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 CHAPTER 6. QUALITY MANAGEMENT
The two essential components of a comprehensive quality management program are: (1) procure-
ment specifications that accurately define products which will have an acceptable life expectancy
and reasonable cost and (2) adequate inspections to verify compliance with those specifications.
Therefore, to ensure quality, team effort is needed between procurement personnel and personnel
who receive/inspect materials at points of destination.
Preparation of a procurement document which accurately identifies the type and quality of wood
material, the type of wood preservative, and the preservative treatment requirements is the first
step in obtaining treated wood products suitable for the intended end use. This is usually ac-
complished by referencing appropriate consensus standards (Chapter 5) or federal standards
(Chapter 5) that address both the required material properties of the wood product prior to treat-
ment and the quality of the preservative and treatment process applied to the wood.
The second step in assuring quality in treated wood products is an independent inspection of
materials for conformance of both materials and treatments with the procurement specifications.
Materials are inspected for compliance "in the white" within 10 days prior to treatment. Inspec-
tions for compliance with treating specifications may be performed at the plant (preferable) and/or
at the point of destination.
6.1 PROCUREMENT SPECIFICATIONS. Specifications exist which define the quality of the
wood product to be treated, the preservatives to be used, and for the treatment procedure itself.
This section will discuss these specifications in detail.
6.1.1 Material Specifications. Material specifications describe the amount of acceptable
natural variation in wood properties and identify those natural features (defects) which are not ac-
ceptable. Inspection is generally done prior to treatment, i.e., "in the white".
6.1.1.1 Natural Variability. Since wood is a natural material, material standards,
are especially important because the material is characterized by a wide range of variability. How-
ever, through a prescribed selection process, wood products with known structural properties and
engineering design values are produced.
The engineering design values for wood take into consideration, within limits, the natural strength
variations of wood. As described in Chapter 2, the growth rate of wood can affect its strength
properties. For example, the American National Standards Institute (ANSI) specifies the mini-
mum number of annual rings which can be accepted in the outer butt portion of poles. The re-
quirement for not less than six annual rings per inch (or four or five rings per inch if 50% or more
summerwood is present) helps assure the buyer that poles meeting these material standards should
have the strength properties used in the engineering design requirements.
6-1
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