CH3Br |
|
Performance
Measuring Range |
|
Number of Pump Strokes |
|
Correction Factor |
|
Sampling Time |
2 minutes per pump stroke |
Detecting Limit |
0.2 ppm (n=2) |
Colour Change |
White → Yellow |
Reaction Principle |
2CH3Br +I2O5+ H2S2O7 → Br 2
Br 2 +O-Tolidine → Yellow product |
Coefficient of Variation |
10% (for 1 to 6 ppm), 5% (for 6 to 18 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 |
Hologenes, NOx |
|
+ |
Yellow |
Saturated halogenated hydrocarbons |
|
+ |
Yellow |
Other substance measurable with this detector tube
Substance |
Correction Factor |
No. of pump strokes |
Measuring Range |
n-Butyl Bromide |
1.0 |
2 |
1 to 18 ppm |
n-Butyl Bromide |
2.4 |
1 |
2.4 to 43.2 ppm |
n-Propyl Bromide |
1.0 |
2 |
1 to 18 ppm |
Chloro bromomethane |
0.7 |
2 |
0.7 to 12.6 ppm |
Calibration gas generation |
Permeation tube method |
TLV-TWA |
TLV-STEL |
Explosive range |
1 ppm |
- |
10 to 15% |