Atmospheric Corrosion Effects of HNO[sub 3]

Abstract

The present trends with decreasing ambient levels and unchanged levels has resulted in an increased interest in as a corrosive pollutant. Despite the fact that ambient levels are still in general much higher than levels, this study shows that 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 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 and one from remaining corrosion stimulators, including . However, an extrapolation of laboratory results of -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.