What is Paint or Paint Definition:

A Paint is a coating or covering material applied on a metallic or non-metallic surfaces for

decorative or protective purposes. Most commonly they may be a protective as well as

decorative finish.

Paints can be defined as: ” A liquid solution of pigment ( coloring material ) and solvent, which

is applied on different surfaces for decorative or protective reasons “. OR

It can also be defined as: ” Dispersion of a pigment ( coloring substance ) in a suitable drying oil

in the presence of a solvent ( paint thinner ) is known as paints”.

Qualities of Good Paints:

Following are its basic qualities.

1. Good Hiding Power:

It should be capable of covering the existence surface of a material uniformly and thoroughly.

2. Color:

Good paints must maintain its color under all atmospheric conditions or in any other

circumstance.

3. Resistance:
Paints should be chemically inert to the atmosphere. This is essential if it has to protect the

underlying surface of a metal.

4. Easy Application:

They might have to be used over wide surface areas. It is therefore, necessary that it should be of

such a nature that it can spread easily , smoothly and uniformly.

5. Economical in Cost:

Types of Paint should be selected according to the construction, its cost should be as low as

possible. Costly paints should not be used in common constructions.

6. It should dry in reasonable time.

7. It should form hard and durable surface.

8. It should not be harmful to the health of workers.

9. It should possess attractive and pleasing appearance.

10. It should form a thin film of uniform nature i.e., it should not crack.

11. It should dry in reasonable time.

Components of Paint:

Paints are prepared by intimately mixing various components in proper proportions. Following

are essential components of paint.

(1.) The Vehicle:

It is actually an oil which is dried on exposure to air. Hence it is also called a drying oil.

Such oil is unsaturated in composition. On exposure to air it gets saturated ( and hence dries out )

The drying oil or the vehicle has the capacity to keep the pigment and other components of paint

in suspension or solution. These ingredients get deposited in the film, made by the drying oil on

the surface of an object.

The most commonly used vehicle or drying oils are: Linseed oil, dehydrated castor oil, bleached

oil and fish oil.

Driers are those substances which are added to drying oils to accelerate the rate of drying. They

act as catalysts in the oxidation process of the drying oils.

The linoleats, resinates and naphthanates of metals like lead, magnesium and vanadium are

commonly used drier.

(2.) Base:

A base is a solid substance that forms the body of the paint. It consist of a very fine powder of a

suitable material such as white lead, red lead, iron oxide and titanium oxide etc.
The base material makes the paints film harder, stronger, elastic and safe against cracking

and moisture. It makes the paint stable against Ultra Violet

(3.) The Pigments:

It is a coloring material added to the above components in order to impart a desired shade and

color. A pigment is added in a finely powdered state.

In White color paints: White Lead, Titanium White, Lithophone are used as a pigment.

In Red Color: Red Lead, Venetian Red, Chrome Red, Natural Red Oxides of Iron are used as a

pigment.

In Yellow Color: Chrome Yellow, Zinc Chromate, Yellow Ochres are used as a pigment

In Brown Color: Oxides of Iron is used as a pigment.

In Blue Color: Pursian Blue, Paris Blue, Ultramarine, Cobalt Blue are used as a pigment.

Rays as well.

4.) Solvents ( Paint Thinner ):

They are also called Paint thinner, which reduce the viscosity of the paints to a great extent.

Solvents (paint thinner) or added to paints in order to make its application easy, smooth and

uniform.
Petroleum, spirits, turpentine and coal tar hydrocarbons are some of commonly used solvents or

paint thinner.

(5.) Extenders:

They are also called fillers, A Filler is a substance which can be added to paints to increase its

bulk volume without effecting its useful properties.

These materials ( Fillers ) are necessarily inert towards other components of paint. Commonly

used extenders are: Chalk, gypsum, barite, silica and and magnesium silicate.

Types of Paints

Depending upon their constituents there are various types of paints. A brief description of some

of them

which are commonly used are given below:

1. Oil Paint: These paints are applied in three coats-primer, undercoat and finishing coat. The

presence of dampness while applying the primer adversely affects the life of oil paint. This paint

is cheap and easy to apply.

2. Enamel Paint: It contains white lead, oil, petroleum spirit and resinous material. The surface

provided by it resists acids, alkalis and water very well. It is desirable to apply a coat of titanium

white before the coat of enamel is applied. It can be used both for external and internal walls.

