Compaction 04 : An increase in the density of the powder in a dry chemical or dry powder fire extinguisher caused by vibration or impact that may prevent the extinguisher from discharging properly
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}