Your search resulted in 224 documents. Displaying 25 entries per page.
Non-destructive detection of the presence and behaviour patterns of wood-destroying insects
1988 - IRG/WP 2302
An apparatus, designed for the automatic recognition of the presence and of specific behaviour patterns of wood-boring insects, is introduced. From a wood sample, a mixture of noise and action induced substratum vibrations is picked up, amplified, filtered and translated into a sequence of computer-readable numbers which are passed to a microcomputer-based signal-pattern-recognition. If an incoming signal-pattern matches one of a behaviour-specific reference-pattern, the corresponding behaviour is transferred to the systems output. This technique is suitable for a fast, reliable and non-destructive recognition of infestation as well as for a quick valuation of new insecticides in screening by dosis-time-efficacy.
Long-time efficacy of some soil termiticides tested according to “Modified Ground Board Test”
2018 - IRG/WP 18-10935
Field trials of efficacy of soil termiticides available in Thailand were started back in the 1980s at four different locations representing different unique weather types of the country. The method used in the trials (Modified Ground Board Test) is the compulsory test for every soil termiticides aiming to be registered for termite control in Thailand. The ongoing record reveals that some particular formulations of Bifenthrins, Fipronils, Imidacloprids and Chorantraniliprole continue to perform well after nine years application.
C Vongkaluang, K Charoenkrung, N Same Rain
Preliminary study of the fungicidal and structural variability in copper naphthenates and naphthenic acids
1996 - IRG/WP 96-30114
Copper naphthenates, an oil-borne wood preservative listed by the American Wood-Preservers' Association (AWPA), is manufactured by complexing copper(II) with naphthenic acids. Prior to AWPA listing as a wood preservative, field experiments showed that copper naphthenates generally had good stability and were active against wood-destroying organisms. Recently, however, there have been reports of some copper naphthenate-treated poles rapidly failing. One possible explanation for the varying effectiveness could be that the structure, and resulting biological activity, of the naphthenic acids used to make copper naphthenate may vary. To test this hypothesis several naphthenic acids and copper naphenates were obtained and their fungicidal activity against three wood-destroying fungi measured. In addition, the chemical structure of the naphthenic acids were examined by proton- and carbon- NMR. Different activities were observed, especially against a copper-tolerant fungus. Some apparent correlations were seen between the fungicidal activity and chemical structures for the few samples studied.
T Schultz, D D Nicholas, L L Ingram Jr, T H Fisher
Proposed methodology for the assessment of safety indexes
1990 - IRG/WP 3562
Safety Indexes (SI)s are developped on the same concept as Efficacy Indexes (EI)s: EIs are retentions of wood preservatives (percentages of the critical values "efficacy") which are presumed efficient for a given biological class of risk. In the same way, SIs are retentions of wood preservatives (percentages of the critical values "safety") which are taken as acceptable for human health and the general environment. EIs and SIs as well are derived from different types of bioassays and related to objectives of quality which may be either regulatory or harmonized within the programmes of the Standard Committees (CEN TC/38 for example). Critical Values are characteristics of wood preservatives; EIs and SIs are characteristics of treated wood; they vary with the different classes of risks.
Copper naphthenate performance: A new way to look at old data
2000 - IRG/WP 00-30215
Although copper naphthenate has over a 50-year test history, it is still considered as a "new" preservative in the United States when it is used for utility poles. It has also been extensively used in remedial treatments for poles and has considerable retail or over-the-counter sales. The test history includes a number of different tests and a rationale for evaluating this data and comparing the performance of copper naphthenate to other common pole preservatives is presented. Thus, the efficacy of copper naphthenate can be easily summarized.
C R McIntyre
The evaluation of synergistic effects of chemicals on fungicidal efficacy in crossed-paper tests
1991 - IRG/WP 2383
The mixing effects of wood preservatives were evaluated using the crossed-paper technique. Two filter paper strips (0.7 x 8 cm²) were treated by soaking with different chemicals [fungicides, a termiticide (chlorpyrifos or phoxim), a surface-active agent, a synergistic agent, and a stabilizer], and placed at right angles to each other on a fully grown mycelial mat of a test fungus in a Petri dish. When the four organoiodine fungicides were incorporated with chlorpyrifos or surface active agent, only 3-iodo-2-propynyl butyl carbamate (IPBC) showed the desirable synergistic effect against every wood-decaying fungus tested. Other fungicides did not always tend to produce the synergistic effect with the addition of a surface active agent. 4-Chlorophenyl-3-iodopropargyl formal (IF-1000) appeared to indicate an undesirable antagonistic effect when mixed with either chlorpyrifos or a surface active agent. 3-Bromo-2, 3 diiodo-2-propenylethyl carbamate (EBIP) did not show any synergistic action by mixing with chlorpyrifos and/or a surface active agent, although the fungicidal enhancement was induced satisfactorily by mixing the fungicide with chlorpyrifos, a stabilizer and/or a synergistic agent, especially against Tyromyces palustris and Coriolus versicolor. Similarity of the results obtained in the present investigation and in the previous laboratory decay tests leads to the conclusion that the crossed-paper technique is suitable for the evaluation of the mixing effect of chemicals on fungicidal efficacy.
