Your search resulted in 968 documents. Displaying 25 entries per page.
Chromated copper arsenate preservative treatment of hardwoods. Part 2: leaching performance of seven North American hardwoods
1997 - IRG/WP 97-30132
Seven North American hardwood species were treated with 2% CCA-C solution and fixed at temperatures of 21°C and 50°C and conditions of high relative humidity (95%) as described in Part 1 of this presentation. Red pine (Pinus resinosa) was included as a softwood for comparison. Adequately fixed wood blocks (99.9% chromium fixation) were exposed to leaching tests according to AWPA E11-87 test. Par...
T Stevanovic-Janezic, P A Cooper, Y T Ung
Development of a mini-block test method for the rapid evaluation of preservative performance against Basidiomycte fungi
1991 - IRG/WP 2379
Screening procedures for new biocides used as wood preservatives can be a time consuming process using conventional Basidiomycete assay procedures. This is due mainly to the long exposure periods required to achieve adequate levels of decay (weight loss) in the test blocks. A number of alternative methods have been developed but most utilise artificial substrates such as filter paper or agar in wh...
J Brown, S Caswell, G R Williams
Differences and their causes of CCA and CCB efficacay among some softwoods and hardwoods
1991 - IRG/WP 3656
Wood blocks from two softwoods and two tropical hardwoods species treated with different concentrations of CCA, CCB, and combinations of CrO3, CuS04, H3BO3 were subjected to the decay by brown rot fungus, Tyromyces palustris. CCA maintained good effect both in softwoods and hardwoods, while CCB and the other combinations lost their effectiveness after leaching. Chemicals leached from CCA treated w...
K Yamamoto, M Rokova
Comparison of Temporal Changes in Metal Leaching and Aquatic Toxicity from Wood Treated with CCA and Alternative Preservatives
2005 - IRG/WP 05-50236
This study compares the temporal variation of chemical leaching and aquatic toxicity of wood treated with chromated copper arsenate (CCA) and other copper-based wood preservatives (alkaline copper quaternary (ACQ), copper boron azole (CBA), copper citrate (CC) and copper dimethyldithiocarbamate (CDDC)). Treated wood blocks were leached for 21 days and the leachate collected was analyzed for prese...
B Dubey, T G Townsend, G Bitton, H M Solo-Gabriele
Effect of compression wood on leaching of chromium, copper, and arsenic from CCA-C treated red pine (Pinus resinosa Ait.)
2000 - IRG/WP 00-30232
In this study, the effect of compression wood formation on the release rate of chromium, copper, and arsenic elements from red pine (Pinus resinosa Ait) was investigated. Wood blocks from red pine containing compression and normal wood portions were treated with a 1.0% CCA-C solution and were then allowed to fix at 23 ± ??2°C (74 ± 4°F) for 0, 6, 24, 48, 96, 192, and 336 hours. After each fixa...
S N Kartal, S T Lebow
A diffusion and reaction model for the leaching of Cr-VI from unfixed CCA-treated wood
2001 - IRG/WP 01-50169
A physical model applicable to the leaching of any substance undergoing a first-order fixation reaction with wood is presented. Using this model and a laboratory leaching experiment with small wood samples immersed in water, the radial and tangential diffusion coefficients and the reaction rate constants of Cr-VI in unfixed CCA-treated red pine (Pinus resinosa Ait.) are measured. Reaction rate con...
L Waldron, P A Cooper
Leaching from field test stakes. Part 2: The distribution in and leaching from different parts of test stakes
1994 - IRG/WP 94-50026
Field test stakes treated with Boliden K33 (copper, chromium and arsenic) and Cuprinol Tryck (CT86) (copper and N-alkylbenzyldimethylammoniumchloride) respectively were exposed in ground contact at two different test fields in Sweden and rejected due to decay after 2 to 28 years. Stakes treated with the same preservatives were also exposed during 7 years above ground. The test stakes have been ana...
F G Evans, B Nossen, M-L Edlund
Leaching of copper-chrome-arsenic treated timber: Simulated rainfall testing
1996 - IRG/WP 96-50074
Six kiln dried radiata pine sapwood packs of timber were preservative treated with copper-chrome-arsenic preservative using a modified Bethell treatment schedule. The packs were then subjected to simulated rain leaching at specified periods after treatment. Higher chromium leachate was obtained when higher volumes of simulated rainfall were applied. Lower chromium leachate was obtained for timber ...
