Sulphur Dioxide 20/a, 20 - 200 PPM, Part # CH24201, 10 Tests 

Application Range

Standard Measuring Range: 20 to 200 ppm

Number of Strokes n: 10

Time for Measurement: approx. 3 min

Standard Deviation: ± 10 to 15 %

Color Change: brown yellow š white

Ambient Operating Conditions

Temperature: 0 to 40 °C

Absolute Humidity: < 30 mg H2O / L

Reaction Principle

SO2 + I2 + 2 H2O š H2SO4 + 2 HI

Cross Sensitivity

Hydrogen sulfide is indicated, with the same sensitivity. It is impossible to measure sulfur dioxide in the presence of hydrogen sulfide. Nitrogen dioxide will shorten the reading.

Extension of the Measuring Range

Using n = 1+3 desorption strokes, multiply the reading by 10; the range of measurement is 200 - 2,000 ppm. The desorption strokes are to be taken in clean air (i.e. free of sulfur dioxide) immediately following the single pump stroke.