| Popis: |
In September 2006, the U.S. Environmental Protection Agency established a Federal Reference Method (FRM) for measuring the coarse fraction of particulate matter (PM10-2.5) and promulgated a requirement that states deploy 60 FRM or Federal Equivalent Method PM10-2.5 monitors as a part of the National Core monitoring stations. These FRM monitors are intended to provide the basis for future reviews of the need for a National Ambient Air Quality Standard for PM10-2.5. This article investigates the methodology used to determine ambient concentrations of PM10-2.5 as compared to the true concentration of PM10-2.5. Several urban and rural scenarios are analyzed for PM10, PM2.5, and PM10-2.5 concentrations. The over sampling biases associated with use of current Federal Reference Method PM samplers are shown. |
