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The susceptibility of hardwood plywood to white rot
2008 - IRG/WP 08-40397
The subject of the tests was resistance of veneer hardwood plywood to activity of pure culture of white rot fungus Trametes versicolor. The tested plywood was made with the use of the following glues: urea-formaldehyde (UF), melamine-urea-formaldehyde (MUF) or phenol-formaldehyde (FF). 4, 12 and 15 mm thick plywood was tested. External veneer of the plywood was mostly alder and the inner veneer (core layers) birch and alder. The external and inner veneer of 12 mm thick plywood was exclusively meranti. The test included determination of mass loss caused by the fungus and bonding quality determination by shearing test before and after the fungus growth. Almost none of all tested plywood was resistant to decay caused by the fungus according to test based on EN 113. The results of fungi growth were mass losses of about 14 to 38% and very high reduction of bonding quality. According to EN 314-1 standard the bonding strength of plywood exposed to Trametes versicolor was only 19% to 46% of that of control plywood. Only 15mm thick FF plywood proved to be more resistant to fungal attack. During plywood testing no clear effect of increasing plywood humidity resulting from keeping the samples in uninoculated culture vessels on the strength reduction was observed, however some symptoms of reduction were noted.
A Fojutowski, A Kropacz


Influence addition of boron compounds to adhesives on the bonding quality and fungicidal properties of glued wood
2010 - IRG/WP 10-40497
Wood is one of the most important construction materials. However, users of wood face two issues: limited dimensions and insufficient durability. These issues have been overcome with the development of bonding and wood preservation. The preservation of glued wood is elucidated in this paper. Through the addition of boric acid to adhesives, we tried to improve the fungicidal properties of glued wood. The results of mechanical testing (shear strength and delamination) showed that the addition of boric acid to glue did not have a negative impact on the performance of the glued wood. On the contrary, some properties were even improved. Unfortunately, the addition of boric acid to impregnated wood does not improve the resistance of the glued wood to brown rot fungi.
M Humar, B Lesar, A Ugovsek, M Kariz, P Kralj, M Šernek


Markers of quality in self-bonded beech boards
2017 - IRG/WP 17-40820
A self-bonding phenomenon takes place when five layers of beech (Fagus Sylvatica L.) veneers are pressed at temperatures higher than 200ºC. If the pressing temperature between veneer surfaces reaches at least 225ºC during pressing and if the pressure applied is optimal, water-resistant bonds are formed between veneers. This study investigates the relation of thickness reduction (marker of compression) and mass loss (marker of heat treatment intensity) to boards quality. The effect of water and water vapour on the bondings between veneer in boards pressed at 200, 225 and 250ºC is studied. The conclusion is that pressing 5 layers of 2 mm rotary-cut beech veneer parallel-fibered at 225ºC, 5 MPa and 300 s leads to a thickness reduction of 33.4 % and mass loss of 1.23 %; in such boards bondings are not resistant to liquid water but are resistant to vapour after one adsorption-desorption cycle. When pressing at 250ºC, 5 MPa and 300 seconds, the thickness reduction is 50% and the mass loss 4%; in such boards no delamination was observed when soaked in water. Boards pressed at higher temperature show lower hygroscopicity. Their equilibrium moisture content (EMC) ranged between 3.6 and 7%. Based on the results of this study it is hypothesised that the decay resistance of self-bonded boards will increase when increasing the severity of the hot-pressing.
C Cristescu, D Sandberg, O Karlsson


Effect of acetylation on decay resistance of wood against brown-rot, white-rot and soft-rot fungi
1989 - IRG/WP 3540
Effect of acetylation on decay resistance of wood was investigated using wood blocks of Cryptomeria japonica, Pinus densiflora, Albizia falcata and Fagus crenata. Blocks were treated with uncatalyzed acetic anhydride for different lengths of time and exposed to Tyromyces palustris, Serpula lacrymans, Coriolus versicolor and unsterilized soil. The action of OH-radical on acetylated wood was also examined using Fenton's reagent. The enhancement of decay resistance by acetylation was revealed clearly for all cases of exposures but varying with fungal and wood species used. For a brown-rot fungus Tyromyces palustris, the weight loss reached almost nil in all woods at 20 WPG (weight percent gain) of acetylation, after the striking decrease from 10 to 15 WPG. For a white-rot fungus Coriolus versicolor, it was counted until 12-15 WPG in the perishable hardwoods used, but not in a softwood Cryptomeria japonica, even at 6 WPG. In cases of another brown-rotter Serpula lacrymans and soil burial, effect of acetylation was intermediate between Tyromyces palustris and Coriolus versicolor. Anti-degradation mechanism by acetylation was discussed, from these weight loss - weight gain relationships, and the IR-and 13C-NMR spectral analyses of fungus-exposed wood.
M Takahashi, Y Imamura, M Tanahashi


