EN 351-1:2022

Durability of wood and wood-based products - Preservative-treated solid wood - Part 1: Classification of preservative penetration and retention

General information

60.55 Ratification completed (DOR)   Jul 17, 2022


CEN/TC 38 Durability of wood and wood-based products

European Norm

71.100.50   Wood-protecting chemicals | 79.040   Wood, sawlogs and sawn timber


This part of EN 351 establishes a classification of preservative-treated wood in terms of preservative penetration and gives guidance on a classification of retention. These shall be used as a basis for specifying preservative treatments for particular products.
This part of EN 351 provides terminology to be used by the specifier when preparing a preservative treatment specification or product standard. It is not a treatment specification in itself.
This part of EN 351 is applicable to the production of preservative-treated solid wood, including glued laminated timber, suitable for use in those service conditions defined by the use classes in EN 335. It does not apply to any subsequent examination of treated wood in service.
This part of EN 351 is applicable to the protection of wood against attack by wood-destroying and wood-disfiguring fungi, insects and marine organisms.
NOTE Protection against wood-disfiguring fungi is an optional property verified by testing in accordance with EN 599-1.
This part of EN 351 does not consider other properties of treated wood, for example odour, compatibility with other materials, such as corrosivity of fasteners. Nor does it consider any properties from the health, safety and environmental point of view.
This part of EN 351 does not apply to wood to be treated with formulations which are applied to timber in service to eliminate or control an existing fungal or insect infestation, or the prevention of attack by sapstain fungi, or insects in green timber.
Annex A (informatives) provides a decision process for defining preservative treatment requirements.
Annex B (informative) gives an example of the marking system.

Related legislation

Legislation related to this standard


Regulation (eu) No 305/2011 of the European Parliament and of the Council of 9 march 2011 laying down harmonised conditions for the marketing of construction products and repealing council directive 89/106/eec

Life cycle


EN 351-1:2007


EN 351-1:2022
60.55 Ratification completed (DOR)
Jul 17, 2022