Your search resulted in 316 documents. Displaying 25 entries per page.
Research on the effects of wood preservatives on the physical and mechanical properties of Iranian beech (Fagus orientalis Lipsky)
1985 - IRG/WP 3351
This research work was conducted with the aim of using preservatives such as Basilit and Wolman Salts with Iranian beech and to study any physical and mechanical changes these might have on the beech species of Iran. Samples were divided into three groups; one group were used as untreated controls, the second group was treated with Basilit and the third group was treated with Wolmanit. Results obt...
P Niloufari
The Biocidal Products Directive ( 98/8/EC ) - its consequences for the wood preservation industry
2001 - IRG/WP 01-50166-04
1. The Current Position
This European Union Directive is one of the most technically complex pieces of legislation that has been developed by the European Commission (EC). Although the Directive was to have been implemented in the legislation of individual Member States of the EU by May 2000 progress has been slow. A number of Member States have yet to declare the Competent Authority who will handle their legislation. The body text of the Directive cannot stand-alone and is dependent on ancillary regulations and the development of technical guidance for both the Competent Authorities in the Member States and also industry to understand their roles in the whole process for the regulation of biocides and the biocidal products containing them. The process is far from complete in terms of a piece of workable legislation and this leaves not only industry but also the Competent Authorities with significant areas of uncertainty. This is potentially economically and socially damaging to the marketing and use of biocides and biocidal products. Because of this evolutionary process this paper can only be written in general terms as by the time the symposium takes place some significant changes to the position at the time of writing may have occurred.
2. Background
The Biocidal Products Directive (98/8/EC), (BPD), is a directive which requires that biocides ( as active substances) are approved for use within the EU and the individual biocidal products containing these active substances are approved for use by the Competent Authority(s) of the Member State(s) in which it is intended to market the product. The product authorisation obtained in the first Member State should be mutually recognised by the other Member States in which application for authorisation to place the product on the market is sought. The Directive has to be seen in the context various other Directives, notably the Plant Protection Directive 91/414/EC). Biocidal products are grouped in the directive into twenty three "product types" and wood preservatives are Product Type 8. The intention of the directive is to harmonise the requirements for the placing of biocidal products and active ingredients on the market throughout the EU. EU wide use of so-called Common Principles are intended to be used to assess the dossiers in order to achieve a common approach and eliminate the current situation where individual Member States apply their own particular national approaches and criteria in the assessment and regulation of products . Annex IIA of the directive identifies the data requirements for the active substance and Annex II B for the biocidal product. There are additional data requirements identified in Annexes IIIA and IIIB for each product type reflecting potential for exposure to man and the environment.
3. Entry onto Annex I
Any new active substance will require approval before it or any biocidal products including it can be placed on the market. The dossier to be submitted to the EC will have to include additional data and risk assessments for the product types (as defined in the BPD) in which it will be intended to be used. For those active substances that are accepted as being existing substances on the market before May 2000 (say in wood preservatives) these will be ranked and prioritised. This process is being defined in the so-called: Review Regulations.
4. An environmental directive
There is no doubt that this Directive has a high environmental content in terms of the data and the associated risk assessments which are to be prepared. The protocols and the end points for some of these data requirements are still being developed. In general the EC considers that modelling exposure using human and environmental exposure scenarios covering the end use of the product is an acceptable approach . Data are required to enable these scenarios to be modelled and risk assessments made. It is necessary that regulators do not make decisions based on hazard assessment alone in the absence of fully worked out and agreed emission scenarios to define exposure levels which generate a realistic worst case risk assessment. Risk is a function of both hazard and exposure. A lot of work has been done in the development of Technical Notes for Guidance intended to help the regulator and the applicant in the submission and the interpretation of the data. Whilst it may be the case that the human toxicity data requirements still leave questions to be answered it is in the environmental aspects part of the regulatory process where there is still much work to be done. The Directive would seem to rely heavily on the development of Pass / Fail criteria in simulation tests. This is a big subject and of key importance to the risk assessment.
