| Benzene | C6H6 | NO.121S | |
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| Performance |
|
Measuring Range |
2 to 5 ppm |
5 to 120 ppm |
120 to 312 ppm |
|
Number of Pump Strokes |
4 |
2 |
1 |
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Correction Factor |
0.4 |
1 |
2.6 |
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Sampling Time |
2 minutes per pump stroke |
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Detecting Limit |
0.5 ppm (n=4) |
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Color Change |
White |
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Reaction Principle |
Benzene reduces iodine pentoxide to liberate iodine, C6H6 + I2O5 + H2S2O7 |
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| Coefficient of Variation | 20% (for 5 to 40 ppm), 15% (for 40 to 120 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 |
|
Hexane |
100 ppm |
No effect |
No discoloration |
|
Toluene |
200 ppm |
No effect |
No discoloration |
|
Xylene |
300 ppm |
No effect |
No discoloration |
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Aromatic hydrocarbons other than benzene are trapped in the brown layer in the pretreatment tube.If the pretreatment reagent is entirely consumed (whole brown layer turns to dark brown),a higher reading will be given. |
| Calibration gas generation | Diffusion tube method | |
| TLV-TWA | TLV-STEL | Explosive range |
| 0.5ppm | 2.5ppm | 1.3 to 7.1% |
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| Copyright(c) 2001 GASTEC CORPORATION. All rights reserved. |
Brownish gray
I2