3. Emulsion Paint: It contains binding materials such as polyvinyl acetate, synthetic resins etc.

It dries in 1,5 to 2 hours and it is easy to apply. It is more durable and can be cleaned with water.

For plastered surfaces, first a coat of cement paint should be applied and then the emulsion point.

Emulsion paint needs sound surfaces.

4. Cement Paint: It is available in powder form. It consists of white cement, pigment and other

additives. It is durable and exhibits excellent decorative appearance. It should be applied on

rough surfaces rather than on smooth surfaces. It is applied in two coats. First coat is applied on

wet surface but free from excess water and allowed to dry for 24 hours. The second coat is then

applied which gives good appearance.

5. Bituminous Paints: This type of paint is manufactured by dissolving asphalt or

vegetable bitumen in oil or petroleum. It is black in colour. It is used for painting iron works

under water.

6. Synthetic Rubber Paint: This paint is prepared from resins. It dries quickly and is little

affected by weather and sunlight. It resists chemical attack well. This paint may be applied even

on fresh concrete. Its cost is moderate and it can be applied easily.

7. Aluminum Paint: It contains finely ground aluminum in spirit or oil varnish. It is visible in

darkness also. The surfaces of iron and steel are protected well with this paint. It is widely used

for painting gas tanks, water pipes and oil tanks.

8. Anti-corrosive Paint: It consists essentially of oil, a strong dier, lead or zinc chrome and

finely ground sand. It is cheap and resists corrosion well. It is black in colour.

Why is surface preparation important before painting?

Durability of any painting coat depends upon complete and careful preparation of the surface

before painting. The surface should be even and smooth. Any cracks, and holes or any other

imperfections do not let the paint adhere correctly to the surface. Inadequate surface preparation

results into majority of paint failures.

Surface preparation techniques vary according to the type of surfaces. Interior and exterior

surfaces even cannot follow the same procedure. Similarly, it would vary considering its fresh
painting or repainting. In case of repainting, it is not necessary to remove entire, existing paint

layer, but to remove all loose flakes. Painting over the broken pieces can result in coming off of

the old paint along with the new paint.

1. Wall Cleaning :

2. To remove dirt, dust, black spots fungi. These impurities may not be visible, but they are

usually present on the wall since they restrict the ability of the coating to stick to the wall

entirely. To properly prepare new metal surfaces, use mineral spirits to remove grease

and apply a rust-inhibitive primer before painting. For painted surfaces that are in sound

condition, remove dust with a clean, dry cloth, de-gloss the surface with light sanding,

and wipe with mineral spirits to ensure good adhesion. To remove persistent dirt, wash

surfaces with a mild detergent solution or with a commercial product recommended for

cleaning painted surfaces.

3. Remove loose and peeling paint. If the old paint is in poor condition, you can remove it

by hand wire brushing, sanding, or scraping. You can also opt for power tool cleaning,

which can help remove paint quickly and easily. However, one drawback of using power

tools is that they can polish metal surfaces, potentially causing paint-adhesion problems.

4. Remove rust. When preparing metal for paint, checking for rust is important to make

sure that the paint will adhere properly to the surface. To restore lightly rusted metal

surfaces to their original state, use a brush to clean off loose rust, sand the area, and apply

a high-quality rust-inhibitive primer (e.g. Rust-Oleum Rust Reformer). Also known as

rust converters, rust-inhibitive primers can be used to cover rusted spots and turn them

into non-rusting, paintable surfaces.

 5. Repair small holes and dents. To repair holes and dents, sand the area until you reach

bare metal and wipe with a degreaser mixed with mineral spirits. For small holes and

dents, inject an appropriate epoxy-based composite directly into the hole and/or dent. For

larger holes, apply epoxy filler to the edge of the hole, cut a piece of fiberglass mesh

approximately one inch larger than the hole, and press it into the filler. Then, cover the

mesh with epoxy, working your way from the edge toward the center of the hole.

6. Fixing Wall Dampness : Checking the wall for dampness is another vital step. Wet and

discolored patches on the wall indicate the presence of humidity. Bacteria find their home

in surface irregularities like gaps, hairline cracks, and small holes. These bacteria that are

present on the wall contaminate the room atmosphere and can cause significant health

issues. So the gaps need to be filled and smoothed with sanding paper.