S Walley, P R S Cobham, P Vinden
The effect of aqueous leaching on moisture uptake by CCA-treated blocks during soil burial
1987 - IRG/WP 2283
Mass loss, moisture content and nitrogen data from two soil burial experiments with untreated and CCA-treated Scots pine (Pinus sylvestris L.), Sitka spruce (Picea sitchensis Carr) and lime (Tilia vulgaris Hayne) are presented. These show that aqueous leaching of CCA-treated wood prior to burial significantly reduces its subsequent moisture uptake from soil. In the case of lime, a reduction in the...
C A Green, G M Smith, B King
The effect of acid rain on CCA treated timber
1990 - IRG/WP 3579
The effect of acid precipitation on the leaching of copper, chromium and arsenic from timber treated with different CCA preservatives was studied in the presence of three types of soil under simulated field conditions. Pine sapwood, embedded in soil, was subjected to simulated rainfall at three different levels of acidity. The CCA preservative formulations tested were:- American Wood Preservers&am...
R J Murphy, D J Dickinson
The effect of soil pre-exposure on the results of laboratory Basidiomycete testing
1991 - IRG/WP 2385
Scots pine sapwood blocks were treated with several concentrations of copper chrome arsenic (CCA), copper chrome boron (CCB) and a copper modified quaternary ammonium compound (CMAAC). Leached and unleached samples were exposed in a basidiomycete monoculture test using Coniophora puteana, a copper tolerant brown rot. Prior to testing half of the blocks were buried in unsterile soil for 4 weeks. Th...
S M Gray
Leaching of CCA from Bombax ceiba catamarans in operation for 15 years
2002 - IRG/WP 02-50191
Core samples of wood at random were collected from all the timber pieces of each of the three catamarans made of CCA treated logs of Bombax ceiba put to continuous service for the last 15 years at the Lawson's Bay fishing village, Visakhapatnam. The samples were dried to constant weight, powdered, digested and analyzed for the residual salts of the preservative. The residual content of ...
V Kuppusamy, M Balaji, M V Rao, K S Rao
Kinetics of the dissociation of Cr, Cu, and As in fixed CCA-treated wood
2001 - IRG/WP 01-50168
The results of an experiment showing the kinetics of the dissociation of CCA compo-nents in water within treated wood samples are presented. Dry red pine (Pinus resinosa Ait.) samples were simultaneously vacuum-treated with water, then expressed to re-move the water at successive time intervals. The expressate was then analyzed for Cr, Cu, and As concentration by inductively coupled plasma (ICP). ...
L Waldron, P A Cooper
Inorganic preservative levels in soil under treated wood decks after 8 years natural exposure in Borås, Sweden
2005 - IRG/WP 05-50233
Inorganic preservative components (Cu, Cr and As) were measured to a depth of 150 mm under deck structures made with Scots pine lumber treated with several different wood preservatives and installed in Borås Sweden 8 years ago. Higher contaminant levels were observed mainly under the drip lines and in the top 50 mm of soil. Under CCA treated decks, soil arsenic concentrations increased from ba...
P A Cooper, Y T Ung, M-L Edlund, J Jermer
Differential retention and leaching of CCA (C) in sapwood and heartwood of Kenyan-grown blue gum (Eucalyptus saligna) and black wattle (Acacia mearnsii)
2005 - IRG/WP 05-30371
Retention and leaching of CCA(C) in small samples of sapwood and heartwood of Kenyan-grown blue gum (Eucalyptus saligna) and black wattle (Acacia mearnsii) were tested under laboratory conditions. Clear samples (100mm x 30mm x 40mm) were removed from the sapwood and heartwood of sampled defect-free and sound plantation trees of the two species. These were separately air-dried to 15% MC, end-seal...
R Venkatasamy
A technique for measuring preservative loss or redistribution during leaching
1983 - IRG/WP 2199
Radiata pine sapwood stakes were treated with benzalkonium chloride (AAC) or copper-chrome-arsenate (CCA). After fixation and drying the outer 2 mm and 2-4 mm layers were removed from one radial longitudinal face. The planed face was coated with a waterproof coating and AAC-treated stakes were leached for 6, 12 or 18 weeks; 12 weeks for the CCA-treated stakes. After airdrying three 2 mm layers (0-...
J A Drysdale
Impact of leachates from CCA- and copper azole-treated pine decking on soil-dwelling invertebrates
2002 - IRG/WP 02-50183
This study assessed the short-term effects on non-target soil invertebrates of leachates from a naturally durable hardwood and timber treated with two copper-based wood preservatives. Natural rainwater leachates from kwila decking, and radiata pine-decking treated with CCA or copper-azole, were collected and applied on mown lawn soil in Brisbane, Queensland. The soil study consisted of 5 treatment...
