| Hydrogen sulfide | H2S | NO.4M |
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| Performance |
|
Measuring Range |
12.5 to 25 ppm |
25 to 250 ppm |
250 to 500 ppm |
|
Number of Pump Strokes |
2 |
1 |
1/2 |
|
Correction Factor |
1/2 |
1 |
2 |
|
Sampling Time |
30 seconds per pump stroke |
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|
Detecting Limit |
2.5 ppm (n=2) |
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|
Color Change |
White |
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|
Reaction Principle |
Hydrogen sulfide reacts with lead acetate |
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| Coefficient of Variation | 5% (for 25 to 250 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 color by itself |
|
Nitrogen dioxide |
1/4 timer |
Minus error |
No discoloration |
|
Sulfur dioxide |
1 time |
Plus error |
No discoloration |
|
Mercaptans |
- |
No effect |
No discoloration |
| Calibration gas generation | Permeation tube method | |
| TLV-TWA | TLV-STEL | Explosive range |
| 10ppm | 15ppm | 4.0 to 44% |
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| Copyright(c) 2001 GASTEC CORPORATION. All rights reserved. |
Brown