Methylene chloride |
NO.138 |
| CH2Cl2 |  |
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Performance
| Measuring Range |
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| Number of Pump Strokes |
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| Correction Factor |
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| Sampling Time | 3 minutes per pump stroke | ||
| Detecting Limit | 10 ppm (n=2) | ||
| Colour Change | White → Pale Pink | ||
| Reaction Principle | CH2:Cl2 + CrO3 + H2S2O7 → Cl2 Cl2+ 3,3,5,5-Tetramethylbenzidine → Holoquinone |
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| Coefficient of Variation | 15% (for 50 to 100 ppm), 10% (for 100 to 500 ppm) | ||
| Shelf Life | 3 Years | ||
| Corrections for temperature & humidity | Temperature correction is necessary | ||
| Store the tubes at cool and dark place. | |||
Possible coexisting substances and their interferences (NOTE)
| Substance | Concentration | Interference | Change colour by itself to |
| Cl2, Br2, I2 | + | Pale pink | |
| Unsaturated halogenated HCs | + | Pale pink | |
| Saturated halogenated HCs | + | Pale pink |
Other substance measurable with this detector tube
| Substance | Correction Factor | No. of pump strokes | Measuring Range |
| Ethyl Chloride | 0.3 | 1 | 15 to 150 ppm |
| Calibration gas generation | Diffusion tube method |
| TLV-TWA | TLV-STEL | Explosive range |
| 50 ppm | - | 15.5 to 66.9% |
