ASTM D2200-17

4.1 The appearance of the various degrees of dry and wet abrasive blast cleaning, hand and power tool cleaning and water jetting are influenced by the initial rust grades of the steel being cleaned and/or the type and condition of the coating on the existing steel. The standards and guides aid visually in judging and evaluating the degree of rusting and/or paint deterioration before cleaning and the degree of cleaning of steel surfaces prior to painting.

4.2 Five methods have evolved because of differences in the practice of using visual standards and guides throughout the world, and the method of surface preparation employed. In Europe, the visual standards (Method A) are used as the primary means of assessing the degree of cleaning. In the US, the SSPC written definitions take precedence with the visual guides and reference photographs used as a supplement. The visual guides and reference photographs of Methods B, C, and D conform to the SSPC written definitions. There are written definitions for Method E, however, the visual guide for Method E does not contain a complete set of pictorials corresponding to each surface cleanliness definition.

1.1 The visual surface preparation guides and standards consist of a series of color prints available as separate publications. Five different sets of photographs are described in this standard, designated as Method A (ISO/Swedish Standard1.2 The colored visual surface preparation guides represent different conditions of hot rolled carbon steel before and after surface preparation. Prior to cleaning, there are four rust grades, A to D, that cover the range from intact mill scale to 100 % rusted and pitted steel. The standards then depict the appearance of the initial conditions after cleaning by one or more methods (for example, dry abrasive blast cleaning) to various degrees of thoroughness. In addition, Method B includes three painted conditions that contain various degrees of deterioration. The Guide3 depicts these conditions after various degrees of dry abrasive blast cleaning. Method C includes four rust grades and three painted conditions that contain various degrees of deterioration. The Guide1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.