High expansion foam is used where total and full flooding of the area is required. By total flooding, the fire area, the oxygen required for the fire to burn is reduced and this allows the foam to be released slowly and continuously and there is better penetration of the foal solution. It can be used for air aspirated and non-air aspirated systems. The foam is able to cover a larger area and retains water for wetting properties.
High expansion foam is utilized in LNG fires and other types of very fast-spreading Class A fires. It can be used in aircraft hangars, warehouses, buildings, process areas, gasoline handling areas, and so on. Typically, expansion is 1:200 times. Low expansion foam has a lower spread and the foam has a higher weight. The expansion ratio is 1: 20 times. The foam is used in gas fires and is resistant to heat and flames and seals flaming gas so that the gas pressure does not force the foam out. The foam fights fire with film formation, separation, and cooling. It can be used through a sprinkler head system and for manual application.