MIL-HDBK-1138
8.2.1.3
Coating Systems for Concrete. Coating concrete
surfaces for merely cosmetic purposes should be discouraged
because of increased maintenance costs. The coating systems for
concrete surfaces in contact with liquids should be coal-tar
epoxy or polyamide epoxy. Maintenance of coating systems on
concrete substrates generally follows the general procedures used
on steel substrates. However, breakdown of coatings on concrete
can lead to absorption of the fluids into the concrete substrate,
making surface preparation more difficult. In addition, minor
defects in the coating do not develop rust staining, as they do
on steel substrates. Therefore, it is more critical to maintain
a regular inspection program.
Most chemical storage areas will have concrete
containment walls to contain potential spills of the tank
contents. These containment surfaces must be coated with a
suitable coating system capable of withstanding the spilled
chemical. Most monolithic (bonded) coatings will mirror any
cracks that may develop in the concrete. Visually inspect these
areas to detect any leaks of spills through the concrete.
8.2.1.4
Coating Application. High-quality coatings can
usually be applied using the most common coating techniques:
a)
Brush application
b)
Roller application
c)
Conventional spray application
d)
Airless spray application
e)
Trowel application (often for floor coatings)
Because most coating systems are complex, the mixing
and application of coatings requires considerable experience.
It is generally recommended that coating application be left to
qualified applicators.
Routine maintenance can be performed before coating
failures reach the point of requiring major repainting by an
outside contractor. With regular inspection, touch-up of damaged
coatings can be performed using the appropriate, compatible
coating system. Generally, adequate surface preparation can be
accomplished with power or hand tools (SSPC SP2, SSPC SP3, or
SSPC SP11). Surfaces should also be washed to remove any surface
contamination. Application of touch-up paint can best be
accomplished by brush or roller. The newly applied paint should
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