Your search resulted in 3718 documents. Displaying 25 entries per page.
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
The extraction of boron from treated wood for quantitative analysis: A comparison of procedures
1992 - IRG/WP 92-2414
The extraction of boron preservative from treated rubberwood and scots pine samples was compared using methods based on refluxing and extraction in 1N NaOH or distilled water at 80°C. The extract solutions were analysed by Inductively Coupled Plasma spectroscopy (ICP/AES). A simple extraction procedure based on immersion of wood samples of approximate dimension 2 x 1 x 1 cm³ in distilled water a...
R J Murphy, D J Dickinson, P W McCormack, M K Lung
Effect of humidity and temperature on fastener withdrawal resistance from CCA and ACZA treated Douglas-fir
2000 - IRG/WP 00-20209
The effects of preservative treatment on fastener withdrawal was investigated in Douglas-fir lumber conditioned to two moisture regimes. In general, conditioning samples to 19% moisture content produced more substantial changes in withdrawal resistance of galvanized fasteners than did conditioning to 12%. Treatment had little or no effect on withdrawal resistance of stainless steel fasteners. With...
Sung-Mo Kang, J J Morrell
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
Kinetics and mechanism of fixation of Cu-Cr-As wood preservatives. Part 4: Conversion reactions during storage
1974 - IRG/WP 332
Precipitates simulating those produced in wood by preservative fixation reactions were prepared by the reduction of Boliden K 33 and Celcure AP solutions with hydrogen peroxide and hydrazine. The pH changes on aging at 20 and 50°C were studied and related to the chemistry of fixation previously described. Hydrolysis of copper arsenates may render arsenic acid temporarily water soluble pending pre...
S-E Dahlgren
Effect of soil chemistry and physical properties on wood preservative leaching
1998 - IRG/WP 98-50111
When treated wood is placed in contact with soil, complicated mass transfer and chemical reactions occur which causes the preservative components to leach from the wood. There are several factors that are known to affect the amount of chemical leached from wood. These are properties of the preservative and carrier, preservative retention, degree of fixation, exposure time, grain orientation, surfa...
Joan-Hao Wang, D D Nicholas, L S Sites, D E Pettry
Fixation and leaching characteristics of Douglas-fir treated with CCA-C
2004 - IRG/WP 04-50213
Fixation and leaching characteristics of CCA-treated Douglas-fir was evaluated using the expressate method and the AWPA E11-97 leaching procedure. CCA fixation, as monitored by the chromium reduction, was much faster in heartwood than in sapwood; however, copper and arsenic fixation in heartwood appeared to be incomplete regardless of the extension of fixation time. This poor fixation of copper a...
Gyu-Hyeok Kim, Yun-Sang Song, Dong-heub Lee
Influence of fungal exposure on the redistribution of copper in treated spruce wood
2002 - IRG/WP 02-10450
The redistribution of copper in treated wood after exposure to basidiomycete decay fungi is described. The micro-distribution of copper in copper(II) sulphate or copper(II) octanoate/ethanolamine treated Norway spruce wood before and after exposure to 3 different wood decay fungi was studied using transmission electron microscopy with X-ray microanalysis. The copper content of the mycelium and the...
M Humar, F Pohleven, R J Murphy, D J Dickinson, I Moris, M Zupancic, P Kalan, M Petric
Information on a project about the conditions of admissibility of wood-protecting agents in connection with environmental protection in Poland
1974 - IRG/WP 57
Wood-protecting agents are compounds acting toxically on fungi and insects. If handled improperly or carelessly, they may exert an action harmful to health and safety of men. This action is concerning: a) workers employed at the production of wood-protecting agents; b) workers employed at the impregnation, or at the transport and handling of impregnated wood; c) inhabitants of buildings with impre...
J Wazny
Alternative methodology for the environmental impact assessment of treated wood: the wood emissions ecotoxicology
2000 - IRG/WP 00-50161
Preservative products and technologies are important for optimising the use of wood and wood products in our society. The regulations of their use under the european Biocidal Products Directive 98/8/EC will require an evaluation of the environmental impact of treated wood. The methodology currently used for this determination is the PEC/PNEC ratio. It consists of calculating PEC values (Predictive...
P Marchal, H W Wegen, J Van Acker, E Melcher, R-D Peek, W J Homan, D Aston, D Rudolph, E F Baines
Residual CCA levels in CCA treated poles removed from service
2000 - IRG/WP 00-50152
Fifty-two CCA treated poles removed from service after 1 - 50 years were sampled at different depths from their below ground and above ground zones and the preservative levels and mass balances related to the location in the pole and pole age. Generally CCA retentions were still well above the toxic threshold for decay in even the oldest poles. This confirms the good leach resistance of CCA and th...
