Application Range
Standard Measuring Range: 0.005 to 0.05 ppm
Discoloration compared to color standard.
Number of Strokes n: 200
Time for Measurement: approx. 5 min
Standard Deviation: ± 30%
Color Change: white-› blue
Ambient Operating Conditions
Temperature: 15 to 30°C
Absolute Humidity: 3 to 15 mg H2O / L
Reaction Principle
Dimethyl sulphate + 4-(4-Nitrobenzyl)-pyridine -> colorless alkylation product
colorless alkylation product -> blue reaction product
Cross Sensitivity
Phosgene and chloroformates cause a yellow discoloration of the indicating layer, and it is impossible to perform a dimethyl sulphate measurement. Alcohols, ketones, aromatics and petroleum hydrocarbons in the TLV range do not affect the indication