Footnotes for Tables I, II, and III
Whenever a method for the determination of retention in a treated product by the assay of a
sample is described in an AWPA specification, purchase shall be made on that basis and a retention
gage shall not be accepted in competitive bids.
These standards cover treatment of species most commonly treated. For species offered and not
covered by existing standards; the supplier shall furnish evidence of satisfactory experience. Penetration
requirements for most generally available products are covered in AWA specifications and footnotes
below. When penetration is not otherwise specified herein or in AWPA specifications, the penetration
in the sapwood shall be not less than 2.5 inches unless 85 percent of the sapwood depth is penetrated
(see footnote 11). For wood species not included herein or in AWPA specifications, the penetration of
heartwood faces shall be not less that 0.4 inch in lumber (i.e., sawn material less than 5 in. in thickness)
and not less than 0.5 inch in timbers (i.e., sawn material 5 in. or more in thickness). Retention shall be
consistent with end use of the product.
Conforming to class 3 of TT-C-645.
Conforming to class 5 of TT-C-650.
Conforming to either class 1, 2, or 3 of TT-C-645.
Conforming to either class 1, 2, 3, 4, or 5 of TT-C-650.
For ground contact use: For members more than 75 square inches in cross section at the
groundline, every member shall be bored for penetration. For members 75 square inches or less in cross
section at the groundline, 20 members per charge shall be bored for penetration. Should the charge con-
tain less than 20 members, each member shall be bored. When inspecting southern yellow pine
laminated timbers for penetration, borings shall be taken from two different laminations from each mem-
ber. When boring Coastal Douglas-fir or western hemlock laminated timbers for penetration, one boring
shall be taken from the edge of the two face laminations and one boring from each of two different inte-
rior laminations in each member.
If any boring taken from any member fails to meet the penetration requirement, that member
shall be rejected. If 90 percent or more of the members bored meet the specified requirements for either
size category, the charge shall be considered to meet penetration requirements. If less than 90 percent of
the members bored meet the specified requirements for either size category, the charge shall be rejected.
For above ground use. One boring shall be taken from each of 20 members in a charge. If 80
percent or more of the borings show a penetration of 2.5 inches or 85 percent of the sapwood in
southern and ponderosa pine or 0.50 inch in the heartwood of coastal Douglas-fir or western hemlock,
the charge shall be considered to meet penetration requirements. Should a charge contain less than 20
members, each member shall be bored and any member shall be rejected if it fails to meet the penetra-
tion described in the foregoing.