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The 1999-2000 annual report for the IRG - Wood Preservation in Egypt
2000 - IRG/WP 00-40188
The wood destroying insects in Egypt are belonging to several families of Coleoptera, Lepidoptera and Isoptera. Imported woods are treated by The Agricultural Quarantine or the authorized companies. The materials used for protection as pre-treatment are the same of the treatment. They are Bromide methyl, copper or fluoride salts, organo-phosphorus compounds, pyrethroides, creosote or creosodial. Any preservative should be evaluated by the Ministry of Agriculture before recommendation. Of the preserved woods are Lumbers, sleepers and poles, woods used in constructions and furniture as well. The woods used in furniture, constructions or woodworks are mostly imported from Sweden, Russia, Finland or Korea. Several kinds of woods are imported as Picea sp., Pinus sp., Phagus sp. Local woods used are limited in kinds and amount, as Casuarina sp., Eucalyptus sp., Ficus sp., Acacia sp. Treated woods are potentially increasing in use. There are neither restriction for the use of treated woods, not any regulation concerning the desposal of these woods.
S I M Moein


Treatment of wood by diffusion of salts
1976 - IRG/WP 368
A brief survey is given on the treatment of wood by diffusion of salts. The compounds used for this process, mainly boron and fluorine compounds, are mentioned and the factors influencing diffusion described. The main pre-condition is a high moisture content of the wood of above 40%. Fields of application are fresh roundwood, remedial treatment of poles and sleepers, preservation of posts and especially of building and other sawn timber. The treatment of building timber by spraying, dipping or soaking should be followed by the diffusion process which may provide, in a simple and cheap way, deep penetrations of salts into the wood including species refractory to pressure methods.
G Becker


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


Health aspects concerning the use of bifluorides in wood
1981 - IRG/WP 3173
An attempt has been made to find a correlation between the quantities F¯ and HF present among other ions in an 'Improsol' solution consisting of NH4F.HF and KF.HF, the quantity absorbed by the wood from this after immersion and the toxicological effects of this treated wood when it is used in rooms destined for the residence of people or animals or for the storage of foodstuffs.
H F M Nijman


Effects of various preservative treatments on the mechanical and physical properties of plywood
1993 - IRG/WP 93-40007
The technical properties of plywood are related to both the intrinsic characteristics of its composing wood species and the quality and performance of the glue bond which acts as an interface between veneer sheets. Consequently mechanical and physical testing and glue bond strength analysis offer an appropriate means for studying the effect of preservative treatments on the overall quality of plywood. A range of boards was treated with waterborne and oilborne preservatives. Changes in modulus of elasticity, modulus of rupture and tensile strength were noted as well as variations in physical properties. Analysis of the glue bond strength was done by shear strength testing and determination of the amount of wood failure after different ageing procedures.
J Van Acker, M Stevens


Preliminary results of investigations on screening test of chemical compounds suitable for the preservation of lignocellulosic materials against biodeterioration
1976 - IRG/WP 262
This paper investigates the possibilities of reducing the time needed for the determination of the effectiveness of chemical compounds from the point of view of their eventual application to lignocellulosic materials for preservation against decay and soft-rot.
K Lutomski, S S Neyman


Absorption of inorganic salts solutions. Retentions of inorganic salts. Fire retardants
1990 - IRG/WP 3625
The study aims evaluated the impregnation capacity using fire retardants on woods with differents densities. At the same time, impregnation with several fire retardant salts were carried out in order to obtain their absortion and retention in wood.
A Garcia, J Navarro


The use of bifluorides-diffusion in remedial treatments
1983 - IRG/WP 3256
A description is given about the experience to date of a 14 years' development to bring bifluorides-diffusion from laboratory evaluation to commercial service application. The described treatment is an adjunct to good design and not a replacement for it. The process is also used with an injection method for the remedial treatment of premature decayed external joinery.
H F M Nijman


Testing of alkylammonium compounds
1981 - IRG/WP 2152
Following laboratory soil block tests which showed that Bardac 20 possessed a fungicidal threshold similar to that of chromated copper arsenate, treated ponderosa pine sapwood stakes were installed in a field test site near Vancouver, Canada. Two years after installation all the stakes show signs of fungal degradation. Seven stakes have been removed from the test due to total loss of strength after only two years, and many others are near failure due to extensive decay. It may be concluded from this study, that under the conditions of the test, Bardac 20 has failed to prevent wood-destroying fungi from decaying the stakes. Further investigation of treated "check" stakes and failed field tested stakes has revealed an uneven distribution of the chemical in some stakes treated to low retentions.
J N R Ruddick