A case study on quality control on telephone poles as a cost saving tool in Tanzania
1987 - IRG/WP 3418
A sample of 28 CCA treated Eucalyptus poles from a lot of 2,000 poles awaiting delivery to the field, was studied to reveal the quality of treatment. Results showed a product of very poor quality. Average figures for penetration and retention were 8.4 mm and 2.2 kg/m³; these results are 66% and 91% below the required standards, respectively. Consequences of such results are estimated to amount to losses of billion of shillings.
K K Murira


Wood preservation in France. "Bois plus" chain of quality. Description of the scheme early 1989
1989 - IRG/WP 3519
1989 - description of the French "CTB-BOIS PLUS" homologation scheme...
G Ozanne


Treatment of dried sawn spruce and redwood building timbers with water-borne preservatives under a scheme for the quality control of the preservation and preserved wood in the Netherlands
1978 - IRG/WP 3123
Treatment of dried sawn spruce and redwood Building Timbers with water-borne preservatives under a scheme for the quality control of the preservation and preserved wood in the Netherlands. The aim of this article is to give the reader a modest description of the evaluation of fundamental research in wood preservation into a practical application.
H F M Nijman, N Burgers


Wood Preservation in France. A statement of quality control early 1986
1986 - IRG/WP 3389
A statement of quality control in France early 1986 - Summary of new - Standards criteria for preservatives and treated wood - Aptitude of treated wood for use per class of biological hazard
M Romeis, G Ozanne


A simple leaching procedure for in-plant monitoring of CCA fixation
1993 - IRG/WP 93-30023
A simple leaching test is described to quantitatively estimate the extent of fixation of chromated copper arsenate (CCA) preservative treated wood products. It is based on the reaction between diphenylcarbazide and unreacted hexavalent chromium leached from borings taken from treated wood during the fixation process. The test requires about 20 minutes to complete and can be set up in a treating plant quality control laboratory for less than US $1000.00.
P A Cooper, Y T Ung


The role of third party independent inspection agency for wood preservation industry in China
2009 - IRG/WP 09-20425
This presentation attempts to provide a brief historical background and a current status report on the wood preservation industry in China. In addition, it will briefly introduce the need for building the quality control procedures and China wood protection Quality Supervision and Testing Center, a third-party inspection agency. Besides, some suggestions of this industry are proposed for its further development.
Zhenzhong Tang, Changsheng Shen, Yujie Han, Changming Song


Quality assurance approach of the German TMT manufacturers
2010 - IRG/WP 10-40513
Due to an increasing number of TMT manufacturers in central Europe, an organisation of TMT manufacturers was founded in Germany in the beginning of 2010. Since the current level of product testing and property declaration is not satisfying, one of the first activities is the establishment of a quality assurance system. In this paper a concept for quality assurance (QA) will be outlined.
W Scheiding, C R Welzbacher, A O Rapp


