For primary screening of flue exhaust gas Measurement gas name 1(m): Sulfur dioxide;5M Sulfur dioxide detection tube Measurement range: 20-3600pp Measurement gas name 2(m): Sulfur dioxide;5L Sulfur dioxide detection tube Measurement range: 1.25-200pp Measurement gas name 3(m):氮氧化氮; 11HA氮检测试管测量范围:50-2500pp 测量气体名称4(M):氮氧化物; 11S氮氧化物检测试管测量范围:5-625pp