Foam concentrate types and how each one extinguishes, the PFAS transition reshaping AFFF specification, foam proportioning methods, and where foam-water systems are actually applied.
Foam suppresses flammable-liquid fires by a mechanism ordinary water sprinklers can't replicate — smothering fuel vapor under a floating blanket rather than just cooling the fuel. This module works through the three foam concentrate families (protein, AFFF, and alcohol-resistant AFFF), why AFFF's film-forming property made it the dominant hydrocarbon-fire foam for decades, and the PFAS-driven transition toward fluorine-free foam that is actively reshaping specification today.
It closes with the proportioning methods that actually meter concentrate into the water stream — bladder tank, in-line eductor, and balanced pressure — and the applications (flammable liquid storage, aircraft hangars, parking garages) where foam-water sprinkler and deluge systems are the correct design choice over a conventional water-only system.