Correcting Pm10 Over-Sampling Problems for Agricultural Particulate Matter Emissions: Preliminary Study

Abstract

The Federal Reference Method (FRM) ambient PM 10 sampler does not always measure the true PM 10 concentration. There are inherent sampling errors associated with the PM 10 samplers due to the interaction of particle size distribution (PSD) and sampler performance characteristics. These sampling errors, which are the relative differences between theoretical estimation of the sampler concentration and the true concentration, should be corrected for equal regulation between industries. An alternative method to determine true PM 10 concentration is to use the total suspended particulate (TSP) concentration and PM 10 fraction of the PSD in question. This article reports a new theoretical method to correct PM 10 sampling errors for a true PM 10 /TSP ratio. The new method uses co-located PM 10 /TSP samplers' measurements to derive the mass median diameter (MMD) of PSD and true PM 10 /TSP ratio. Correction equations and charts have been developed for the PMs with GSDs of 1.2, 1.3, ..., 2.1, respectively, and the PM 10 sampler with a cutpoint of 10 mm and slope of 1.5. These equations and charts can be used to obtain a corrected PM 10 /TSP ratio for the given GSD and sampler characteristics. The corrected PM 10 /TSP ratio will be treated as the true PM 10 /TSP ratio for PM 10 concentration calculations. This theoretical process to obtain a corrected PM 10 /TSP ratio will minimize the inherent PM 10 sampler errors and will provide more accurate PM 10 measurement for the given conditions.

Synthesis, crystal structure and electrochemistry properties of [Cd(phen)(H2O)4](ClO4)Cl · H2O

“…The four oxygen atoms (mean Cd1-O1w 0.2201 nm) are from four coordination water molecules, and the two nitro gen atoms locating at neighboring positions are from one chelating phen ligand (mean Cd1-N1 0.2220 nm). The Cd-N distances are in accord with those values previ ously reported for six coordinated cadmium(II) com plexes [23], although they are slightly shorter than those distances normally found in seven and eight coordinated cadmium(II) complexes. Such shorten ing may be explained on the basis of the decreased coordination number of cadmium [24][25][26].…”

Managing Agricultural Emissions to the Atmosphere: State of the Science, Fate and Mitigation, and Identifying Research Gaps

“…Physical characteristics of emission sources, particle‐size distributions of the PM emitted, and natural dispersion of emissions into the environment cause difficulties in quantifying PM emissions from agricultural operations (Wanjura et al, 2009). Because uncertainties in emissions are considered substantial, extensive research has been done on correcting and improving existing methodologies as well as developing new methods and information (Wang et al, 2005; Waite et al, 2005; Simon et al, 2008; Wanjura et al, 2009). There continues to be a significant research need for accurate methods to quantify particulate emissions from agricultural operations.…”

Particulate Matter Concentration and Air Quality Affected by Windblown Dust in the Columbia Plateau

“…Concurrent measurements of PM fine and PM10 using federal reference method filter-based samplers were made on 20% of the days. Although the same type of sampler was used to measure both PM fine and PM10 on any given day, inadequacies of the sampler design to capture only PM fine or PM10 (Buser et al, 2003;Wang et al, 2005) will contribute to inaccuracies in measuring PM coarse . However, similar trends in the frequency distribution of days with various levels of PM coarse were found using data collected by both the federal reference method filter-based sampler and TEOM.…”