The influence of previous anti-blue-stain preservative treatments on the fixation of CC in spruce
1997 - IRG/WP 97-30134
Freshly cut and kiln dried spruce boards were treated with 4 different anti-blue stain preservatives (ABP). After a period of 10 days allowing the samples to dry and fixate, the samples were treated with CC (chromium, copper formulation) using a vacuum pressure cycle. After impregnation the wood was steam fixed. A submersion leaching test showed differences in the leachable quantity of copper and chromium. When related to the retention of both salts after impregnation, no differences could be found between samples previously treated with anti-blue-stain preservatives and untreated samples. However, the retention of CC diminished significantly by application of quaternary ammonium compounds.
M Van der Zee, W J Homan


Diffusion of bifluorides and borates from preservative rods in laminated beams
1991 - IRG/WP 3644
Laminated beams from spruce, pine and larch were treated with two preservative rods, based on bifluorides and octaborate respectively. After 3 and 6 months placed in different climates (65% r.h., 100% r.h., water) the diffusion of the active ingredient was measured. After the 6 months period, the diffusion of the bifluorides was, in all species, ca. 5 times larger than the diffusion from octaborate rods. The bifluorides were not hindered by the glue-lines. The diffusion of the borate was poor, mainly perpendicular to the grain and was hindered by the glue-line.
H Militz


The preliminary evaluation of selected sulfonium salts for use in wood preservation
1984 - IRG/WP 3278
Five sulfonium compounds, including two sulfonium methosulfates, one sulfonium bromide and two amphoteric sulfonium propanesulfonates, were prepared in crude form and subjected to various biocidal screening tests. A rapid screening test in which treated Pinus radiata pulp pellets were exposed to one of three wood-decaying fungi growing on malt agar revealed that dodecyl dimethyl sulfonium methosulfate had an inhibiting effect comparable to that of lauryl dimethyl benzyl ammonium chloride (benzalkonium chloride). The remaining sulfonium salts gave no fungal inhibition in this test. Both dodecyl- and decyl dimethyl sulfonium methosulfate gave a positive response in a screening test for insecticidal activity. However, rapid insect recovery indicated detoxification or excretion of the test chemicals. Dodecyl dimethyl sulfonium methosulfate was also screened as an anti-sapstain treatment with encouraging results. Further work is now in progress to explore the potential wood preservative capability of certain sulfonium and sulfoxonium salts.
D V Plackett


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 organic anions or copper (ll) and zinc complexes on their biological activity against wood decay, staining and mould fungi. The fungicidal value of new compounds for Coniophora puteana ranged from 0.64 kg/m3 to 2.2 kg/m3. Aspergillus niger turned out to be the most resistant fungus to the action of modified IC and QACs, whereas Sclerophoma pityophila was effectively inhibited by the examined salts. The performed soil-block tests showed that the IC and QAC were leached from the experimental wood in conditions of contact with moist soil and revealed their fungal detoxification by mould fungi, especially by Gliocladium roseum. Observations made using the scanning electron microscope of the colonization and decay of treated wood by mould fungi confirmed tolerance of mould fungi to QACs.
J Zabielska-Matejuk, W Wieczorek


Interaction mechanisms of F/Cr/As/B type preservative and wood
1981 - IRG/WP 3183
The paper reports results of investigations on the fixation of the components of a F/Cr/As/B preservative in wood and its lignin and cellulosic components.
N Ermush, I Andersone


Performance if internal remedial treatments to arrest fungal attack in poles and large timbers
2018 - IRG/WP 18-40834
Internal remedial treatments have been used to arrest internal fungal attack in utility poles and other large timbers. Water diffusible systems and volatile fumigants have both been used for this purpose. While both work, it is important to understand the performance attributes of each system. This paper reviews the literature on both systems and makes recommendations for future research.
J J Morrell


The use of plastic meshes in soft rot monoculture testing
1990 - IRG/WP 2353
Plastic meshes were introduced between the wood blocks and agar medium in a miniaturised soft rot monoculture test in order to minimise transfer of the preservative from the wood and mineral salts from the agar. Although several different sizes and types of mesh were used and the blocks were wetted up to an appropriate moisture content for soft rot attack the amount of decay was substantially reduced compared with the controls. Addition of mineral salts to the wood blocks in similar quantities to those in the agar aided decay but did not provide suitable conditions for maximum loss in weight.
S M Gray


