A Comparative Analysis of Airborne Fine Particulate Matter Sampling Devices

The United States Environmental Protection Agency regulates airborne particulate matter and requires ambient air monitoring for particles with a nominal size of approximately 2.5 μm or less (PM2.5) to be performed using an instrument which meets the requirements of its reference method which is published in 40 CFR Part 50, Appendix L. This type of sampling device provides results which are limited in that they represent the average total concentration over a twenty-four hour period, with no information regarding particle size distribution or temporal changes during that time period. An evaluation of two potential alternative sampling devices, a quartz crystal microbalance cascade impactor and a low flow parallel stage impactor, was performed. These studies showed that it is potentially possible to estimate the PM2.5 concentration using the quartz crystal microbalance instrumentation, potentially with a correction factor from the calculated linear regression equation, but not the low flow parallel stage impaction instrumentation.