Your search resulted in 820 documents. Displaying 25 entries per page.
Progress report on co-operative research project on L-joint testing
1983 - IRG/WP 2192
A F Bravery, D J Dickinson, M Fougerousse
Wood preservatives: Field tests out of ground contact. Brief survey of principles and methodology
1976 - IRG/WP 269
This paper contains the following spots: 1.: The general need for field tests. 2.: Interests and limits of field tests in ground contact. 3.: Various methods in use for out-of-ground contact field tests. 4.: Fungal cellar tests are they an alternative to above-ground decay exposure tests? 5.: Conclusions.
How to Document the Performance of Super-Critical Treated Wood in above Ground Situations?
2005 - IRG/WP 05-20316
The paper presents practical experiences from the preparation of a new preservative treated wood product for introduction to the market. The product in question is Superwood™, which is treated with organic biocides using CO2 in a supercritical state as a solvent. The question is how to evaluate the performance of a new product such as Superwood™ in order to get an acceptance on the market and fulfil the formal requirements. In the European Union countries, the EN 599-1 is the standard that needs to be complied when approving a new product for the market, but it only focuses on the toxic limit against representative decay fungi according to EN 113. However, decay test, above ground and other forms of field tests are optional, this is not in line with the traditional test philosophy in the Scandinavian countries. The open question is to which extent treatment to the level of the toxic threshold value also ensures a long service life and expected performance of the treated commodity. Superwood™ is evaluated using a strategy, in which basic laboratory tests are done to get the toxic value (according to EN 599-1) and in addition a number of field tests are done including accelerated testing in the tropics. These tests are focussed on the evaluation of the performance criteria such as durability and service life and maintenance requirements. These questions must be answered by the producer without having a full record of performance test for their new products. A short status on the test performed on super-critical treated wood (Superwood™) is presented. Based on a comparison between field test in Scandinavia and in the tropical Malaysia a service life of more than 25 years for a specific supercritical treated product is estimated. It is stated that the existing European standardisation system is insufficient when it comes to service life prediction. A number of important questions need to be addressed by the European standardisation system as soon as possible because the market and the public opinion change quickly due to environmental concern.
N Morsing, A H H Wong, F Imsgard, O Henriksen
Field tests out of ground contact in France: Definition of the test procedure and preliminary results after 18 months
1981 - IRG/WP 2161
Wood furfurylation process and properties of furfurylated wood
2004 - IRG/WP 04-40289
The first processes for “furfurylation” of wood (wood modification with furfuryl alcohol) were developed several decades ago. Furfuryl alcohol is a renewable chemical since it is derived from furfural, which is produced from hydrolysed biomass waste. Over the last decade modernised processes for furfurylation of wood have been developed. These new processes are based on new catalytic systems and process additives. Two main processes for production of furfurylated wood have been developed for WPT (Wood Polymer Technology ASA) by the authors – Kebony 100 for high modification levels of hardwoods and VisorWood for lower modification levels of pine. Commercial production according to the Kebony process has been running since August 2000, mainly for flooring. A small Kebony production plant is now in operation in Lithuania. A larger Kebony/VisorWood production plant started up in September 2003 in Porsgrunn, Norway. Several new plants operating according to the VisorWood process, each with an annual capacity of 10 000 m³ or more, are under construction. The properties of furfurylated wood depend on the retention of grafted/polymerised furfuryl alcohol (PFA) in the wood. At high modification levels (high retention of PFA) the enhancement of a wide variety of properties are achieved: an exceptional hardness increase, exceptional resistance to microbial decay and insect attack, high resistance to chemical degradation, increase in MOR & MOE, and high dimensional stability. At lower modification levels many property enhancements also occur, however to slightly lower extent. Notable are resistance to microbial decay and insect attack, increase in MOR & MOE, and relatively high dimensional stability.
