Theoretical study of effect of particle size distribution in livestock houses on equivalence of gravimetric PM10 measurement methods

This study investigates whether differences in particle size distribution (PSD) across livestock categories explain the varying relationships observed between PM 10 mass concentration measurements obtained using a gravimetric method with an impactor pre-separator (IPS) and an alternative method with a cyclonic pre-separator (CPS) in livestock houses. A theoretical analysis was conducted using estimated PSDs for laying hens, broilers, and fattening pigs, derived from literature data. Estimated fractional efficiency curves for both IPS and CPS were calculated based on their physical characteristics. The theoretical sampled PM 10 fractions for each method and livestock category were subsequently calculated and used to evaluate the theoretical ratio between IPS and CPS PM 10 measurements. Since the most likely IPS/CPS relationships identified in the sensitivity analysis in this study are significantly smaller than those reported in empirical studies, it is improbable that PSD is the sole predictor of the IPS/CPS relationship in livestock houses. However based on this study it cannot be excluded that the estimated differences in PSDs among livestock categories are large enough to exclusively cause the empirically found differences between IPS and CPS measurements. • A gravimetric method with a cyclonic pre-separator was compared to the EN12341 reference sampler across multiple livestock categories. • A theoretical analysis was conducted using estimated particle size distributions, derived from literature data • Estimated fractional efficiency curves for both samplers were estimated based on their physical characteristics. • Results show that PSD is not likely the sole predictor of the IPS/CPS relationship in livestock houses