Your search resulted in 404 documents. Displaying 25 entries per page.
Quantitative assessment of field specimens. A proposal for discussion
1980 - IRG/WP 2143
H Friis-Hansen
The performance of softwood species used as poles in Queensland
1985 - IRG/WP 1253
In Queensland, the conifer Pinus elliottii could provide material suitable for use as poles. Full size pole material has been readily treated with CCA with no significant loss in strength. Seasoning of logs prior to treatment requires particular attention in the wet tropical and sub-tropical regions of Queensland. Experimental and in service field tests have indicated excellent performance of CCA ...
L E Leightley
Efficacy of anhydrides as wood protection chemicals - II. Performance against soft rot fungi
1998 - IRG/WP 98-30174
Pine sapwood modified with various anhydrides and with butyl isocyanate was tested for its resistance to soft rot decay. Small stakes were exposed for 20 months in unsterile soil in a fungal cellar test.
Wood modified with butyl isocyanate performed better than any of the anhydrides tested, with a threshold level of protection (less than 3% weight loss) at 12% weight percent gain (WPG). Stakes ac...
S C Forster, M D C Hale, G R Williams
Are fungal cellar tests really necessary?
1989 - IRG/WP 2333
During the past decade the range of methodology used to evaluate wood preservative potential has significantly expanded. At the forefront of these new tools available to the scientist·is the fungal cellar. This technique, as currently applied, involves the exposure of treated and untreated samples to conditions of moisture and temperature which ensure optimum fungal attack. By comparison data wit...
J N R Ruddick
Biological performance of gypsum products containing borates
2000 - IRG/WP 00-30237
At suitable retentions borates have biostatic properties enabling them to be used for biodeterioration control in wood. They provide protection against decay fungi, mould, and termites, which are known to also attack gypsum products. Currently, many gypsum products contain added borates, which are used to improve physical and processing characteristics. Work examining the effect of borates at cont...
J L Fogel, J D Lloyd
Above ground performance of CCA-treated fingerjointed lumbe
1993 - IRG/WP 93-40003
Studs made from short lengths by finger jointing are becoming more commonly used in North America. Recently Forintek has received enquiries about the performance of such material in a treated form. Treated and untreated nominal 2x4 inch² spruce-pine-fir (SPF) studs exposed above ground for 12 years in southwestern British Columbia were evaluated for evidence of decay. Despite shallow preservative...
P I Morris, G E Troughton
Co-operative Field Experiment: Performance of preservative-treated timber: Report on condition of specimens after seven years installed in New South Wales - Australia
1986 - IRG/WP 3362
R S Johnstone
The performance of glue laminated railway ties after 40 years of service in the main line track
1989 - IRG/WP 2325
Two series of horizontally glue laminated ties made of a softwood body and topped with a hardwood lamination were creosoted and installed in 1947 in a tangent and a curved main line track. The tests are now 40 years old and the excellent condition of the ties of these two series suggest that a service life of 50-60 years can be expected....
J P Hösli, E E Doyle, C P Bird, T Lee
Monographic information on Paxillus panuoides (Fr. ex Fr.) Fr. (First draft)
1978 - IRG/WP 184
A Käärik
Performance of CCA treated Eucalyptus round ties
1985 - IRG/WP 3342
After 5.5 years of field exposure in the south of Brazil round Eucalyptus ties treated with CCA type A Oxide (OSMOSE K-33-A) preservative with retentions from 12 to 14 kg/m³ (0.75 to 0.873 PCF) (active ingredient basis) are performing very well. No decay or insect attack was observed in the 100 ties in test in real conditions of use; 10% of ties show incipient checking (what is a natural trend of...
V J Carlos, F R Niederauer, J P P Wehr
36 years of wood preservative tests in Tanzania
1992 - IRG/WP 92-3731
The performanee of major wood presevatives which are used widely commereially are given. These include creosote, CCA's and 5% Pentachlorophenol dissolved in heavy industrial diesel. Tests are conducted at three ecologically different using pine stakes. Results show that the striking performance of creosote and CCA's is noticeable at above 128 kg/m³ and 16 kg/m³ respectively....
K K Murira, P F Nangawe
Performance of surface-treated hardwoods and softwoods out of ground contact
1990 - IRG/WP 3592
A number of fungicides were tested as brush treatments for protection of southern pine, Douglas-fir, maple, and red oak against decay above ground. Cross-brace and L-joint test units were treated just before assembly and exposed from 3-10 years. Untreated Douglas-fir cross-brace units were not decayed at either the Mississippi or Madison, WI, site. Untreated red oak cross-brace units were not deca...
