Hydrogen sulphide |
NO.4HP |
| H2S |  |
 |
Performance
| Measuring Range |
|
|||
| Number of Pump Strokes |
| |||
| Correction Factor |
| |||
| Sampling Time | 3 minutes per pump stroke | |||
| Detecting Limit | 0.1% (n=2) | |||
| Colour Change | Pale Blue → Blackish Brown | |||
| Reaction Principle | H2S + CuSO4 → CuS + H2SO4 | |||
| Coefficient of Variation | 10% (for 0.5 to 3 %), 5% (for 3 to 10 %) | |||
| 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 |
| Ammonia | Two layers (Dark brown & dark blue) |
Dark blue | |
| sulphur dioxide | 2.5% |  |
No |
| Mercaptans | 5 % | + | No |
| Calibration gas generation | High pressure gas cylinder method |
| TLV-TWA | TLV-STEL | Explosive range |
| 1 ppm | 5 ppm | 4.0 to 44% |
