MIL-HDBK-1110
c) Paint - Textured, tacky, and peeling paint pick up
and retain spores and dirt; incompletely removed mildew may
rapidly reinfect new paint; drying oils in paints may be used as
nutrients. Mildewcides in paints can control the growth of
mildew organisms.
5.19.2
Use of Mildewcides in Paints. Mercury-containing
mildewcide additives were used very successfully in paints for
many years to control mildew growth. Only a small amount of the
mercury compound leaching from the paint was necessary to kill
microorganisms. Unfortunately, it also contaminated the
environment with toxic material. Thus, mercury-containing
mildewcides are no longer used in paints. EPA has approved
alternative nonmercurial compounds for use as paint mildewcides.
Some of these products, however, have not proven to be effective
in retarding mildew growth.
5.19.3
Removal of Mildew. Mildew must be killed before
repainting a mildewed surface to obtain control of the mildew.
If spores are just painted over, the mildew will quickly grow and
become unsightly. When a surface is to be cleaned for
repainting, scrub with a solution of 2/3 cup of trisodium
phosphate, 1 liquid ounce of household detergent, 1 quart of
5-1/4 percent sodium hypochlorite (available as household
bleach), and 3 quarts of warm water. Use rubber gloves with this
caustic solution and rinse it from the surface with water after
scrubbing. It will degrade alkyd and other oil-based coatings,
but this will be no problem, if the surface is to be repainted.
An alternate procedure is to remove all the visible mildew by
waterblasting at about 700 pounds per square inch (psi) and kill
the rest by rinsing with a solution of 1 quart of 5-1/4 percent
sodium hypochlorite and 3 quarts of warm water.
If a painted surface is to be merely cleaned without
repainting, apply the scrubbing solution without the trisodium
phosphate to avoid damage to the paint. Apply it first to a
small test area to see if the hypochlorite bleaches the paint.
If it does, merely clean with detergent and water.
Mildew on field structures can be distinguished from
dirt with bleach. Common household hypochlorite bleach will
cause mildew, but not dirt, to whiten.
5.20
Pavement Markings. Asphalt and concrete airfield and
road pavements on military bases are generally striped with paint
to show center and sidelines, as well as other information.
These markings are described in NFGS-02761, Pavement Markings,
and CEGS 02580, Joint Sealing in Concrete Pavements for Roads and
Airfields.
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