ATMOSPHERIC CORROSION AT HIGH ALTITUDES OVER SEA LEVEL

摘要

Based on results generated by MICAT/PATINA Projects of the Iberoamerican Program of Science an Technology for Development (CYTED), it has been found differences between the estimation of corrosivity categories with environmental parameters (TOW, SO_2 and Chloride) and those determined from Corrosion Rate measurements. It was assumed also that these differences are associated to the altitude over sea level of the regions where studies were carried out. To explain these differences, local information and other references are used to analyse the effects of factors such as: Drying Rate of The Atmosphere, Atmospheric Pressure, Water Precipitation/Evaporation Rate, NO_2 - O_3 presence and others. The analysis of results showed that there would exist a ΔTOW which should be quantified and taken into account by the international standards, specially ISO 9223 to correct altitude effects for universal application. In addition, it has been stablished that NO_2 - O_3 effect does not depend on altitude but on air contamination levels. The variations of altitude and contamination degree, should be of concern in the estimation of corrosion categories for indoor environments. With an adequate use of the actual information and those to be determined in Projects such as TROPICORR of CYTED.