Your search resulted in 67 documents. Displaying 25 entries per page.
Influence of sampling on the composition of test solutions
1985 - IRG/WP 2235
For four commercial products of CCB-salts the influence of the kind of sampling on the composition of test solutions has been tested. For each product several 5 g samples have been taken at random, after careful mixing the content of each bottle, and after grinding the whole content. With each sample a 5% test solution was made and analyzed on the content of chromium, copper and boron. Altogether 111 solutions were investigated. The results demonstrate, that an at random sampling gives large variations in the composition of the various test solutions and only a grinding of the whole content of a bottle to a fine powdered product ensures a constant composition of test solutions.
H Willeitner, K Brandt
Progress report on co-operative research project on L-joint testing
1983 - IRG/WP 2192
A F Bravery, D J Dickinson, M Fougerousse
Biological screening assays of wood samples treated with creosote plus chemical additives exposed to Limnoria tripunctata
1980 - IRG/WP 408
Laboratory methods for exposure of treated wood coupons to Limnoria tripunctata are described. Chemical additions to creosote were screened using this method. Three pesticides, Endrin, Kepone, and Malathion proved particularly effective. The addition of varying percentages of naphthalene to creosote using several treatment methods are currently being assayed. Results to date show that the coupons treated by the empty cell method have better performance than those prepared by the toluene dilution method. The naphthalene coupons treated by the full cell method show no attack after six months' exposure.
B R Richards, D A Webb
Comparison of cubic and plug samples for preparation and data assembly in permeability study
2000 - IRG/WP 00-20197
In order to determine if plug experimental samples (PES: 30 x 15 mm2 diameter) could be used for inspection of wood permeability characteristics, radial and longitudinal flow directions were prepared according to either PES or cubic experimental samples (CES: 100 x 20 x 20 mm3) from the sapwood zone of Sitka spruce and treated by tanalith-C according to full-cell process. Results from the two preparation techniques agreed in the test to determine the mean percentage of void volume filled by liquid both radially and longitudinally, while the preparation process (i.e. machining, sealing, etc.) of the experimental samples and the period of the data collection was quite longer in CES than that for PES in either flow direction.
Coding scheme for samples for IRG world-wide co-operative field experiment
1975 - IRG/WP 360
Each sample has been given a number containing six digits (eg 16 23 05). The first 2 digits indicate the country and person supplying the timber, the second 2 digits indicate the species of timber, and the last two digits indicate the treating concentration. All samples which end with the numbers 26 to 50 are to be placed in one site in the United Kingdom, probably at the Imperial College site at Silwood. All the other samples will be returned to the persons in the following list according to the code number indicated.
Decay fungi in Finnish houses on the basis of inspection samples from 1978 to 1988
1989 - IRG/WP 1401
A summary of the causes and sources of fungal damages was made on the basis of decay samples and sample information sent to the Forest Products Laboratory of the Technical Research Centre of Finland (VTT) between 1978 and 1988. About 50-130 decay cases in wood structures were studied annually. In almost 50% of all fungusdamage cases the cause was Serpula lacrymans. The proportion of Coniophora puteana is also high and the occurrence of Antrodia and Poria species is general. The most generally damaged structures were floors. According to sample information water pipe leakages often caused the damage.
L Paajanen, H Viitanen
Soil blocks versus field test for evaluating and standardizing wood preservatives: A commercial view
1994 - IRG/WP 94-20024
On the basis of technical considerations, experience, costs and applicability, the author concludes that the soil block test and other laboratory tests have little meaning in a wood preservative standardization process and almost no merit in the commercialization of a wood preservative system. Field tests at sites known to be aggressive to preservative treated wood are strongly recommended.
W S McNamara
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
1976 - IRG/WP 145
New evidence has demonstrated that certain timber species are unexpectedly difficult to protect against biological degradation by the use of known preservation systems. Several of these timber species are expected to become of wide commercial use in the future. The issues raised are of such fundamental importance and require so intensive basic research that official bodies should be encouraged to devote funds for further study.
Collaborative soft rot tests: Results of analyses of soil samples
1976 - IRG/WP 263
C R Levy
A study of salt imbalances observed in recycled copper/chrome/arsenic preservative solutions in commercial practice
1987 - IRG/WP 3461
The study reported monitored tank solutions, sludge and other by-products using a standard CCA solution, when recycled. This recycling of the CCA solution is quite usual in between any commercial treatment schedules. Salt imbalances were observed and the possible reasons for such phenomena were studied. The paper discusses the procedure followed, the method of sampling the liquid after the charge and the analysis, to arrive finally at an aggregation and conclusion from the data.
