Dose–response functions for weathering steel, copper and zinc obtained from a four-year exposure programme in Switzerland

Abstract Dose–response functions (DRFs) for weathering steel (WTSt 52), copper and zinc were obtained from a four-year exposure programme within Switzerland. Corrosion loss for steel, copper and zinc was investigated at seven sites. The exposure sites were chosen near the stations of the National Air Pollution Monitoring Network (NABEL), where climatic and air pollution data are measured. Corrosion loss was investigated gravimetrically after 1, 2 and 4 years of exposure. The resulting DRFs show a critical contribution of ozone in addition to sulphur dioxide to the corrosion of steel, copper and zinc. The growing demand for environmental protective actions has led to lower atmospheric SO 2 levels as a result of the use of cleaner heating oil and sophisticated gas emission controls. This has increased the relative importance of other atmospheric pollutants like ozone or nitrous oxide for the corrosion of metallic materials.