Measurement of particle size distribution in a swine building

The majority of the research in animal buildings has been on measured concentrations of contaminants that the workers and animals are exposed to; emission measurements have only gained attention in recent years due to potential federal regulations on air quality emissions from animal feeding operations (AFOs). The contribution of AFOs to ambient PM ₁₀ and PM _2.5 entails reliable measurement of particle size distribution. The objective of this study was to measure and compare the size distribution of particulate matter (PM) at multiple locations inside and at the exhausts of a wean-to-finish commercial swine building. The particle size distribution was measured by collecting total suspended particulate matter on Teflon filters and using Coulter Counter and Horiba LA-300 analyzers for particle size distribution analyses. Results showed that the mass median diameter (MMD) of swine PM at the exhaust was about 14% lower than the average MMD indoors (26.84 vs. 31.55 μm), while the geometric standard deviations were about the same (1.85 vs. 1.86). In addition, the average percentage by volume of PM ₁₀ indoors was about 8%, while the percentage of PM ₁₀ leaving the building was 10%. In terms of the mass concentrations, PM ₁₀ indoors ranged from 0.014 to 0.125 mg m ^-3, while at the exhaust PM ₁₀ ranged from 0.02 to 0.15 mg m ^-3. This study will aid in understanding the exposure of workers to particles indoors and in quantifying the contribution of a commercial swine building to emissions of PM ₁₀ in the atmosphere.