Specifies requirements for penetration and retention of a range of preservatives for sawn and round timber for use in conditions where the material is exposed to decay, insect and marine borer attack hazards. This Standard does not apply to plywood and veneer timber. The composition of acceptable preservatives are given, and recommended treatments and levels are listed according to the anticipated exposure conditions. Appendices give information on hardwood not susceptible to lyctid attack, hazard classifications for various applications and the natural durability of commercial timbers.