Measurement of VOC emissions from curative treated wood: A new emission test chamber
2001 - IRG/WP 01-50166-13
A poor indoor air quality (IAQ) is now recognized as a potential factor affecting occupants health. There are three basic strategies to improve IAQ: source control, improvement of the ventilation and use of air cleaners. Usually, the most efficient way to improve IAQ is to eliminate the different pollutant sources or to reduce their emissions. In order to precisely measure emissions from building products and estimate the potential heath impact of emitted pollutants, standardised analytical methods are needed. The aim of this paper is to present the new standards prepared by the European Committee for Standardization (CEN) and the International Organization for Standardization (ISO) for the measurement of indoor air pollutants and their application to the characterization of emissions from wood products. The prestandard ENV 13419, subdivided in three parts, has been prepared by the CEN technical committee 264 : ??ENV 13419-1 : Building products - Determination of the emission of volatile organic compounds - Part 1 : Emission test chamber method, ??ENV 13419-2 : Building products - Determination of the emission of volatile organic compounds - Part 2 : Emission test cell method, ??ENV 13419-3 : Building products - Determination of the emission of volatile organic compounds - Part 3 : Procedure for sampling, storage of samples and preparation of test specimens. The two first parts of the prestandard ENV 13419 specify a general laboratory test method for the determination of the area specific emission rate of volatile organic compounds (VOCs) from newly produced building products under defined climate conditions in a test chamber (Part 1) or cell (Part 2). The third part specifies for solid, liquid or combined products, the sampling procedure, transport and storage conditions and preparation of test specimens. In France, those European prestandards have been translated by the French Normalisation Association (AFNOR) in three experimental standards : XP ENV 13419-1, XP ENV 13419-2 and XP ENV 13419-3 [1-3]. In parallel to the ongoing work at CEN, the technical committee 146 of International Organization for Standardization (ISO) has prepared the draft international standard ISO/DIS 16000 related to indoor air. Part 6 of this standard specifies a method for the determination of the emission of single volatile organic compounds (VOCs) and total volatile organic compounds (TVOC) from building materials using test chambers and cells [4]: ??ISO/DIS 16000-6 : Indoor air - Part 6 : Determination of volatile organic compounds in indoor and chamber air by active sampling on TENAX TA sorbent, thermal desorption and gas chromatography using MS/FID. It is intended that, after the final voting stage, the CEN prestandards (Parts 1-3) will be taken over by ISO and that Part 6 of the ISO standard will be taken over by CEN as the fourth part of the ENV 13419 prestandard. As an example, the volatile organic compounds emissions from preservative treated wood samples were characterised according to the CEN ENV 13419-1 prestandard describing the emission test chamber method and to the ISO/DIS 16000-6 prestandard for the analytical method. Two representative wood preservatives (hydrodispersable and petroleum solvent formulation) were tested for this purpose. The VOCs concentrations in the test chamber were monitored during 6 days following a simulated curative wood treatment.
F Maupetit, O Ramalho, C Yrieix


Quality control of microwave treatment of timber after dry rot attack
2001 - IRG/WP 01-40205
In Denmark microwave treatment of timber has been used during the last 15 years for eradication of dry rot (Serpula lacrymans). About 1500 microwave treatments have been employed in coorporation with Hussvamp Laboratoriet. Previously all the infected timber was removed plus an extra metre as a safety zone. This meant that all casting boards and plaster had to be removed as well and joists replaced. The cost of such a replacement would often amount to several thousand Danish kroner (100 Dkr . 14 Euro). In cases with sufficient residual strenght of infected timber the cost can be reduced by 40-50% with microwave treatment. Very often it is necessary to support the construction with a fishplate of pressure impregnated wood. Theoretically the lethal temperature for mycelia of Serpula lacrymans is 37°C during 10 minutes, but to ensure that also resting mycelia are killed a temperature of 75°C is used. In order to ensure a sufficient quality of the treatment a thermo controll method has been developed by Hussvamp Laboratoriet whereby the temperature reached inside the wood is registred. In a joist a hole with a diameter of 13 mm is drilled from the side to the centre. A TERMAX or RS 285-936 irreversible temperature sensitive label is placed inside a piece of plastic tube, 6 cm long and 12 mm across, which is inserted into the hole. This is then closed with a corkplug with a diameter of 14 mm and 22 mm long. Afterwards the plug is sealed with a label carrying the logo of Hussvamp Laboratoriet and the text 'Hussvamp Laboratoriets Termokontrol'. The thermo control can be employed at the same time as the attack is delimited or at the start of repair work. After the microwave treatment the seal is removed and the corkplug is pulled out with a corkscrew. The tube with the temperature label is pulled out with a pair of tweezers. On the label the white markings turn black when the indicated temperature is reached. The markings for 65°C, 71°C and 77°C should be black in order to approve the microwave treatment. The method can also be used for other kinds of heat treatment of timber.
J Bech-Andersen, J Andreasson, S A Elborne


A study of wood quality of Juglans nigra and hybrid walnut (MJ 209xRA) : durability against Coriolus versicolor, density and MOR
2004 - IRG/WP 04-10522
The study investigated possible effects of harvesting season on some wood properties of Juglan nigra (JN) and a hybrid walnut (MJ209xRA). The samples were taken from trees which were harvested in June July, August, November of the same year, and March in the year after to determine whether there were any significant differences in wood properties as regards the harvesting seasons. In order to test the durability of the 648 wood samples white rot fungus Coriolus versicolor challenge test (EN113 (AFNOR 1994) was applied by using agar culture medium. The bending strength was also determined after a sixteen-week exposure to the above mentioned fungus. The data obtained clearly indicated that the heartwood of JN was more durable than its sapwood. JN sapwood was more durable than MJ209xRA sapwood. The same trend was observed with the Modulus of rupture (MOR : EN 310): the heartwood displayed higher MOR value than the sapwood. Wood density measurements also demonstrated that the wood density values of the sample heartwoods were much higher than those of the sapwoods. Results also illustrated that, from the wood durability point of view, March is the least interesting period for harvesting. June and November, on the other hand, proved to be more favourable periods as regards harvesting. This study clearly indicates that the durability and the strength of the hybrid walnut (MJ209xRA) are lower than those of the walnut (Juglans nigra), and this fact should be considered in the exploitation of hybrid wood.
B Charrier, F Charrier, D P Kamdem, J B Aurel, G Janin