5. Wood preservatives ---- a test case
Wood preservation has achieved a certain reputation. On the one hand it is said that a prime reason for the development of the Biocidal Products Directive arose from European problems in the regulation of the marketing and use of dangerous substances, notably wood preservatives. On the other hand because wood preservatives have been regulated by a number of Member States for many years it is believed they are well understood. The EC and the Member States also wanted to be seen to have achieved early success in the implementation of the Directive therefore the decision was taken to start, following failings with the speed of progress of the Plant Protection Products Directive, with a product type they knew all about i.e. wood preservatives. There is no doubt that there is a much greater understanding on the exposure scenarios, both human and environmental, for wood preservatives than many other product types. However, would it not have been better to have tackled some of the other product types where such an understanding is much less well developed? It is regrettable that the EC and Member States did not feel able to accept the results of an EC sponsored study (Haskoning report) on the assessment of risks for all the product types covered under the BPD. The results of this study clearly showed that wood preservatives did not constitute the most significant risk to man or the environment and in fact the risk was significantly greater for other product types.
6. Wood preservatives and the OECD Biocides Programme
Another speaker will be covering this subject in more detail. Suffice it to say that because of the perception there was good knowledge about wood preservatives again they were selected as the pilot for an OECD project looking at environmental and human exposure assessment under the OECD Biocides Programme. The findings from two OECD Workshops actually demonstrated there was still much to be learnt about wood preservatives in order to refine the risk assessments to a state where they would be sufficient for the requirements of the BPD. This work is ongoing but it clearly demonstrates the problems that both the regulator and industry will have in the preparation and the assessment of the dossiers for both the active substances and the biocidal products. This is especially the case for other biocidal products that have not been subject to the same kind of regulation that wood preservatives have subjected to in the past.
7. Inorganic and organic biocides
With current wood preservation technology there is still a dependence on inorganic chemicals such as copper (in conjunction with other biocides) or with chromium, as well as arsenic and boron for many end use applications. This is very much the case where a long term service life is a key factor in the use of treated wood for that end use. These substances are commodity chemicals and are also covered under the Existing Substances Regulations (EC) 1488/94. There is also work going on revising the Technical Notes for Guidance covering them . This includes a significant addition in the environmental risk assessment area. Efforts are being made to integrate and coordinate the requirements for both the BPD and the Existing Substances Regulations and OSPAR ( OSPAR Convention for the Protection of the Marine Environment of the North-East Atlantic). OSPAR refers to the Oslo Paris Convention. Whilst the BPD seems primarily aimed at the regulation of biocides based on organic chemicals wood preservative products may contain both inorganic and organic components. Indeed there are probably few wood preservative formulations on the market that contain only one active substance. This must have a significant impact on the way the dossiers are prepared for the active substance and the biocidal products and how they are assessed both at the EC and the Member State level.
8. Consequences of the BPD for the wood preservation industry
Whilst this paper addresses the consequences for the wood preservation industry per se, it must not be overlooked that there may be implications for the fabricaÈors of articles made from treated timber. Some current wood preservative formulations may over a period of time be withdrawn from the market because the risks and costs of generating the data and the preparation of the dossier make the product economically unviable. The presence of large working volumes of wood preservative solutions at treatment plants requires realistic withdrawal periods to avoid the unnecessary disposal and associated environmental risk of products that have been used satisfactorily for many years.
9. Availability of active substances
The structure of the industry has changed dramatically in the past few months and there is no doubt that other changes both within and outside the wood preservation industry itself are yet to happen. The original differentiation between formulator of wood preservatives and active substance suppliers to the wood preservation industry has become blurred. Some of the active substances used in wood preservation are used in other either other biocidal product types or in products regulated under another directive, e.g. Plant Protection Products Directive 91/414/EC.
