Right to use the NTR mark

Manufacturers with a valid certificate are entitled and obliged to label their wood products with the NTR mark and wood protection class in accordance with what is stated in the NTR documents.

The NTR mark is a registered trademark of the Nordic Wood Preservation Council, NWPC.

Violation and abuse of the right to label will be counteracted and may lead to exclusion. Businesses that have lost their labelling rights can be found in the table of revoked licenses.

Producers affiliated to third party quality control have the right and obligation to brand the products with the NTR quality marks.

All products have to be marked in accordance with the NTR documents.


Marking must be done either as bundle marking or through branding each item. In case of NTR class A and NTR A pole each item must be individually marked.

Individual marking is done directly on the treated item with the NTR quality mark or alternatively by colour code on the end grain.

Exception from these requirements is permitted. Note. Examples are fence posts and sleepers.

Bundle marking shall at least contain the following information:

  • Treatment according to NTR Document No 1, Part 1, and EN 351-1
  • Name of wood preservative used and active ingredients declaring it is a biocidal product;
  • Wood protection class and penetration class according to EN 351-1: NP 5 for classes NTR M, NTR A, NTR A pole and NTR AB, NP 3 for class NTR B
  • Intended end use(s) for the treated wood
  • Against which wood destroying organisms protection is given
  • Wood preservative retention (refer to NWPC list of approved wood preservatives)
  • Charge number of production
  • Name and contact details of the producer

The quality marks may also be used on invoices, letterheads, promotion leaflets etc.

Delivery documentation (e.g. delivery note) shall always contain information on the wood preservative used and wood protection class. If pre-printed on invoices, delivery notes etc. that the wood delivered is treated according to the requirements in NTR Document No 1, Part 1, it must be clearly stated if the wood is treated according to another specification to avoid misunderstanding.

Producers treating wood according to NTR Document No 1, Part 1, and certified for CE-marking may also use the CE-mark to mark each item, or for bundle marking.

by | 2021-11-16

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