Hydrogen sulphide |
NO.4LK |
| H2S |  |
 |
Performance
| Measuring Range |
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| Number of Pump Strokes |
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| Correction Factor |
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| Sampling Time | 1 minute per pump stroke | |||
| Detecting Limit | 0.25 ppm (n=2) | |||
| Colour Change | White → Brown | |||
| Reaction Principle | H2S + Pb(CH3COO)2 → PbS + 2CH3COOH | |||
| Coefficient of Variation | 10% (for 2 to 6 ppm), 5% (for 6 to 20 ppm) | |||
| Shelf Life | 3 Years | |||
| Corrections for temperature & humidity | Unnecessary | |||
| Store the tubes at cool and dark place. | ||||
Possible coexisting substances and their interferences (NOTE)
| Substance | Concentration | Interference | Change colour by itself to |
| Mercaptans | No | No | |
| sulphur dioxide | 1/2 | + | No |
| Nitrogen dioxide | 1/4 |  |
No |
| Ozone | 10 ppm | Bleaching | No |
| Calibration gas generation | Permeation tube method |
| TLV-TWA | TLV-STEL | Explosive range |
| 1 ppm | 5 ppm | 4.0 to 44% |