The effect of felling time of year on CCA fixation rate and quality of selected hardwoods
1998 - IRG/WP 98-40116
White birch (Betula papyrifera), poplar (Populus sp.) and red maple (Acer rubrum) trees were harvested in winter, in spring, before the leaves flushed, after leaf flush and later in the summer. Sapwood discs were cut from the freshly felled trees, dried and cut into 25 mm and 19 mm cubes. The cubes were pressure impregnated with CCA-C and fixed under high relative humidity and at 50°C or at room temperature (21°C) conditions. Fixation rate was measured by expressing cubes periodically and analysing the expressate for CrVI content using a diphenyl carbazide indicator. The expressate was also examined for chromium, copper and arsenic using ASOMA X-ray fluorescence spectroscopy. Red maple wood harvested in spring fixed more slowly than wood cut in either the winter or the summer. This is thought to be related to the sugar, starch and other nutrient content of the wood at different times of the year. The time of year of felling had no consistent effect on the speed of fixation in white birch and poplar sapwood. Fixation quality was evaluated by leaching studies on 19 mm cubes using AWPA standard E 11-87. As has been observed elsewhere with red maple and other species, rapid fixation rate is accompanied by poor quality of fixation of CCA components, and especially of arsenic. We conclude that the season during which red maple is harvested can have a great effect of CCA performance in this species, which helps explain variable fixation rates and quality of fixation observed previously with this species.
Y T Ung, A Taylor, P A Cooper, D P Kamdem


Work programme of CEN/TC 38 (April 1999) and European publications
1999 - IRG/WP 99-20165
Scope of the CEN/TC38: Standardization of the characteristics of natural or conferred durability of wood and its derived materials against biological agents, including the characteristics of protection products and associated processes to obtain this durability. This applies in particular to: - the identification of hazard classes-, - the test methods (wood preservatives and treated wood and wood based materials) and interpretation of the results; - the specification of wood preservatives and treated wood by classes of hazard including processes-, - quality control methods-, -terminology.
R Hüe


Mechanical resistance of Pinus radiata CCA treated and face jointed with PVA adhesive
1999 - IRG/WP 99-40140
Due to the increased use of Pinus radiata timber composites (laminated structural members, panels, etc), its low natural durability and the toxicity of phenol-formaldehyde type adhesives, a PVA (polyvinyl acetate) adhesive was evaluated in machined and rough CCA treated and untreated face joint samples under DIN 68602 (EN 204-205) standard for groups of requirement 3 and 4. The results showed that the adhesive resisted the face joint in machined samples without CCA treatment. Rough wood samples did not meet the standard. The effect of the CCA treatment up to 4 kg oxide/m3 prior to the bonding produced a decrease in the mechanical strength of the joint in both types of roughness. Treated and machined samples had similar behaviour as rough untreated samples. The selected adhesive is not good in applications on weather exposed service of composites, since in group 3 requirement all samples failed the bending test at the adhesive joint and not at the clean wood portion.
M C Rose, L Reyes, P León


The dip diffusion treatment of tropical building timbers in Papua New Guinea
1972 - IRG/WP 310
In Papua New Guinea a dip diffusion process using a multi salt preservative developed by C.S.I.R.0. has been in commercial use for 8 years. Over 200 million super feet (236,000 m³ ) of timber has been treated during this period and current rate of treatment is 34 million super feet (80,400 m³ ) of timber per year in 70 licenced treatment plants. The process has been found to be simple to apply, convenient to control and has proved very successful in the protection of timber used out of ground contact and protected from the rain. No serious health hazards to process operators or product users have come to light. In common with other countries in the wet tropics P.N.G. is faced with very serious biological deterioration hazards to timber in houses but dip diffusion has overcome the major problems. During the 16 years in which dip diffused timber has been in service in P.N.G. there have been no notable falldowns, the only falldowns reported being in mouldings in which heavy dressing has removed the preservative envelope, but this is a very rare occurrence and cannot be considered of economic importance.
C R Levy, S J Colwell, K A Garbutt