10. Data protection
This continues to be a key issue for industry and some companies may find it strategically or financially necessary not to support an active substance in a particular product type thus leaving that sector without being able to use the active substance. The coming months will start to reveal which active substances are likely to be supported, at least through the notification process. Formulators are therefore in a close dialogue with their suppliers to try to determine their intentions on whether or not they intend to support their active substance. Today's wood preservative formulations are largely multi active substance based. Product costs, efficacy spectra, niche marketing and other considerations have made this process inevitable. New wood preservative formulations take time to research and develop and the continuity of availability of a choice of active substances is of key importance. A lack of adequate return on investment necessary to sustain the development of new products could have a negative impact on innovation and the rate of introduction of new products. It is extremely unlikely that any new active substance will be solely developed for use in wood preservation. This would be an effect contrary to expectations of the EC. The situation with wood preservatives is complicated by the fact that treated wood is a construction product and comes under the scope of the Construction Products Directive (89/106/EEC) (CPD). Products under the scope of the CPD are required to meet certain so-called essential requirements and one of these is durability. Demonstration of compliance involves the extensive suite of CEN wood preservative efficacy tests. Even relatively small changes in formulations may require extensive re-testing under the EN 599 regime in some Member States.
11. Task Forces
Companies are encouraged by the EC to enter into Task Forces in order to reduce the burden of testing on animals and also to reduce the number of dossiers to be reviewed for each active substance. Ideally, and understandably, the EC would like one dossier per active substance. Parts of the wood preservation industry have been co-operating in Task Forces and much practical experience has been gained. Even closer co-operation will be required and this will enable companies to pool experience and expertise and manage their financial exposure to potentially high regulatory costs by sharing them amongst a larger number of parties.
12. Financial aspects
Industry will have to make some best guesses with respect to its investment programmes for supporting its portfolio of products. Formulators and active substance suppliers are likely to group into Task Forces in order to reduce their costs in terms of data generation and the fees likely to be charged at the EU and the Member State level for the assessment of the dossiers. The compilation of the dossiers requires specialist expertise to assist the industrial applicant(s). This is likely to cost in the order of £100,000 per active substance, not including the costs of generating any data. The Rapporteur State's costs for reviewing the dossier is also expected to be of the same order. Clearly these kinds of costs will impact on innovation. An adequate payback must be available to the company to justify this level of investment.
13. Will mutual recognition work?
Member States are required to recognise the authorisation of the biocidal product placed on the market in the first Member State when subsequent applications are made to place the product on the market. This is a fundamental principle of the BPD, although there is concern that Member States continue to have enough flexibility to prevent this happening if there are particular concerns in that Member State. Industry very much hopes this will not be the case and that mutual recognition, a fundamental principle of the BPD, will work in practice.
14. Environmental aspects
Biocidal products such as wood preservatives are generally applied in controlled situations and not over large areas. Consequently any emissions can be considered to be from discreet sources, such as treated timber or potentially from timber treatment plants. This is in contrast to plant protection products and some other biocidal products that are usually dispersed over a relatively large area. Because of this a lot of work is required to be done to re evaluate how the environmental aspects of biocidal products such as wood preservatives can be assessed in an objective manner. The criteria that define an emission and how the PEC (Predicted Environmental Concentration) for each environmental compartment is determined are critical. The wood preservation industry, through the EWPM (European Wood Preservative Manufacturers Group), has been working with institutes and other interested parties in a co-operation known as the EFG (Environment Focus Group) to progress the development of appropriate methodology. Data will be required for both primary and secondary exposure to treated timber. The protocols for this work are yet to be agreed. This work is being further progressed in the OECD together with input from CEN TC 38 WG27. This co-operation between the OECD and CEN is extremely significant in that it is, I believe, the first time such a co-operation has taken place in the development of an OECD Guideline. If one considers all of the end uses where treated timber may be found carrying out a risk assessment with few guidelines on how it should be done is a very uncertain process for both industry and the regulator. Reliance on so-called expert opinion may be inadequate.
15. Comparative assessment (the substitution principle)
This is a process whereby the health safety and environmental properties of acti_u101 ? substances used in the same product type could be compared and those with the most undesirable properties would not be placed on Annex I. Consequently biocidal products containing them would have to be removed from the market. This process is embodied in the BPD but it was initially considered that it would only be applied in the event of problems arising with active substances or products containing them rather than being used as a screening tool early on in the review process for active substances. This area is still an uncertain one with Member States having different interpretations of this principle. It is unfortunate that the wood preservation industry could be used to test out this concept at a European level. The consequences of this principle could be further losses of active substances available to the wood preservative formulators.