1. Priming : Primer helps hide the dark surfaces and patched areas. Applying a coat of
primer helps the surface look uniform in shade. Moreover, priming increases life of paint,
as it helps in its adhesion on to the surface. Priming is a very important step in preparing
metal for paint, especially if the surface will be exposed to moisture. To select the right
primer, the type of surface to be coated along with the desired appearance, performance
requirements, and environmental conditions should be considered. To begin with, water-
based (latex) primers shouldn’t be used on metal surfaces, as moisture can seep through
and cause paint to fail within weeks or months. Professionals recommend two types of
metal primers: the rust converters mentioned above and galvanized metal primers. While
a rust converter is ideal for preventing rust from recurring and making a rusted surface
easier to paint, a galvanized primer is appropriate for metals (e.g. aluminum) that prevent
paint from adhering to the surface. You can also find iron oxide and zinc chromate
primers, which can be used on most metal surfaces, including interior and exterior iron
and steel.

Priming immediately after cleaning the surface is imperative to prevent dust or dirt from
accumulating and flash rust (rust that occurs within hours) from forming.

The complete wall surface preparation job consists of cleaning, repairing, patching, sanding,

masking, and priming. Each surface preparation technique is used for different reasons and holds
its unique importance. Thoroughly applying each step will give a well-prepared surface and

ultimately a finely done painting job.

SURFACE PREPARATION METHODS

MINIMAL PREPARATION
For coatings requiring only minimal surface preparation, the surface needs to be prepared in
accordance to SSPC-SP 1 and SSPC-SP 2 or SSPC-SP 3. Tightly adhered rust, mill scale or
previous coating can remain provided it cannot be removed by lifting with a dull putty knife
using moderate pressure. Use SSPC-SP 7 (NACE 4) to expedite the preparation of large areas.

CHEMICAL CLEANING METHOD

SSPC–SP 1: Chemical Cleaning
This method involves the removal of dirt, oil, grease and other foreign materials with organic
solvents, detergents or commercial cleaners using one of several cleaning methods such as
wiping, steam cleaning, or vapor degreasing. Use one or more of the following techniques.

Chemical Cleaning Methods

Pure Strength Cleaner/Degreaser: Removes dirt, grease, oil, adhesives, road tar, and more.
Agitate for one minute before use. Apply directly on the surface, rub with a brush or cloth, and
rinse thoroughly with clean water or wipe with a damp cloth. For large jobs dilute
Cleaner/Degreaser with water. All surfaces must be dry before coating is applied.

Steam Cleaning: Recommended for removing grease, oil, salt, acid, alkali, and similar chemical
residue from large areas. For maximum effectiveness, steam cleaning should be used in
combination with alkaline cleaning. The surface must be thoroughly dry and free of residue
before it is coated.

Alkaline Cleaning: For removal of dust, dirt, wax, grease, oil, fat, salt, acid residue, etc., scrub
surface with a strong commercial detergent solution such as trisodium phosphate (TSP), then
flush thoroughly with fresh water. Surface must be completely dry and free of any residue before
it is coated.

Volatile Solvent Cleaning: Make certain the area is well ventilated. Apply solvent to the surface
with cloths, sponges, or brushes and scrub to remove grease and oil. Several successive wipings
are usually necessary, using clean cloths and solvent each time. For optimum results follow with
Alkaline Cleaning.

HAND AND POWER TOOL CLEANING METHODS

SSPC–SP 2: Hand Tool Cleaning

Loose rust, loose mill scale and deteriorated coatings can be removed by effective use of hand
and power tools. Brush-Off Grade Blasting (SSPC-SP 7) cleans to the same requirements and
may be used as an alternative to scraping and wire brushing. Prior to scraping and wire brushing,
remove grease, oil, salt, chemical dust, and other contaminants by Chemical Cleaning. Removal
of heavy rust scale, light mill scale, or previous coatings over extensive areas usually requires
Commercial Grade Blast Cleaning (SSPC-SP 6) or Industrial Blast Cleaning (SSPC-SP-14).

Chip, scrape, or wire brush rusted surfaces thoroughly to produce a tightly adhered surface that is
clean and free of foreign matter to assure good coating adhesion. Care must be taken with power
tools to avoid polishing a metal surface or abrading it too deeply. Tightly adhered coatings which
are very hard or glossy should be sanded to remove gloss and slightly roughen the surface. This
will contribute to maximum adhesion of the new coating. Examine existing coatings carefully for
signs of rust beneath the coating. If present, remove coatings in these areas.