V R Sonti, S Sonti, B Chatterjee
Natural durability of some commercial timbers of Sarawak, Malaysia in tropical marine environment
2005 - IRG/WP 05-10561
The abundant supply of timber resources in Sarawak makes timber an ideal choice to be used for marine construction. The natural durability of the main commercial timber species of Sarawak in ground contact is well established but the same is not available for marine environment. This study was conducted to assess the natural durability of 28 commercial timber species in tropical marine environment. Timber specimens measuring 30mm x 100mm x 300mm each suspended in metal cages were exposed at two sites to marine borer attack for a period of 12 years. Durability was assessed at six-monthly interval. The borer species found at the test sites were identified including one new borer species encountered. In addition, water quality parameters encompassing current speed, temperature, dissolved oxygen, salinity, turbidity and pH were monitored during the period. The results show that none of the species was durable with mean durability ranging from <0.5 – 3.0 years. Even Belian (Eusideroxylon zwageri) dubbed as the “iron wood of Borneo” and being the most durable timber species in Sarawak especially in ground contact and siliceous timber such as Kembang semangkok (Scaphium macropodum) has a mean durability of 3.0 and 1.2 years in marine environment, respectively. The majority of the species failed within six months. The specimens were destroyed by a combined action of teredine borers and pholad.
K Jenang, Wang Choon Ling
A collaborative test to determine the efficacy of poyurethane coatings on wood samples exposed in the marine environment. 1st Interim Report
1988 - IRG/WP 4145
Wood samples coated with elastomeric polyurethane (ca. 50 mils thick) were exposed for up to 2 years in 12 tropical and temperate marine test sites with known teredinid, pholad and/or crustacean infestations. All uncoated control samples were destroyed or partially destroyed. Polyurethane-coated samples were not attacked, the surfaces of the coating were sound and the polyurethane adhered well to the wood samples.
R A Eaton
The efficacy of polyurethane coatings on wood samples exposed in the marine environment. Final Report -10 Year Assessment
1996 - IRG/WP 96-10170
The results of an IRG collaborative marine trial to investigate the long-term permanence and efficacy of polyurethane coatings against marine borers are reported. PU-coated wood samples were exposed at a range of sites from tropical to cold temperate locations. The marine borer species present at the sites included teredinids, pholads, limnoriids and sphaeromatids so that each site offered its own peculiar degree of hazard. At most sites the integrity of the PU-coating was sound and wood samples were undamaged by marine borers after periods of exposure extending up to ca. 10 years. Where damage to the wood was recorded, mechanical abrasion of the coating had exposed the wood to attack by teredinids and pholads at one site and at a second site, sphaeromatids had perforated the coating. The significance of the results is discussed in terms of the protection afforded to submerged maritime timber structures coated with elastomeric polyurethane.
R A Eaton
IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water. Progress Report 7: Second report on the samples in Papua New Guinea
1980 - IRG/WP 459
This report presents the findings to date regarding specimens installed in Papua New Guinea, as part of a world-wide marine trial of certain timbers treated with CCA or CCB preservatives. The details of the trial are set out in document number IRG/WP/414. The report discusses the findings in the context of the conditions prevailing at the trial site and of the properties of the trial timbers. The trial is the third to be installed in the waters of Papua New Guinea. In 1967, pine and eucalypt samples treated either with CCA or with creosote, were installed at Rabaul, Lae and Port Moresby. Tamblyn et al (1978) describe the performance of these samples. A second trial, consisting of fifteen Papua New Guinean timbers, vacuum/pressure treated with CCA, was established at Lae and Port Moresby in 1973. This trial is described in the report of Rayner (1974). The necessity for effective treatment against marine borer attack is particularly evident in the waters of Papua New Guinea. Shillingaw and Moore (1974) found that most wharves constructed around the coast of New Guinea during the war became unserviceable within eighteen months. A timber which has a considerable reputation for durability in Australian waters - turpentine (Syncarpia glomulifera) - has proved to be vulnerable to borer attack here; it gives a service life of as little as two years at Wewak, though a somewhat longer life can be expected at Port Moresby. The most destructive borers in these waters are the members of the family Teredinidae. Nearly forty species of teredinids occur here. The isopods, Limnoria and Sphaeroma are also responsible for damage to timber wharf installations in certain areas. The pholad Martesia is also found, but never in sufficient numbers to cause economically significant damage.
S M Cragg, C R Levy
Chemical analyses of IRG/COIPM INTERNATIONAL MARINE TEST (to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water) samples
1987 - IRG/WP 4114
Chemical analysis of CCA and CCB treated timber was carried out after exposure at tropical and temperate marine sites. Results indicated that losses of all elements had occurred. In particular, losses of boron were severe. Arsenic and copper were also lost. The chromium components in both formulations was the most dominant metal remaining. The results suggest that chromium modification was important in timber treatments for the marine environment, since there appeared to be little difference in timber protection between the CCA and CCB systems.
