Your search resulted in 452 documents. Displaying 25 entries per page.
Copper leaching from Kemwood ACQ and Embalit CBC treated wood products
2000 - IRG/WP 00-50150
TNO has performed a study on the leaching of copper from Kemwood ACQ and Embalit CBC treated wood products, further referred to as ACQ and CBC. The sawn dry wood has been impregnated using an industrial vacuum-pressure process with ACQ (with or without Ultrawood 4) or with CBC, under supervision of Flexchemie B.V. After treatment samples have been transported and subjected to leaching tests at TNO...
P Esser, W L D Suitela, H Trompetter
Effectiveness of CCA fixation to avoid hexavalent chromium leaching
2002 - IRG/WP 02-50187
It is generally assumed that hexavalent chromium in chromated copper arsenate wood preservative is substantially reduced to trivalent chromium during fixation and that the potential to leach the more toxic CrVI is minimal. However, there are occasional claims some hexavalent chromium remains in wood after fixation and that small amounts of CrVI are available for leaching. One problem is that ot...
P A Cooper, D Jeremic, Y T Ung
Natural exposure weathering tests: Their role in the assessment of wood preservative efficacy
1993 - IRG/WP 93-20006
Previous work has demonstrated the potential and usefulness of natural ageing procedures in e evaluation of wood preservative efficacy. This results from the combination of physico-chemical influences and microbiological interactions with both substrate and wood preservative. In this paper, results are presented for a range of biocide types. Discussions are centred on the value of natural exposure...
G R Williams, J Brown
Efficacy of deltamethrin associated with TCMTB and MBT for the temporary protection of timbers immediately following their sawing, in tropical countries
1987 - IRG/WP 1321
K-Othrine bois 2.5 "sciage"Ò containing 2.5 g/l of deltamethrin, 50 g/l of TCMTB and 50 g/l of MBT used at a 6% dilution controls effectively during the drying process of the freshly sawn wood, the insects attacking wet wood, the staining fungi and the rots. The protection lasts 4 months. The efficacy trials carried in 1985 and 1986 in the CTFT ("Centre Technique Forestier Tropical") of Abidjan, ...
J S Duguet, V Dartigues
The possible role of mobile CCA components in preventing spore germination in checked surfaces, in treated wood exposed above ground
2001 - IRG/WP 01-30263
Untreated check surfaces are often exposed in CCA-treated lumber of refractory species used above ground since, during weathering, some checks develop beyond the preservative penetrated zone. However, decay is seldom observed in these checks even after many years of exposure. It is hypothesized that minor amounts of mobile CCA preservative components redistribute during weathering into checks, and...
S Choi, J N R Ruddick, P I Morris
Evaluating possibilities of leaching of deltamethrin and TCMTB (insecticides and fungicide for protecting wood) by rain water or by soaking in water
1988 - IRG/WP 3464
Deltamethrin and TCMTB have been subjected to several field leaching tests on freshly fallen trees and in the laboratory, using standard EN 84. All the trials gave the same results and confirm that Deltamethrin and TCMTB are not washed out after they have been allowed to penetrate the trunk surface properly. According to the EN 84 standard, less than 1% Deltamethrin and less than 1.7% TCMTB were r...
J S Duguet, V Dartigues
Improvement of wood decay resistance by tannin impregnation
1991 - IRG/WP 2380
The fungical effect of tannins is appraised after exposure of treated woods samples to wood rotting fungi. A screening-test is carried out with several solutions containing extracts of two kinds of tannins; a condensed tannin derived from Quebracho heartwood (Schinopsis sp.) and a hydrolyzable one extracted from chestnut heartwood (Castanea sativa Mill). If a fungicidal action was indeed found it ...
D Dirol, A Scalbert
The influence of soil pH on leaching of CCA elements from pressure-treated Eucalyptus saligna sapwood: environmental implication
2003 - IRG/WP 03-50203
Evidence is accumulating as to poor distribution and fixation of CCA in tropical hardwoods, and there is therefore a necessity to investigate the permanency of CCA in tropical hardwoods. The relationship between soil pH and leaching of Cu, Cr and As from CCA pressure-treated sapwood of Kenyan-grown Eucalyptus saligna was tested under laboratory conditions. Small sapwood samples were pressure-tre...
