IRG Documents Database and Compendium


Search and Download IRG Documents:



Between and , sort by


Displaying your search results

Your search resulted in 116 documents. Displaying 25 entries per page.


Climate indices at work: Above ground decay L-joint tests (EN 330 and AWPA E9) at two sites 12000 km apart and with Scheffer climate indices of 60-65 and 300-330
1996 - IRG/WP 96-20095
Matched sets of Scots pine sapwood (Pinus sylvestris) L-joints were exposed above ground at two field sites for approximately five years. One site, at Garston, Watford, UK has a climate index between 60 and 65 while the other, close to Hilo, HI, USA has an index between 300 and 330. The joints were treated with a range of organic solvent treatments applied either by three minute dip immersion or by double vacuum. Untreated joints were installed at each site as control material. All samples were assessed at approximately annual intervals at both sites. After five years, decay at the Hilo site is well advanced with failure apparent in many joints, both untreated and treated. As would be expected given the climatic differences, decay at the Garston site has progressed more slowly than in Hilo. Differentiation in treatment performance was apparent after one year's exposure in Hilo with similar differentiation becoming apparent after five years' exposure in Garston. This acceleration correlates well with the difference in Climate Index for the two sites as calculated using the Scheffer method. Encouragingly, the performance ranking of the different treatments at the two sites was very similar. The results of this test suggest that the concept of using high decay hazard sites for field testing of treated wood products for use in above ground situations can provide meaningful results in a short period, and may offer a timely and realistic alternative to relative preservative testing to that achieved in laboratory test regimes. The results also show that above ground field testing at both of the sites included provide valuable information on preservative performance, and this information is likely to provide a greater degree of realism than is possible using pure culture laboratory test procedures.
A F Preston, K J Archer, D M Roberts, J K Carey, A F Bravery


A new concept for the evaluation of wood durability for out of ground contact using accelerated L-joint testing
1997 - IRG/WP 97-20123
Since the wood preservation sector is developing in favour of defining exactly the utilization of wood products and preservation techniques as a function of the envisaged hazard class, more in particular the hazard classes 3 and 4 (EN 350) there is obviously a need for a test method evaluating natural durability for out of ground contact applications. Based on the L-joint test as described in the European standard EN 330 a test method is under evaluation to determine the out of ground contact durability of various temperate and tropical wood species. Major parameters in the accelerated L-joint durability test are: the open joint structure, an exposure with 10° inclination facing sout west, tenon members in a 50/50 beech - Scots pine sapwood combination and a controlled drip irrigation system in the joint corner. This new concept is independent of specific coating systems and minimizes the variability in testing due to long dry periods under certain climatic conditions.
J Van Acker, M Stevens


Visual Inspection – How Important is the Influence of the Evaluator?
2013 - IRG/WP 13-20521
Visual inspection is often a crucial means of judging the efficacy and performance of a preservative. It is used in non-destructive testing in long term exposure trials or simply, when the practical use and precision of the human eye is a good means of measure. As for the procedure described in EN 252, the impression of softness due to decay of the wood has also to be considered. Although, a thumb and an eye are unequivocally refined sensors, there is no method published for their calibration according to the method they are used in. So, quality assurance of visual inspection is often neglected. This paper proposes a procedure that may lead to constructive discussion and harmonisation of the interpretation of rating scales among evaluators. It is based on the experience of European countries within the Nordic Wood Preservation Council (NWPC) and CEN/TC38 WG 25 working on the clarification and correct interpretation of rating scales as in EN 252. During three workshops, practical work was performed on wood stakes from the field showing different levels of attack by fungi. In average all evaluators agreed on the evaluation in 21% of the cases, while at least one evaluator disagreed in 67%. In 12% of the cases the stake was given three different ratings. A following discussion led, in almost every case, to agreement on a rating class according to EN 252. We suggest that especially accredited laboratories that perform this type of testing regularly participate in such workshops to "calibrate" themselves with their colleagues and the intention of the standards. A procedure, as described in this paper, for performing quality improvement of the evaluation according to the rating scale could be useful as an informative annex in all standards where visual inspection is used, e.g. EN 252, EN 330 and CEN/TC 12037.
M Klamer, P Larsson Brelid, I Stephan