Remedial treatment of joinery. Comparison of distribution of organic solvent preservative and ammonium bifluoride
1978 - IRG/WP 3115
It is some years since it was recognised in the United Kingdom that there was a problem of premature decay in untreated external joinery. Consequently, recommendations for preservative treatment were made by the Building Research Establishment, Princes Risborough Laboratory. In addition, the National House-Building Council has also included the preservative treatment of external joinery in its requirements. Thus, a large proportion of external joinery manufactured in the U.K. is now preservative treated, mainly in double vacuum impregnation plants. There still remain, however, relatively new buildings where preservative treatment has not been specified and where fungal decay is a problem. Decay occurs most frequently in the lower horizontal members such as cills, and the lower rails of opening lights. The damage is often most severe at the joints, where entry of water is facilitated by exposure of end grain. In some circumstances such as in Local Authority buildings where some of the more exposed joinery has already decayed, it has been considered economic to treat the remaining sound or near-sound joinery in situ in order to prevent future attack and to arrest any slight decay that may already be present. This treatment is normally applied by injecting organic solvent preservative under pressure in the region of the joints and where considered necessary along the lower horizontal member. As an alternative method of treatment, we have investigated the possible use of ammonium bifluoride, since diffusion of gaseous hydrogen fluoride may be expected to penetrate more extensively into wet timber than organic solvent preservative. The work described below was carried out in order to assess the comparative penetration of fluoride and organic solvent preservative in redwood (Pinus sylvestris).
J M Taylor


Fluoride woodpill
1987 - IRG/WP 3431
Decay problems of spruce joinery in the Netherlands in the 1960's and 1970's led to the introduction of preservative treatment. Because of the known penetration difficulties with Spruce, the results of the treatments were not always successful. The fact that the decay was found only in the joints led to development of the philosophy of "local preservation" of the joints in remedial and preventative treatments, like preservative injections or use of rods and capsules containing preservatives. However the diffusion of the preservatives used in most of these systems is often poor in spruce. Because Spruce joinery dip-treated with bifluorides showed good penetration and protection, a pill consisting of a hydrophylic polymer and bifluorides was developed by TNO. Various laboratory tests carried out with this pill have confirmed good penetration of the bifluorides in the wood and activity against decay fungi.
J W P T Van der Drift, K J M Bonsen


Determination of total fluoride in preservative-treated wood by ion selective electrode, without steam distillation
1996 - IRG/WP 96-20086
An analytical method was developed to determine total fluoride in wood treated with aqueous fluoride or borate-fluoride formulations. Ground wood was mixed with 60% sodium hydroxide solution and oven-dried overnight before furnacing at 600°C. The cool fused product was dissolved in warm water before adding a powerful complexant/buffer solution containing sulphosalicylic acid and EDTA. Fluoride was measured by ion-selective electrode (ISE) against appropriately matrix-matched calibration standards containing 1, 10, or 100 ppm F. The method compared favourably with two alternatives; one employed the time-consuming distillation step included in the AWPA A2 1994 method, with a titration finish, and the second employed a double fusion and ISE finish, using TISAB buffer. The chosen buffer system exhibited better capacity than TISAB to complex excesses of model interferant Al. B and Si were also accommodated. Recovery from spiked Eucalyptus maculata (at 0.05-0.5% m/m F) was 94-96%. Precision when analysing Alstonia scholaris containing 0.35% m/m F was about 2%. The method enables better throughput than the AWPA A2 94 method
M J Kennedy


The use of a physical field model to study the effects of remedially treated timber on the growth of perennial ryegrass (Lolium perenne) and rye (Secale cereale), and the accumulation of toxic preservative constituents in Lolium perenne
1995 - IRG/WP 95-50040-02
Low cost laboratory model systems can be used to give relatively rapid indications of the environmental effects of preservative treated timber in soil contact. This paper details the effects of remedially treated timber on the growth of crops of Lolium perenne and Secale cereale seeded on soilbeds of different texture in close proximity to remedially treated creosoted pole sections. Lolium perenne sward samples were subjected to chemical analysis for fluoride and chromium content to identify bio-accumulation of these toxic preservative components. Significant but variable reductions in the dry weight yields of Lolium perenne samples were found in conjunction with increased fluoride and chromium contents, together with significant reductions in the density of Lolium perenne swards. The difference in soil texture however was found to be a more significant influence on the growth of Secale cereale than the presence of treated timber. Secale cereale plants within a crop canopy established on the lighter textured soil were characteristically larger and more numerous than plants from canopies on heavier soils. Results are discussed as part of an overall environmental assessment of the remedial treatment and in terms of the suitability of the physical field model as a testbed for such plant studies.
D C R Sinclair, G M Smith, A Bruce, H J Staines


