Firefighting foam has long been used as an alternative to water, giving firefighters the ability to douse specific types of fire. There are several types of firefighting foam: regular protein foam, fluoroprotein foam, film-forming fluoroprotein foam (FFFP), alcohol resistant (FFFP), aqueous film-forming foam (AFFF), alcohol-resistant (AFFF), and Class A foam, plus its related compressed air foam systems (CAFS). Firefighters use AFFF to help extinguish difficult-to-fight fires, particularly fires that involve petroleum or other flammable liquids ‚ known as Class B fires. Of note is the concern about firefighters’ exposure to toxic chemicals from firefighting foam. Specifically, some AFFF formulations contain a class of chemicals known as perfluorochemicals (PFCs), a group of toxic chemicals that includes PFOA and PFOS and other per- and polyfluoroalkyl substances (PFAS). These so-called “forever chemicals” may take hundreds of years to break down in the environment, contaminating groundwater and potentially causing health problems. PFOS were used in the manufacturing of firefighting foam through the early-2000s, although some foam that contains it may still be in service. U.S.-based manufacturers have since used other short-chain PFAS in an effort to be safer.