SSPC–SP 3: Power Tool Cleaning

Loose rust, loose mill scale and deteriorated coatings can be removed by effective use of hand
and power tools. Brush-Off Grade Blasting (SSPC-SP 7) cleans to the same requirements and
may be used as an alternative to scraping and wire brushing. Prior to scraping and wire brushing,
remove grease, oil, salt, chemical dust, and other contaminants by Chemical Cleaning. Removal
of heavy rust scale, light mill scale, or previous coatings over extensive areas usually requires
Commercial Grade Blast Cleaning (SSPC-SP 6) or Industrial Blast Cleaning (SSPC-SP-14).

Chip, scrape, or wire brush rusted surfaces thoroughly to produce a tightly adhered surface that is
clean and free of foreign matter to assure good coating adhesion. Care must be taken with power
tools to avoid polishing a metal surface or abrading it too deeply.

Tightly adhered coatings which are very hard or glossy should be sanded to remove gloss and
slightly roughen the surface. This will contribute to maximum adhesion of the new coating.
Examine existing coatings carefully for signs of rust beneath the coating. If present, remove
coatings in these areas.

SSPC–SP 11: Power Tool Cleaning to Bare Metal

Power tool cleaning to produce a bare metal surface and to retain or produce a surface profile.
This cleaning specification exceeds SSPC-SP 3 Power Tool Cleaning in that it requires complete
removal of all visible oil, grease, dirt, mill scale, rust, paint, oxide, corrosion products, and other
foreign matter. Slight residues of rust and paint may be left in the lower portions of pits if the
original surface is pitted. If the surface is to be roughened, the surface profile produced shall be
not less than 1 mil (25μ) and shall be to a degree suitable for the specified paint system.

SSPC–SP 15: Commercial Grade Power Tool Cleaning

Power tool cleaning to produce a bare metal surface. Remove all visible oil, grease, dirt, mill
scale, rust, paint, oxide, corrosion products, and other foreign material. Random staining is
allowed provided it is limited to no more than 33% per unit area of surface. A surface profile of 1
mil (25μ) shall be produced.
PRESSURIZED WATER CLEANING METHODS
These standards provides requirements for the use of high and ultra-high pressure water jetting to
achieve various degrees of surface cleanliness. This standard is limited in scope to the use of
water only without the addition of solid particles in the stream. These standards define four
levels of working pressure:

SSPC-SP WJ-1/NACE WJ-1: Waterjet cleaning of metals. Clean to bare substrate.

SSPC-SP WJ-2/NACE WJ-2: Waterjet cleaning of metals. Very thorough cleaning.
SSPC-SP WJ-3/NACE WJ-3: Waterjet cleaning of metals. Thorough cleaning.
SSPC-SP WJ-4/NACE WJ-4: Waterjet cleaning of metals. Light cleaning.

This cleaning standard defines 4 levels of cleanliness for visible contamination by water jetting
and 3 levels for non-visible contamination, such as chlorides and other soluble salts. See the full
standard for complete definitions on the level of cleanliness.

ABRASIVE BLAST CLEANING METHODS

Abrasive blast is the most effective method of cleaning steel and masonry surfaces prior to
coating. It is mandatory for certain specialized applications such as water immersion and high
temperature exposure. Recommended for removal of mill scale, heavy rust scale, and previous
coatings from large areas. Careful selection of equipment, nozzles, and abrasives are essential to
economical operation and achievement of the desired results. Avoid using coarse abrasives. 18–
40 mesh sand or grit will provide the 2 to 2.5 mil 50–62μ) blast profile recommended for use
with most coating systems.

For optimum results, follow this sequence:

1. Prior to blast cleaning, remove grease, oil, salt, chemicals, dusts, and similar contaminants by
Chemical Cleaning.
2. Prior to blast cleaning, remove all weld spatter.
3. Abrasive blast to one of the grades described below.
4. After blasting, remove all abrasive, dust and grit with a vacuum cleaner, clean and dry
compressed air, or a clean brush.
5. Blasted surfaces should be coated on the same day they are blasted before the cleaned surface
can become contaminated.

SSPC–SP 5 (NACE 1): White Metal Blast Cleaning

Completely remove all mill scale, rust, rust scale, previous coating, etc., leaving the surface a
uniform gray-white color.

SSPC–SP 6 (NACE 3): Commercial Grade Blast Cleaning

Completely remove all dirt, rust scale, foreign matter, and previous coating, etc., leaving
shadows and/or streaks caused by rust stain and mill scale oxides. Random staining shall be
limited to no more than 33% of each unit area of surface (a unit of area is defined as 9 square
inches).