16. Substances of concern
The BPD is not only concerned with the active substances that are formulated into the biocidal product but also with so-called "substances of concern". These are defined as any substance, other than the active substance, which has the inherent capacity to cause an adverse effect on humans, animals or the environment and is present or is produced in a biocidal product in sufficient concentration to create such an effect. There are significant implications for the formulator of the biocidal product . The formulator may have to submit an extensive dossier containing toxicological and metabolic as well as ecological data on each of the substances of concern when seeking approval for the biocidal product. There may be classes of compounds that become unavailable to the formulator either because of the risks posed by the co-formulant or because the cost of generating data will be uneconomic.
17. The wood preservation Industry's view on the BPD
Industry has supported the development of the BPD since its conception in 1989. It is still supportive it but believes that the degree of complexity is disproportionate to the level of risk when it comes to wood preservatives. After all wood preservatives have been regulated for a long time and in reality there have been few significant health safety and environmental problems associated with them. Industry believes there is no need to determine an absolute understanding about a biocide and its application but rather there is a need to determine the level of understanding that will enable characterisation so that a risk assessment can be made. The wood preservation industry has sought either directly or through representative bodies a pro-active and collaborative approach with the regulators although at times this appears to have encouraged inappropriate demands. The regulators have invariably responded positively to this however they may not always understand the burden in both time and resource in having made wood preservatives the test case. Industry hopes that its efforts to be pro-active will be recognised and will be dealt with equitably when considered before the other product types defined in the Biocidal Products Directive.
D Aston
Tolylfluanid - fungicide against blue stain in service
1992 - IRG/WP 92-3736
Physical and chemical properties and efficacy of Tolylfluanid are compared with the properties of Dichlofluanid. Whereas the difference in the molecular structure influences the physical properties significantly, the efficacy of both fungicides is comparable. The toxicological and ecotoxicological profile of Tolylfluanid is summarised....
H-U Buschhaus
Determination of physical properties of wood by Novel Guide
2006 - IRG/WP 06-40345
In empirical and theoretical determination of physical properties of wood, a schematic guide has been developed (as a novel guide) for the purpose of bringing facilities to researchers with a processing quantity in terms of data compilation. In this article physical properties of wood have been briefly described in respect to their effect on impregnation process, and technical information has been...
I Usta, M D Hale
Effects of timber surface properties and dipping conditions on uptake of antisapstain actives from two aqueous suspensions, and ultimate effects on efficacy against mould and staining organisms
1995 - IRG/WP 95-30073
Green-off-saw rough sawn Pinus elliottii (slash pine) boards were dipped in aqueous suspensions of two antisapstain formulations, and the resultant surface retentions of active ingredients MTC (methylene bisthiocyanate), CTL (chlorothalonil) or TCMTB (2(thiocyanomethylthio)benzothiazole) were monitored by chemical analysis. Surface retentions increased with suspension concentration and surface rou...
M J Kennedy, T L Woods
Specific gravity and moisture content of particleboards treated with various chemicals
2005 - IRG/WP 05-40310
The aim of the study was to investigated the effects of particleboard treated with various chemical substances on specific gravity and moisture content
The wood raw material used in the experiments were the mixture of coniferous wood [70%, Pinus brutia Ten., Pinus nigra Arn (Lamb.), Cedrus libani Ait.] and black poplar (30%, Populus nigra L.). In this mixture, barks have been accepted up to 5 per...
Ü C Yildiz, A A Var, H Kalaycioglu, S Yildiz
Experimental test site to prevent maritime pine logs from bluestaining: water-spraying and water-immersion methods
2003 - IRG/WP 03-10497
Following a storm which led to windfall wood, a research project was launched to develop preservation methods with a low environmental impact for maritime pine logs. These preservation methods are intended to be suitable for large-scale storage areas of maritime pine. In addition the aim was to maintain wood quality during long term storage. An experimental field test with 1 900 m3 of maritime pin...
I Le Bayon, H Callot, D Reuling, C Brunet, P Castéra
A study on biological properties of small black sawer beetle (Monochamus sotor L.)
1992 - IRG/WP 92-1525
The biological properties of the small black sawer beetle (SBSB), which is mainly destructive insect species for fire-damaged timbers in Da Xing An Ling region in China have been researched. Their main properties are: 1. The SBSB occures one generation one year in this region and their larvae overwinter in xylem. 2. The pupation starts in in late May and peak occures in early June. 3. The emergenc...