Dong-heub Lee, K Tsunoda, M Takahashi
Protocol for evaluation and approving new wood preservative
1985 - IRG/WP 2159
M E Hedley, J A Butcher
Boron treatments for the preservation of wood - A review of efficacy data for fungi and termites
1994 - IRG/WP 94-30037
Boron treatments have been used for many decades for protection of timber from biological attack and also as a fire retardant treatment. In recent years there has been an increased interest in boron treatments as an option for protection of structural timbers' e.g. timber framing used in termite risk areas. This paper reviews efficacy data for both fungi and termites relevant to this end-use.
J A Drysdale
A collaborative test to determine the efficacy of polyurethane coatings on wood samples exposed in the marine environment
1984 - IRG/WP 4113
Aims are: a) to determine the effectiveness of elastomeric polyurethane as a protective coating against marine wood boring animals in a range of tropical and tempreate sites; b) to compare the adhesion of polyurthane coatings on different wood species exposed in seawater; c) to record the severity of attack in failed samples and to identify the causal marine organisms.
R A Eaton
1981 - IRG/WP 1138 (+ Addendum)
The stages of growth of soft-rot fungal hyphae in birch cell walls has been studied using transmission electron microscopy. These observations are compared with time-lapsed cinemicrographic studies on infection and cavity development within wood cell walls which show a start-stop hyphal growth pattern. The fine structure of hyphae during each stage of the decay process shows that hyphae penetrating the wood cell wall have dense, granular cell contents and few recognisable cell organelles. As cavities widen and the hyphae within them increase in size, a hyphal cell wall is laid down, septation occurs and cell organelles are present. At maturity, cavity hyphae become vacuolate, slightly distorted in form.
M D C Hale, R A Eaton
Effect of protective additives on leachability and efficacy of borate treated wood
2002 - IRG/WP 02-30290
Borate preservatives have been used extensively in many countries as an effective means for protecting wood against fungal and insect attack especially in interior environments. Under exterior conditions, borate compounds have a main disadvantage as they can be leached from treated wood as a result of their water solubility. In this study, we compared the potential of different additives for reducing the leachability of boron preservatives from treated wood. Scots pine sapwood (Pinus sylvestris) and poplar (Populus trichocarpa x deltoides) test samples were vacuum treated with 1 % BAE (Boric Acid Equivalent) disodium octaborate tetrahydrate (DOT) solutions containing various additives e.g. glycerol/glyoxal, polyvinylpyrrolidone (PVPY), a commercial resin compound and a commercial water repellent. The European Standard EN 84 was used as a leaching test for both coated and uncoated specimens. The results of chemical analysis of leachates taken at different periods showed that the use of protective additives reduces the boron leachability. The glycerol/glyoxal additive applied to treated pine sapwood showed the best performance. The percent of boron retained in uncoated pine sapwood was 26% while coated samples still retained 45% after 14 days of intense leaching. Similar tests on poplar revealed 19% and 34% for uncoated and coated samples, respectively.This represents a gain of 20 to 25% compared to pure DOT treated specimens of both wood species. Preliminary biological tests were carried out on malt agar using a miniblock technique for uncoated pine sapwood and beech, with Poria placenta and Coriolus versicolor, respectively. After six weeks of exposure to fungal attack all boron protective systems tested proved their effectiveness, as none of the test samples exhibited a mass loss exceeding 4%. The reference 1% BAE without protective additives showed an average mass loss of 15%. Finally, test data are reported of standard EN 113 testing in view of a further evaluation of the biological efficacy of combined DOT-additive treatments.
