ISO 9223:2012

ISO 9223: 2012 has established a classification system for atmospheric corrosion of various environments for alloys and metals. It defines the corrosion classes of atmospheric, on the corrosion rate detected in environments for one year on standardised specimens. The norm provides dose-response functions for estimating the corrosivity class, calculated based on normalised metals' annual loss from corrosion. It makes it possible to estimate maximum corrosion class based on the local environment situation knowledge. These consist of the combined effect of temperature and humidity and pollution from sulfur dioxide and salinity.

Corrosivity category for typical external environments

The reference standard does not consider other elements, such as wind speed, sand abrasion, accidental breakage of the protective layer, maintenance frequency, and exposure level. The classifications in the areas shown do not identify solutions or test methods for their suitability.