A.5MPa B.5.5MPa C.6MPa D.5.5±0.5MPa
A.氧含量為19.5%~23.5% B.氧含量小于19.5%或大于23.5% C.可燃性氣體、蒸氣濃度大于爆炸下限(LEL)的10% D.有毒有害氣體、蒸氣濃度大于GBZ2.1規(guī)定的限值
A.1mg/m3,5mg/m3 B.2mg/m3,8mg/m3 C.3mg/m3,10mg/m3 D.4mg/m3,12mg/m3