studies (i.e., WP19-5324), the results will be compared to the performance of a C6, AFFF currently on the Qualified Products List.

The mini-deck is an 80ft by 80ft concrete pad constructed of high temperature concrete. The deck construction allows the fuel to be dumped or flowed directly onto the concrete surface representative of an actual crash type scenario. The deck is equipped with an effluent drainage and waste collection system for waste disposal. The use of the mini-deck provides the ability to spill the fuel directly onto the concrete surface without the need for any type of containment which is representative of an actual crash type scenario on the flight deck of an aircraft carrier or on the tarmac of military airfield.

This project consists of two series of representative scale tests as well as detailed decomposition product assessments. A detailed decomposition product assessment will be initially performed in the laboratory at NAWCWD-China Lake. The second assessment will consist of collecting samples from representative scale/scenario tests to correlate with the laboratory scale results.


The project should provide the required performance validation data against a simulated MCE that has been used to assess/challenge the legacy AFFF products for almost 50 years. The project also offers the opportunity to adjust (i.e., tweak) the hardware, techniques and procedures developed for AFFF with the intent to maximize the capabilities of these new PFAS-free products in DoD/Aviation Rescue Firefighting applications. The project will also provide an understanding of foam pyrolysis products generated during actual/representative events.


DISTRIBUTION STATEMENT A. Approved for public release: distribution unlimited.


  • PFAS - AFFF Alternatives,

  • AFFF,