GAS81D Acetic Acid Gastec Passive Sampling Dosi Tubes (Time Weighted Average Detector Tubes)
The Dosi-Tube System allows an operator to evaluate the level of gas a worker is exposed to over a time period such as a working shift.
The Dosi-Tube is easily clipped into the Dosi-tube holder (GAS710) which is worn on a garment of clothing.
Measuring Range |
0.5 to 100 ppm |
Sampling Hours |
1 to 10 hours |
Detecting Limit |
0.2 ppm (10 hours) |
Colour Change |
Purple Yellow |
Reaction Principle |
Acetic acid neutralizes alkali to discolour the indicator to yellow. |
Coefficient of Variation |
5% (for 5 to 20 ppm∙hr), 10% (for 20 to 100 ppm∙hr) |
Shelf Life |
Up to 3 years from point of manufacture |
Corrections for
temperature & humidity |
Temperature correction is necessary |
Store the tubes at cool and dark place. |
Possible coexisting substances and their interferences |
|
Substance |
Interference |
Change colour by itself |
Hydrogen Chloride, Nitric Acid |
Plus error |
Produce yellow stain |
Chlorine, Nitrogen Dioxide |
Plus error |
Produce yellow stain |
Hydrogen Cyanide, Sulphur Dioxide |
Plus error |
Produce yellow stain |
Other substance measurable with this detector tube |
Substance |
Correction |
Sampling Hours |
Measuring range |
Formic Acid |
Factor: 1.1 |
1 to 10 |
0.55 to 110 ppm |
Acetic Anhydride |
Factor: 0.6 |
1 to 10 |
0.3 to 60 ppm |
Calibration gas generation |
Diffusion tube method |