Decay Resistance and Bonding Properties of Structural Flakeboard
2002 - IRG/WP 02-40233
Experimental structural flakeboard panels consisting of differing furnishes and resins were produced and tested for internal bond, linear expansion, thickness swell, and decay resistance. One group of panels was produced with recycled CCA-treated wood as the furnish and commercial phenol formaldehyde (PF) resin as the binder. Other groups of panels were produced with either mixed hardwoods or southern pine as the furnish and then sprayed with a co-reacted soy-flour PF resin or a commercial face or core resin. The recycled CCA-treated panels contained 5 different furnish ratios (0:100, 25:75, 50:50, 75:25, and 100:0) of recycled CCA-treated southern pine and virgin, untreated southern pine. Tests on the panels bonded with co-reacted soy flour PF indicated that 30% substitution of phenol with soy flour in the resin system did not appreciably promote decay or reduce IB strength. As expected, panels produced with a higher ratio of recycled CCA-treated wood furnish, were generally subject to less weight loss during decay tests for brown rot (Gloeophyllum trabeum, ATCC 11539) and white rot (Trametes versicolor, ATCC 42462) but yielded lower IB values. Research in currently in progress to assess the resistance of all the aforementioned panel types to the Formosan subterranean termite (Coptotermes formosanus Shiraki).
T F Shupe, Chung-Yun Hse


The effect of mortality diseases on wood quality of sissoo (Dalbergia sissoo Roxb)
2006 - IRG/WP 06-10569
Sissoo (Dalbergia sissoo Roxb.) is a lagre deciduos, fast growing, strong light demanding and leguminous tree specie. It is an important multipurpose specie widely being planted in the agro forestry and and social forestry pratices in Bangladesh, particularly in the north and south-western parts of the country. On account of its better quality, sissoo is valued as good as construction and utility timber in Bangladesh. It is used as high value timber, wood fuel, nitrogen fixing and fodder trees. For about a decade, sissoo plantings of varying ages have been found dying due to an unknown cause. By 1996 the mortality was wide spread especially in the western part of the country, and it affects the wood properties of sissoo. The wood properties are very important in selecting wood for numerous uses. So, a comparative study of various physical properties of wood among sound, moderately affected and severally affected sissoo trees was conducted. Sound, moderately affected and severally affected sissoo trees showed significant differences in respect of tangential, radial, longitudinal and volumentric shrinkage respectively. Radial shrinkage didn’t differ significantly among top, middle and bottom sections of a particular condition of wood and the same result was of tangential, longitudinal and volumetric shrinkage. The same trees also showed a significant difference in density, but the density didn’t differ significantly among the top, middle or bottom sections of a particular condition of wood. Besides these, the presence of decay, stain, tunnel and discolouration were observed which also determine the wood quality. In sound, sissoo wood these are absent, but in disease affected sisso wood decay, stain, tunnel and discolouration are present which deteriorate the wood quality. It is observed that the wood quality of sound sissoo trees have been found superior to that of moderately affected and severally affected wood.
M M Islam, M O Hannan, G N M Ilias


Sampling rates and the probability of detecting defective treatment in the sampling of preservative treated timber
1987 - IRG/WP 2277
When attempting to enforce standards of penetration and retention set for treated timber, the regulating authority must establish a sampling or inspection scheme which will prevent large quantities of substandard product entering the market. On the other hand, the scheme should not penalise treaters for the small quantities of such material which are inevitably produced by any industrial process. Thirteen alternative sampling schemes which could be used to periodically sample individual treatment plant production are compared. The risk of allowing continued production of excessive unacceptable material is compared with the risk of unfairly penalising the treater for producing only small amounts. Schemes are evaluated in terms of the effect of sample size, number of permissible failures at each sampling, and number of warnings issued before taking action. Schemes which present the best balance between opposing risks are identified.
M J Kennedy, L E Leightley


