Xylene C H（CH ） 6 4 3 2 No.
123
n=1
ppm
Scale
123
150
200
250
100
20
50
Performance The minimum scale value (10ppm) is not printed on the tube, but only the scale line is printed.
Measuring range 5 to 10 ppm （10）to 250 ppm 250 to 625 ppm
Number of pump strokes 2（200 mL） 1（100 mL） 1/2（50 mL）
Correction factor 1/2 1 2.5
Sampling time 3 min 1.5 min 1 min
Detecting limit : 1 ppm（2 pump strokes）
Colour change : White → Brown
Operating conditions : Temperature 0 to 40 ℃ (32 to 104 ℉) correction not used
Relative humidity 0 to 90 % correction not used
Relative standard deviation : 10 %（for 10 to 50 ppm）, 5 %（for 50 to 250 ppm）
Tube quantity and number of tests per box : 10 tubes for 10 tests
Shelf life : 36 months
Reaction principle
C6H4（CH3）2 ＋ I2O5 ＋ H2SO4 → I2
Possible coexisting substances and their interferences
Substance Concentration Interference Changes colour by itself to
Toluene ≧ 1/5 ＋ Brown
Acetylene, Hexane ≧ 2000 ppm ＋（Two layers）
Pale brown（Whole layer）
Carbon monoxide ≧ 1000 ppm ＋（Two layers）
Benzene ≧ 1/5 ＋ Pale yellow
Other substance measurable with this detector tube
Substance Correction No. of pump strokes Measuring range
Trimethylbenzene by scale 2 10 to 300 ppm
Calibration gas generation
Diffusion tube method
