This NACE International standard designates where, how often, and the most likely places to test for the presence of surface soluble salts before application of a coating system. This standard establishes industry best practices for soluble salt testing frequencies and locations. It provides a consistent method of soluble salt testing for inclusion in written directions and specifications prepared by asset owners, engineers, consultants, coating contractors, inspectors, and others who are specifying allowable levels of surface soluble salts to prevent premature coating failures. This standard applies only to previously coated substrates and replacement substrate material, and does not include allowable limits of soluble salts.