Application Range
Standard Measuring Range: 20 to 300 ppm
Number of Strokes n: 1
Time for Measurement: approx. 20 s
Standard Deviation: ± 10 to 15 %
Color Change: greenish blue -> yellow
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 yellowish grey.