AFFF

Fire Retardant Foam, or fire suppression foam, is a foam used for fire suppression. Its role is to cool down the fire and to coat the fuel, preventing its contact with oxygen, resulting in suppression of the combustion. The surfactants used have to produce foam in concentration of less than 1%.Other components of fire retardant foams are organic solvents (eg. trimethyltrimethylene glycol and hexylene glycol. Foam stabilizers are used as well, eg. lauryl alcohol. Other chemicals are used as well, eg. corrosion inhibitors.Low-expansion foams are foams with expansion rate lower than 20 times. Foams with expansion ratio between 20-200 are medium expansion. The low-expansion foams, eg. AFFF, are low-viscosity, mobile, able to quickly provide coverage of large areas.
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