FACT: Co-normative research on field tests for wood preservatives out of ground contact in conjunction with methods for preconditioning test specimens prior to test

• Research unit: EU RFP
• Project number: 96.0045

Key words (English)

Ageing; artificial weathering; conditioning; biocide; degradation; fungi; insects; preservation; standard; UVS-cabinet; wood

Alternative project number (English)

EU project number: SMT4-CT96-2135

Research programs (English)

EU-programme: 4. Frame Research Programme - 2.2 Measurements and testing

Short description (English)

See abstract

Further information (English)

Full name of research-institution/enterprise:
Eidg. Materialprüfungs- und Forschungsanstalt EMPA
Abteilung Biologie

Partners and International Organizations (English)

Coordinator: Imperial College of Science London (UK)

Abstract (English)

The aim of the project was to deliver to CEN/TC 38 a series of recommendations for draft standards with procedures for accelerated ageing of treated wood. This should allow to shorten the development time of wood preservatives. 15 partners from 9 countries participated in this project. EMPA has been charged, in this relation, with the co-ordination of the research work within Core Task 1 'Ageing Meth-ods for Surface Treated Wood', involving 6 partners. The object of this part project was to develop a draft standard for the artificial weathering destined to be applied for European hazard classes (EHC) 1-3, prior to the biotest.
Within Core Task 1 the research focused especially on surface treated wood in hazard class 2 (without and with construction phase) and in hazard class 3. Different UVS artificial weathering cycles have be-en compared with natural weathering in the field and with the existing reference standards EN 73 (evaporation) and EN 84 (leaching).
Compared to a 90° inclination of the exposed wood samples in the field, an inclination of 45° accelera-ted the ageing of treated wood up to factor 2. Tests with insecticides and fungicides according to the existing standards EN 73 and EN 84 are appropriate to simulate climatic conditions in EHC's 1 (with construction phase), 2 and 3. No draft standard can be presented to CEN/TC 38, since the period of the project was too short for the biotests with wood destroying fungi and insects. Both, the UVS artificial weathering procedures of EMPA SG and of BAM, can be taken as a good basis for further development of a standard. The test duration of the EMPA procedure is reduced of approx. 50% in comparison with the BAM procedure. The development of a draft standard for artificial weathering can be accelerated and the cost-performance for research reduced, if the required number of weathering cycles on the de-gradation of the different active ingredients (A.i.) and formulations on treated pine wood is evaluated first with chemical analyses. Validation by biotests is required before a recommendation with deter-mined weathering cycles can be given to CEN/TC 38 for a draft standard.
It is of particular importance for Switzerland that on spruce a natural and artificial ageing reduce the ef-ficacy of the biocidal surface treatment more than on pine, as a lower biocide penetration for spruce is obtained.

References in databases (English)

Swiss Database: Euro-DB of the
State Secretariat for Education and Research
Hallwylstrasse 4
CH-3003 Berne, Switzerland
Tel. [phone]
Swiss Project-Number: 96.0045