Comité International Permanent pour la Recherche sur la Préservation des Matériaux en Milieu Marin. Information from the Wood Group
1980 - IRG/WP 460
E G B Jones


Insect resistance of preservative treated tropical plywood against Lyctus
1990 - IRG/WP 1453
Seven plywood types composed of tropical wood species, vulnerable to Lyctus, were treated with various commercial water-borne and oil-borne preservatives. A wide range of preservative retentions was obtained by treating boards with dip treatment, steeping, double-vacuum and vacuum-pressure impregnations. Selected samples were subsequently tested for their insect resistance against Lyctus africanus during 6 to 8 months according to European Standard EN 20. All control samples were attacked, except one Obeche plywood exhibiting only 50% attack. Water-borne preservative solutions containing arsenic, boron or fluoride could not prevent attack at common retention levels for interior use e.g. lower than 5 kg/m³. Quaternary ammonium compounds showed no insecticidal efficiency, up to 3 kg/m³. TCMTB at 1.5-1.7 kg/m³ proved to be able to reduce slightly the susceptibility for insect attack. Organic insecticides gave the best results, with nearly no attack for plywood treated with lindane or cypermethrin. In spite of a preservative uptake of 25 to 30 kg/m³, endosulfan only could reduce attack by 50%. Protection by permethrin at 0.1% a.i. required a retention of 28 kg/m³. Besides the fact that variability in wood species and composition of the plywood are leading to different retention levels, variation in penetration and distribution of a.i., and as a consequence to a different insect resistance of the impregnated boards, some poor results were directly related to inadequate insecticidal activity and/or concentration of a.i. in some commercial formulations for Lyctus control.
J Van Acker, M Stevens, M Pallaske


Studies on accelerated ageing procedures with TBTO-treated wood
1985 - IRG/WP 2244
The efficacy of various procedures for accelerated ageing of organotin based wood preservatives in treated wood has been investigated. It was found that leaching of the treated wood samples in water according to the European Standard EN 84 was not satisfactory for organotin based preservatives and is probably also unsuitable even for other types of organic solvent preservatives. Keeping tributyltin oxide (TBTO) treated samples in a heating cabinet at 70°C for five weeks, however, had a considerable effect on the breakdown of TBTO and the subsequent decay test. Therefore, an ageing procedure involving a heating period should be considered for all organic solvent wood preservatives. The investigation also confirmed that elevated temperatures accelerate the degradation of TBTO and that there is a strong correlation between the percentage of TBTO in the wood and its resistance against decay.
J Jermer, M-L Edlund, B Henningsson, W Hintze


Interspecific variability of European oak durability against white rot fungi (Coriolus versicolor): Comparison between sessile oak and peduncle oak (Quercus petraea and Quercus robur)
2001 - IRG/WP 01-10393
The knowledge of wood natural durability against biologic predators enable its external use. The resistance of European oak wood was reported like durable according to the EN 350-2. However, some individuals may contain high durable wood. Our research was focused to understand this variability in oak population that represent the first french species (4.1 millions of ha). Natural durability of European oak heartwood (Quercus petraea and Quercus robur) against white rot fungi (Coriolus versicolor) was tested according to european standard EN 113. The experimental material consists in 23 oaks robur and 26 petraea oaks sampled from 9 French regions. For each tree, 3 twin samples were taken off from heartwood situated at 1.30 m from the bottom of the tree. Different effects were tested by hierarchic variance analysis: "species", "forest within species" and "tree within forest". The tree effect is very significant for biologic natural resistance. Variability between species was also demonstrated. Although the species effect is significant, it's relatively weak compared with tree differences (it was declared significant 5%). Durability classification was determined according European standard EN 350-1. 69.2% of petraea oak trees are classified as high durable, 19.2% durable, 7.7% moderately durable and 3.8% slightly durable. In the case of robur oak 91.3% of trees are classified as high durable and 8.7% durable.
N Ayadi, B Charrier, M Irmouli, J P Charpentier, C J Allemand, F Feuillat, R Keller


