TSI Instruments SidePak AM520, Руководство пользователя

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Custom Calibrations 69
Photometric Calibration Factor Procedure
1. Set up photometer and sampling pump in similar manner.
•
SidePak
™ AM520/AM520i (with Dorr-Oliver Cyclone if
measuring respirable size fraction).
•
Sample pump with a sampling cassette (with Dorr-Oliver
Cyclone if measuring respirable size fraction).
2. Adjust flow rate for appropriate inlet conditioner (if used).
•
Flow rate set to 1.7 L/min for both instruments if using
Dorr-Oliver Cyclone.
3. Zero the photometer and calibrate the sample pump prior
to sampling.
4. Co-locate both samplers side-by-side either in a work area or on
a worker in the breathing zone.
5. Start photometer and sampling pump at same time, sample for
same duration.
•
Data log aerosol measurements with photometer.
•
Collect gravimetric sample with sample pump.
•
Sample time does not need to be full shift like compliance
monitoring. The key is to collect at least the minimum volume
necessary for valid analysis with the analytical method.
6. Sample a few locations to gather data. ( NOTE: Ideally use a
statistically significant number of samples to properly represent
the worker population
.)
•
Review gravimetric data as it becomes available.
•
Conduct more sampling if considerable data variability
is found.
7. Send gravimetric samples to accredited analytical lab.
8. Compare photometric and gravimetric data.
•
Calculate averages for each from representative number of
samples.
•
If sample variability is high, collect more samples to improve
the representation of the sample population.
9. Calculate new photometric calibration factor using the
formula below.