M Westin, S Lande, M Schneider
Durability of pine modified by 9 different methods
2004 - IRG/WP 04-40288
The decay resistance was studied for pine modified by nine methods of wood modification: 1) Acetylation, 2) Treatment with methylated melamine resin (MMF), 3) Acetylation followed by post-treatment with MMF-resin, 4) Thermal modification, 5) Furfurylation, 6) Maleoylation (using water solution of MG or ethanol solution of maleic anhydride), 7) Succinylation, 8) NMA-modification and 9) modification with reactive linseed oil derivative (UZA), Wood blocks of Scots pine (Pinus sylvestris L.) sapwood were modified in pilot plants. Methods 1-5 were performed by the authors at Chalmers University of Technology or at BFH in Hamburg. Methods 5-9 were part of a European research project (the Chemowood project, FAIR-CT97-3187) and therefore each of these modifications was performed by the project participant responsible for the method. For laboratory testing in TMCs (modified European standard ENV 807) and pure basidiomycete culture bioassays, smaller test specimens were cut from the modified wood blocks. Most of the modification methods were applied on test specimens for marine field testing (EN 275) and some methods to produce mini-stakes for field tests in five Swedish fields. Some modification methods result in modified wood with poor durability, whereas other methods (acetylation, furfurylation and MMF-treatment) seem to provide excellent resistance to microbial decay.
M Westin, A O Rapp, T Nilsson
In-ground performance of two formulations of chlorothalonil after five years of exposure at three test sites in Australia
1996 - IRG/WP 96-30101
Sapwood specimens of Pinus radiata D. Don and Eucalyptus regnans F. Muell. were each treated to three retentions of each of two preservative formulations (chlorothalonil in oil; chlorothalonil plus chlorpyrifos in oil) and installed in-ground at three field test sites in Australia. Specimens were treated with each formulation to achieve 3.2, 6.4 and 12.8 kg/m³ of chlorothalonil a.i. and 3.2 + 0.2, 6.4 + 0.4 and 12.8 + 0.8 kg/m³ of chlorothalonil plus chlorpyrifos a.i. For comparison, specimens of each timber species, treated to a commercial in-ground retention of a copper-chromium-arsenic (CCA) formulation, were also installed. Treated specimens (including controls) have been rated for their condition annually for attack by subterranean termites and fungal decay using a scale ranging from 4 (sound) down to 0 (failed). After five years of exposure, mean termite and decay scores for replicate test specimens at each site reveal that the performance of all three retentions of each formulation, particularly the two highest retentions, is comparable to CCA.
J W Creffield, T L Woods, N Chew
Short-term field test method with accelerated infection of Basidiomycetes in wood
1981 - IRG/WP 2155
In the ŠIPAD - IRC Wood Protection Laboratory an attempt has been made to develop a simple short-term method for field testing out-of-ground contact wood using accelerated infections with Basidiomycetes. This method makes it possible to obtain a preliminary assessment of a preservative's quality and to estimate the possibility of achieving promising results in more expensive long-term tests. The idea was to use water traps (reservoirs) and 50 x 25 x 15 mm³ laboratory infected pine blocks as the substrate to improve the possibility of inoculation of L-joints.
A new ground-contact wide-spectrum organic wood preservative: DNBP
1986 - IRG/WP 3358
A new organic wood preservative, which 25 years field tests have proved to be of efficiency and effectiveness comparable to CCA wood preservatives for ground-contact applications, is presented. Physical and chemical tests, supporting the long term field test results as well as indicating the characteristics of this preservative, are also presented.
W E Conradie, A Pizzi
An in-ground natural durability field test of Australian timbers and exotic reference species. Part 2: Progress report after approximately 13 years' exposure
1983 - IRG/WP 1189
The condition of heartwood specimens of Australian and exotic timber species after approximately 13 years' in-ground exposure is given. Four of the 5 test sites have a termite hazard in addition to the hazard from a range of decay fungi. Values for specimen life are given only where all replicates of a timber species have become unserviceable. Results give evidence leading to doubt about the accuracy of the tentative durability ratings previously ascribed to at least some of the species under test.
J D Thornton, G C Johnson, I W Saunders
A note on testing the efficacy of wood preservatives above ground
1995 - IRG/WP 95-20078
A number of test methods have been used to evaluate the performance of wood preservatives in above ground situations. These have included EN 113 tests following natural exposure weathering (NEWT), L-joint or T-joint tests, lap-joint tests, and decking tests. A new test referred to as the A-frame test has been developed and is under evaluation. This is based on a sandwich-type test in which a thin (3.5 mm) sample is exposed outdoors between two untreated samples on a rack or A-frame. The advantages and disadvantages of these types of tests are discussed in a short note.
