BOREAL LASER GasFinder FC, Operation Manual

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Boreal Laser Inc. GasFinderFCr Operation Manual — Appendices July 17th 2017
Appendix G — Calibration
The GasFinderFCr is shipped already calibrated and does not require any calibration in the
fi eld.
The calibration of the
GasFinderFCr is
done by passing a known concentration of
gas through a test cell, which is placed in
the path of the laser beam. Gases which are
very reactive or unstable, such as ammonia
and hydrogen fl uoride, are generated at the
time of use with a permeation tube. The
tube is placed in a temperature-controlled
chamber and emits the calibration gas at a
known rate. A measured fl ow of inert dilution
gas creates a concentration of gas which is
traceable to NIST standards. The calibration
data are stored in the instrument’s software
as a standard reference waveform.
During operation, the GasFinderFCr’s internal reference cell is compared with this stored
waveform at frequent intervals. Any signifi cant deviation generates a status code to alert the
user to a potential calibration problem. The
GasFinderFCr software can be used to check the
reference cell, as well as to download sample, reference, and calibration waveforms (System
Menus/Internal Arrays Transfer) to verify that the system is functioning correctly. If
GasViewOP
is being used, these waveforms can be displayed on the computer (Port1/Arrays Plot Enable
and press the ‘Arrays Transfer’ in the
GasFinderFCr menu).
A technical note detailing the calibration procedure and quality assurance is available from
Boreal Laser Inc.