SSPC–SP 7 (NACE 4): Brush-Off Blast Cleaning

Remove rust scale, loose mill scale, loose rust, and loose coatings, leaving tightly bonded mill
scale, rust, and previous coatings. This is an ideal method for removing oxides and/or loose and
peeling coatings from galvanized metal. Results are comparable to those achieved by through
chipping, scraping, and wire brushing.

SSPC–SP 10 (NACE 2): Near White Metal Blast Cleaning

Remove all rust scale, mill scale, previous coating, etc., leaving only light stains from rust, mill
scale, and small specks of previous coating. Random staining shall be limited to no more than
5% of each area of surface (a unit of area is defined as 9 square inches).

SSPC–SP 14 (NACE 8): Industrial Blast Cleaning

Removal of all visible oil, grease, dust, and dirt. Traces of tightly adherent mill scale, rust, and
coating residues are permitted to remain on 10% of each unit area of the surface if they are
evenly distributed (a unit of area is defined as 9 square inches). The traces of mill scale, rust, and
coating shall be considered tightly adhered if they cannot be lifted with a dull putty knife.
Shadows, streaks, and discoloration caused by stains of rust, stains of mill scale, and stains of
previously applied coating may be present on the remainder of the surface.

CONCRETE, MASONRY, PLASTER AND WOOD (FLOORS OR WALLS)

New or Uncoated: Allow new substrate to cure thoroughly before coating. This requires 30 days
under normal curing conditions. If there is any doubt about the dryness of the substrate, conduct
a test by placing a weighted rubber mat, plastic sheet, or other non-porous material on the
substrate for 24 hours. Then, check the underside of the mat and the substrate for signs of
moisture. The substrate will be darker if damp. If moisture is found, substrate is too damp to coat
with solvent-based coatings. Allow additional drying time of 10 to 14 days. Repeat test. If
moisture persists, substrate cannot be coated (ASTM D 4263-83).

Very dense, non-porous, or finished concrete must be acid etched, or abrasive blasted, to assure
proper coating penetration. Determine porosity by pouring about one ounce of water onto the
substrate. If water soaks in, the concrete is porous enough for coating. If it beads up on the
surface, the concrete is not porous enough, and treatment is warranted. All surfaces must be free
of grease, oil, wax, salt, dirt, and other contaminants. Remove with one of the chemical cleaning
methods. Acid etch with Rust-Oleum 108 Cleaning & Etching Solution (ASTM D 4260-83).

Uncoated Wood
Remove all loose dirt, dust, etc., by sweeping or vacuum cleaning. Remove floor compound or
wax by appropriate method. The surface must be thoroughly dry before coating.

Coated Concrete and Wood

Remove loose dirt, dust, etc., by sweeping or vacuum cleaning. Remove grease, oil, floor
compound, or wax by Chemical Cleaning. Scrape or sand carefully to remove deteriorated
coatings. On concrete, deteriorated paint is best removed by abrading surfaces (ASTM D 4259-
83). If remaining coating is glossy or very hard, sand it lightly for good adhesion of subsequent
coatings. The surface must be thoroughly dry before coating. 6000 and 6500 Systems can be
 applied over most existing floor coatings without lifting them. Refer to SSPC 13 (NACE 6) for
additional and more complete information regarding the surface preparation of concrete.