Relationship between bond strength and surface characteristics of CCA-treated Douglas-fir
1993 - IRG/WP 93-30008
Chromated-copper-arsenate (CCA) treated Douglas-fir was laminated using a commercial phenol-resorcinol resin. CCA treatment enhanced the water repelleney of wood espeeially in the presence of extractives. However, the shear strength of CCA treated wood was 12% lower in dry condition and 38% lower in wet condition after six cycles of vacuum-pressure test than that of untreated wood. Slight removal of treated wood surface by planer or sander contributed for better adhesion, although it was not enough. The characteristics of treated wood surface was analyzed by X-ray photoelectron spectroscopy (XPS). CCA treatment increased C1 (C-H) and decreased C2 (C-OH), indicating migrated exctractives have enhanced the water repelleney of treated surface. The removal of hydrophobic surface of CCA-treated wood decreased C1 component of C1s spectra on the new surface.
K Yamamoto, J N R Ruddick


Experiences with penetration of copper-based wood preservatives
2001 - IRG/WP 01-20233
In the Nordic countries there is a long tradition of result type based specifications for preservative-treated wood. A common Nordic standard for treated pine (Pinus sylvestris) wood was published in 1976. After a revision in 1989 this standard, then named INSTA 140, defined four classes of treated wood: M, A, AB and B. Treaters producing according to this standard had to be affiliated to a quality control and certification scheme. When the European standards EN 351 and EN 599 were to be implemented, the Nordic Wood Preservation Council issued a Nordic application document where the traditional wood preservation classes were defined in terms of EN 351 and EN 599. The present paper describes briefly how the European standards have been implemented in the Nordic countries. During the last years the use of CCA-preservatives has been restricted in the Nordic countries. New copper-based, chromium and arsenic free preservatives have been introduced for commodities above ground. This has by no means been without complications. The treaters have had severe problems to comply with the treatment requirements. Pilot plant treatment trials confirm that the penetrating properties of the chromium/arsenic free preservatives differ substantially from CCA. Experience from the Nordic quality control and certification scheme shows that it is often difficult to judge the penetration of the chromium and arsenic free preservatives. Different copper reagents give different results. A comparative test showed that ammoniumhydroxide and rubeanic acid as reagent for copper was the most sensitive to copper and performed better than other reagents tested.
J Jermer, F G Evans, I Johansson


Natural Durability of Tropical Species – Variations and Prospects
2005 - IRG/WP 05-10568
The tropical timber resources of the world play an unequivocal role in economic development of both the tropical timber producing and importing regions. This paper describes natural durability as an important and preferred wood quality of tropical species of the world with emphasis on Malaysian hardwoods, the link between various aspects of tropical hardwood durability, hardwood utilization and biological hazards of different regions of the world, the resource evolution in the utilization of tropical hardwoods including the introduction of plantation-grown durable species and increased use of wood composites, a summary of research on the major cause of variations in natural durability of tropical hardwoods focusing on heartwood extractive bioefficacy, their microdistribution in relation to natural durability, and heartwood extractives as future sources of novel organic wood protecting chemicals. Recent advances in genetic manipulation of disease resistance in certain tree species makes it theoretically possible to genetically produce naturally durable tropical species with their accompanying inherent anti-microbial substances, which if/when realized, would provide significant opportunities to produce transgenic naturally durable species befitting a natural wood protection concept.
A H H Wong, Yoon Soo Kim, A P Singh, Wang Choon Ling


Rapid analysis - chances and limitations
1999 - IRG/WP 99-50130
The reuse of wood out of service in the particle board industry demands a proper handling and separation of assortments with differing content and nature of preservative. A pre-selection based on visual and olfactorial characteristics can be carried out for certain assortments like sleepers, poles, etc. Problems arise from diffuse and less intensive treated wood which is regularly dip-treated or brushed and which may have been leached out by rain since demolition. On the other hand, due to possibte leaching processes, previously untreated wood can be contaminated during storage, thus resulting in a low and ineffective content of preservative, but in a higher concentration than the limit values will allow. Thus, analysis of wood out of service before reuse is recommended. Due to the high throughput during processing, there is no time for classical laboratory analysis. For this reason, the objective of a joint project financed by the German Federal Environmental Foundation (DBU) was to investigate various techniques for rapid analysis and to develop a successful approach to be used in practice. An overview of the state of developments and the possibilities for the rapid analysis of wood waste were presented at IRG 29 (IRG/WP/98-50104). Now, the joint research project reaches its end showing the possibilities and limitations of rapid analysis. In conclusion, the techniques showed their ability for the detection of a broad range of organic and inorganic wood preservatives in a range representing the spectrum from natural content up to impregnation by pressure treatment. The prerequisite is a homogenous sample due to the extreme inhomogeneous distribution of wood preservatives in wood after service. Thus, rapid laboratory analysis can be executed but a routines analysis of solid wood out of service in the entrance control seams not to be applicable.
A Peylo, R-D Peek


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