-9-8.SURFACE PREPARATION METHODSQuality of the surface preparation seriously affects performance of paint film. It is necessary to clearly determine the method and the grade of surface preparation in the painting specification before contracting the painting work. The inspector and the painters should preferably work in concert to ensure the quality of the surface preparation before commencement of the work.The methods of surface preparation are detailed in the Steel Structures Painting Manual, Vol. 2. The pictorial standards were prepared by the Swedish Corrosion Institute and have been jointly approved by the American Society for Testing and Materials, the Steel Structure Painting Council as the Swedish Standard Association.The terms used in the surface preparations specified by the Steel Structures Painting Council are shown on Table 4.The related specifications are compared on Table 5.SP 1, Solvent CleaningSP 2, Hand Tool CleaningSP 3, Power Tool CleaningSP 5, White Metal Blast CleaningSP 6, Commercal Blast CleaningSP 7, Brush-Off Blast CleaningSP 8, PicklingSP 10, Near-White Blast CleaningB, C, D St2 B, C, D St3A, B, C, D Sa3C, D Sa2B, C, D Sa1B, C, D Sa2 1/2*Vis 1, pictorial surface preparation standards for painting of steel surfaces.Photographic standards used as specification; optional supplement to SSPC Surface Preparations 2, 3, 5, 6, 7 and 10.Table 4 Definitions of Surface Preparations (Steel Structures Painting Manual Vol. 2, SSPC)Removal of oil, grease, dirt, soil, salts, and contaminants by cleaning with solvent, vapor, alkali, emulsion, or stream.Removal of loose rust, loose mill scale, and loose paint to degree specified, by hand chipping, scraping, sanding, and wire brushing.Removal of loose rust, loose mill scale, and loose paint to degree specified, by power tool chipping, descaling, sanding, wire brushing, and grinding.Removal of all visible rust, mill scale, paint, and foreign matter by blast cleaning by wheel or nozzle (dry or wet) using stand, grit, or shot, (For very corrosive atmospheres where high cost of cleaning is warranted.)Blast cleaning until at least two-thirds of the surface area is free of all visible residues. (For rather severe conditions of exposure.)Blast cleaning of all except tightly adhering residues of mill scale, rust, and coatings, exposing numerous evenly distributed flecks of underlying metal.Complete removal of rust and mill scale by acid pickling, duplex pickling or electrolytic pickling.Blast cleaning nearly to White Metal cleanliness, until at least 95% of the surface area is free of all visible residues. (For high humidity, chemical atmosphere, marine, or other corrosive environments.)DescriptionSSPC-Vis 1*PhotographSSPC Specification