Evaluation of PM10 and Total Suspended Particulate Sampler Performance Through Wind Tunnel Testing

Particulate matter (PM) concentrations in ambient air can be monitored by gravimetric sampling near a source using Federal Reference Method (FRM) samplers. PM is regulated by size, with PM10, which is comprised of particles with aerodynamic equivalent diameters less than or equal to 10 μm, being the main focus of this research. FRM PM10 samplers exhibit sampling errors when sampling dusts with mass median diameters (MMDs) that are larger than the 10 μm sampler cutpoint. For industries to be regulated equitably, these sampler errors must be quantified and understood. This research evaluates the performance of FRM PM10 and low volume total suspended particulate (TSP) samplers under the controlled conditions of a wind tunnel. The performance evaluation was conducted by observing the sampler cutpoints, slopes, and measured concentrations. These measured values were compared to values obtained using a collocated isokinetic reference sampler. The results of this research indicate that PM10 samplers do not operate as intended under all conditions. The cutpoint of the PM10 inlets was significantly higher than the maximum FRM limit of 10.5 μm when sampling dust with MMDs larger than the cutpoint of the sampler. The slope values for the PM10 inlets were significantly higher than the maximum FRM limit of 1.6. MMDs and geometric standard deviations of PM collected by TSP samplers were significantly different than those of PM collected using the collocated isokinetic sampler. The concentrations measured by the TSP samplers were significantly higher than the collocated isokinetic sampler. The results of this research provide a better understanding of the performance of TSP and PM10 samplers operating under different conditions and shows that these samplers are not operating as intended. Because of this, industries may be suffering the consequences of inequitable regulation