EN 14789 - Oxygen by Paramagnestism Flashcards
What is the principle of paramagnetism?
EN 14789
- Oxygen molecules highly attracted to magnetic field
- Gas exposed to magnetic gradient in confined space constrains oxygen to flow in the direction of the magnetic field
- Magnitude of flow is dependent on the concentration of oxygen
EN 14789
Is paramagnetism a dry or wet gas technique?
EN 14789
Dry
EN 14789
Should the filter upstream of the sample line be heated?
EN 14789
Yes
EN 14789
What temperature must the gas be conditioned to?
EN 14789
Outlet temperature of ≤ 4°C
EN 14789
What is allowable for the zero check following zero and span gas calibration?
EN 14789
No significant change on the zero reading
EN 14789
What is the allowable deviation on the pre-test zero and span gas line checks?
EN 14789
< 2% of the span gas value
EN 14789
What specification of zero gas is required?
EN 14789
Nitrogen (Free of oxygen < 0.05%)
EN 14789
What specification of span gas is required -
EN 14789
Oxygen
(Expanded uncertainty ≤ 2%)
EN 14789
What is maximum allowable analyser response time?
EN 14789
200 seconds to reach 90% of the range
EN 14789
What is the allowable lack of fit (linearity) and how often must the analyser be checked for lack of fit?
EN 14789
≤ 0.3% v/v checked at least once a year
EN 14789
What is the allowable uncertainty at a 95% confidence interval?
EN 14789
± 6% of the measured value expressed on a dry gas basis, or 0.3% v/v, whichever is greater
EN 14789
What is the stated range of the method?
EN 14789
3% v/v to 21% v/v
EN 14789
What is the allowable post-test drift?
EN 14789
0 to 2% - no drift correction is applied
2 to 5% - drift correction is applied
> 5% - drift test fails and test must be reperformed
EN 14789
What is the required span gas for the method?
EN 14789
Ambient (dried) air or cylinder gas with an uncertainty of ≤ 2%
EN 14789
