| SO2 |
 |
Performance
| Measuring Range |
0.5 to
1 ppm |
1 to
20 ppm |
2 to
30 ppm |
30 to
60 ppm |
|
| Number of Pump Strokes |
|
| Correction Factor |
|
| Sampling Time |
1 minute per pump stroke |
| Detecting Limit |
0.1 ppm (n=8) |
| Colour Change |
Blue → Yellow |
| Reaction Principle |
SO2 + BaCl2 +H2O BaSO3 + 2HCl
HCl+Base Chloride |
| Coefficient of Variation |
10% (for 2 to 10 ppm), 5% (for 10 to 30 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 colour by itself to |
Carbon monoxide,
Nitric oxide |
|
No |
No |
| Carbon dioxide |
100% |
Unclear demarcation |
Unclear demarcation |
| Nitrogen dioxide |
1/1 |
+ |
Pale purple |
| Hydrogen sulphide |
|
No |
No |
Other substance measurable with this detector tube
| Substance |
Correction Factor |
No. of pump strokes |
Measuring Range |
| Thionyl chloride |
0.72 |
2 |
1.44 to 21.6 ppm |
| Calibration gas generation |
Permeation tube method |
| TLV-TWA |
TLV-STEL |
Explosive range |
| 2 ppm |
5 ppm |
- |
