Application Range
Standard Measuring Range: 0.05 to 0.7 ppm
Number of Strokes n: 10
Time for Measurement: approx. 3 min
Standard Deviation: ± 10 to 15 %
Color Change: pale blue -> white
Ambient Operating Conditions
Temperature: 0 to 40 °C
Absolute Humidity: 2 to 30 mg H2O / L
Reaction Principle
O3 + indigo -> isatine
Cross Sensitivity
No interference by:
1 ppm sulfur dioxide
1 ppm chlorine
1 ppm nitrogen dioxide
Higher concentrations of chlorine and nitrogen dioxide discolor the indicating layer a diffuse white to pale grey.
Extension of the Measuring Range
Using n = 5, multiply the reading by 2; the measuring range will be 0.1 to 1.4 ppm. Using n = 100, divide the reading by 10; the range of measurement is 0.005 to 0.07 ppm