This Standard specifies a method of test for wood preservatives that are intended for use in wood to be exposed to the weather out of contact with the ground without the additional protection of a surface coating (i.e. Use Category 3). The method should be used in situations where the AWPA Standard E9, a method of test for wood preservatives applied in combination with a coating, is not applicable.

The main objective of the method is to evaluate the relative effectiveness of the preservative, applied to jointed samples of pine sapwood by a treatment method relevant to its intended practical use. Effectiveness is evaluated relative to a reference preservative treatment. The method is concerned with the protection against decay after exposure to the complete range of micro-organisms occurring under natural conditions. It also takes into account physico-chemical effects of weathering on the performance of the preservative treated wood.