Particulate matter regulated, relative size

Move 1] Currently atmospheric particulate matter is regulated based on various size categories because of the apparent association between particle size and adverse health effects. [Move 2] However, the current size-based understanding of atmospheric particles is relatively crude because it does not account for differences in the chemical composition of these particles. Presumably a chemically reactive particle has a greater potential for damage than a chemically inert particle of comparable size. Of the metals potentially... 

FIGURE 18,1 Relative size of regulated particulate matter (PM). 

Criteria pollutants six common pollutants—ozone (O3), carbon monoxide (CO), sulfur dioxide (SO2), nitrogen dioxide (NO2), lead (Pb), and particulate matter less than 10 microns (10 pm) in size—regulated since 1970 in the United States and presenting relatively well quantified risks... 

The two-stage module of the PUF sampler enables determination of suspended particulate matter concentrations by pre- and post-weighing of the four inch glass-fiber filter. Because relative differences in suspended particulate matter are of concern, this evaluation can be performed immediately upon the collection of the samples and can be used to aid site personnel in the assessment of dust suppression techniques and evaluation of meteorological conditions. This technique for the determination of suspended particulate matter concentrations should not be directly compared to national ambient air-quality standard for Total Suspended Particulate (TGP) because the filter size, sample flow rate, and sample volume do not conform to the sampling procedures outlined in the Code of Federal Regulation 0, Part 50.11, Appendix 3 for TSP sampling, however, it does provide accurate re-sult s. ... 

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