Indicator: 2 to 20 ppm
Measuring Range:
+ 2 to 20 ppm, Number of Pump Strokes 4
+ 20 to 56 ppm, Number of Pump Strokes 2
Sampling Time: 2 minute per pump stroke
Colour Change: Pale yellow → Pale bluish green
Reaction Principle: CH3OH + Cr6+ + H2SO4 → Cr3+
Coefficient of Variation: 15% (for 2 to 5 ppm), 10% (for 5 to 20 ppm)
Nr. of tests: 10
Pump: GV-100S/110S
Catalog
Manual
Performance
| Measuring Range |
|
| Number of Pump Strokes |
|
| Correction Factor |
|
| Sampling Time |
2 minutes per pump stroke |
| Detecting Limit |
0.2 ppm (n=4) |
| Colour Change |
Pale yellow → Pale bluish green |
| Reaction Principle |
CH3OH + Cr6+ + H2SO4 → Cr3+ |
| Coefficient of Variation |
15% (for 2 to 5 ppm), 10% (for 5 to 20 ppm) |
| Shelf Life |
2 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 |
| Alcohols |
|
+ |
Pale bluish green |
| Aromatic hydrocarbons |
|
+ |
Pale bluish green |
| Calibration gas generation |
Diffusion tube method |
| TLV-TWA |
TLV-STEL |
Explosive range |
| 200 ppm |
250 ppm |
6 to 36% |
