The effect of artificial ageing on the durability of wood-based board materials against basidiomycete decay fungi

In the biological testing of wood based board materials it has been demonst rated that the exposure of boards in a closed vessel system may lead to ina ccurate results due to the build-up of volatile substances that inhibit the test fungi. It is assumed that this is a transitory effect of freshly manu factured boards. Our results with the European standard for testing the fun gal durability of board materials, which is currently under development (EN V 12038:1996), confirm that this inhibition has a significant effect on the reliability of the durability results obtained. In the standard, a leachin g procedure is used as part of a preconditioning method to remove this effe ct. Several factors suggest that leaching may not be the most appropriate m ethod for this task. Therefore, a variety of alternative ageing procedures were studied, including natural weathering, leaching and evaporative proced ures, to determine the most appropriate preconditioning protocol for the de cay test. The results show that non leaching procedures can be more efficie nt, and possibly more meaningful, than leaching for use on board specimens.