Temperature influence on the growing velocity and cellulolytic activities of Poria placenta strains from several locations
1986 - IRG/WP 2263
The differences observed on the FPRL 280 Poria Placenta strain at several Research European Laboratories for determining up the fungicide effectiveness of wood preservative has carry us to do a comparative study about the cellulolytic activity and growth velocity of each of this strains at different temperatures (22, 24 and 28°C). The results show significative differences when the temperature is changed.
A M Navarrete, M T De Troya


Possibility of use of wood species per class of biological risks. Attempt to determine criteria based on Pr EN 350-1/2/3
1992 - IRG/WP 92-2409
M Rayzal


Rapport sur l'activité du CEN/TC 38
1983 - IRG/WP 2204
M Pottevin


Depletion of boron and copper from CCB treated test specimens using different leaching protocols
2004 - IRG/WP 04-50208
The objective of this study was to measure the depletion of inorganic wood preservative components regarding the proposed OECD guideline "Estimation of emissions from preservative-treated wood to the environment: laboratory method for wooden commodities exposed in the use class 4 and 5" as part of the project "Investigations concerning the influence of test parameters on the release of biocidal actives from treated timber in leaching tests". Pine sapwood specimens (50x10x150) were pressure impregnated with CCB according to European Use Class 4. Before leaching all samples were stores 4 weeks for fixation. In addition leaching tests were performed according to the European Standard EN 84 by means of EN 113 blocks. Parallel investigations were carried out between two laboratories to assess the repeatability and comparability of the methods. The results of chemical analysis of leachates taken at different time intervals show that similar depletion rates were determined for copper and boron independent on the leaching protocol used. However, the loss of copper as well as chromium in short term dipping experiments was often lower than the detection limit. Furthermore it can be stated that the difference between parallels was higher for the results which were obtained for the OECD guideline that EN 84. A comparison of both laboratory results indicate that a quite good repeatability is given in case of the CCB treated material.
E Melcher, R-D Peek, U Schoknecht, R Wegner


Resistance of the wood of Eucalyptus saligna and Paulownia tomentosa against some wood rotting fungi
1997 - IRG/WP 97-10238
Paulownia tomentosa and Eucalyptus saligna are not autochthonous species in Slovenia and we determined the resistance of their wood against our most common wood rotting fungi. The resistance against Coniophora puteana, Gloeophyllum trabeum and Trametes versicolor was determined according to EN 113 and compared to the resistance of beech (Fagus sylvatica) wood. It was stated, that both paulownia and eucalypt wood samples are much more resistant than beech wood. Especially paulownia wood was outstanding by its natural resistance against tested basidiomycetes.
F Pohleven, M Petric


Determination of the preventive efficacy against wood destroying basidiomycetes fungi, EN V 839 - CEN/TC 38 WG 9
1993 - IRG/WP 93-20015
The WG 9 of CEN TC/38 has presented to EC a mycological test to assess efficacy of preservatives applied by surface process. This method is now an experimental standard (EN V 839) which has to be approved by the different european delegations. The following paper is not the standard as it has been proposed but is a presentation of the principle of the method. The experimental standard specifies a laboratory method of test which gives a basis of the assessment of the preventive action of a wood preservative when applied as a surface treatment against Basidiomycetes fungi. This method is applicable to formulations of preservatives in a ready to use form (organic formulations, organic water-dispersible formulations, water-soluble materials). Series of susceptible wood species specimens are treated on longitudinal faces whith the preservative in test using brushing as surface procedure. Test specimens are then exposed by an intermediate mesh to feeder blocks infestedby pure culture of Basidiomycetes fungi in sterile conditions and penetration of fungi is assessed on cross section sawn in the samples at the end of the test.
D Dirol


Tebuconazole, a new wood-preserving fungicide
1990 - IRG/WP 3634
TEBUCONAZOLE, an anti-fungal triazole compound, has been tested to assess the effectivness as wood preserving fungicide. Tests were made with the active ingredient and also in formulations against basidiomycetes, blue-staining fungi and mould. Results of the DESOWAG laboratories and also from official institutes will be presented. In addition to this there were made different toxicological and ecotoxicological trials according to OECD and EPA guidelines
B Wüstenhöfer, H-W Wegen, W Metzner


CEN Draft Standard (38 N 460F): Méthode d'essai pour determiner l'efficacité d'un produit de préservation du bois en milieu marin
1986 - IRG/WP 4132 F
G Castan


