TSI Instruments SidePak AM520, Руководство пользователя

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Appendix B 68
All of these options require that a true mass concentration (via
gravimetric analysis) is determined for the aerosol measured. The
true mass concentration is used to calculate the Photometric
Calibration Factor for that aerosol. Further lab analysis of the sample
is required to determine what percentage of the sample represents
the specific substance of interest. This percentage is the associated
Response Factor. Once these values are developed, they can be
used repeatedly to improve measurements in the same or similar
aerosol environment.
Developing a Photometric Calibration Factor for a
Specific Aerosol
The SidePak
™ AM520/AM520i Personal Aerosol Monitor is factory
calibrated to the respirable fraction of standard ISO 12103-1, A1 Test
Dust. The SidePak
™ AM520/AM520i monitor can be easily calibrated
to any arbitrary aerosol by adjusting the photometric calibration factor.
The SidePak
™ monitor’s photometric calibration factor is assigned
the value of 1.00 (factory setting) for the standard ISO test dust. This
procedure describes how to determine the photometric calibration
factor for a specific aerosol. Using a photometric calibration factor
value of 1.00 will always revert back to the factory calibration.
To determine a new photometric calibration factor, a reference
instrument is needed to accurately measure the concentration of
aerosol. Gravimetric analysis is often the best choice, although it is
limited to nonvolatile aerosols.
To develop an accurate photometric calibration factor, a simultaneous
measure must be made of the aerosol concentration with the
SidePak
™ AM520/AM520i monitor and the reference instrument.
N O T I C E
See Application Note EXPMN-014 Developing Photometric
Calibration Factor for Respirable Silic a, and Application Note
EXPMN-013 Developing Photometric Calibration Factors for Diesel
Particulate Matter .