Offshore metallic structures have an average life-time of 20-25 years. They consist of four different zones, the buried, the submerged, the tidal/splash and the atmospheric one. According to NACE 2013 the global corrosion cost is estimated to be US$2.5 trillion, consisting a major economic problem. Hence, protection from corrosion is essential. Each zone is protected either with cathodic methods, or with a combination of cathodic methods and coatings. More specifically, the protection of the atmospheric zone, which is the aim of this research, due to the lack of continuous electrolyte (seawater) does not allow the application of cathodic protection.