This document gives guidance on the selection of wood of wood and wood based products for use in situations where they may be subject to degradation by fungi or wood destroying insects. This guidance includes information on factors that can influence the service life of a wood or wood-based product when considering biological degradation. This document is a step toward the evaluation of the service life of a wood product. This document does not consider: 1) the durability characteristics of the glue used in wood-based products; 2) the aesthetic function of wood products (discoloration, surface weathering, mould).