This standard specifies the definition, inspection method and evaluation and calculation method of coating damage area for ship ballast ships. It is applicable to the evaluation and calculation of the damaged area of coatings in ships' special seawater ballast tanks and Sanganshan double side parts painting that meet the requirements of the "Protective coating performance standard for seawater medium holds and bulk carriers for all types of ships" (PSPC) formulated by the Internet Standard Organization (MIO). The standard is applicable to the evaluation and calculation of the damaged area of coatings during painting of ship cabins.