A Mohareb, J Van Acker, M Stevens
Local preservation with difluoride pills: Life-time of preservative
1998 - IRG/WP 98-40127
A brief history of the situation in the Netherlands with respect to the preservation of joinery is given. Already in the eighties in the Netherlands many spruce window frames were treated with difluoride pills. One of the possible disadvantages of this kind of diffusing preservatives is the high leaching rate found in laboratory situations. The leaching rate in practice is influenced by many factors of which the condition of the paint systems and the condition of the glue in the joint are the most important. In this research the difluoride content in wood was analysed in samples which were taken from several buildings. An estimation of the remaining difluoride content leached is given. Related to these figures the remaining life of the protecting agent can be calculated. The results show that even in situations with open joints of paint damage the remaining amount of difluoride is still very high after 10 years. This suggests that in practice the leaching of difluorides is of minor importance.
W J Homan, C Blom, B W Holleboom
Determination of the preventive efficacy against wood destroying basidiomycetes fungi, EN V 839 - CEN/TC 38 WG 9
1993 - IRG/WP 93-20015
The WG 9 of CEN TC/38 has presented to EC a mycological test to assess efficacy of preservatives applied by surface process. This method is now an experimental standard (EN V 839) which has to be approved by the different european delegations. The following paper is not the standard as it has been proposed but is a presentation of the principle of the method. The experimental standard specifies a laboratory method of test which gives a basis of the assessment of the preventive action of a wood preservative when applied as a surface treatment against Basidiomycetes fungi. This method is applicable to formulations of preservatives in a ready to use form (organic formulations, organic water-dispersible formulations, water-soluble materials). Series of susceptible wood species specimens are treated on longitudinal faces whith the preservative in test using brushing as surface procedure. Test specimens are then exposed by an intermediate mesh to feeder blocks infestedby pure culture of Basidiomycetes fungi in sterile conditions and penetration of fungi is assessed on cross section sawn in the samples at the end of the test.
A wood preservative for the future: Copper dimethyldithiocarbamate
1994 - IRG/WP 94-30045
The development of a new wood preservative, copper dimethyl-dithiocarbamate (CDDC) is reviewed in this paper. CDDC is formed in situ by dual pressure treatments. Laboratory and field efficacy trials, physical and chemical properties of the preservative solutions and treated wood, and plant handling characteristics of the system are examined.
D K Stokes, M H Freeman, T L Woods, R D Arsenault
1983 - IRG/WP 3268
Errata to Document No: IRG/WP/3276
1984 - IRG/WP 3285
W E Conradie
Water-based wood preservatives for curative treatement of insect-infested spruce constructions
1998 - IRG/WP 98-30171
On laying down sanitation measures for wooden constructions infested by wood boring insects, we must take into account static risks for the construction - and, thus, for the security of the user - as well as risks for humans and environment due to the chemical preservative compounds of the treated wood. Analyses on many roof constructions made with spruce (Picea abies L.) have revealed that Hylotrupes bajulus L. and Anobium punctatum De Geer have not the significance given to them for decennies. That often allows to replace solvant-based with water-based wood preservatives in old buildings, for the protection of humans and environment. Therefore, a method has been developed in Switzerland for testing wood preservatives with delayed curative efficacy against the house longhorn beetle. Like the European Anobium Standard EN 370 this method intends to prevent the emergence of Hylotrupes beetles. Laboratory tests with diverse water-based wood preservatives available on the market in Switzerland have shown that particularly boron and benzoylphenylurea derivatives containing products get a sufficient penetration in the wood and prevent the emergence of the beetles.
E Graf, P Manser, B Lanz
Microcapsule formulation of fenitrothion as a soil termiticide
1991 - IRG/WP 1478
The efficacy and the mode of action of a microcapsule formulation of fenitrothion against Coptotermes formosanus Shiraki were investigated. The physicochemical property that this formulation does not allow the active ingredient to diffuse through the capsule wall contributed to a long lasting efficacy and safety for the men spraying. The residual effect of the fenitrothion microcapsule in soil was revealed as well as that of chlordane in the laboratory test. It was clarified that the transmission of poisoning through the worker's self- and mutual grooming behavior contributed to the efficacy of this formulation. And it was suggested that the transmission of poisoning of fenitrothion through mutual grooming led to the collapse of a colony.