R Venkatasamy, D N Okwara
Accelerated decay tests to investigate postulated effects of tannins on CCA efficacy in wood
1988 - IRG/WP 3497
Five groups of blocks (10 x 10 x 5 mm³) viz., Pinus patula, Pinus patula impregnated to 4% (w/w) tannin; Eucalyptus grandis, Eucalyptus grandis with natural tannins extracted; and extracted Eucalyptus grandis with tannins returned as above; were prepared. Blocks from each group were then treated to 0, 5, 10 and 15 kg/m³ CCA and challenged in four 15-week decay tests, viz., soil burial, and expos...
U L Scherer, A A W Baecker
Fungicidal efficacy of some dimethyldithiocarbamates, dymethylaminopropionitrile and some salts of S-substituted thioglycolic acid
1998 - IRG/WP 98-30180
Screening for fungicidal activity against Trametes versicolor and Coniophora puteana of the following compounds was performed: sodium N,N-dimethyldithiocarbamate, dimethylalkylammonium (C12-C14) N,N-dimethyldithiocarbamate, benzyldimethylalkylammonium (C12-C14) N,N-dimethyldithiocarbamate, N,N-dimethylaminopropionitrile and ammonium, copper and zinc salts of N,N-dimethyldithiocarbamoylacetic acid....
M Petric, F Pohleven, M Humar, U Kolman
Délavabilité de bois ronds traités avec un sel CCA dans des conditions réelles de stockage. Incidence pratique de la fixation accélérée par étuvage. Impact effectif sur l'environnement
1993 - IRG/WP 93-50001-23
Un essai de terrain a été organisé pour mesurer concrètement, dans des conditions aussi proches que possibles des conditions réelles de terrain, les pertes effectives en produit de traitement lorsque le bois traité est soumis à des intempéries. L'essai a été conduit sur des bois ronds (poteaux), traités en autoclave par procédé Bethell avec un sel CCA de type C, avec comme fi...
M Rayzal, F Larroze
Comparative study on leaching of CCA from treated timber: Modelling of emission data
1994 - IRG/WP 94-50027
Results of a comparative study on leaching of CCA from treated timber are reported. The study aims at investigating the applicability of prestandard leaching test methods for modelling purposes. Prestandards used are the European standard proposed by CEN/TC38/WG11 and NEN 7345 (Dutch prestandard for building materials). Parameters of study are type of fixation, wood species (pine - spruce), specim...
G M F Van Eetvelde, M Stevens, L Van der Mijnsbrugge
The effect of water-repellent additives on the leaching of CCA from simulated southern Yellow pine decks
2000 - IRG/WP 00-50158
End-matched SYP boards were pressure-treated with CCA or CCA in combination with commercial water repellent additives. After fixation and drying, the boards were placed in plastic boxes and exposed outside in Harrisburg, NC. Plastic supports were used to keep the boards above the water collected. Over a period of five months, rain run-off water from 14 natural rainfalls were collected and analyzed...
F Cui, P J Walcheski
Long-term efficacy of wood dip-treated with multicomponent biocides
2005 - IRG/WP 05-30379
Biocides designed for prevention of indoor mold growth on wood-based materials need to provide long-term protection under conditions of high humidity. Specimens of kiln-dried southern pine and unseasoned southern pine, aspen, and Douglas-fir were dip-treated with borate-dimethylcocoamine (DMCA) supplemented with voriconazole, thiabendazole, or thujaplicin and evaluated at 4-week intervals for inhi...
C A Clausen, V W Yang
Effects of fixation conditions and seawater on leaching of wood treated with marine retention CCA
1997 - IRG/WP 97-50088
The effect of post-treatment conditioning temperature and humidity on leaching of chromated copper arsenate (CCA) was compared in seawater and deionized water. Southern pine cubes treated to 40 kg/m3 CCA were stored at 2° C and 82% relative humidity (RH), 24° C and 65% RH, or 32° C and 30% RH for 3, 10, or 17 days. Cubes were then leached in deionized water or artificial seawater. The rate of l...
S T Lebow
Fixation of copper-chrome-arsenic treated timber: A comparison of leaching methodologies
1996 - IRG/WP 96-50075
Five packs of kiln dried radiata pine heartwood were treated with copper-chrome-arsenic preservative treated, utilising a modified Bethell treatment schedule. Two methods of determining the level of preservative fixation were compared. These included the diphenylcarbazide method and simulated rainfall testing. The fixation levels were generally higher for tests involving simulated rain leaching. F...
