Some of the firefighting foams known as aqueous film-forming foams (AFFF), including alcohol-resistant aqueous film-forming foams (AR-AFFF), contain per- and polyfluoroalkyl substances (PFAS), sometimes referred to as “forever chemicals.” Fluorine is the key ingredient in AFFF that is the source of PFAS. Firefighting foams that do not contain fluorine do not contain PFAS. PFAS can remain in the environment indefinitely, potentially causing health effects. The environmental and health concerns with PFAS have led to an increase in regulation at both the state and federal levels. As a result, PFAS are being phased out in the U.S. and across the globe, and research on fluorine-free alternatives has surged.
For decades, AFFF has been considered the best option for extinguishing fuel-based fires (Class B flammable liquid fires), and these foams are widely used in both the power generation and oil and gas industries. In AFFF, PFAS act as an effective surfactant that helps spread the foam. These foams are a source of PFAS contamination because of their deployment during fires, fire system testing and firefighter training. AFFF is commonly used at member power stations in foam water sprinkler systems, in tank foam extinguishing systems or for manual firefighting where oil and fuel oil hazards are present. Member utilities that have fire training facilities may have used AFFF during training exercises.
Manufacturers have been working on AFFF replacements for years, and there are many foam products currently available that claim to be made without fluorine (that is, without PFAS). But testing on many of these foams has shown that their performance fluctuates based on such variables as the delivery equipment or system, the fuel that is burning, the foam aspiration level, firefighting tactics and application techniques. Unlike with AFFF, the effectiveness of fluorine-free foams varies widely. The currently available fluorine-free foams are essentially new products with varying properties. As a result, the delivery systems will be different for each of these dissimilar products and will most likely require full replacement of the mechanical portion of an existing foam delivery system.