Mildewed Surfaces
Surfaces with mold and mildewed areas should be cleaned with an alkaline cleaning solution and
rinsed with water. If any mold or mildew remains on the surface, clean further with one quart of
household bleach added to a gallon of water. Rinse with clean water. Severely mildewed areas
should be cleaned with a chlorinated cleansing powder and thoroughly rinsed with water.
Improperly prepared surfaces can result in reduced coating integrity and service life. Up to 80%
of all coatings failures can be directly attributed to inadequate surface preparation, which affects
coating adhesion.
To ensure adhesion of the coating to the substrate and prolong the service life of the coating
system, select and implement the proper surface preparation. The method of surface preparation
depends on the substrate, the environment, and the expected life of the coating system.
Economics and surface contamination (including its effect on the substrate) will also influence
the selection of surface preparation methods.
 The surface must be dry and in sound condition.
 Remove mildew, oil, dust, dirt, loose rust, peeling paint or other contamination to ensure good
adhesion.
 No exterior painting should be done immediately after a rain, during foggy weather, when rain is
predicted, or when the temperature is below 50°F - unless the coating indicates it can be used
down to 35°F. Most coatings are now formulated for low temperature use.
The table below provides an overview of proper surface preparation for a variety of common
substrates.
Preparation Steps by Surface Type
Aluminum
Remove all oil, grease, dirt, oxide and other foreign material by cleaning per SSPC-SP1, Solvent
Cleaning.
Block (Cinder and Concrete)
Remove all loose mortar and foreign material from block. Surface must be free of laitance,
concrete dust, dirt, form release agents, moisture curing membranes, loose cement, and
hardeners.
 Concrete and mortar must be cured at least 30 days at 75°F.
 The pH of the surface should be between 6 and 9.
 On tilt-up and poured-in-place concrete, commercial detergents and abrasive blasting may be
necessary to prepare the surface.
 Fill bug holes, air pockets, and other voids with a cement patching compound.
Brick
Brick must be free of dirt, loose and excess mortar, and foreign material.
 All brick should be allowed to weather for at least one year followed by wire brushing to remove
efflorescence.
 Treat the bare brick with one coat of Loxon Conditioner.
Concrete
The following guides will help assure maximum performance of the coating system and
satisfactory coating adhesion to concrete:
1. Cure - Concrete must be cured prior to coating application. Cured is defined as concrete poured
and aged at a material temperature of at least 75°F for at least 30 days. The pH of the surface
should be between 6 and 9.
2. Moisture - (Reference ASTM D4263) Concrete must be free of moisture as much as possible
(moisture seldom drops below 15% in concrete). Test for moisture or dampness by taping the 4
edges of an 18 inch by 18 inch plastic sheet (4 mils thick) on the bare surface (an asphalt tile or
other moisture impervious material will also do), sealing all of the edges. After a minimum of 16
hours, inspect for moisture, discoloration, or condensation on the concrete or the underside of the
plastic. If moisture is present, the source must be located and the cause corrected prior to
painting.
3. Temperature - Air, surface and material temperature must be at least 50°F (10°C) during the
application and until the coating is cured.
4. Contamination - Remove all grease, dirt, loose paint, oil, tar, glaze, laitance, efflorescence, loose
mortar, and cement by the recommendations A, B, C, or D, listed below.
5. Imperfection may require filling with a material compatible with Sherwin-Williams coatings.
6. Concrete Treatment - Hardeners, sealers, form release agents, curing compounds, and other
concrete treatments must be compatible with the coatings, or be removed.

Concrete - Blast Cleaning

(Reference ASTM D4259) Brush Blasting or Sweep Blasting-Includes dry blasting, water
blasting, water blasting with abrasives, and vacuum blasting with abrasives.
1. Use 16 - 30 mesh sand and oil-free air.
2. Remove all surface contamination (ref. ASTM D4258). See Method "D" below.
3. Stand approximately 2 feet from the surface to be blasted.
4. Move nozzle at a uniform rate.
5. Laitance must be removed and bug holes opened.
6. Surface must be clean and dry (moisture check: ref. ASTM D4263) and exhibit a texture similar
to that of medium grit sandpaper.
7. Vacuum or blow down and remove dust and loose particles from the surface (ref. ASTM
D4258).

