Combining　with　the　characteristics　of　effervescent　atomization　and　knapsack　water　mist　fire　fighting　equipment,　a　water　mist　fire　extinguishing　equipment　was　developed.　A　series　of　wood　crib　fire　suppression　experiments　were　performed　using　the　equipment.　According　to　the　process　of　putting　out,　the　dominant　mechanism　of　extinguishment　with　water　mist　was　analyzed.　A　wood　crib　fire　under　0.6A　can　be　put　out　in　150　seconds.　For　0.8A　wood　crib　fire,　it　cannot　succeed　by　effervescent　atomization　water　mist　equipment.