Secondary inorganic aerosol

Secondary inorganic aerosol: Ammonium sulphate and ammonium nitrate contribute to PM10 and PM2,5 pollution as secondary inorganic aerosol (SAA) at rural background sites in Austria; in the urban context, its proportion (in case of higher contributions of primary particles) is in a range of about 25-40 %. A significant proportion of this comes from transboundary transport of pollutants. SAA is thus a crucial factor in meeting the objectives of the IG-L or the Air Quality Directive and is addressed because of its cross-border importance through the precursor substances in the NEC Directive. On the basis of literature research on model calculations, building on this, it is shown how the PM2.5 load could develop when the emissions of precursor substances change (Chapter 5). The study examines which precursors in certain regions in Austria can be the limiting factors.