White Metal Blast Cleaning (SSPC-PC 5 or NACE 1 / SA3)
White metal blast cleaning is used when a totally cleaned surface is required. This method of cleaning is defined as a blast cleaned surface with a groywhite uniform metallic color. It shall be free of all oil, grease, dirt, mill scale, rust, corrosion products, oxides, point, stains, streaks or any other contaminant across 100% of every square inch.
Sandblast Cleaning Steel
Near White Metal Blast Cleaning (SSPC-PC 10 or NACE 2 / SA2.5)
Near-white blast cleaning is defined as one from which all oil, grease, dirt, mill scale, rust, corrosion products, oxides, paint or any other contaminant hove been completely removed from the surface. Very light shadows, very slight streaks or discolorations caused by rust stain, mill scale oxides or slight tight residues of paint or coating are permitted to remain.Only 5% of every square inch may contain the slight discolorations mentioned above.
Commercial Blast Cleaning (SSPC-PC 6 or NACE 3 / SA2)
Commercial blast cleaned surface is defined as one in which all oil, grease, dirt, mill scale, rust and old point have been completely removed from the blast cleaned surface, except that slight streaks, or discolorations caused by rust stain, mill scale oxides, or slight tightly adherent residues of paint or coating may remain. If the surface is pitted, slight residues of rust or paint may remain in the bottom of the pits. The slight discolorations mentioned above ore limited to one-third of every square inch.
Brush-Off Blast Cleaning (SSPC-PC 7 or NACE 4 / SA1)
Brush-off blast is defined as one in which all oil, grease, dirt, rust scale, loose mill scale, loose rust and loose point or coatings ore completely removed. Tight mill scale and tightly adherent rust and paint or coatings may remain as long as the entire surface hos been exposed to abrasive blasting.
Unblast-Before blast Rust Grade "B"
Steel with spreading surface rust and the mill scale commenced flaking.