Nitrogen oxides |
NO.10 |
| NO2, NO (Separete quantification) |  |
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Performance
| Name of Gas |
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| Measuring Range |
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| Number of Pump Strokes |
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| Correction Factor |
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| Detecting Limit |
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| Sampling Time | 1 minute per pump stroke | |||
| Colour Change | White → Yellowish orange | |||
| Reaction Principle | NO2 tube: NO2 + o-Tolidine Yellowish orange product NO tube: NO + Cr6+ + H2SO4 →NO2 NO2 + o-Tolidine Yellowish orange product |
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| Coefficient of Variation | NO2 tube: 10% (for 2.5 to 20 ppm), 5% (for 20 to 200 ppm) NO tube:10% (for 5 to 20 ppm), 5% (for 20 to 200 ppm) |
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| Shelf Life | 3 Years | |||
| Corrections for temperature & humidity | NO2 tube:Unnecessary
NO tube:Temperature correction is necessary |
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| Store the tubes at cool and dark place. | ||||
| Substance | Concentration | Interference | Change colour by itself to |
| Nitric Oxide | No | Red(entrance of the detecting layer) | |
| Hydrogen chloride | Unclear demarcation | No | |
| Ozone, Halogens, Chlorine dioxide |
1/5 | +20% | Yellowish orange |
| Sulphur dioxide | 50 ppm | Unclear demarcation | No |
Possible coexisting substances and their interferences (NOTE)
For the NO tube
For the NO tube
| Substance | Concentration | Interference | Change colour by itself to |
| Hydrogen chloride | No | No | |
| Ozone, Halogens, Chlorine dioxide | No | No | |
| Sulphur dioxide | No | No | |
| Nitrogen dioxide | No | No |
| Calibration gas generation | Permeation tube method |
| TLV-TWA | TLV-STEL | Explosive range |
| NO2: 3 ppm NO: 25 ppm |
NO2: 5 ppm | - |
