| @ |
 |
Performance
| Measuring Range |
| 0.5 to 1 mg/L |
1 to 14 mg/L |
14 to 28 mg/L |
|
| Number of Pump Strokes |
|
| Correction Factor |
|
| Sampling Time |
1 minute per pump stroke |
| Detecting Limit |
0.1 mg/L (n=2) |
| Colour Change |
Orange → Dark Green |
| Reaction Principle |
Petroleum naphtha + Cr6+ + H2SO4 → Cr3+ |
| Coefficient of Variation |
10% (for 1 to 4 mg/L), 5% (for 4 to 14 mg/L) |
| 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 |
| sulphur dioxide |
500 ppm |
+ |
Green |
| Hydrogen sulphide |
500 ppm |
+ |
Dark brown
( 500 ppm) |
| Acetylene |
3% |
+ |
Dark brown
(whole layer) |
| Propane |
0.2% |
+ |
Dark brown
(whole layer) |
| Organic solvents |
|
+ |
Dark green |
Other substance measurable with this detector tube
| Substance |
Correction Factor |
No. of pump strokes |
Measuring Range |
| Petroleum benzine |
1.0 |
1/2, 1 or 2 |
0.5 to 28 mg/L |
| Petroleum ether |
1.0 |
1/2, 1 or 2 |
0.5 to 28 mg/L |
| Calibration gas generation |
Static gas dilution method |
| TLV-TWA |
TLV-STEL |
Explosive range |
| - |
- |
1.1 to 5.9% |
