Water-Type Fire Extinguishers
Water-type fire extinguishers (contain waterbased agents, such as water, AFFF (aqueous film-forming foam), FFFP (filmforming fluoroprotein foam), antifreeze, and loaded stream. AFFF and FFFP fire extinguishers are rated for use on both Class A and Class B fires. They are not for use in freezing temperatures. An advantage of this type of extinguisher when used on Class B flammable liquid fires of appreciable depth is the ability of the agent to float on and secure the liquid surface, which helps to prevent re-ignition.
A colorless, odorless, electrically non-conductive inert gas that is a suitable medium for extinguishing Class B and Class C fires. Liquid carbon dioxide forms dry ice when released directly into the atmosphere. Since the agent is dispensed as a gas/snow cloud, it has a relatively short range of 3ft. to 8ft.
These agents are designed for extinguishment of Class A and Class B fires. They are non-conductors and are approved for use on energized electrical Class C fires. Dry chemical extinguishers have a discharge stream that ranges from 10ft to 30ft depending on extinguisher size. Dry Chemical extinguishers come in the form of stored pressure canisters, cartridge operated canisters or various wheeled carts.
Solid materials in powder or granular form designed to extinguish Class D combustible metal fires by crusting, smothering, or heattransferring means. Chemical reaction between burning metals and extinguishing agents (including water) can range from explosive to inconsequential, depending in part on the type, form, and quantity of the metal involved.
Halogenated Agents (Clean Agents)
Halocarbon agents are listed for Class A, B and Class C fires, which make them quite suitable for use on fires in electronic equipment. When discharged, the agent is in a combined form of a gas/mist, which is about twice the range of carbon dioxide. Strong air currents may make the extinguishing difficult by causing rapid dispersal of the agent.