Ammonium Sulfate 2 : A compound (N2H8SO4) that has crystals ranging from brownish-gray to white, depending on degree of purity, and low toxicity; it is used as an extinguishing agent, particularly for wildland fires
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}