High-Pressure Fog : A small-capacity spray developed at high pressures and discharged through 1/2, 3/4, or 1 in. hose, usually with a pistol grip nozzle
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}