Concrete - Acid Etching

 The following guides will help assure maximum performance of the coating system and
satisfactory coating adhesion to concrete:
1. Remove all surface contamination (ref. ASTM D4258).
2. Wet surface with clean water.
3. Apply a 10 - 15% Muriatic Acid or 50% Phosphoric Acid solution at the rate of one gallon per
75 square feet.
4. Scrub with a stiff brush.
5. Allow sufficient time for scrubbing until bubbling stops.
6. If no bubbling occurs, the surface is contaminated with grease, oil, or a concrete treatment which
is interfering with proper etching. Remove the contamination with a suitable cleaner (ref. ASTM
D4258, or Method "D" below) and then etch the surface.
7. Rinse the surface two or three times. Remove the acid/water mixture after each rinse.
8. Surface should have a texture similar to medium grit sandpaper.
9. It may be necessary to repeat this step several times if a suitable texture is not achieved with one
etching. Bring the pH (ref. ASTM D4262) of the surface to neutral with a 3% solution of
trisodium phosphate or similar alkali cleaner and flush with clean water to achieve a sound, clean
surface.
10. Allow surface to dry and check for moisture (ref. ASTM D4263).
Concrete - Power Tool Cleaning or Hand Tool Cleaning
1. Use needle guns or power grinders, equipped with a suitable grinding stone of appropriate size
and hardness, which will remove concrete, loose mortar, fins, projections, and surface
contaminants. Hand tools may also be used.
2. Vacuum or blow down to remove dust and loose particles from surface (ref. ASTM D4258, or
Method "D" below).
3. Test for moisture or dampness by taping the 4 edges of an 18-inch by 18-inch plastic sheet (4
mils thick) on the bare surface (an asphalt tile or other moisture impervious material will also
do), sealing all of the edges. After a minimum of 16 hours, inspect for moisture, discoloration, or
condensation on the concrete or the underside of the plastic. If moisture is present, the source
must be located and the cause corrected prior to painting.
Concrete - Surface Cleaning
The surface must be clean, free of contaminants, loose cement, mortar, oil, and grease. Broom
cleaning, vacuum cleaning, air blast cleaning, water cleaning, and steam cleaning are suitable as
outlined in ASTM D4258.
Concrete curing compounds, form release agents, and concrete hardeners may not be compatible
with recommended coatings. Check for compatibility by applying a test patch of the
recommended coating system, covering at least 2 to 3 square feet. Allow concrete to dry one
week before testing adhesion per ASTM D3359. If the coating system is incompatible, surface
preparation per methods outlined in ASTM D4259 are required.
Cement Composition Siding/Panels
Remove all surface contamination by washing with an appropriate cleaner, rinse thoroughly and
allow siding to dry.
Existing peeled or checked paint should be scraped and sanded to a sound surface.
Glossy surfaces should be sanded dull.
Pressure clean, if needed, with a minimum of 2100 psi to remove all dirt, dust, grease, oil, loose
particles, laitance, foreign material, and peeling or defective coatings. Allow the surface to dry
thoroughly.
If the surface is new, test it for pH, many times the pH may be 10 or higher.
Copper
Remove all oil, grease, dirt, oxide and other foreign material by cleaning per SSPC-SP 2, Hand
Tool Cleaning.
Drywall - Interior/Exterior
Drywall must be clean and dry. All nail heads must be set and spackled. Joints must be taped and
covered with a joint compound. Spackled nail heads and tape joints must be sanded smooth and
all dust removed prior to painting.
Exterior surfaces must be spackled with exterior grade compounds.
Exterior Composition Board (Hardboard)
Some composition boards may exude a waxy material that must be removed with a solvent prior
to coating. Whether factory primed or unprimed, exterior composition board siding (hardboard)
must be cleaned thoroughly and primed with an alkyd primer.
Galvanized Metal
Allow galvanized metal to weather a minimum of 6 months prior to coating.
Solvent clean per SSPC-SP1, then prime as required.
When weathering is not possible or the surface has been treated with chromates or silicates, first
Solvent Clean per SSPC-SP1 and apply a test area, priming as required.
Allow the coating to dry at least one week before testing.
If adhesion is poor, Brush Blast per SSPC-SP7 is necessary to remove these treatments.
Plaster
Plaster must be allowed to dry thoroughly for at least 30 days before painting.
The room must be ventilated while drying. In cold, damp weather, rooms must be heated.
Damaged areas must be repaired with an appropriate patching material.
Bare plaster must be cured and hard.
Textured, soft, porous, or powdery plaster should be treated with a solution of 1 pint household
vinegar to 1 gallon of water. Repeat until the surface is hard, rinse with clear water and allow to
dry.
Previously Coated Surfaces
Maintenance painting will frequently not permit or require complete removal of all old coatings
prior to repainting. However, all surface contamination such as oil, grease, loose paint, mill
scale, dirt, foreign matter, rust, mold, mildew, mortar, efflorescence, and sealers must be
removed to assure sound bonding to the tightly adhering old paint.
Glossy surfaces of old paint films must be clean and dull before repainting. Thorough washing
