scope:

This tnternationai Standard specifies guiding corrosion values and the characteristics of corrosion for the corrosivity categories defined in IS0 9223.

Guiding corrosion values give corrosion rates for standard structural materials and can be used for engineering calculations. The guiding corrosion values specify the technical content of each of the individual corrosivity categories for these standard metals.

This International Standard can be used to predict the service life for metals, alloys and, in some cases, for metallic coatings used in atmospheres corresponding to different corrosivity categories (see table 1). The guiding corrosion values also provide a technical basis for determining the need for protective measures and other engineering purposes.

The guiding corrosion values are based on experience obtained from a large number of site exposures and service performances. Corrosion rates expected for a given corrosivity category may be exceeded in the vicinity of special design features which cause localized or galvanic corrosion.