Multipurpose Dry Chemical 2 : An extinguishing agent, usually with a base of monoammonium phosphate, that is effective on fires in ordinary combustibles, flammable liquids, and electrical equipment
Ralph W. Burklin & Robert G. Purington, Fire Terms: A Guide to Their Meaning and Use, National Protection Association, Boston, MA 1980 USA. (Guide: Meaning and Use, Nat Prot Association Fr Srvc - Amer) {457}