“…The characteristics of PM (e.g., concentration, number, and mass) inside livestock housing vary according to the type of animal, building, and environmental conditions. Previous studies (Li et al, 2011;Green et al, 2007;Lim et al, 2007;Heber et al, 2005;Vucemilo et al, 2007;Shuhai et al, 2009) showed that the mean PM concentration measured inside layer housed (cage system) were 1.96, 0.33, 0.032 mg/m 3 for TSP, PM 10 , and PM 2.5 , respectively. The ranges of these concentrations were 0.75-4, 0.03-0.56, and 0.03-0.04 mg/m 3 for TSP, PM 10 , and PM 2.5 , respectively.…”