Lu Wenda, Shao Jing Wen, Li Jian, Men Fan rong
The Chemical and Biological Properties of Polymeric Betaine
2009 - IRG/WP 09-30512
Didecyl polyoxyethyl ammonium borate (DPAB), also known as Polymeric Betaine, was developed as a co-biocide for chromium-free copper based wood preservatives in Europe in the 1980’s. DPAB as a wood preservative has been reported previously. This paper summarizes the chemical, physical, and biological properties of DPAB. ...
H Härtner, S Schmitt, Futong Cui, H M Barnes
Bending Properties of FRT OSB
2012 - IRG/WP 12-40600
Fire retardant treated (FRT) oriented strandboard (OSB) and plywood of different widths were tested in static bending to determine width effects. Results were consistent with previous width effect studies and showed that increasing specimen width results in a decrease in sample MOR properties among all the sample groups tested in this study. Increasing sample width for OSB samples leads to more ...
J M Hill, H M Barnes, S Q Shi
Use of Transverse Compression Properties as a Measurement of Wood Biodeterioration, Part 1 of 2 - Effect of White-Rot on Yellow-Poplar
2002 - IRG/WP 02-40239
The soil block and agar block test methods are used extensively as a screening process for potential and modified wood preservatives. The extent of decay in standard screening tests, indicative of preservative efficacy, is currently based on mass loss. Mass loss techniques, due to their limit of sensitivity in detecting significant mass loss vis-à-vis decay, require an extended fungus exposure ...
S Janzen, D D Nicholas
Physical and mechanical properties of a suitable constructional timber of Bangladesh
1997 - IRG/WP 97-40102
The study of physical and mechanical properties of lohasirish timber (Derris robusta Roxb.) grown in Bangladesh revealed that the sapwood is whitish to yellowish white, heartwood is dark grey to blackish in colour; the texture is moderately fine, the grain in mostly straight and coarse with whitish rings of parenchyma; shrinkage is moderate; the EMC ranges from 12% to 16%; fuelwood colorific value...
A K Lahiry
Fungicidal properties of boron containing preservative Borosol 9
2004 - IRG/WP 04-30348
The fungicidal properties of new boron containing wood preservative Borosol 9 is described in this paper. These properties were of particular interest as this new boron containing preservative, exhibit very good performance against wood damaging insects. But because the tested boron formulation contain also nitrogen compounds, we wanted to verify if nitrogen as a nutrient could promote...
G Babuder, M Petric, F Cadež, M Humar, F Pohleven
Heat treated timber in Finland
2000 - IRG/WP 00-40158
Heat treatment permanently changes the physical and chemical properties of wood by means of high temperatures (150 - 240°C). Heat treatment darkens the colour of the wood. Heat treatment improves the equilibrium moisture content of the wood and the shrinkage and swelling of the wood is reduced. Very high temperatures improve the resistance to rot and also reduce the susceptibility to fungal decay...
T Syrjänen, E Kangas
Antifungal properties of new quaternary ammonium and imidazolium salts against wood decay, staining and mould fungi
2004 - IRG/WP 04-30347
The biological activity of twenty-four potential wood preservatives – imidazolium and quaternary ammonium salts with a modified anion structure was determined employing screening agar-plate and agar-block methods. Experiments were carried out on Scots pine (Pinus sylvestris L.) wood. The aim of the performed studies was to investigate the effect of structure modification of IC and QAC with organ...
J Zabielska-Matejuk, W Wieczorek
Ancillary properties of vapor boron-treated composites
2001 - IRG/WP 01-40210
This paper discusses the water absorption, thickness swelling, and internal bond strength of North American composites treated using a vapor boron treatment process. For oriented strandboard, high boron loadings led to lower internal bond strength and lower thickness swelling. Water absorption results were variable but no deleterious effect of treatment was noted. For medium density fiberboard, th...
