Atmospheric Environments

Atmospheric corrosion can vary widely depending on contaminants present, humidity and rainfall, wind and temperature. Extensive atmospheric testing programs have been conducted to compute corrosion rates of metals and to characterize metals’ susceptibilities to various forms of corrosion. A typical atmospheric testing rack is shown in Figure 1. Such studies have lead to the broad categorization of environments into rural, urban, industrial, marine, and combinations of them. A general characterization of the four main types is listed in Table 1.

Deviations of corrosion rates within the four categories have lead to a further subcategorization based upon weather and climate. These additional factors influencing corrosion are temperature, humidity and rainfall. The relative corrosion rates for these environments are found in Table 1.