任务特性................................................................................................4-1 准备...............................................................................................................4-3 事故优先级....................................................................................................4-4 现场安全和保障................................................................................................4-6 净化.................................................................................................................4-8 污染控制.......................................................................................................4-9 环境考虑.......................................................................................................4-9 密闭空间作业....................................................................................................4-10 终止事故....................................................................................................4-11