Airshed

An airshed is a part of the atmosphere that behaves in a coherent way with respect to the dispersion of emissions. It typically forms an analytical or management unit. Also: a geographic boundary for air-quality standards. An airshed is a part of the atmosphere that behaves in a coherent way with respect to the dispersion of emissions. It typically forms an analytical or management unit. Also: a geographic boundary for air-quality standards. Alternatively - an airshed is a geographical area where local topography and meteorology limit the dispersion of pollutants away from the area.