Sulphur dioxide |
NO.5LC |
| SO2 |  |
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Performance
| Measuring Range |
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| Number of Pump Strokes |
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| Correction Factor |
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| Sampling Time | 2 minutes per pump stroke | |||
| Detecting Limit | 0.02 ppm (n=4) | |||
| Colour Change | Bluish purple → White | |||
| Reaction Principle | SO2 +I2 +2H2O H2SO4 + 2HCl | |||
| Coefficient of Variation | 10% (for 0.25 to 2 ppm), 5% (for 2 to 10 ppm) | |||
| Shelf Life | 3 Years | |||
| Corrections for temperature & humidity | Temperature correction is necessary | |||
| Store the tubes at cool and dark place. | ||||
Possible coexisting substances and their interferences (NOTE)
| Substance | Concentration | Interference | Change colour by itself to |
| Nitrogen dioxide |  (Unclear demarcation) |
Brown (approx.1mm long from the inlet) | |
| Hydrogen sulphide | 1/10 | + | White |
| Calibration gas generation | Permeation tube method |
| TLV-TWA | TLV-STEL | Explosive range |
| 2 ppm | 5 ppm | - |
