The National Wood Window and Door Association specifies acceptable preservatives and the de-
gree of water repellency required for non pressure treatments.
"Treatment to refusal" is the terminology still used in standards for pressure treatment of a few
very difficult to treat woods, such as white oak. When this terminology is used in a procurement
specification for pressure-treated products, it does not require a minimum amount of preservative
(retention) nor does it require a minimum depth of treatment (penetration). Whenever the mini-
mum retention and penetration are listed in standards for pressure-treated wood products, this ter-
minology, "treatment to refusal," should not be used. Instead, cite the standard as published. Use
of the terminology, "treatment to refusal," could allow acceptance of poorly treated products that
would not otherwise meet standard requirements.
220.127.116.11 Examples of Treatment Specifications. The consensus standards of the
American Wood Preservers Association, P.O. Box 849, Stevensville, MD 21666, address pressure
treatments and other treatment technologies which contribute to the penetration and retention of
the preservative in the wood. The purpose of using AWPA standards is to ensure that wood
products are treated with suitable preservatives for reasons of safety, service, and savings resulting
from unnecessary, expensive and premature replacements.
The National Wood Window and Door Association Industry Standard for Water-Repellent Pre-
servative Treatment for Millwork I.S.4. covers requirements for water-repellent preservative for-
mulations for wood. For purposes of this standard, millwork includes exterior products such as
prefit wood windows, sashes, screens, window frames, blinds, shutters, wood doors (except flush
doors), door jambs, cut-to-length trim, and machined knocked-down parts of those products.
The U.S. General Services Administration (GSA) standard for Wood Preservation covers the treat-
ment of different forms and species of wood with various preservatives. Standard requirements
are attainable by pressure processes, as well as, by several other processes.
The GSA specification for Wood Preservative: Water-Repellent TT-W-572B covers materials that
combine water-repellent and preservative properties of ready-to-use solutions for treatment of
wood by simple non-pressure methods.
18.104.22.168 Unique DOD Needs. Sometimes, unique DOD needs require a more
precise definition of preservative treatments than is given in standards generally accepted in the in-
dustry or federal specifications which are broadly based to encompass the total U.S. wood preserva-
tion industry. These needs can most easily be met in procurement specifications by identifying
exceptions or additions to existing standards or federal specifications. Attempts to independently
write new requirements could easily commit errors by omitting some of the complex considera-
tions of wood species, commodity, and treatment interactions that have been addressed in estab-
22.214.171.124 Inspection Requirements. To insure compliance by the supplier, with
procurement orders, shipments must be inspected. It is U.S. Navy policy to obtain independent in-