Quality Assurance

By: Western Wood Products Association  06-Dec-2011
Keywords: Lumber, Mills, Quality Standards

WWPA is the leader in the West in lumber grading, rules writing and quality control inspection.

Lumber grading rules are a set of criteria used to determine how various characteristics, such as wane or knots, affect the structural performance of dimension lumber or the aesthetic value of appearance grades. Lumber manufacturers are responsible for grading the lumber to these rules and WWPA, as part of the American Lumber Standards system, helps assure that Western lumber meet stated product quality standards.

Association Quality Assurance activities include:

  • Lumber inspection and grade rules writing. WWPA is one of seven grading agencies in North America authorized to write and publish grading rules for lumber. The Association also conducts regular inspections at mills to assure consistent quality between mills. Each year, WWPA lumber inspectors check lumber representing┬ásome 10┬ábillion board feet of production.

  • Grade certification. Lumber carrying the WWPA grade stamp is backed by a host of quality standards services offered through the Association. For example, WWPA mills can provide Inspection Certificates which attest the lumber certified meets specifications. The Association provides special export certificates on lumber shipped to foreign ports, as well as certification for Japanese Agricultural Service, or JAS, grading. When disputes between a mill and the customer on a shipment of lumber, WWPA can act as an impartial third party and will reinspect the lumber to determine if it meets the invoiced specifications.

  • Special products. WWPA is one of the largest providers of quality control services for glued lumber and machine stress-rated (MSR) lumber. The Association pioneered the quality control procedures used by the lumber industry to make MSR products, and WWPA provides quality control for more finger-jointed lumber operations than any other lumber grading agency in North America.

Keywords: Lumber, Lumber Grading, Lumber Inspection, Lumber Inspectors, Lumber Manufacturers, Mills, Quality Standards,

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