This joint standard covers the use of blast cleaning abrasives to achieve a defined degree of
cleaning of steel surfaces prior to the application of a protective coating or lining system. This
standard is intended for use by coating or lining specifiers, applicators, inspectors, or others
whose responsibility it may be to define a standard degree of surface cleanliness.
The focus of this standard is industrial blast cleaning. White metal blast cleaning, near-white
metal blast cleaning, commercial blast cleaning, and brush-off blast cleaning are addressed in
separate standards.
Industrial blast cleaning provides a greater degree of cleaning than brush-off blast cleaning
(NACE No. 4/SSPC-SP 7), but less than commercial blast cleaning (NACE No. 3/SSPC-SP 6).
Industrial blast cleaning is used when the objective is to remove most of the coating, mill scale,
and rust, but when the extra effort required to remove every trace of these is determined to be
unwarranted.
The difference between an industrial blast and a brush-off blast is that the objective of a brush-off
blast is to allow as much of an existing coating to remain as possible, while the purpose of the
industrial blast is to remove most of the coating.
A commercial blast is free of mill scale, rust, and coatings, and allows only random staining on
less than 33% of the surface. The industrial blast allows defined mill scale, coating, and rust to
remain on less than 10% of the surface and allows defined stains to remain on all surfaces.
This joint standard was prepared by the SSPC/NACE Task Group A on Surface Preparation by
Abrasive Blast Cleaning. This joint task group includes members of both the SSPC Surface
Preparation Committee and NACE Unit Committee T
