Factory calibration of the gas analyzers goes beyond the standard field calibration:
-
All gas analyzers are calibrated in a custom built calibration facility.
Each gas analyzer undergoes a series of calibration routines and checks
in a stable computer controlled environment.
-
Each gas analyzer is thermally cycled, to determine correction coefficients
for changes in measured parameters due to changes in temperature. A series
of certified gas mixtures is passed through each gas analyzer (while at a
fixed temperature) and the changes in output recorded.
-
Using sophisticated computer analysis techniques, the 'gas data curve' for
each gas analyzer is fitted accurately to the certified values of the gases,
and the calibration information is programmed in to the memory of each
analyzer. This data can not be lost or replaced in any way by the user.
-
When programmed, the calibration accuracy of the gas analyzer is checked at
two different temperatures, using a series of certified gas mixtures, which
includes values not previously passed through the instrument. This data is
recorded and utilized to produce the instrument-specific calibration certificate.
-
All calibrated gas analyzers are dispatched with a full
certificate of calibration,
and a copy of the inspection check sheet.
The quality of the calibration gas is of utmost importance:
-
The gas mixtures used are purchased from specialist gas suppliers,
who are approved under our quality system . The base
gases used to create our requested mixtures are pure gases, whose content of
other gases is negligible. The calibration of the equipment used to produce
the gas mixtures is traceable to National Standards (NIST) of weight,
volume, temperature and pressure through the quality systems of our suppliers.
The gas concentrations are certified to an analytical precision of 2% of
component (e.g. for 15% gas 0.30% absolute) or better.
-
With regards to authorization, all of our procedures are audited to conform to
an overall quality standard. This means that our calibration procedures
have been checked for competency
and consistency to ensure all gas analyzers receive the same level of attention.
Therefore all measurements taken, checked and verified are against controlled
equipment that is checked to traceable standards.