Application Range
Standard Measuring Range: 5 to 40 ppm
Number of Strokes (n): 15 to 2
Time for Measurement: max. 3 min
Standard Deviation: ±30%
Color Change: white -› red brown
Ambient Operating Conditions
Temperature: 0 to 40 °C
Absolute Humidity: max. 50 mg H2O / L
Reaction Principle
2 C6H6 + HCHO ä C6H5-CH2-C6H5 + H2O
C6H5-CH2-C6H5 + H2SO4 ä p-quinoid compound
Cross Sensitivity
Other aromatics (toluene, xylene) are retained in the pre-layer
causing a reddish brown discoloration. If the toluene or xylene
concentrations are too high the entire pre-layer up to the indicating
layer is discolored making a benzene measurement impossible. Petroleum
hydrocarbons, alcohols and esters do not affect the
indication.