Different fuel sources require different firefighting foam solutions for fire protection. Specifically, the fuel source can be classified as either a polar liquid (alcohol) or a nonpolar liquid (oil/hydrocarbon). While all Class B foams will work on nonpolar liquids, only a foam labeled as alcohol resistant (AR) will work on polar solvents. If a foam is designed for only nonpolar liquids, it will not hold up on polar solvents, breaking down and exposing the fuel to the ignition source too quickly.
Dyne Fire Protection Labs offers two types of tests to determine if a firefighting foam is alcohol resistant:
- The Acetone Stability Test will determine how well the foam will hold up on acetone over time. This test is not a fire test as no ignition takes place.
- The Polar Burn Back Test will determine how long the foam will hold up on isopropyl alcohol (IPA) over time. This is a small scale fire test as the fuel is ignited during the test. The heat and solvent in this test create a different scenario from that of the Acetone Stability Test.
These tests are important because the foam must last long enough to keep a possible fire from reigniting an area that was once extinguished.
These tests are currently only required for alcohol resistant protein-based foams tested to IMO 1312. They can be done on any other foam upon request.