Rapport sur l'activité du Comité CEN/TC 38 "Méthodes d'essais des produits de préservation des bois" du Comité Européen de Normalisation (CEN)
1986 - IRG/WP 2266
G Castan


Proposals for collaborative work on laboratory soft rot testing
1986 - IRG/WP 2265
Proposals for collaborative experiments based on soil burial are presented. It is intended to study the use of defined horticultural loams with a view to obtaining more reproducability in laboratory soft rot tests.
D J Dickinson, S M Gray


A comparison of the effectiveness of a vacuum oven and a wind tunnel in the accelerated ageing of treated wood by evaporation
1989 - IRG/WP 2334
R J Orsler, G E Holland


Bibliographie sur les produits organiques en solvant pour la préservation du bois
1971 - IRG/WP 38
H Alliot


Report of field test results for dichloro-n-octyl-isothiazolone: A potential new wood preservative
1988 - IRG/WP 3495
In a previous report (IRG/WP/3306) we presented preliminary laboratory test results on 4,5-dichloro-2-n-octyl-4-isothiazolone (RH 287). Laboratory data indicated toxic threshold values for RH 287 ranging from 0.37 to 0.50 kg/m³. In this report we present field test results on an IRG L-joint test and an in-ground stake test for RH 287, pentachlorophenol and biocide free test units. (a) L-joint test: After 39 months exposure (Starkville MS.) units pressure treated with 0.05 kg/m³ RH 287 rated 9.7 out of 10. Units dip treated in a 0.5% ai solution of RH 287 rated 10 out of 10. Biocide free controls exposed in the same series rated 5.3 out of 10 after 39 months (b) Stake test: After 48 months exposure in two southern US test plots stakes treated with neat RH 287 in toluene at 4.6 kg/m³ rated between 8.6 to 8.8 out of 10 for decay and 9.1 to 9.8 out of 10 for termite attack. Biocide free control stakes rated O out of 10 for decay and 1.1 to 4.8 out of 10 for termite attack after 48 months. RH 287 continues to show promise as a potential new wood preservative. Results to date were obtained in samples treated with neat RH 287, Formulation of RH 287 into treatment systems specifically designed for above ground or ground contact applications should only improve the already excellent activity seen with RH 287.
D E Greenley, B M Hegarty


A natural exposure weathering test for the evaluation of preservative performance
1992 - IRG/WP 92-2400
Natural exposure weathering tests were carried out by externally exposing treated wood samples for varying periodes of time up to 36 months. In the laboratory these samples were assayed for residual preservative effeciveness using Coniophora puteana FPRL 11E. The results indicated a loss in efficacy over and above that determined using artificial ageing procedures such as EN73 (evaporative ageing) and EN84 (water leaching). Results for two TBT based preservatives indicated a gradual loss in efficacy. Results for the organic biocide 2-thiocyanomethyl-thio benzothiazole (TCMTB) gave a more rapid loss in effeciveness indicative of the high levels of microbial actifity present in the samples. This test provides an intermediate evaluation of preservative performance and permanence between artificial laboratory ageing procedures and the necessary field evaluation using an L-joint type test.
J Brown, G R Williams


Checking of sodium pentachlorophenate fixation in wood
1990 - IRG/WP 3620
In order to estimate the volatilization of sodium pentachlorophenate from treated wood, wood samples treated with pentachlorophenate were analysed after various durations of an EN 73 weathering The results giving no clear evidence of volatilization, treated wood samples were put in a test chamber with precise climatic conditions, the air used in the experiment being analysed. The pentachlorophenate content in air was quantified: 1.8 µg/m³
M Lamour, H Sageot


Final proposals for collaborative work on laboratory soft rot testing
1987 - IRG/WP 2292
In this paper proposals are made to scope, timbers, preservatives, leaching, drying, soil type, moisture content, soil burial (blocks and stakes), incubation and dry weight determination and the expression of results.
D J Dickinson, S M Gray


Virulence tests with fungal strains used in EN 113 CEN ring test. Results with Coniophora puteana (Schum.ex Fr.) Karst
1986 - IRG/WP 2249
D Dirol


Quelques observations biologiques sur la conduite des essais de protection des bois immerges en milieu marin
1976 - IRG/WP 421
P Deschamps


Next Page