S Walley, P R S Cobham, P Vinden
Leaching characteristics, decay and termite resistance of treated wood with boron compounds, N'-N-(1,8-Naphthalyl) hydroxylamine (NHA-Na), and hydroxynaphthalimide (NHA-H)
2003 - IRG/WP 03-30307
Despite many advantages of boron wood preservatives, boron itself does not adequately protect wood in ground contact and exterior applications because its natural diffusibility and susceptibility to leaching. As a result of previous studies to limit or decrease boron leaching, several fixation systems have been developed. In this study, we evaluated the effects of N'-N-(1, 8-Naphthalyl) h...
S N Kartal, Y Imamura
An appraisal of methods for environmental testing of leachates from salt-treated wood; part 1
1998 - IRG/WP 98-50115
The magnitude and diversity of leaching tests with salt-treated wood, performed by institutes as well as industry, strongly appeal for harmonisation towards one single method. That procedure should be well-defined, cost- and time-effective and moreover be extended with a clear detection and interpretation scheme.
The paper(s) presented here tend to evaluate 2 existing leaching methods, the ENV 12...
G M F Van Eetvelde, M Stevens, F Mahieu, H-W Wegen, A Platen
Observations on the performance of copper-based wood preservatives in fungal cellar (soil-bed) tests
1994 - IRG/WP 94-20047
Fungal cellar (soil-bed) tests are considered to be an important tool for the evaluation of the performance of ground contact wood preservatives. Facilities of this type have been established world wide although caution has been exercised in their introduction into standard testing methods for the approval of wood preservatives. This is the result of concerns over the variability in the biological...
G R Williams, D Rudolph, M E Hedley, J A Drysdale, R F Fox
A comparison of the leaching resistance of diammine-copper complexes and copper carbonate precipitated in wood
1997 - IRG/WP 97-30158
Previous studies have shown that during treatment of wood with ammoniacal copper solutions, both simple copper precipitates and diammine-copper complexes are formed. The objective of the present study is to determine the relative importance of both forms of copper, on such aspects as preservative leachability and biological performance. In the current experiment, the leachability of copper carbona...
Xiao Jiang, J N R Ruddick
On-site test for indicative determination of leaching of components of preservatives from treated timber
1993 - IRG/WP 93-50001-12
In the late eighties the environmental concern about treated timber increased and it is still a hot issue in the Netherlands. From the environmental point of view three phases in the timbers life cycle can be distinguished: - the production phase - the service life - the waste phase. In the Netherlands at this moment much emphasis is laid on the production phase. In 1992 this has led to a new legi...
W J Homan, H Militz
Effect of treating process on efficacy of CCA in a laboratory decay test
1990 - IRG/WP 3628
Test samples of Pinus radiata sapwood measuring 40x40x500 mm³ were treated with a range of concentrations of the copper-chrome-arsenate (CCA) formulation "Tanalith C" using Rueping (empty cell), Lowry (empty cell) and Bethell (full cell) treatment processes. Samples were then reduced to 40x40x7 mm³ test blocks and exposed to the decay fungus Coniophora puteana using an agar/block technique. Repl...
M E Hedley, K Nasheri, J G Van der Waals
A technique for assessing the preventive efficacy against decay fungi of preservative treatments applied to wood
1988 - IRG/WP 2309
A method is described in which test blocks with envelope preservative treatments can be challenged by selected test fungi previously established on an untreated feeder block. The progress of the test fungus through the treated zone is monitored using novel baits or sensors inserted in holes drilled into blocks to within predetermined distances of the face being challenged. Preliminary results show...
J K Carey, A F Bravery
The antifungal efficacy of Guayule resin
1987 - IRG/WP 3429
The Naval Research Laboratory is evaluating the non-rubber-producing portion of guayule (Parthenium argentatum) resin as a protectant for wood in terrestrial and marine service. This study phase, in collaboration with the universities of Arizona and Mississippi State, evaluates the resin's fungicidal worth. Resin-impregnated pine sapwood was exposed to brown rot fungi (Gloeophyllum trabeu...
J D Bultman, R L Gilbertson, T L Amburgey, J E Adaskaveg, S V Parikh, C A Bailey
Copper naphthenate-treated Southern Pine pole stubs in field exposure: - Part 1: Gradient & biodeterioration analysis 12 years after treatment
2000 - IRG/WP 00-30242
Naphthenates have been used for the preservation of timber and cellulose since their original identification in Russia in the early 1880's as part of a series of petroleum characterizations. Later work in the development of copper naphthenate as a heavy-duty preservative for poles led to the development of various treating cycles similar to other oil-borne systems. Recent work concerning ...
H M Barnes, M H Freeman