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 PAINT APPLICATION PROCEDURES
INDEX
Page
General ..........................................................................................
Epoxy-Polyamide Coatings......................................................
Vinyl Paint Coatings........................................................................
Polyurethane Coatings.........................................................
military or federal specifications and standards.
a. Description. Epoxy-polyamide coatings are similar to other epoxy coatings in that they consist of a
two-component system that includes a pigmented polyamide resin (A component) and an epoxy resin (B
component). Once they are mixed together and applied as a paint film, the coating cures to a hard film by
chemical conversion. During this curing period, the solvents used to maintain the composition in liquid
form are released by evaporation.
b. Epoxy Coating Hazards:
(1) Epoxy-polyamides have a minimum flashpoint of 34 C (95 F) and do not require the type of
precautions against fire that are essential to vinyl paints. Since solvent fumes epoxy paint systems are
potentially hazardous, suitable precautions shall be taken to prevent fires and to protect personnel from
fumes and fume inhalation (particularly in confined spaces). Precautions against such hazards must be
exercised at all times.
(2) In addition to fire and vapor hazards, these epoxy coatings can cause allergic reactions when
allowed to be exposed to the skin. Prompt skin cleanup is recommended using soap and water, not
solvent. Solvent will thin and spread the paint over the skin increasing the hazard of a delayed allergic
reaction.
c. Surface Preparation. The single factor most affecting the performance of the epoxy primer coatings is
the preparation of the surface to be coated, both as to method and to degree of care. Surfaces to be
coated should be completely free from rust, loose paint, dirt, scale, oil, grease, salt deposits, moisture,
and other contaminants. Surface preparation procedures detailed in section 3 apply and are
supplemented by requirements given in this section.
(1) Bare Surfaces. When painted surfaces show evidence of corrosion, peeling, blistering, checking,
general disintegration or changing to a new paint system, the old system should be removed down to
bare metal prior to repainting. Surfaces to be painted with the epoxy primer system should be abrasive-
blasted to near-white metal. In areas where abrasive blasting is not permitted, the surfaces should be
cleaned by mechanical means (disk sanding, chipping tools, or pneumatic descaler (needle gun), to
remove all loose paint film and foreign matter. Since abrasive blasting will not adequately clean surfaces
contaminated with oil or grease, such areas should be cleaned with solvent.
(2) Galvanized Steel. Galvanized steel should be roughened by a light abrasive blast or by
mechanical means to provide a suitable painting surface.
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