This standard defines the bases for testing and evaluation the corrosion protection of coated metallic materials by aqueous corrosive media which affect from time to time or permanently the external parts, containers and tubes laid in soil or water or on the internal surface of tubes, containers and apparatus. Electrochemical variables are of importance which are given by contact with uncoated materials, specially by contact with installations of different materials and application of electrochemical protective measures. The standard does not define corrosion protection of coatings by atmospheric attack.