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1. What is CCA and how does it work?
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The chemical used to preserve Wolmanized Heavy Duty pressure-treated wood is a mixture
of the oxides of copper, chromium, and arsenate known as CCA. The preservative has
been formulated to render wood useless as a food substance for termites and fungi while keeping the wood attractive, clean, odorless, non-staining, and safe to handle
when used as recommended. For more information, please click here.
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2. For what applications can Wolmanized Heavy Duty wood be used?
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Wolmanized Heavy Duty
wood can be used for industrial applications. For listed uses,
please click here.
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3. What are AWPA retention requirements & Use Categories?
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Wolmanized Heavy Duty
pressure-treated wood is treated to various retention levels that are intended to
protect the wood for particular applications. Retention levels indicate the amount
of preservative retained in the wood in a specific assay zone. For more information,
please click here.
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4. What hardware is recommended for Wolmanized Heavy Duty wood?
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Corrosion-resistant fasteners should be used with Wolmanized Heavy Duty
wood. For detailed information, please click here.
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5. What are the design values for CCA-treated wood? |
Since pressure treatment with Wolman® CCA preservative does
not alter the natural characteristics of wood, the design values for untreated lumber
and plywood should be used in accordance with the National Design Specification
for Wood Construction (2001 edition), issued by the American Forest and Paper Association.
Wood products which
have been preservative-treated are referenced in Section 4.3.14
and 6.1.4. If lumber is not dried after treatment, or if the end use will result
in a moisture content exceeding 19%, wet service factors shall be applied (see 4.1.4
and 4.3.3).
In addition, load duration factors greater that 1.6 shall not apply
to structural members. The design values for all acceptable species and grades of
lumber are given in the Supplement to the National Design Specification.
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6. Is CCA-treated wood safe? |
The fixation which occurs subsequent to the treating
process makes Wolmanized Heavy Duty wood safe for the environment and for the individual
user when this wood is handled as recommended. Once the Wolman CCA is fixed in the
wood cells, it is highly leach-resistant. With seven decades of usage, its harmlessness
to people, plants, pets and the environment has been documented by academic and
governmental researchers and agencies.
As a federally registered pesticide, Wolman
CCA preservative undergoes a formal investigation and evaluation by the Environmental
Protection Agency periodically. Based on an abundance of documentary evidence, the
EPA deems Wolmanized® wood to be suitable for uses described on this site (see Consumer
Safety Information Sheet). Other agencies also oversee aspects of the production,
transportation, and use of CCA and CCA-treated wood. Material Safety Data Sheets
are available from the treating companies licensed to manufacture Wolmanized Heavy
Duty wood.
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7. What are the environmental benefits of Wolmanized Heavy Duty wood? |
Unlike plastics, steel, and concrete, Wolmanized wood is made from a renewable resource
grown on managed timberlands. It requires less energy to produce than plastics and
offers greater insulation value; and, because of its lighter weight, preserved wood
can often be installed with lighter equipment which has less environmental impact.
Wolmanized Heavy Duty wood also contains copper derived from recycled sources. For
more information, click here.
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8 How is Wolmanized Heavy Duty wood produced? |
The
basic treating process is simple and highly controlled.
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Lumber, timbers, or
plywood is loaded onto small rail or tram cars. The trams are moved into a large,
horizontal treating cylinder.
- The cylinder door is sealed and a vacuum is applied
to remove air from the cylinder and the wood cells.
- Preservative solution is
then pumped into the cylinder.
- The pressure is raised to about 150 pounds per
square inch, forcing CCA into the wood. Treating time varies depending on species
of wood, commodity being treated, and the amount of preservative to be impregnated.
- At the end of the process, excess treating solution is pumped out of the cylinder
and back to a storage tank for later re-use.
- A final vacuum removes excess preservative
from wood cells. The cylinder door is opened and the trams are pulled out. The wood
is wet, so it is kept on a concrete pad until any dripping ceases.
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