TSI Instruments SidePak AM520, User Manual

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Appendix B
Custom Calibrations
In most situations, the Model AM520/AM520i provides very good
information on how the concentration of an aerosol changes for over
time. Factory calibration to the respirable fraction of standard
ISO 12103-1, A1 Test Dust (aka, Arizona Test Dust) allows
comparisons between measurements where the source or type of
dust is predominately the same. Because optical mass
measurements are dependent upon particle size and material
properties, there may be times when a custom calibration will improve
your accuracy for a specific aerosol.
The SidePak
™ AM520/AM520i monitor has several features to aid in
obtaining good accuracy for a specific aerosol.
•
The SidePak
™ monitor’s User Calibration Factor includes both a
Photometric Calibration Factor (PCF) and Response Factor (RF).
The PCF is used to tune the instrument mass concentration
response to the specific aerosol. The RF is used to monitor the
level of a specific substance consisting of a known percentage of
that aerosol.
•
The SidePak
™ monitor’s User Calibration Factor can be changed
through the instrument keypad. All future readings from the
SidePak
™ monitor will correspond to a specific aerosol until the
calibration factor is changed back to the factory setting.
•
User Calibration Factors can be stored in a table and
downloaded to the SidePak
™ monitor using the TrakPro™ Data
Analysis Software. All future measurements will correspond to a
specific aerosol until the calibration factor is changed back to
the factory setting.
•
A single set of logged data can be converted to data calibrated to
a specific aerosol with the use of the TrakPro
™ software. This
conversion can be done by knowing either the true mass
concentration for the logged data or the calibration factor for the
aerosol. Future measurements will continue to be read and
logged with the original calibration factor (normally 1.0) and will
not be converted automatically.