W A Jones, H M Barnes, R J Murphy
Effects of methoprene on Coptotermes formosanus (Isoptera: Rhinotermitidae)
1987 - IRG/WP 1322
Methoprene affected differentiation and survival of Coptotermes formosanus Shiraki in laboratory studies. At 5, 9, 13, and 17 weeks, superfluous intercastes and presoldiers were produced when termites were allowed to feed on concentrations of 1,000 and 2,000 ppm methoprene in wood blocks. Colony numbers were significantly reduced after 13 and 17 weeks of exposure to the insect growth regulator. Te...
S C Jones
Heat treatment of wood strands for OSB production: Effect on the mechanical properties, water absorption and dimensional stability
2002 - IRG/WP 02-40238
The effect of heat treatment on the mechanical and physical properties of commercial OSB strands was evaluated. Heat treatment was applied under inert atmospheric conditions to wood strands. The aim of this study was to examine the heat treatment parameters to achieve significant reduction of thickness swelling (upon exposure to moisture in service) without causing excessive
reductions in stren...
G J Goroyias, M D C Hale
Investigation of some technical properties of heat-treated wood
2003 - IRG/WP 03-40266
The objective of this study was to investigate some technical properties of heat-treated wood.
Wood heat-treated according to a process intended for wood in above-ground end-uses (European hazard class 3) was subject to the following:
· A delamination test according to EN 391 with glulam beams made of heat-treated pine (Pinus sylvestris) and spruce (Picea abies) laminations, assembled with PR...
C Bengtsson, J Jermer, A Clang, B Ek-Olausson
Dimensional stability, biological resistance, and mechanical properties of phenol-resin-treated particleboard
1990 - IRG/WP 3622
Particleboards were treated with a low molecular-weight phenol-formaldehyde (PF) resin and their enhanced properties were evaluated. Besides dipping of particles in aqeous solutions of resin, and spraying of resin solutions before spray of the conventional phenol-formaldehyde resin for adhesive binder, one step treatment by spraying of the mixture of the low molecular-weight resin and the adhesive...
Y Imamura, H Kajita
Vapour boron treatment of wood based panels: Further studies on mechanical properties
1993 - IRG/WP 93-30028
Samples of medium density fibreboard, chipboard and oriented strandboard were treated to two retentions of boric acid by vapour phase methods. The results of short term mechanical tests on this material were discussed by Hashim et al. (1992). The present paper discusses results with long term studies on bending and impact resistance with panel types. Long term tests of impact resistance showed no ...
R Hashim, R J Murphy, D J Dickinson, J Dinwoodie
The use of TCMTB in applications other than sapstain prevention: A review
1990 - IRG/WP 3606
The efficacy of TCMTB against staining fungi and surface moulds has been thoroughly investigated during the last decade. As a result, the chemical is used as an alternative to the chlorinated phenols in various parts of the world for the preservation of freshly sawn timber. Less known are the data obtained against brown rot, white rot and soft rot fungi. The termite repellent and bactericidal prop...
R Van der Eynde
Bifenthrin, a new insecticide for the control of termites and wood-boring insects
1995 - IRG/WP 95-30076
Bifenthrin, a new insecticidal compound Bifenthrin has been extensively tested, to determine its potential use to control termites and other wood destroying insects. Bifenthrin is effective at extreme low rates which can minimize human and environmental exposure to the product. Results of tests carried out by several research institutes and by FMC in different countries will be presented. The phys...
G Rustenburg
Amines – Promising Wood Preservatives
2002 - IRG/WP 02-30287
Environmental concerns require a new approach in the field of wood protection. Band of many traditional wood preservatives has lead to intense researches for new environmental-friendly wood preservatives. Amines seem to be promising substitutes for classical biocides. Fungicidal and leaching resistance as well as some other chemical analysis of beach and Norway spruce samples treated with ethanola...
M Humar, F Pohleven, Š Kesnar, P Kalan
Bending properties of treated western hemlock plywood
1996 - IRG/WP 96-40064
This study investigated the mechanical properties of western hemlock plywood after treatment with waterborne preservatives and redrying. Unlike previously reported results for southern pine plywood, western hemlock plywood was more sensitive to redrying temperature than to preservative treatment. Generally, western hemlock plywood was affected by temperature and other variables. Losses in mechanic...
H M Barnes, A Khouadja, D E Lyon