Wood failure is one of the principal means for determining the quality of an adhesively bonded wood joint.

When evaluated after a water soaking, water soaking and drying, or boiling and drying, the percentage of wood failure is an important criterion for qualifying adhesives for use in plywood and glued laminated structural timber for exterior use, and for daily quality control of the processes for manufacturing plywood and glued, laminated timbers. Standards that use the percentage of wood failure are included in Section 2.

In plywood manufactured from North American softwood species, the percentage of wood failure of Test Method D 906 specimens, tested wet after either a vacuum-pressure soak-dry or boil-dry treatment, correlates with the percentage of panels that delaminate in outdoor exposure without protection.⁸

Similar correlations for other products have not been published.

1.1 This practice provides procedures for estimating the percentage of wood failure that occurs in plywood-shear, block-shear, finger joint test specimens, or any other bondline involving wood.

1.2 The values stated in SI units are to be regarded as the standard. The values in parentheses are provided for information only.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.