3.1.1.3
Paint Stripping
Brush or spray on a paint stripping material that has been demonstrated to
effectively remove the paint. Leave the stripping material on the surface
until the paint has softened or blistered. Remove paint by scraping,
brushing, or wiping. Rinse the surface in accordance with the stripping
material manufacturer's recommendations. Avoid strippers containing toxic
methylene chloride.
3.1.1.4
Acid Etching
Apply a 10 percent solution of muriatic acid at a rate of one liter per
square meter one quart per each 10 square feet of concrete surface. Allow
the solution to stand until it stops bubbling but not less than 5 minutes.
Remove the acid and wash the surfaces several times, as required, to remove
all traces of the acid. Always dilute acid by pouring into water. Use
face shield rubber gloves, and other safety equipment when using acids,
3.1.1.5
Air Drying
After cleaning, allow concrete surface to air dry thoroughly prior to
application of surfacing. Blowers or oil free compressed air may be used.
Do not use flame-drying methods. Prior to application of surfacing, test
concrete surface for excessive moisture in at least two locations. Place
rubber mats at each location with smooth side against concrete and place
weight on top of mat to hold in position and ensure contact with concrete.
Polyethylene with all edges taped may be used in lieu of mats. After 8
hours remove mat or sheeting and examine floor surface for moisture
accumulation. If tests indicate accumulation of moisture at either
location, additional air drying shall be undertaken until additional tests
show no moisture accumulation.
3.1.2
Plywood
New plywood substrates shall be exterior grade plywood with exterior grade
glue and nailed with annular ring or spiral nails. Sand the plywood to
remove all latent contaminants. Sweep or vacuum surfaces to remove all
sanding debris. Tape joints with 100 mm 4 inch wide glass fiber reinforced
tape.
3.1.3
Ceramic Tile
Remove all fats, oils, grease, or soap scum using a caustic solution of one
kg one pound of caustic soda to 8.3 L one gallon of water. Allow the
solution to stand on the surface for at least one hour then scrub with
steel brushes or steel wool. Mop up the caustic solution, neutralize it
with a 10 percent muriatic acid solution, and thoroughly rinse the residue
from the surface. Glazed tile shall be treated with a deglazing agent as
recommended by the flooring manufacturer and sanded or acid etched to
roughen the surface sufficiently to obtain a good bond. Sweep or vacuum
surfaces to remove all sanding debris. Use face shield, rubber gloves, and
other safety equipment when using acids, alkalies, or solvents.
3.1.4
Filling Cracks, Spalls, Joints, and Other Depressions
Fill all cracks, joints, spalls, and other depressions in the substrate
with a latex underlayment, as recommended by the manufacturer compatible
SECTION 09670
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