Wood preservatives and slimicides during the transitional period

Wood preservatives and slimicides are products used for:


  • the protection of wood from deterioration or damage caused by harmful organisms (such as moulds, fungi or insects) or
  • the prevention or control of slime growth in industrial processes, e.g. on wood and paper pulp.


Manufacturers and importers of wood preservatives and slimicides must obtain Tukes's authorisation before they can begin the manufacturing, import or placing on the market of such products. The authorisation applies to chemicals used for the above-mentioned purposes, regardless of how hazardous they may or may not be. 


The marketing of wood preservatives and slimicides is subject to special regulations concerning biocidal products.


Authorisation procedure

Authorisation can be requested for products with an active substance that has been notified for evaluation in the review programme of biocidal active substances and that is not found in the Commission's list of active substances on which a non-inclusion decision has been taken. After the transitional period the authorisation of wood preservatives and slimicides will in all respects take place under the Community authorisation procedure. The transitional period is due to extend until 31 December 2024 but it may also be shorter, ending once a decision concerning the acceptability of the active substance the product contains has been made in accordance with the Biocidal Products Directive or Regulation.


To learn more about the key issues in the authorisation procedure see the Application Guide.


Wood preservatives and slimicides that have not been issued with an authorisation may be manufactured for export or subjected to experiments or tests but, under the Chemicals Act, Tukes must also be informed of these.



Each application must be accompanied by a dossier of information regarding the product and its active substances. Provisions regarding the information required are laid down in the Ministry of the Environment decision 419/2014.


Application documentation can be in Finnish, Swedish or English. The completed application form with appendices must be submitted to Tukes. Instructions for use and other package labelling and the safety data sheet must be provided in Finnish and Swedish. Applications for renewal must be made one year prior to the expiry date of the valid authorisation.


Authorisation fee

Tukes will charge a fee to cover the processing of each application.



Details of authorised wood preservatives and slimicides are filed in a list (in Finnish).


Questionnaire on quantities sold

Manufacturers or importers of wood preservatives and slimicides must, on request, provide Tukes with annual information about the amounts of chemicals manufactured and imported by them (Chemicals Act 599/2013, 22§).  The form should be filled in by March 31st.