Atmosphere corrosion is corrosion which occurs when metal and alloys are exposed to outdoor and indoor atmospheres but are not immersed in a liquid. Coatings resistant to atmosphere corrosion are expected to withstand rain, sun, wind and other weather conditions. Immersion corrosion is corrosion which occurs when metals or alloys are exposed to liquids and are subject to total, partial or alternate immersion. Protective coatings must resist the environment at, below and above the liquid line. Practical experience showed than Zinc and Aluminum sprayed layer offer a good protection against corrosion and that the maintenance cost are far below coatings from coats of paint.