G R Williams, J A Drysdale, R F Fox
Field testing of soil insecticides as termiticides
1986 - IRG/WP 1294
This paper reviews field methods used to evaluate soil insecticides as termiticides by the U.S. Department of Agriculture, Forest Service, Gulfport, Mississippi. Field tests are conducted on a minimum of five "nationwide sites" in the United States to determine the efficacy of chemicals in various soil types and against different termite species. Test results of selected insecticides are presented.
R H Beal
The biological natural durability of timber in ground contact
1994 - IRG/WP 94-20051
The BRE ground contact field trials for the determination of the biological natural durability of different timber species have recently been reviewed. The data obtained from these trials have been used to appraise the different ways in which natural durability may be expressed. It is concluded that the use of the mean as a method of assigning the timber to one of five durability classes may be acceptable where general recommendations are required, for instance in association with the use of wood preservatives to enhance durability, but that the median provides a better indication in this context. Where a specifier requires more detailed information on timber performance, the mean (or median) is inappropriate and a system of percentile values would be more informative.
G A Smith, R J Orsler
Thirty-four year test of on-site preservative treatments to control decay in wood above ground
1993 - IRG/WP 93-30015
This research was initiated in 1958 to investigate efficacy of various preservatives and treating methods for new lumber going into exterior structures of buildings. Post-rail units (2x4 inches) constructed of Southern Pine sapwood, Douglas-fir heartwood, and mill run western hemlock were dip- or brush-treated before or after assembly. Units were trested with pentachlorophenol in various petroleum solvents or with copper napthenate in mineral spirits. Both painted and unpainted units were exposed on a test fence in Madison, WI. Most of the painted untreated pine units (controls) failed by 34 years. Surprisingly, painting completely protected the untreated Douglas-fir units from decay and afforded substantial protection to untreated hemlock. Significant decay in painted units was present only in lightly treated pine units (2-second dip after assembly or brush treated). Copper napthenate (1% copper) was markedly less effective than the penta treatments on unpainted pine and hemlock units. There was no evidence that type of oil carrier or incorporation of a water repellent improved effectiveness of treatment. Three or 15-minute dips in penta were equally effective. Penta-grease applied to unit ends only was effective.
T L Highley, T C Scheffer
Soft rot decay of 23 CCA-treated hardwoods from Sabah, Malaysia, in ground contact in Australia
1986 - IRG/WP 1280
The performance against soft rot decay of 23 CCA-treated hardwoods from Sabah, Malaysia, was examined after 20 months in ground contact at Pennant Hills, Australia. The results indicate that between these species soft rot decay is excluded by different levels of CCA salt suggesting that the threshold level for exclusion of soft rot in these hardwoods is a function of anatomical structure/ultrastructure.
R S Johnstone
Biological effectiveness of ground-contact wood preservatives as determined by field exposure stake tests
1984 - IRG/WP 3297
Field exposure tests conducted on stakes treated with different creosotes, mixtures of creosote and waxy oil as well as different CCA wood preservatives over a period of 25 years, gave the following results: The CCA preservatives provided excellent biological protection to treated stakes, especially against fungal attack. The CCA Type I, currently approved for use under South African conditions is not inferior to the CCA Type II during long-term ground-contact exposure if the active elemental contents and effective retentions are taken into consideration. The creosotes provided good protection against termite attack but showed fairly poor fungal resistance during long-term ground-contact exposure under wet conditions. The addition of waxy oil greatly improved the effectiveness of creosotes against fungal attack. The CCA preservatives proved to be a better overall ground-contact preservative compared with the creosotes.
W E Conradie, A Pizzi
Performance of treated spruce in Canadian field test sites
1989 - IRG/WP 3506
Spruce material under test in Canadian field test sites is performing better than anticipated. From the comparison of the performance of spruce treated with various preservatives, it appears that penetration may be far more important on durability performance than the preservative itself or the retention of preservatives in the wood. However, there is still insufficient data on the influence of penetration on the performance of treated spruce. As data for species other than white spruce and data for sawn material is also incomplete, spruce cannot be accepted by the Canadian standards at this time.
