FIELD TESTING AND EVALUATION OF DUST DEPOSITION AND ...

100
Deposition velocity - cm/s
10
1
0.1
0.3
0.4
0.5
0.65
0.8
1
1.6
2
3
4
5
7.5
10
15
20
Physical Diameter - microns
Grand Avg of all the filters excluding SEM 12
Stdev
Figure 3-6. . The grand average deposition velocity (SEM 17, 18, 19) for the SEM samples versus the
particle size. The dashed line represents one standard deviation of the three determinations.
Deposition velocity and standard deviation of replicates data outside the 0.5 m to 5 m range are
not shown due to uncertainty in the accuracy of the data. For d5 m, the results are uncertain due to inlet line
loss.
1.E+10
Concentration - N/m3
1.E+08
1.E+06
1.E+04
1.E+02
1.E+00
0.3
0.4
0.5
0.65
0.8
1
1.6
2
3
4
Physical Diameter - microns
5
7.5
10
15
20
DRI - 12 Utah - 17 Utah - 18, 19
Figure 3-7. Variation in particle concentration between sampling days and between instruments with
different inlet configurations. SEM 12 data were obtained from a GRIMM with a direct sample inlet
and SEM 17, 18, 19 data were obtained from a GRIMM with a 2.5 m long PVC tubing attached to its
sample inlet. For diameters less than 5 m (physical), both the inlets agree but at particle diameters
greater than 5 m, the GRIMM with the long inlet tube exhibited sampling losses. Particle losses
affect deposition velocity calculations.
3-10