Solvent Cleaning SSPC-SP1

Solvent cleaning is a method for removing all visible oil, grease, soil, drawing and cutting compounds, and other soluble
contaminants from steel surfaces. Water washing with appropriate cleaning chemicals is an acceptable solvent cleaning
method. All surfaces should be cleaned according to these guidelines prior to using hand tools or blast equipment.

Hand Tool Cleaning SSPC-SP2 (Swedish Standard St2)

Hand tool cleaning describes the method of surface preparation involving wire brushing, scraping, chipping and sanding.
While it is not the most recommended method of surface preparation, it can be used under mild exposure conditions.
Protective coatings seldom perform at optimum levels when this method is used.

Power Tool Cleaning SSPC-SP3 (Swedish Standard St3)

Power tool cleaning describes a mechanical method of surface preparation widely used in industry. It involves the use of
power sanders or wire brushes, power chipping hammers, abrasive grinding wheels, needle guns, etc. Although usually
more effective than hand tool cleaning, it is not considered appropriate for use under severe exposure conditions or for
immersion applications.

White Metal Blast Cleaning SSPC-SP5/ISO-8501-1 SA 3/ NACE#1

Surfaces when viewed without magnification, shall be free from all visible oil, grease, dust, dirt, mill scale, rust, coating,
oxides, corrosion products and other foreign matter.

Near-White Metal Blast Cleaning SSPC-SP10/ ISO 8501-1 SA 2.5/ NACE#2

Surfaces when viewed without magnification, shall be free from all visible oil, grease, dust, dirt, mill scale, rust, coating,
oxides, corrosion products and other foreign matter, for each unit area. Staining should be limited to no more than 5%
of each unit area, and may consist of light shadows, slight streaks, or minor discolourations caused by stains of rust, mill
scale or previously applied coatings.

Commercial Blast Cleaning SSPC-SP6/ ISO 8501-1 SA2 / NACE #3

Surfaces when viewed without magnification, shall be free from all visible oil, grease, dust, dirt, mill scale, rust,
coating, oxides, corrosion products and other foreign matter, for each unit area. Light shadows, slight streaks, or minor
discolorations caused by stains of rust, stains of mill scale, or stains form previously applied coating in less than 33% of
the unit area is acceptable.

Brush-off Blast Cleaning SSPC-SP7/ISO8501-1 SA1/NACE#4

Surfaces when viewed without magnification, shall be free of all visible oil, grease, dirt, dust, loose mill scale, loose rust,
and loose coating. Tightly adherent mill scale, rust and coating may remain on the surface. Mill scale, rust, and coating are
considered tightly adherent if they cannot be removed by lifting with a dull putty knife.

Water Jetting SSPC-SP12/NACE#5

Water Jetting is the use of a high-energy water stream to strip off existing coatings and prepare them for the application
of (new) protective coatings. This method has some specific advantages over dry abrasive blasting, especially with
respect to worker safety and worker air quality. In particular, respiratory requirements may be less stringent than those for
other methods of surface preparation. Unlike abrasive blasting, it does not produce a surface profile on smooth steel but
instead exposes any original abrasive blasted profile.
These standard definitions apply:
• Low-Pressure Water Cleaning (LP WC): Cleaning performed at pressures below 5,000 psi (34 MPa)
• High-Pressure Water Cleaning (HP WC): Cleaning performed at pressures of 5,000 to 10,000 psi (34 to 70 MPa)
• High-Pressure Water Jetting (HP WJ): Cleaning performed at pressures of 10, 000 psi to 25,000psi (70 to 170MPa)
• Ultrahigh-Pressure Water Jetting (UHP WJ): Cleaning performed at pressures above 25,000psi (170MPa)

Power Tool Cleaning to Bare Metal SSPC-SP11

This standard covers the requirements for power tool cleaning to produce a bare metal surface and to retain or produce a
minimum 25 micrometer (1.0 mil) surface profile. This standard is suitable where a roughened, clean, bare metal surface is
required, but where abrasive blasting is not feasible or permissible.

Aluminium

The surface should be clean, dry and grease-free (see under Steel – Degreasing). If any corrosion salts are present they
should be removed by lightly abrading. Before painting, apply one thin coat of etch primer to provide a key for further
coats. This can also be achieve by lightly blasting with fine non-metallic abrasive (e.g. Garnet or Aluminium oxide).

Brass, Bronze, Copper and Lead

Contaminants should be removed with a combination of water, detergents and solvents (same as aluminium). Allow the
metal to dry, then power- or hand-abrade to remove oxides. This can also be achieved by very light abrasive blasting
using low-pressure and non-metallic abrasive.

Galvanised Metal

The surface should be clean, dry and grease-free (see under Steel – Degreasing). Degreasing of most galvanised surfaces
requires some effort to obtain a clean surface. Any white zinc corrosion products should be removed by high-pressure
fresh water washing, or fresh water washing with scrubbing. When using the preferred method of surface preparation,

i.e. sweep blasting, it is still advisable to fresh water-wash to remove soluble zinc salts. Many coatings based on non-
saponifiable polymers can be applied directly to galvanised surfaces prepared in this way. When sweep blasting is not

possible, an acid etch primer should be used to passivate the surface and provide a key for further paint coatings. Details
of coatings that can be applied to sweep-blasted galvanised steel, and suitable etch primers, can be obtained from
Nippon Paint Protective Coatings Handbook.

For other products, please contact your Nippon Paint representative.