Ignitible Mixture 1 : (1) A vapor-air or dust-air mixture that can be ignited by a static spark. (2) A mixture that is capable of the propagation of flame away from the source of ignition when ignited
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}