The soil resistance (soil resistivity) is expressed in Ohm.cm or Ohm.m. In general, a rough indication of the corrosiveness of the soil compared to the soil resistivity is given
|Soil resistivity (Ohm.cm)||Example||Corrosivity|
|< 2000||Peatlands, forest grounds||Highly corrosive|
|2.000-5.000||loam soil||Corrosive -highly corrosive|
|5.000-10.000||Silt sand||Moderate corrosive|
|> 10.000||Dry sand||very low corrosion rate|
Corrosive soils where oxygen and water are present can lead to external corrosion at damaged areas of the coating. Acidic soils, for example in peatlands and forest areas, and polluted soils where aggressive chemicals can be present are also examples of problematic soil types.
The conductivity of the soil influences the possibility for corrosion to occur and the likelyhood for microbial processes to occur.
The lower the electrical resistance, the higher is the corrosiveness of the soil.