This European Standard specifies general requirements for structural timber that has been treated with preservatives against biological attack. This European Standard also specifies requirements for the evaluation of conformity and marking of preservative treated timber products when they are placed on the market. Treatments, which include a biocide, are covered by this standard. It does not provide details of which preservative treatments are necessary for a particular type of structural timber product to achieve a required service life, as regional climatic differences and prevalent biological agents would need to be taken into account for that purpose. This European Standard does not cover any subsequent treatment which may be required for structural timber products which have been machined, bored or planed after the CE marking has been applied. This standard does not cover the qualification of preservation products used to treat structural timber.