某企业发生了一起因防爆开关内部放电引燃可燃气体，造成数人伤亡的爆炸事件。　　对该防爆开关现场检查发现，开关内部固定在胶木片之间的一个电触头与连接导线整体脱离固定件，与接地良好的金属外壳接触发生放电。线端放电痕迹清晰，铸铝外壳放电部位被击穿几个直径在８ｍｍ A business explosion occurred due to an internal discharge of combustible gas discharge, resulting in several casualties of the explosion. The on-site examination of the explosion-proof switch found that the switch is fixed within the bakelite within a piece of electrical contacts and the overall separation of the connecting wire from the fixture, and a good grounding contact with the metal shell discharge. Line discharge marks clear, cast aluminum shell discharge parts were punctured several diameter 8mm