Foam Generators (FCH *-250 are designed to expand foam solution into millions of tiny bubbles in which the foam solution is expanded in volume to a range of 200:1 to 450:1 approximately depending on the generator selected, solution flow rate, foam concentrate and the operating pressure.
The extinguishing mechanisms of FIRECHEM HiEx Foam Generator (FCH* -250) involve a combination of the following:
- Free air movement necessary for continued combustion is reduced.
- Water content of the foam being converted to steam dilutes the oxygen concentration to a level below that necessary to support combustion.
- Cooling to a temperature below the combustion point or auto- ignition temperature of Class A or Class B fuels occurs as water is converted to steam.
- Reduced surface tension of the foam solution draining from expanded foam penetrates into Class A materials extinguishing deep seated fires.
- Insulating and heat reflective properties of the foam blanket provide a heat shield preventing fire spread extinguishing deep seated fires.