Section 4: Particulate Matter Sampling
Airmetrics
23
Figure 4.1.
Mounted Sampler
Airmetrics MiniVol Users Guide
24
Airmetrics
Figure 4.2.
Tubing Configuration for PM Sampling Mode
Before tra nsporting the Min iVol to the field, perform a laborato ry check to
determine if it is operational. Turn the sampler on and observe the motor
performance. Check all tubing for crimps, cracks or breaks. Conduct a flow check
with a "dummy" filter in place to simulate the load against the sampler pump.
Investigate and correct any malfunctions before proceeding. Perform a single-point
flow rate check using a soap-bubble meter or other flow measuring device of
known accuracy and compare to the curve established during calibration. The flow
should b e within ± 15% of 5 lpm at current c onditions . If the unit fails to operate
in this range, check the sampler for o bvious crimp s, battery malfunc tion,
etc
. The
sample r must be repaired o r recalibrate d if the flow criteria are n ot met.
F
LOW
R
ATE
The pa rticle size cu t point of the presepa rator is a fun ction of the velocity w ith
which the air stream passing through the preseparator hits the target. The
preseparator is designed to have the correct cut point at an air flow rate of 5 lpm at