T L Highley
Co-operative research project on L-joint testing. Progress report to March 1988
1988 - IRG/WP 2315
Further sets of data received from CTFT (France), BAM (Germany) and PRL (UK) after 46-48 months exposure and STU (Sweden) after 22 months exposure are presented and discussed in conjunction with data reported previously. Colonisation and attack of the L-joints has progressed with increasing exposure period. The new data are generally in agreement with those presented previously and the major diffe...
J K Carey, A F Bravery
Comparative performance of pentachlorophenol and copper naphthenate in a long term field stake test
2000 - IRG/WP 00-30243
In this study the performance of copper naphthenate (Cu-Nap) and pentachlorophenol (Penta) treated pine stakes against decay and termite attack were compared at two test sites in Mississippi. Four different petroleum oils meeting AWPA Standard P9-A were used as carriers for these wood preservatives. After ten years exposure, the efficacy of Cu-Nap at a retention level of 0.05 pcf Cu was equivalent...
D D Nicholas, M H Freeman
Short term preconditioning of preservative-treated wood in soil contact in relation to performance in field trials
2000 - IRG/WP 00-20185
The effect of pre-exposure to primary colonising micro-organisms on preservative-treated wood, prior to a basidiomycete decay test, was determined by preconditioning in two soil types. Scots pine EN 113 blocks treated with 3 model systems (a triazole, a copper quaternary compound and a copper boron triazole) were leached according to EN 84 and subjected to 6 weeks and 8 weeks burial in either John...
S Molnar, D J Dickinson
Co-operative field experiment. Performance of preservative-treated hardwoods with particular reference to soft rot: Report of condition of specimens installed in Victoria, Australia
1978 - IRG/WP 3118
J Beesley
Proposals for a field experiment to determine the performance of preservative treated hardwoods with particular reference to soft rot
1975 - IRG/WP 342
It is proposed to treat a series of hardwood stakes in the UK and install them in different sites around the world. The stakes will include 3 reference species common to every site and 2 locally selected species. The hazard of termites should be avoided in order to limit the study to action of micro-organisms....
D J Dickinson
Ground contact performance of wood treated by the MSU process
1990 - IRG/WP 3609
Environmental concerns have prompted a renewed interest in accelerated fixation schemes for CCA-treated wood. Results from stake tests of southern pine (Pinus sp.) treated using a conventional Bethell cycle are compared with matched stakes treated using the MSU Process. The effects of adding boric acid to the preservative formulation are also discussed. Differences among test plots are discussed....
H M Barnes, T L Amburgey, R W Landers
Long-term performance of a "wax" type additive for use with water-borne pressure preservative treatments
2000 - IRG/WP 00-40159
Field performance results are updated for matched CCA treated decking boards with and without an emulsion water repellent additive incorporated with the initial pressure treatment. Decks have been exposured for over 9 years in Harrisburg, NC. Boards were evaluated for in-service and laboratory performance for water repellent efficacy, as well as additive loadings in the boards after this exposure....
A R Zahora
The leachability, biological resistance, and mechanical properties of wood (Pinus sylvestris L.) treated with CCA and CCB preservatives
1999 - IRG/WP 99-30207
Scots pine (Pinus sylvestris L.) specimens treated with CCA and CCB preservative solutions (1.0%) were subjected to several fixation processes and leached elements from the specimens were determined. In addition, the specimens exposed to different fixation temperatures were subjected to soil-block test using two brown-rot fungi and one white-rot fungus in order to investigate the effects of fixati...
S N Kartal
The performance of wood preservatives in soil-bed soft rot tests
1993 - IRG/WP 93-20007
Testing the efficacy of wood preservatives in soil is recognised as a fundamental part of the assessment of long-term wood protection in ground contact. Laboratory based tests can provide a hazardous environment in which a preservative can be challenged by a range of micro-organisms. This paper presents the results of tests carried out to investigate the performance of wood preservatives in a wet ...
G R Williams, S Caswell
Decay resistance of resin treated wood
1999 - IRG/WP 99-30206
Selected natural resin systems were evaluated for their potential as wood protecting agents according to standard test procedures. As indicated by the European standard EN 599 both a Basidiomycete test according to EN 113 and a ENV 807 soil bed test were carried out. Six resin treatments were tested using 3 concentration or treatment levels. Using the biocidal activity criteria as usually applied ...
J Van Acker, A J Nurmi, S M Gray, H Militz, C Hill, H Kokko, A O Rapp
Evaluation and approval of wood preservatives. Unification of European requirements
1988 - IRG/WP 2310
This paper reviews the current activities within the European Homologation Committee for Wood Preservatives (EHC) towards unification of the requirements on evaluation and approval of wood preservatives in Western European countries....
J Jermer
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
Requirements for hosting the Secretariat of IRG
2006 - IRG/WP 06-60227
IRG Secreteriat