| CH3Br |
 |
Performance
| Measuring Range |
| 2.5 to 10 ppm |
10 to 100 ppm |
100 to 200 ppm |
|
| Number of Pump Strokes |
|
| Correction Factor |
|
| Sampling Time |
3 minutes per pump stroke |
| Detecting Limit |
0.5 ppm (n=4) |
| Colour Change |
White → Yellow |
| Reaction Principle |
2CH3Br +I2O5+ H2S2O7 → Br 2
Br 2 +O-Tolidine → Yellow product |
| Coefficient of Variation |
10% (for 10 to 20 ppm), 5% (for 20 to 100 ppm) |
| Shelf Life |
2 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 |
| Chlorine, Bromine, NOx |
|
+ |
Yellow |
| Saturated halogenated hydrocarbons |
|
+ |
Yellow |
Other substance measurable with this detector tube
| Substance |
Correction Factor |
No. of pump strokes |
Measuring Range |
| Chlorobromomethane |
1.1 |
1 |
11 to 110 ppm |
| 1,1-Dibromoethane |
0.7 |
1 |
7 to 70 ppm |
| 1,2-Dibromoethane |
0.8 |
1 |
8 to 80 ppm |
| Dibromomethane |
0.5 |
1 |
5 to 50 ppm |
| Ethyl Bromide |
1.0 |
1/2, 1, 4 |
2.5 to 200 ppm |
| n-Butyl Bromide |
1.0 |
1 |
10 to 100 ppm |
| Benzyl bromide |
by scale |
1 |
10 to 100 ppm |
| Bromoform |
by scale |
1 |
1 to 50 ppm |
| Calibration gas generation |
Permeation tube method |
| TLV-TWA |
TLV-STEL |
Explosive range |
| 1 ppm |
- |
10 to 15% |
