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 tended for use in marine exposure or foundations. Control over wood temperature is essential in treating
wood with waterborne preservatives containing chromates which are. unstable in contact with wood at
high temperatures.
3.4 Seasoning. Green material shall be adequately seasoned or conditioned before impregnation
with preservative. This practice applies particularly to sawn material that is difficult to penetrate and to
round material of thin sapwood species. All sawn material that is to be treated with an oil-type preserv-
ative and used in buildings or other places where high-moisture content or shrinkage after installation
would be objectionable shall be dried before treatment. When sawn material is treated with a permanent-
type, chromium-containing preservative, such as chromated copper arsenate, the moisture content prior
to treatment as determined by resistance-type moisture meter, shall not be more than 25 percent. The
moisture content shall be measured at a depth equivalent to the required penetration up to a maximum of
1.5 inches. When treated with other waterborne preservatives, sawn material shall be suitably seasoned
or conditioned prior to treatment. Unless otherwise specified (see 6.2), lumber 2 inches (nominal) or
less in thickness and plywood that is treated with a waterborne preservative shall be dried after treatment
to a moisture content of not more than 19 percent.
3.5 Incising. All lumber and timbers of species that are difficult to penetrate, such as Douglas-fir,
Western larch, western hemlock, redwood, and pines that are predominantly heartwood, shall be incised
prior to treatment, provided the incisions will not make the material unfit for the use intended.
3.6 Marking. Unless otherwise specified (see 6.2), treated material shall be either hammer or heat
branded, dye stamped, or metal tagged in accordance with AWPA Standards M1 and M6. Information
shall be included for specific commodities, as given in the following:
3.6.1 Poles 50 feet or less in length shall be branded or tagged 10 feet from the butt. Poles 55
feet or more in length shall be branded or tagged 14 feet from the butt. All poles shall have the required
branding or tagging included on the butt face. The brand shall identify species, class and length, preserv-
ative, retention, supplier, and year of treatment.
3.6.2 Piles shall be branded or tagged in two places approximately 5 and 10 feet from the butt.
The brand shall identify species, class and length, preservative, retention, supplier, and year of treatment.
3.6.3 Posts shall be branded or tagged at or within 12 inches of the top. The brand shall identify
preservative, supplier, and year of treatment.
3.6.4 Crossties shall be branded at least on one end. The brand shall identify preservative,
supplier, and year of treatment.
3.6.5 Crossarms shall be branded on one face. The brand shall identify preservative, supplier,
and year of treatment.
3.6.6 Sawn material more than 2 inches (nominal) in thickness and treated with an oil-type
preservative shall be individually branded or tagged on one end to identify species, preservative, reten-
tion, supplier, and year of treatment. When treated with a waterborne preservative, it may be dye
stamped on the surface.
B-5
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