MIL-HDBK-1110
SSPC SP 1 is specifically included as the first step in the SSPC
surface preparation procedures.
For large areas of uncoated steel and coated steel with
badly deteriorated coatings, the preferred method of removing
mill scale, rust and coatings is abrasive blasting (SSPC SP 7,
SSPC SP 6, SSPC SP 10, SSPC SP 5). These methods can both clean
the surface and produce a surface profile. The specific abrasive
method selected depends upon the conditions of the steel, the
desired coating life, the environment and the coating to be
applied. If leaded paint is present, special precautions must be
taken to protect workers and the environment. Refer to Section
3. High-pressure water blasting, with or without injected
abrasives, should be considered if dry abrasive blasting cannot
be done because of environmental or worker safety restrictions.
For small localized areas, other cleaning methods such
as hand tool cleaning (SSPC SP 2) or power tool cleaning (SSPC
SP 3 or SSPC SP 11) may be more practical.
6.3.3.1
Specific Surface Preparation Requirements for Coatings
for Steel. Different types of coatings may require different
levels of cleaning. Commonly agreed upon minimum requirements
are listed below. However, manufacturers of some specific
coatings may require or recommend a cleaner surface. Conflicts
between manufacturer's written instructions (tech data sheets)
and contract specifications should be avoided.
Coating
Minimum Surface Preparation
Drying Oil
SSPC
SP
2 or SSPC SP 3
Alkyd
SSPC
SP
6 or SSPC-SP 11
SSPC
SP
3 for limited localized areas
Asphaltic
SSPC
SP
6 or SSPC SP 11
Latex
SSPC
SP
6 or SSPC SP 11
Vinyl Lacquer
SSPC
SP
10
Chlorinated Rubber
SSPC
SP
10
Epoxy
SSPC
SP
6 or SSPC SP 10
Polyurethane
SSPC
SP
10
Organic Zinc
SSPC
SP
6 or SSPC SP 10
Inorganic Zinc
SSPC
SP
10 or SSPC SP 5
For immersion or other severe environments, the higher
level of the two options should be used. Higher levels may also
be used to ensure the maximum lives from coating systems.
6.3.4
Galvanized and Inorganic-Zinc Primed Steel. The
recommended method of cleaning uncoated galvanized steel varies
with the condition of its surface. Simple solvent (organic or
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