Leaching and fixation characteristics of chrome-copper-fluoride-zinc (CCFZ) treated wood
1996 - IRG/WP 96-30096
The leaching characteristics of radiata pine sapwood blocks treated with CCFZ were evaluated by the AWPA standard leaching test. The rate of fixation of the preservative components in CCFZ treated radiata pine were also evaluated by quantitative analysis of solution expressed from the treated wood. Both leaching and fixation characteristics of CCFZ were compared with CCA-Type C treated wood samples. The permanence of CCFZ is excellent and comparable to that of CCA-Type C, and the rates of CCFZ fixation were similar to those found for CCA-Type C. These results suggest that CCFZ has a potential as alternative preservative for the replacement of CCA-Type C.
Gyu-Hyeok Kim, Jong-Bum Ra


Summaries of two Russian papers received from Professor Dr. D.A. Belenkov and V.A. Seletskaya of the Ural Forest Engineering Institute, Sibirsky Trakt, 37, Sverdlovsk, USSR, on the toxicity to Coniophora cerebella of salts of hydrofluoric acid and some fluoroborates
1977 - IRG/WP 298
1) Evaluation of the toxicity of some salts of hydrofluoric acid against the house cellar fungus (Coniophora cerebella Schroet) Data are presented on the method of probability evaluation of the toxicity of the fluorides of sodium, ammonium, potassium, zinc and iron. On the retention of fluorine in wood all salts, except iron, possess practically equal toxicity at the standard level of the probability of the protection of the wood - 0.95 . There is good agreement between the analytically and graphically determined dose level. Evidence is given for dose variabitility, probabilities of wood protection at 0.5 and 0.95, the curve of efficacy - activity and the construction of the empirical probit graph. 2) Investigation of the toxicity of some borofluorides towards the house cellar fungus Probability evaluation of the toxicity of borofluorides against the cellar fungus, and probit analysis evidence show that toxicity decreases in the sequence sodium borofluoride, copper borofluoride, tributyltin borofluoride. The effectiveness of protection method is able to evaluate the amount of fluorine and boron required in the wood.
C Grant


Assessment of dehydrogenase activity, fluoride content and total chromium content of soil profiles exposed to preservative treated wood within a model system
1993 - IRG/WP 93-10015
The development and prospective use of a closed model system to facilitate study of a number of indicators of environmental impact of wood preservatives laboratory conditions has been described (IRG/WP/2395-92). Chemical analysis of leachate samples collected from drained soil profiles containing creosoted pole sections remedially treated with a chromated fluoride preservative indicated small increases in fluoride and chromium concentrations. This paper details measurement of dehydrogenase activity and chemical analysis of soil samples recovered from the surface layers of the model soil profiles adjacent to treated pole sections. Reduced levels of dehydrogenase activity were associated with increased soil concentrations of leached preservative components and lower organic matter content. Findings are discussed as part of an assessment of environmental impact of the remedial treatment in the field
G M Smith, D C R Sinclair, A Bruce, H J Staines


Effectiveness of copper/chromium salts as wood preservatives against Limnoria tripunctata Menzies in laboratory tests
1977 - IRG/WP 431
During the last joint meeting of IRG and COIPM a co-operative programme of tests with copper/chromium salts as wood preservatives against marine borers was discussed and agreed. In this connection the results of a laboratory test in the BAM with Limnoria tripunctata Menzies will be of interest. But as the respective paper is written in German (H. Kühne; G. Becker: Laboratoriumsversuche über die Wirkung kupferhaltiger Schutzsalzgemische auf die Holzbohrassel Limnoria tripunctata Menzies) (Material u. Organismen 5 (1970) No 4, 307-319) a comprehensive summary is given in English for IRG-COIPM members.
H Kühne


Initial results and observations of a model system to assess the efficacy and environmetal impact of preservative treated wood
1993 - IRG/WP 93-50001-02
The development of a closed model system for the laboratory assessment of the efficacy and environmental impact of a chromated fluoride remedial treatment for creosoted distribution poles has been described (IRG/WP/2395-92). The model consists of a precipitation apparatus above a treated pole section positioned in a soil profile from which leachate was collected via a series of simulated field drains. Chemical analyses of leachate and soil provided data indicating movement of toxic preservative constituents from the treated pole section to the model environment. These data were complemented by physical and chemical analysis of a sward of perennial ryegrass supported by the soil profile. This paper reports initial results and observations in terms of the models' suitability for assessment purposes. The advantages of the model system over traditional field studies are discussed.
D C R Sinclair, G M Smith, A Bruce, H J Staines


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