Unlike aspirating nozzles, compressed air foam systems convert ninety percent of the water to foam. Systems of 40 units provide instant knockdown from 30 metres with 150 litres of water as foam. Water conservation is a key feature. A limited water supply cannot only be expanded, but because of the expansion, the water also becomes more effective. There are applications for both the firefighter who may have to drive to a distant water source, and the rural home owner who may have a finite water supply.
Hoses filled with foam are also lighter and more manoeuvrable .
The clinging, wetting, and reflecting properties of Class A foam make exposure protection perhaps its most effective application. Compressed air provides the discharge distance to reach, and the agitation to cling to walls, eaves, roofs, and trees. Small, portable pumping systems can give the home owner a method of on site structure protection. Utilisation of the compressed air foam system on test structure fires has duplicated this feat. Conclusion Utilisation of water for fire suppression has remained unchanged over the centuries, with few exceptions.