The fire service is often notoriously slow to adopt changes, but 15 years after Class A foam started to appear as a factory option on new fire apparatus, the majority of new pumpers being delivered today are equipped with foam proportioners and Class A foam concentrate tanks.
All the major pump manufacturers offer Class A foam proportioners – Darley, Hale and Waterous – and all three also offer compressed air foam systems (CAFS) as well. Pierce, the nation’s largest apparatus manufacturer, has developed its own proprietary system for both nozzle aspirated foam, the Husky, and CAFS, Hercules, proportioners.
Nozzle-aspirated foam systems double the fire suppression effectiveness of plain water. The really dramatic difference comes with a CAF system which breaks water into such tiny, uniform bubbles that heat absorption capacity is multiplied 4 to 5 times, resulting in remarkably fast fire knockdown times.
Several large cities have led the way in adopting Class A foam. All 58 engine companies in Phoenix, Ariz., are CAFS-equipped. All 220 engine companies of the Los Angeles County Fire Department have had Class A foam proportioners for the past 10 years, and will get 96 new Class A foam-equipped engines under a contract with KME.
Last year San Diego, Calif., started taking delivery of 50 new pumpers, all with Class A foam, and in February, Montgomery County, Md., awarded a contract to Elite Fire Apparatus for 37 new engines with CAF systems. Rosenbauer, which estimates that 80 percent of the pumpers it is building today will have Class A systems, delivered 33 engines last fall to the island of Jamaica, all with Class A foam systems.
According to Pierce, 36 percent of its pumpers delivered with Class A foam systems in 2006 were ordered with the Hercules Compressed Air Foam units, and CAF systems accounted for 15 percent of all pumper sales. Just five years ago, Pierce said that CAF systems being delivered were less than half than number.
The Fire Apparatus magazine report by David Smith on the 2007 Southeastern Seminar on CAFS illustrates the rapid growth of interest in CAFS in the last five years. More information can be found on the Web at www.cafsinfo.com and at www.compressedairfoam.com.