现场防护时口笛是在何条件下使用？
["4\u81f35\u4eba\uff08\u542b5\u4eba\uff09\u4f5c\u4e1a\u6216\u8005\u73b0\u573a\u9632\u62a4\u8303\u56f4\u57285\u7c73\u4ee5\u5916\u300120\u7c73\u4ee5\u5185\u65f6\u4f7f\u7528."]
现场防护时口笛是在何条件下使用？
["4\u81f35\u4eba\uff08\u542b5\u4eba\uff09\u4f5c\u4e1a\u6216\u8005\u73b0\u573a\u9632\u62a4\u8303\u56f4\u57285\u7c73\u4ee5\u5916\u300120\u7c73\u4ee5\u5185\u65f6\u4f7f\u7528."]