Your search resulted in 31 documents. Displaying 25 entries per page.
Environmental impact of CCA poles in service
1997 - IRG/WP 97-50087
Soil samples from different depths and distances from CCA treated utility poles in Canada were analyzed for copper, chromium and arsenic content for a number of soil types, two wood species red pine (Pinus resinosa) and jack pine (P. banksiana) and different pole ages in service. A limited number of poles were equipped with water traps to collect rain water that dripped down the poles and where su...
P A Cooper, Y T Ung, J-P Aucoin
Inorganic wood preservative levels in soil near a noise barrier treated with different preservatives after 8 years in service
2005 - IRG/WP 05-50234
In March 1996 nine test sections of a noise barrier were installed near Stockholm Sweden. The test sections include untreated Scots pine, spruce and larch and Scots pine, treated with different wood preservatives. After 8 years in service, the untreated spruce, pine and larch boards in contact with the soil were significantly decayed, with an estimated service life of about 5-10 years, while the u...
P A Cooper, Y T Ung, M-L Edlund, J Jermer, O Söderström
A simple leaching procedure for in-plant monitoring of CCA fixation
1993 - IRG/WP 93-30023
A simple leaching test is described to quantitatively estimate the extent of fixation of chromated copper arsenate (CCA) preservative treated wood products. It is based on the reaction between diphenylcarbazide and unreacted hexavalent chromium leached from borings taken from treated wood during the fixation process. The test requires about 20 minutes to complete and can be set up in a treating pl...
P A Cooper, Y T Ung
A fixation model, based on the temperature dependence of CCA-C fixation
2000 - IRG/WP 00-40163
A model was prepared for the fixation of 1% CCA-C in red pine that allows the prediction of extent of fixation based on the temperature history of the treated wood following pressure treatment. The reaction kinetics of the rapid initial reaction and the slower main reaction were characterized using the Van t'Hoff equation. The initial reaction could be represented by a 10th order chemical...
P A Cooper, K M F Kazi, Jianbin Chen, Y T Ung
TBTO absorption and penetration in pine joinery treated by various processes
1989 - IRG/WP 3523
Matched sections of several White pine (Pinus strobus) and Ponderosa pine (Pinus ponderosa) mouldings were treated with TBTO by Double vacuum, modified empty-cell, 15 second dip and several preheating treatments followed by a 15 s dip treatments. As expected the double vacuum and empty-cell (batch) treatments resulted in much greater retentions and penetrations than the dip treatments. The absorpt...
P A Cooper, Y T Ung
Leaching of inorganic wood preservatives – Investigating the relationship between leachability, dissociation characteristics and long-term leaching potential
2003 - IRG/WP 03-50199
Estimation of the leaching properties of preservative components is greatly affected by the leaching test method applied since not all methods equally consider the physical components responsible for leaching. These include: wetting of the wood and penetration of water (affected by dimensions, amount of end grain, permeability, duration and nature of water exposure); solution of preservative comp...
L Waldron, Y T Ung, P A Cooper
The effect of felling time of year on CCA fixation rate and quality of selected hardwoods
1998 - IRG/WP 98-40116
White birch (Betula papyrifera), poplar (Populus sp.) and red maple (Acer rubrum) trees were harvested in winter, in spring, before the leaves flushed, after leaf flush and later in the summer. Sapwood discs were cut from the freshly felled trees, dried and cut into 25 mm and 19 mm cubes. The cubes were pressure impregnated with CCA-C and fixed under high relative humidity and at 50°C or at room ...
Y T Ung, A Taylor, P A Cooper, D P Kamdem
Effect of vegetable compost on leaching of CCA components from treated wood - An Update
1995 - IRG/WP 95-50048
In an earlier study, the effect of compost on CCA-C leaching was compared with leaching losses under different exposure conditions. Small treated cubes (25 mm³) were destructively sampled over a 12 month period and the residual CCA determined for exposure to compost in a compost bin, exposed to natural rain and buried in soil. This study provides a comparison after 3 years of samples exposed to c...
P A Cooper, Y T Ung
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
Adsorption of ACQ and CuMEA Wood Preservatives in Red pine
2005 - IRG/WP 05-30374
The rates of stabilization or fixation of ACQ subcomponents (CuO, DDAC and MEA) in red pine (Pinus resinosa) were compared for different solution concentrations (0.75%, 1.5%, 2.25% and 3% ACQ-D) and post treatment conditioning temperatures. Preservative solutions were impregnated into red pine sapwood by a full-cell treatment. Copper and MEA adsorptions from copper monoethanolamine solutions witho...
C Tascioglu, P A Cooper, Y T Ung
Effects of deck washes and brighteners on the leaching of CCA components
1999 - IRG/WP 99-50128
Small CCA treated Southern pine decks were exposed to natural weathering and the CCA leaching characteristics determined by analyzing the collected rain drippage over several rain events. The decks were then treated with a number of commercial deck washes/brighteners and the CCA components in the wash solution compared to that from water wash only. Washes containing phosphoric acid, citric acid an...
A Taylor, P A Cooper, Y T Ung
Comparison of methods for monitoring CCA fixation
1994 - IRG/WP 94-40023
The CCA fixation status in the outer 12.5 mm of pole sections of southern pine (Pinus sp.), red pine (Pinus resinosa) and lodgepole pine (Pinus contorta var. latifolia) were followed during fixation at 21°C under non-drying conditions by the following procedures: - Qualitative CrVI indication by the chromotropic acid spot test. - Quantitative CrVI in the expressate by the diphenylcarbazide method...