J P Hösli, E E Doyle
Field trials on preserved timber out of ground contact
1978 - IRG/WP 3154
This report describes two different field trials studying the performance of preservative treatments on timber exposed to the weather, but above the ground. Results are presented on the protection afforded against decay, and on the efficiency of water-repellent preservative treatments in controlling the uptake of moisture by the timber. Proposals for a standard field test system are briefly discussed.
D F Purslow, N A Williams
Effect of felling time related to lunar calendar on the durability of wood and bamboo
-Fungal degradation during above ground exposure test for 2 years- (Preliminary report)
2005 - IRG/WP 05-20311
Current study was carried out to know whether the felling time of trees and bamboos based on lunar calendar affects natural durability of felled wood-bamboo or not. Each of one sugi (Cryptomeria japonica) tree of 28 years old and one Moso bamboo (Phyllostachys heterocycla) of around 3 years old was cut 12 times between February and December in 2003. Six sets of sugi tree and bamboo were felled in a day during “Hassen” period and the other 6 sets of them were also felled in a nearby non-“Hassen” day. There is a belief that “Hassen” should be avoided to perform destructive works such as cutting trees. “Hassen” lasting 12 days based on lunar calendar appears 6 times every year. After felling sample trees and bamboos, these specimens were subject to outdoor exposure at above ground level for 2 years. Properties of specimens such as moisture contents, mould and fungal resistance were examined periodically for 2 years. There was no clear difference in the degree of mould growth on the surface between specimens felled in a “Hassen” day and those felled in a non-“Hassen” day in the same month. The felling seasons, however, influenced the growth of mould on the surface of wood and bamboo clearly, which has been traditionally known in many cases. Fungal degradation evaluated by visual observation and the depth of pin penetration using Pilodyn during 2 years exposure was not affected by not only “Hassen” or non-“Hassen” also seasons when tree and bamboo felled.
K Yamamoto, S Uesugi, K Kawakami
Natural durability of wood in ground contact - A correlation between field and laboratory tests
1985 - IRG/WP 2182
A field test is being carried out to evaluate the natural durability of 20 hardwoods. The resistance to decay and termite attack was evaluated in accelerated laboratory tests. The results of the field test after 6 years and 8 months indicate that there is not necessarily agreement between results from laboratory and field tests. It is pointed out that apart from the artificiality of the laboratory tests, a possible cause of the discrepancies can be the different performance of the same wood species in different test sites.
M S Cavalcante, G A C Lopez, R G Montagna, M E S Fosco Mucci
In-ground evaluation of a copper azole wood preservative (Tanalithâ E) at a tropical Australian test site
1996 - IRG/WP 96-30100
A field trial to determine the in-ground termite and decay resistance of Pinus radiata D. Don impregnated with a copper azole formulation, TANALITHâ E, has been established at a tropical site in the Northern Territory of Australia. Four retentions of TANALITHâ E, containing 1.54, 2.08, 2.92 and 4.30 kg/m³ of Cu, are being evaluated. For comparison, Pinus radiata specimens treated to two retentions (0.56 and 1.18 kg/m³ of Cu) of the benchmark CCA preservative TANALITHâ C, have also been included in the test. Treated specimens (including controls) have been assessed for degrade by subterranean termites and fungal decay, after 4, 7, 16 and 27 months of exposure, using a scale ranging from 4 (sound) down to 0 (failed). Over the duration of the trial, specimens have been contacted by the economically important species of termites Mastotermes darwiniensis Froggatt, Coptotermes acinaciformis (Froggatt), Schedorhinotermes spp. and Heterotermes spp. After 27 months of exposure, the mean termite and decay scores for replicate test specimens indicate that the performance of TANALITH â E is comparable to CCA.