with an abrasive cleanser will clean and dull in one operation, or, wash thoroughly and dull by
sanding.
Spot prime any bare areas with an appropriate primer.
Recognize that any surface preparation short of total removal of the old coating may compromise
the service length of the system. Check for compatibility by applying a test patch of the
recommended coating system, covering at least 2 to 3 square feet. Allow surface to dry one week
before testing adhesion per ASTM D3359. If the coating system is incompatible, complete
removal is required (per ASTM 4259, see Concrete, S-W 5, "Blast Cleaning" above).
Steel - Structural Plate
Steel should be cleaned by one or more of the nine surface preparations described below. These
methods were originally established by the Steel Structures Council in 1952, and are used
throughout the world for describing methods for cleaning structural steel. Visual standards are
available through the Steel Structures Painting Council; ask for SSPC-Vis 1-67T.
Steel - Solvent Cleaning
Solvent cleaning is a method for removing all visible oil, grease, soil, drawing and cutting
compounds, and other soluble contaminants. Solvent cleaning does not remove rust or mill scale.
Change rags and cleaning solution frequently so that deposits of oil and grease are not spread
over additional areas in the cleaning process. Be sure to allow adequate ventilation.
Steel - Power Tool Cleaning
Power Tool Cleaning removes all loose mill scale, loose rust, and other detrimental foreign
matter. It is not intended that adherent mill scale, rust, and paint be removed by this process.
Before power tool cleaning, remove visible oil, grease, soluble welding residues, and salts by the
methods outlined in SSPC-SP 1.
Steel - White Metal Blast Cleaning
A White Metal Blast Cleaned surface, when viewed without magnification, shall be free of all
visible oil, grease, dirt, dust, mill scale, rust, paint, oxides, corrosion products, and other foreign
matter.
Before blast cleaning, visible deposits of oil or grease shall be removed by any of the methods
specified in SSPC-SP 1 or other agreed upon methods.
Steel - Commercial Blast Cleaning
Staining shall be limited to no more than 33 percent of each square inch of surface area and may
consist of light shadows, slight streaks, or minor discolorations caused by stains of rust, stains of
mill scale, or stains of previously applied paint.
Before blast cleaning, visible deposits of oil or grease shall be removed by any of the methods
specified in SSPC-SP 1 or other agreed upon methods.
Steel - Brush-Off Blast Cleaning
A Brush-Off Blast Cleaned surface, when viewed without magnification, shall be free of all
visible oil, grease, dirt, dust, loose mill scale, loose rust, and loose paint.
Tightly adherent mill scale, rust, and paint may remain on the surface.
Before blast cleaning, visible deposits of oil or grease shall be removed by any of the methods
specified in SSPC-SP 1 or other agreed upon methods.
Steel - Power Tool Cleaning to Bare Metal
Metallic surfaces which are prepared according to this specification, when viewed without
magnification, shall be free of all visible oil, grease, dirt, dust, mill scale, rust, paint, oxide
corrosion products, and other foreign matter. Slight residues of rust and paint may be left in the
lower portions of pits if the original surface is pitted. Prior to power tool surface preparation,
remove visible deposits of oil or grease by any of the methods specified in SSPC-SP 1, Solvent
Cleaning, or other agreed upon methods.
Steel - Near-White Blast Cleaning
A Near White Blast Cleaned surface, when viewed without magnification, shall be free of all
visible oil, grease, dirt, dust, mill scale, rust, paint, oxides, corrosion products, and other foreign
matter, except for staining.
Staining shall be limited to no more than 5 percent of each square inch of surface area and may
consist of light shadows, slight streaks, or minor discolorations caused by stains of rust, stains of
mill scale, or stains of previously applied paint. Before blast cleaning, visible deposits of oil or
grease shall be removed by any of the methods specified in SSPC-SP 1 or other agreed upon
methods.
Steel - Water Blasting
Removal of oil grease dirt, loose rust, loose mill scale, and loose paint by water at pressures of
2,000 to 2,500 psi at a flow of 4 to 14 gallons per minute.
Stucco
Must be clean and free of any loose stucco.
If recommended procedures for applying stucco are followed, and normal drying conditions
prevail, the surface may be painted in 30 days.
The pH of the surface should be between 6 and 9.
Wood - Exterior
Wood must be clean and dry.
Prime and paint as soon as possible. Knots and pitch streaks must be scraped, sanded, and spot
primed before a full priming coat is applied.
Patch all nail holes and imperfections with a wood filler or putty and sand smooth.
Caulk should be applied after priming.
Wood - Interior
All finishing lumber and flooring must be stored in dry, warm rooms to prevent absorption of
moisture, shrinkage, and roughening of the wood.
All surfaces must be sanded smooth, with the grain, never across it.
Surface blemishes must be corrected and the area cleaned of dust before coating.
Vinyl Siding
Vinyl siding must be cleaned thoroughly by scrubbing with a warm, soapy water solution. Rinse
thoroughly.