The reason why we mention the reasons causing corrosion is that the main goal of painting the industrial institutions and their products is not only to create a decorative view but also to protect these institutions and manufactured products.
The reasons causing corrosion can be gathered under these three main titles:
 a- The corrosion caused by air and humidity
 b- The corrosion caused by several chemical steam and materials in chemistry institutions
 c- Microbiological corrosion

In order to protect the industrial institutions and the products against corrosion, the contact of the materials causing this problem has to be prevented. The problems are caused by such factors as air, humidity, solvent steam and etc.

Microbiological corrosion is a kind of corrosion which is caused by the bacteria in undeground constructions.

The surface which is to be protected is not likely to be prevented against oxygen and humidity because any materials that are used to prevent this have more or less oxygen and humidity permeability. The corrosion occuring on metals is an electrochemical process. It arises due to the features such as electrolytic dissociation of metals and tendency of oxidation via oxygen. In that case metal, oxygen and water are needed for corrosion. This is to say that the metal surface has to be kept away from water and oxygen.

Corrision happens in different forms depending on ambient conditions. We will move on mentioning the importance of preparing the metals with surface treatment chemicals.