N Crumière, A House, M J Kennedy
Effect of leaching temperature and water acidity on the loss of metal elements from CCA treated timber in aquatic applications. Part 1: Laboratory scale investigation
1995 - IRG/WP 95-50046
In order to investigate the applicability of current prestandard leaching test methods, a series of experiments has been performed on CCA impregnated wood dealing with the influence of pH, temperature and agitation of the surrounding water. The leaching method used in this first part of the investigation is the European prestandard drafted by CEN/TC38/WG11, a short term dynamic leaching test under...
G M F Van Eetvelde, R J Orsler, G E Holland, M Stevens
Influence of water soluble extractives on CCA fixation and leaching performance of red maple and red oak
1997 - IRG/WP 97-30133
We have observed several peculiarities in relation to CCA fixation in red maple and red oak woods such as high variability in fixation rates and leaching performance in maple and precipitate formation in solutions expressed from CCA treated red oak wood blocks at different stages of fixation. We have postulated that the extractives could be the factor of influence, as this has already been reporte...
T Stevanovic-Janezic, P A Cooper, Y T Ung
Depletion of preservatives from treated wood: Results from laboratory, fungus cellar and field test
1993 - IRG/WP 93-50001-07
This paper compares results of preservative component losses using a range of test procedures with several different water-borne preservatives. The data shows that laboratory leaching tests are in some cases comparable to, but in other cases significantly underestimate preservative component losses when compared with field or fungus cellar depletion tests. The results also suggest that preservativ...
L Jin, A F Preston
Preservative leaching from copper-chrome-arsenic treated timber: Towards an international standard for environmental monitoring
1996 - IRG/WP 96-50076
A review of standards and legislative requirements around the world relating to environmental contamination from copper-chrome-arsenic wood preservative indicates a plethora of methodologies for expressing and determining contamination levels. The imposition of arbitrary quarantine periods for treated timber, or special fixation processes, appear to be applied without a rational analysis of what l...
S Walley, P R S Cobham, P Vinden
Speciation of leachates from CCA-treated wood
2005 - IRG/WP 05-50224-27
Different species of arsenic and chromium are characterized by different toxicities and different mobilities. The environmental impacts of CCA-treated wood would therefore be a function of the chemical forms of the metal releases. As a consequence a series of tasks were undertaken to evaluate arsenic and chromium species from CCA-treated wood. The intent of these tasks was to quantify the total...
H M Solo-Gabriele, T G Townsend, Yong Cai, B I Khan, Jin-Kun Song, J Jambeck, B Dubey, Yong-Chul Jang
The effects of pH on leaching of copper-chrome-arsenate (CCA) from pressure-treated Kenyan-grown Eucalyptus saligna and Acacia mearnsii: Initial findings.
2002 - IRG/WP 02-30298
The effects of pH on leaching of CCA from pressure-treated Kenyan-grown Eucalyptus saligna and Acacia mearnsii were tested under laboratory conditions. Small samples of the two species (100mm x 30mm x 40mm) were smooth sawn from 8-year old trees to represent equal amounts of both sapwood and heartwood, air-dried to 12% moisture content, end-sealed, and pressure-treated at a commercial treatment p...
R Venkatasamy
Long-Term Release of Arsenic, Chromium, and Copper from CCA-Treated Wood and Ash
2005 - IRG/WP 05-50227
In this study, laboratory long-term leaching studies were conducted to characterize the leaching behavior of arsenic, chromium, and copper from CCA-treated wood samples (block, chip, and sawdust) and CCA-wood ash and to determine the rate of release of the metals from the CCA wood products. The leaching solutions were periodically collected and analyzed for the concentrations of arsenic, chromium,...
Hyunmyung Yoon, Heeseok Kang, Yong-Chul Jang
Leaching tests on CCA-treated wood using inorganic salt solutions
1984 - IRG/WP 3310
Pinus radiata sapwood treated to approximately 10 kg/m³ with Tanalith NCA or Tanalith C-type CCA preservatives was ground to a fine powder and samples were then leached with solutions of calcium chloride, calcium nitrate, magnesium nitrate, or a mixture of potassium di-hydrogen orthophosphate and di-potassium hydrogen orthophosphate, at 0.03M-1.00M solution concentrations. Leached wood samples we...
D V Plackett