Surface preparation grades for primary surface treatment using sandblasting.
| Surface preparation grades | |
| SA 3 | Sandblasting until visibly clean steel To the naked eye, the surface must be free of visible oil, grease, and dirt as well as scale residue, rust, paint layers, and impurities. The surface must have a uniform metallic color. |
| SA 2½ | Very thorough sandblasting To the naked eye, the surface must be free of visible oil, grease, and dirt as well as scale residue, rust, paint layers, and impurities. Remaining traces of contamination must only show in the form of small stains in spots or stripes. |
| SA 2 | Thorough sandblasting To the naked eye, the surface must be free of visible oil, grease, and dirt as well as scale residue, rust, paint layers, and impurities. Remaining contamination must stick. |
| SA 1 |
Light sandblasting |
We occasionally use specifications described as Wa1, Wa2, and Wa2.5 when water jetting.
Additionally, we describe hand cleaning with machine tools using St 2 and St 3.