An environmentally low-impact alternative to traditional aqueous film-forming foams (AFFF) for sprayable fire retardants offered by Paradise Environmental Group (Paradise, PA) was tested by the U.S. Army Combat Capabilities Development Command Chemical Biological Center (Aberdeen Proving Ground, MD). Liquid solutions of this material, known as BlazeCheck, are easily mixed in either fresh or salt water. Their method of action is assumed to be an emulsification of the fuel volume, which decreases the vapor pressure required to ignite and sustain combustion. This is a different mechanism of action as compared to the AFFF, which blanket the fuel surface with a film and cut off the oxygen supply. AFFF will no longer be in use for Department of Defense (DoD) land-based applications starting in FY24 due to the PFAS content in AFFF.

Testing was divided into laboratory and full-scale performance testing. The objectives of the laboratory testing were to determine the corrosivity of the BlazeCheck solution, the presence of any per- and polyfluoroalkyl substance (PFAS)-containing compounds, and the general material properties. The objective of the performance testing was to determine the ability of the BlazeCheck solution to suppress the flame associated with liquid fuel fires, metal powder fires, and pyrotechnic fires. Liquid solutions of this material, known as BlazeCheck, are easily mixed in either fresh or salt water. Their method of action is assumed to be an emulsification of the fuel volume, which decreases the vapor pressure required to ignite and sustain combustion. This is a different mechanism of action as compared to the AFFF, which blanket the fuel surface with a film and cut off the oxygen supply.

Positive indicators for BlazeCheck include the noncorrosive nature of the solution (in fresh or salt water), the lack of any PFAS detected in the material, the nontoxic nature of the material, the relatively cheap cost of the solution, and the product’s ability to extinguish class A and B fires relatively quickly in small fuel pools (diesel and gasoline) and some apparent effectiveness in extinguishing class D metal particle and pyrotechnic fires.

Negative indicators for BlazeCheck include the necessity to add significant amounts of the solution and the time involved to extinguish the flames for large fuel pool class B fires, as was demonstrated in the 28 ft² pan test. Also, for a large fuel pool, even if the top layers are passivated, the fire can easily restart if the fuel below that level is disturbed and brought to the surface by mechanical action. This effect was demonstrated in the large fuel pool fire burnback tests.

BlazeCheck was found to be readily miscible in water and to have a slightly basic pH and a kinematic viscosity similar to coconut oil. It was found to be noncorrosive against metal coupons in sea water solution, and no trace of PFAS was found after analysis with mass spectrometry. In summary, BlazeCheck solution appears to be an effective and safe general-purpose fire retardant for specific firefighting applications.