L E Leightley
The preventive actions of three commercial wood preservatives against Dinoderus minutus
1984 - IRG/WP 1233
Dinoderus minutus is one of the most common pest insects for the bamboos. For preventing the damages of this insect, the preventive treatment of bamboos with preservatives is necessary. But because of the environmental reasons, only limited insecticides are available in Japan. The author determined the preventive effects of three commercial products against Dinoderus minutus by the medium of the Buckwheat Cake and also by a bamboo (Phyllostachys bambusolides). The results obtained were severer than ones of Lyctus brunneus. In the case of dipping treatment of the bamboo, Fenitrothion is more effective than two other preservatives (Chlordane and Phoxim).
A collaborative test to determine the efficacy of polyurethane coatings on wood samples in the marine environment. 2nd Interim Report
1990 - IRG/WP 4161
The results of a collaborative international test to evaluate the performance of elastomeric polyurethane coatings of wooden test samples exposed in seawater at 13 sites around the world are reported. The samples have been exposed at sites with known infestations by molluscan and/or crustacean wood borers. Performance data for up to 4 years exposure at some sites is presented providing information on the soundness and adherence of the coatings to wood and the degree of surface fouling. To date, all samples coated with polyurethane remain unattacked by marine borers.
R A Eaton
Commercial potential of the four-cycle method for the impregnation of green beech sleepers in Yugoslavia
1975 - IRG/WP 347
This paper was presented to the Conference on Wood Protection held in Sarajevo (Yugoslavia) in 1973. The paper was based partially on the report prepared by J. Struhar and G. F. Franciosi, who were appointed in 1972 as FAO consultants to demonstrate the new impregnation process for green beech sleepers in Yugoslavia. The so-called 4-cycle method was developed at the State Forest Research Institute in Bratislava (Czechoslovakia). The demonstration treatment was carried out at the Kolasin plant, where the double Rueping method is currently used. Comparing the double Rueping method with the 4-cycle method, the author discusses the possibility of introducing the new method into existing impregnation plants in Yugoslavia. Analysis has shown that the production costs of impregnated beech sleepers under the new method would cost 44 Dinars per m³ more for sleepers, or 530,000 Dinars annually (based on the Kolasin plant capacity). On the other hand, formation of tyloses and doat in "white" sleepers during seasoning, estimated to be 10%, would be completely avoided, saving 972,000 Dinars annually at the Kolasin plant. Besides the stock of untreated sleepers would be considerably reduced which would enable the saving of working capital at the Kolasin plant of about 2,5 mill of Dinars. It is also expected that due to higher creosote oil consumption and its even spreading through the wood, the service life of sleepers would be extended by 10 years (from 30 to 40). In such a way the Yugoslavian Railways would decrease the purchasing and installation costs by about 10 Dinars per m³ of sleepers or 1,270,000 Dinars annually (in 1972 USA$ 1 equalled 15 Dinars).
IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water. Progress Report 1: Treatment of reference samples
1977 - IRG/WP 426
It was agreed in Wildhaus on 15 May 1976 that preparations for the test detailed in Document No: IRG/WP/414 should commence immediately, but that initially only two water-borne preservatives should be used - a copper/chrome/arsenic (CCA) and a copper/chrome/boron (CCB) formulation respectively. PRL, England (R Cockcroft) would be responsible for supplying samples of the reference timbers treated with CCA and Dr Wolman GmbH, Federal Republic of Germany (W O Schulz) for supplying samples of the reference timbers treated with CCB. Untreated samples of the reference timbers would be supplied at the same time. Samples of the two wood preservatives have been kindly supplied for the test by Hickson's Timber Products Ltd, UK and Dr Wolman GmbH.
R Cockcroft, T B Dearling, W O Schulz, H V Borck
Statistical evaluation of 'micro-bending' samples for classification of wood attacking fungi
1992 - IRG/WP 92-1544
Micro-specimens from both hardwood and softwood were exposed to selected species of field isolated fungi. The strength reduction and weight loss caused by these fungi were determined. A statistical procedure was then developed to classify the fungi into brown-, white-rot, or non-decay fungal categories based on these data. The procedure reveals the extent of hazard a fungus poses to wood members. Using established base criteria as described herein, the procedure can be used to classify unknown field-isolated fungi to a pre-specified degree of certainty. Although this approach to fungal classification is not novel, it has not been used previously for decay classification. Implementation of similar classification procedures employing additional parameters would help to refine the approach allowing laboratories other than those specializing in fungal taxonomy to conduct accurate decay analyses on field samples.