J W Creffield, J A Drysdale, N Chew
Ten year field test with a copper-borate ground line treatment for poles
1993 - IRG/WP 93-30017
A wood preservative paste consisting of borax and copper naphthenate has been tested to determine its efficiency in protecting wood from decay fungi and insects. The paste was applied to polyethylene-backed wraps that were fastened to the below-ground portions of unseasoned southern pine pole stubs. After 4 years of exposure in Mississippi, the untreated control stubs were completely deteriorated. The below-grade portions of the treated stubs remained sound after nearly 6 years of exposure due to movement of copper and diffusion of the borate throughout the cross section. Borate and copper also moved vertically in the stubs and was present in sufficient amounts to protect sections of the stubs as high as 3 feet above grade. After 9 years of exposure, the below-grade portions of the treated stubs had limited areas of decay and no termite damage; the majority of the cross section remained sound. Wood analysis indicated that concentrations of borate in the sound areas were about 1/10 the estimated toxic threshold. A visual examination and push test indicated that the treated stubs continued to be protected at groundline after 10 years of exposure. It is hypothesized that the continued protection of the below-grade portions of the stubs against both decay fungi and subterranean termites is the result of copper-borate complexes that have formed in the wood.
T L Amburgey, M H Freeman
Natural durability of European wood species for exterior use above ground
2003 - IRG/WP 03-10499
The main interest in using more timber for exterior constructions is to protect the environment, where wood is considered an environmentally friendly material. However, chemicals for wood protection are getting more and more restricted, consequently, the focus on the natural durability of wood is increased. Good, well-documented data on the durability of wood species in ground contact exist, which form the basis of the standard EN 350-2:1995. Yet, we have, however, no useful documentation for the natural durability of wood, when used outdoors above ground. The study is large-scale field trials, including more than 30 species, where the objective is to define and document the natural durability of European wood species when used outdoors above ground. The idea of the test set-up is to simulate different application situations of wood to recommend individual wood species for specific purposes – fit to purpose. Two basically different test set-ups are used: 1. Panels in close-to-practice applications: Horizontally oriented with and without covering. Vertically north turning and vertically south turning oriented with and without covering as well as 45 degrees south turning oriented without covering. 2. Lap-joints in standardised field exposures: The set-up is according to the CEN-standard ENV 12037: Wood Preservative – Field Test Method for determining the relative protective effectiveness of a wood preservative exposed out of ground contact – Horizontal lap-joint method. The paper presents the results of the appearance, the moisture fluctuation, mould growth and wood decay after 3 years field trial.
B Lindegaard, N Morsing
Calculation of preformance index of Bardac 20 (an alkylammonium compound) evaluated in a field stake test
1982 - IRG/WP 3206
Bardac 20 treated stakes have been in test for three years at the Westham Island test site near Vancouver, B.C. The Performance Index for the preservative was calculated and found to be 0.009 which infers that, at the standard retention, Bardac 20 added 0.9 y to the life of the stake. It may be concluded that when tested using a standard field stake test using ponderosa pine (Pinus ponderosa Laws) sapwood at a standard retention of 6.35 kg/m³ Bardac 20 did not fulfil the expectations indicated from the laboratory screening test conducted earlier. Studies are in progress to determine the cause of this discrepancy in performance with a view to improving this class of compound as a wood preservative for use in ground contact situations.
J N R Ruddick
An in-ground natural durability field test of Australian timbers and exotic reference species. Part 5: Extensive data from a site where both decay and termites are active. Results from a full-replicated set of heartwood specimens from each of ten myrtaceous hardwoods after 18, 19 and 20 years' exposure - A discussion paper
1988 - IRG/WP 2324
Extensive data are presented on the decay situation, the termite situation and the decay-termite associations; all gathered from a fully-replicated set of heartwood specimens of 10 hardwood timbers after 18, 19 and 20 years' exposure in the ground at a single test site, i.e. a semi-arid steppe site. Sixteen tables are presented in addition to the one table providing the rating data; the latter representation of specimen condition being essentially all the data normally being recorded from field tests, whether these be of natural durability or preservative treated specimens. The authors give this "extra" data to show the type of information obtainable as a result of applying both mycological and entomological expertise to field assessments. Instead of discussing these results. the authors wish to generate some discussion by asking questions such as - is some of all of this information of value? - What additional/alternative information would interested scientists wish to see with respect to the most durable timbers in a test such as that examined in this report?
J D Thornton, G C Johnson, J W Creffield