[Emissions of dust and microbes from animal housing]

The content of airborne dust and germs in animal houses is described qualitatively and quantitatively. After having left the animal house by way of the exhaust air the microorganisms suffer a decay which is caused by dispersion and death-rate. The dispersion can be demonstrated by models. The boundary of the dispersion of germs and dust is about 200 m from source under normal conditions. Epidemiologic studies indicate that some virus particles can be transported over several miles by way of the air. Control of airborne dust and germ levels in animal houses is still poor.