P A Cooper, Y T Ung, G Zanjani
Effect of humic acid on leaching of CCA from treated wood
2000 - IRG/WP 00-50151
Laboratory studies indicate that relatively high concentrations (1.000 - 10.000 ppm) of humic acids can increase the leaching of chromium and copper from CCA-C treated wood, and that copper is most affected. They also show that leaching with natural water samples can result in higher leaching of all components than leaching with distilled water. Evaluation of CCA component retentions and mass bala...
P A Cooper, D Jeremic, J L Taylor, Y T Ung
Effect of water repellents on leaching of CCA from treated fence and deck units - An update
1997 - IRG/WP 97-50086
In an earlier study, it was shown that CCA leaching losses could be reduced over an accelerated leaching and short term natural weathering exposures by post treatment application of a commercial water repellent. In this report, the effects of this coating and two commercial CCA solution water repellent additives are evaluated after two years of natural weathering. Wood boards were pressure treated...
P A Cooper, Y T Ung, R M Vicar
Susceptibility of CCA treated North American hardwoods to Chaetomium globosum decay
1998 - IRG/WP 98-10278
Seven species of hardwood, Beech (Fagus grandifolia), Basswood (Tilia americana), Maple (Acer rubrum), Oak (Quercus rubra), Trembling Aspen (Populus tremuloides), White birch (Betula papyrifera) and Yellow poplar (Liriodendron tulipifera) were vacuum or pressure impregnated with CCA, at four retention levels. The CCA was allowed to fix in the wood at 35°C. Red pine (Pinus resinosa) was also inclu...
U Srinivasan, Y T Ung, P A Cooper
Waterborne preservative treatability of tamarack (Larix laricina (Du Roi) K.Koch)
1998 - IRG/WP 98-40112
Eastern larch or tamarack (Larix laricina (Du Roi) K.Koch) lumber from New Brunswick, Canada was evaluated for preservative treatability with chromated copper arsenate (CCA-C) and ammoniacal copper arsenate (ACA). The fixation and leaching characteristics of CCA-C treated tamarack sapwood and heartwood were also evaluated. CCA-C penetration into both sapwood and heartwood was poor. ACA fully penet...
A Taylor, Y T Ung, P A Cooper
Diffusion into and bulking of the wood cell wall with polystyrene glycols (PEG)
1991 - IRG/WP 3660
The diffusion and equilibrium distribution of polyethylene glycol (PEG) in the cell walls of red pine (Pinus resinosa) and trembling aspen (Populus tremuloides) were followed by analysing the free lumen solution concentration of vacuum treated wafers at various times after treatment. PEG was more-or-less excluded from the cell walls of wood, depending on the wood species and PEG molecular weight. ...
P A Cooper, Y T Ung, D Alexander, C Holzscherer
Heat transfer and wood moisture effects in moderate temperature fixation of CCA treated wood
1994 - IRG/WP 94-40022
Practical aspects of heat transfer and fixation of wood exposed to drying conditions after CCA treatment are considered. The rates of heat transfer and CCA fixation are substantially influenced by the cooling effect of water evaporating from the wood surface when drying occurs during fixation. At least in the early stages of fixation, the wood temperature approaches the wet bulb temperature, rathe...
J Chen, M Kaldas, Y T Ung, P A Cooper
Diffusion modeling of inorganic wood preservative leaching in service
2005 - IRG/WP 05-50224-5
To evaluate the potential environmental and health implications of leaching of inorganic wood preservatives in service under different conditions, there is a need for a predictive model that provides estimates of the rate and extent of leaching over a wide range of product dimensions and exposure conditions. In this paper, we show that the leaching behavior of inorganic preservative components fr...
L Waldron, P A Cooper, Y T Ung
Moderate temperature fixation of CCA-C
1989 - IRG/WP 3522
Several Canadian treating plants are using moderate temperature (40-60C°) fixation chambers to reduce drippage and leaching from fresh CCA treated wood. In this study, chromium reduction and surface leaching properties of CCA-C treated red pine (Pinus resinosa) pole sections were monitored during exposure to temperatures of 50-60C° and 90-100% RH conditions. Chromium-VI concentration in the abso...
P A Cooper, Y T Ung
Effect of species, retention and conditioning temperature on copper stabilization and leaching for ACQ-D
2004 - IRG/WP 04-30342
The time to stabilization or equalization of the copper component of ACQ-D was highly dependent on treating solution concentration (preservative retention) and post treatment temperature. Stabilization was rapid for low preservative retentions but extended times were needed for wood treated with higher concentration solutions. The extent of stabilization was also concentration dependent with a h...
Y T Ung, P A Cooper
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
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
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
Relating CCA fixation to leaching of CCA components from treated products
1995 - IRG/WP 95-50045
The relationship between chromium fixation in CCA-C treated wood, as determined by CrVI analysis of solution expressed from treated wood and the leaching of Cu, Cr, As and CrVI in a simulated rain test are evaluated for dimension lumber (2"x6") and pole sections. Leachate concentrations after 2 hour exposure to a misting spray (about 300 mm cumulative rainfall) decrease rapidly with increased degr...
P A Cooper, R MacVicar, Y T Ung