The present trends with decreasing ambient SO2 levels and unchanged HNO3 levels has resulted in an increased interest in HNO3 as a corrosive pollutant. Despite the fact that ambient SO2 levels are still in general much higher than HNO3 levels, this study shows that HNO3 plays a significant role for the atmospheric corrosion of copper and zinc but not for carbon steel. A comparison of laboratory and field corrosion effects of HNO3 on copper, zinc, and carbon steel is presented. The quantitative agreement between extrapolated laboratory results and field results are good for both copper and zinc and the total corrosion effect can be represented by the sum of two contributions; one from HNO3 and one from remaining corrosion stimulators, including SO2. However, an extrapolation of laboratory results of HNO3-induced corrosion of carbon steel resulted in corrosion effects much lower than the total effect observed in the field. The field data used for comparison are from the international projects model for multipollutant impact and assessment of threshold levels for cultural heritage, with 29 sites in Europe, and Regional Air Pollution in Developing Countries with 12 sites in Asia and 4 in Africa. (c) 2007 The Electrochemical Society.