B Goodell, Jing Liu, A Homola, J Jellison, J Shottafer
Trial to determine a suitable schedule for radial and longitudinal treatment of plug samples by comparison of changes in the fluid retention and the treated area
2001 - IRG/WP 01-40211
A full-cell process was carried out using different treatment schedules for radial and longitudinal samples because of the anisotrophy of flow. When timbers are impregnated with preservatives much better penetrations are obtained via the end grain than laterally (across the grain). Therefore, suitable schedules for radial and longitudinal flow directions were determined in an trial experiment using locally grown Sitka spruce, Queen Charlotte Islands (QCI) provenance, from Beddgelert Forest in North Wales. The full cell experimental schedules used were: initial vacuum 15 minutes at -0.84 bar and various pressure periods that was 5 bar pressure in radial flow direction for 15, 45, and 60 minutes, 3 bar pressure in longitudinal flow direction for 3, 6, and 9 minutes. No final vacuum was applied. After the treatment, the fluid uptake was calculated, and the fluid retention was determined on a whole-block basis. After fixation, plugs were dried and cut longitudinally through the centre and copper penetration was determined by spraying a 1% solution of Chrome Azurol-S on the cut surface and observing the blue colour indicative of copper. The preservative penetration was then measured by image analyser as depth (mm) and as total treated area (%). From the experimental data, it was concluded that the suitable schedules are 5 bar pressure for 45 minutes for the radial flow direction, and 3 bar pressure for 7 minutes for the longitudinal flow direction. Therefore these schedules are suggested to be used to examine the permeability of the different seed origins in both radial and longitudinal flow directions.
Venezuelan net of test fields for the study of the effectiveness of treatments of non commercial timbers from natural tropical forests
2005 - IRG/WP 05-20318
A net of 13 tests fields were established in Venezuela for the study of the effectiveness of the CCA and CCB treatment in secondary or non commercial woods from natural forests, two woods from fast growth plantations wee included for promote them as treated timber mainly for fence posts uses. Partial results after two years are presented and discussed the preliminary results obtained both in field and in laboratory. Those studies showed the termites and soft rot attack as major wood biodegradation agents in the country, independently of the geographical situation. The considered combinations of woods, sites and treatments, together the characteristic of each site, shown possibilities for the use of non commercial woods from results with CCA salt at higher retentions. A special call for collaboration between North - South and South - South and advice of researchers is made.
O Encinas, N Mora
Tolerance of Wood Decay Fungi to Commercial Copper Based Wood Preservatives
2002 - IRG/WP 02-30291
Due to the use of copper based preservatives like CCB or CCA for more than a century, copper tolerant fungi have appeared in some European countries in recent times. It is therefore important to find out whether this phenomenon is specific for only classical copper ingredients, or generally for all copper based formulation. Thus, we tested the tolerance of three commercial copper based preservatives and copper(II) sulphate as well as potassium dichromate for comparison. In this research, seven copper tolerant Antrodia isolates and copper intolerant fungus Gloeophyllum trabeum were tested using a screening test and standard laboratory test SIST EN 113. Screening test were performed on potato dextrose agar (PDA) with copper concentration between 5.0×10-4 and 2.5×10-2 mol/l. The tolerance determined by the screening test was not always comparable with results obtained with the standard laboratory test. However, results obtained on wood samples showed that various fungal isolates exhibited different levels of copper tolerance depending on the copper based biocide. Tolerant strains were able to decay copper sulfate as well as copper naphthenate preserved wood samples. On the other hand, even the most tolerant fungi could not decompose wood preserved with classical CCB or copper amine preservative. It can therefore be concluded that various fungal isolates exhibited different copper tolerance regarding copper formulations. This finding is very important for remediation of waste treated wood by fungi. For a successful detoxification of waste wood impregnated with multi salt preservatives like CCA or CCB the suitable tolerant fungal strains have to be used, simultaneously for synergistic action.
F Pohleven, M Humar, S A Amartey, J Benedik
Laboratory evaluation of six commercial termiticides against subterranean termite, Coptotermes gestroi Wasmann
1994 - IRG/WP 94-30034
Small specimens of Heavea brasiliensis (10 x 10 x 20 mm³) were exposed to the laboratory colony of Coptotermes gestroi Wasmann for 4 months after dip- or brush-treatment with six commercially available emulsifiable termiticides (alpha-cypermethrin, cypermethrin, permethrin, bifenthrin, chlorpyrifos and chlordane). Synthetic pyrethroids and chlorpyrifos were effective as well as 1% treatment of chlordane at lower concentrations. No marked difference in effectiveness was noticed between dip- and brush-treatments. Field trials will be planned to examine their efficacy in the actual conditions in the search for alternative termiticides.
Y Sornnuwat, C Vongkaluang, T Yoshimura, K Tsunoda, M Takahashi