H Teshima, T Itoh, Y Abe
The effect of treatment method on CCA efficacy in Corsican pine
1992 - IRG/WP 92-3723
As part of a study into the influence of application method on preservative efficacy Corsican pine (Pinus nigra) samples (50 x 50 x 400 mm³) were treated with a CCA formulation using Bethel, Steam/Bethel or Lowry processes. Full penetration of the preservative at a gross level was confirmed using a copper disclosing reagent. The preservative was allowed to fix and then samples were converted into mini-blocks (30 x 10 x 5 mm³) to produce decay test samples from various locations within the larger samples. After leaching, sets of replicate mini-blocks were exposed to the decay fungi Coniophora puteana FPRL 11E, Coriolus versicolor FPRL 28A, and Chaetomium globosum FPRL S70K. Equivalent sets of leached blocks, were analysed using atomic absorption spectrophotometry to determine preservative concentration and balance. The results of this study have been used to assess the effect of preservative application method on CCA efficacy. They also indicate how treatment method affects the distribution of the active elements of the preservative throughout the treated wood.
P R Newman, R J Murphy
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 acetylated to 15% WPG did not give complete protection against soft rot. Stakes modified with alkenyl succinic anhydride showed increasing resistance to soft rot with WPG up to about 10% WPG, above which no further improvements were evident. Succinic anhydride and phthalic anhydride treated stakes showed little or no noticeable protection.
S C Forster, M D C Hale, G R Williams
Radio frequency heating times for sterilization radiata pine solid piles
2017 - IRG/WP 17-40815
In this work was sterilized wood packaging material of radiata pine, stacked as solid piles without stickers, for determining the heating times using radiofrequency treatment. The experiments were performed in a radio frequency semi-industrial equipment. The results showed that the radio frequency heating times increases with wood volume and that radio frequency treatments were faster than conventional vapour heat treatment.
H Esquivel, V Sepúlveda, J Torres, L Salvo, R A Ananías
Testing of termiticides in soil by a new laboratory method with regard to Phoxim for replacement of chlorinated hydrocarbons
1986 - IRG/WP 1292
In comparison to chlorinated hydrocarbons insecticides of the compound classes organophosphates, carbamates and pyrethroids were tested according to an earlier described soil-test in the laboratory. The following termite-species were used: Heterotermes indicola, Reticulitermes santonensis and in addition Reticulitermes flavipes, Reticulitermes lucifugus, Reticulitermes speratus and Coptotermes formosanus (Rhinotermitidae). The method gives reliable results. Criteria for evaluation are mortality and penetration of the termites into the treated soil. According to this test organophosphates, specially phoxim, have a good potential to replace chlorinated hydrocarbons.
Tentative method of testing wood preservatives against blue staining
1977 - IRG/WP 259
The blue stain of sawn wood is still a real problem in Poland. Although a preservative based on sodium orthophenylphenoxide has been introduced into sawmill practice, and the technology of wood protection developed with it, new information has been obtained concerning blue stain in wood material destined for export. In order to select new chemicals or to improve the effectiveness of the ones in current use it is necessary initially to carry out laboratory tests of the prepared chemicals to determine their efficiency.
E Tarocinski, O Lewandowski, M H Zielinski
Time dependent over-uptake of etherificated melamine resins
1998 - IRG/WP 98-40109
Waterbased methanol-etherificated melamine-formaldehyde resins can increase the fungal resistance of the treated wood though they are known to be non-toxic. Therefore melamine-resins are at the present an object of research activities of European projects and of some companies. The paper highlights the importance of quoting the duration of the diffusion when immersed in the treating solution, as major differences in the effectiveness against fungal attack can be obtained by extending the diffusion period. This paper also critically reviews the practice of referring the concentration of the solutions used for impregnation to a fixed solids content of this type of resins.
D Lukowsky, R-D Peek
Efficacy of some extractives from Pinus heartwood for protection of Pinus radiata sapwood against biodeterioration. Part 1: Fungal decay
1995 - IRG/WP 95-30072
Chemical compounds thought to contribute to the natural durability of heartwood of Pinus spp. were either chemically synthesised in the laboratory or extracted from the heartwood of Pinus elliottii or Pinus caribaea. These compounds included the stilbenes, pinosylvin and its mono- and di-methyl ethers, and the flavonoids, pinobanksin and pinocembrin. Small blocks of Pinus radiata sapwood were impregnated with methanolic solutions of pure compounds or heartwood extracts, to a range of retentions extending above and below the concentration of each compound known to occur in the heartwood of Pinus spp.. Fungicidal efficacy of these compounds has been evaluated by exposure of treated blocks to pure cultures of a white and a brown rot, in addition to an unsterile soil test.
M J Kennedy, J A Drysdale, J Brown