Sulphur dioxide SO2 No.5EC

ppm

5EC2 5 40302010

SO2 ＋ I2 ＋ H2O → 2HI ＋ H2SO4

Reaction principle

Possible coexisting substances and their interferences

Nitrogen dioxide −（unclear 　 demarcation） Hydrogen sulphide ≧ 1/10 ＋ White（unclear demarcation）

Substance Concentration Interference Changes colour by itself to

Permeation tube methodCalibration gas generation

0.4 ppm（1 pump stroke）Purple → WhiteTemperature 0 to 40 ℃ (32 to 104 ℉) correction usedRelative humidity 0 to 90 % correction not used10 %（for 2 to 10 ppm）, 5 %（for 10 to 40 ppm）10 tubes for 10 tests36 months

Detecting limit :Colour change :Operating conditions :

Relative standard deviation :Tube quantity and number of tests per box :Shelf life :

Performance

2 to 40 ppm 1（50mL） 1 45 sec

Measuring rangeNumber of pump strokesCorrection factorSampling time

Scale