This NACE/SSPC joint standard defines the Clean to Bare Substrate (WJ-1) degree of surface cleanliness of coated or uncoated metallic substrates achieved by the use of waterjet cleaning prior to the application of a protective coating or lining. Waterjet cleaning is the use of pressurized surface preparation water for removing coatings and other materials, including hazardous materials, from a substrate to achieve a defined degree of surface cleanliness. Waterjet clean- ing includes various methods such as low-pressure water cleaning (LP WC), high-pressure water cleaning (HP WC), high-pressure waterjetting (HP WJ), and ultrahigh-pressure waterjetting (UHP WJ).
This standard contains requirements for three performance levels of primer coatings used to protect ferrous substrates that contain zinc as the major pigment component. Individual products meeting minimum perfor- mance requirements of this standard may vary in formulation, raw materials, and application characteristics. The specifier selects the appropriate performance level. If no Level is specified, Level II becomes the default. SSPC-Paint 20 is a formulation-based standard for inorganic or organic zinc-pigmented coatings that includes options for specifying higher zinc loading levels in the dry coating film,