P A Cooper, D Jeremic, J L Taylor
Wood preservation in Uruguay
1987 - IRG/WP 3404
The purpose of this paper is a brief description of the current status of wood treatment in Uruguay. The forest resources of the country are summarized, the environment, their economic importance and future potential. The present wood treating facilities are described, together with the chemicals used and the standards generally accepted. Wood treated products used in the Uruguayan market are cite...
G Baillod
Leachability of active ingredients from some CCA treated and creosoted poles in service. A progress report after 10 years testing
1990 - IRG/WP 3627
CCA K33 TYPE B treated or creosoted poles, 10 pieces of each treatment type, have been monitored from the treatment plant to an electricity line, which was build up in Southern Finland in 1978. Preservative retention was determined by taking borings at four different levels: 1.5 m from the top end, 1 m above ground line, ground line and 0.5 m below ground. Determinations were made before setting u...
A J Nurmi
PXTS; A Metal Free Oligomer Wood Preserving System - A Summary of Data To Date
2004 - IRG/WP 04-30350
The world is continually looking for new wood preservative technology, especially to address environmental concerns. Recent changes in the USA have limited the use of arsenical containing formulations to industrial use through a negotiated voluntary cancellation of most residential label uses. PXTS (Polymeric Alkylphenol Polysulfide) offers a brand new technology that is an all organic system, lik...
M H Freeman, D D Nicholas, D Renz, R Buff
Toxic wood preserving chemicals in the environment: Kenya - a cause for concern
1998 - IRG/WP 98-50101-17
The uncontrolled release of wood preserving chemicals into the environment, in most African countries, is discussed. Kenya has some 25 wood preservation plants, 23 of which use formulations of Copper- Chrome-Arsenate (CCA). The bulk of treated timbers consists of poles and posts used in ground contact. Poor fixation of CCA elements are associated with the species used, Eucalyptus saligna and Acaci...
R Venkatasamy
Comparative study on the leaching of wood preservatives between natural exposure and accelerating laboratory conditions
1999 - IRG/WP 99-50134
Impregnated specimens with CCA, ACQ, and BAAC were subjected to leaching tests. Specimens of 2x2x1 cm3 in size were used for the laboratory leaching test for 10 days according to JIS K 1571. Specimens of 25x1 x1 cm3 were used for outdoor leaching test for 6 months. Total leaching amounts of boron per cm3 of specimens treated with BAAC were 325 µg in the laboratory test and 206 µg in the outdoor ...
K Yamamoto, S Motegi, A Inai
Developments in wood preservation
1976 - IRG/WP 366
The purpose of this paper is to comment very briefly upon recent developments in wood preservation so that members of the Working Group have a basic knowledge of the activities in other countries. The last paper was prepared in 1974 and this paper refers to developments since that time. The last edition of this paper was welcomed by members of IRG. Many members wrote to the author to express their...
B A Richardson
Acoustic technique for assessing decay in preservative treated wood
1998 - IRG/WP 98-20138
This study investigated the suitability of vibration techniques to assess the performance of wood preservatives in ground contact. Small stakes (10 x 5 x 100 mm3) of treated and untreated Scots pine sapwood were exposed to decay in lab-scale terrestrial ecosystems. Tests were conducted using three different soils including a garden compost soil, and soils obtained from a test field and a conifer f...
L Machek, M-L Edlund, R Sierra-Alvarez, H Millitz
Changes in transverse wood permeability during the drying of rimu and radiata pine
1990 - IRG/WP 3636
When softwoods are dried and subsequently impregnated with waterborne preservatives two problems frequently occur, preservative screening of multi-salt preservatives and difficult re-drying. To study the causes, the permeability of rimu and radiata pine wood has been measured along the three principal directions. The radial and tangential permeabilities of the green sapwood of the two species were...
R E Booker
Wood preservation sites polluted by CCA. Is potassium diphosphate incubation a catalyst for the electrodialytic remediation of these soils?
1998 - IRG/WP 98-50106
As part of an evaluation of a newly developed electrodialytic soil remediation technique, we investigated the incubation of a contaminated soil (from a Portuguese wood preservation site polluted with CCA) with potassium diphosphate as a possible catalyst for the removal of heavy metals and metalloids. A chemical sequential extraction scheme (SE) applied to the soil has shown that the potassium dip...
A B Ribeiro, G Bech-Nielsen, A Villumsen, A Réfega, J Vieira e Silva
Correlation between modulus of elasticity, mass losses and FTIR spectra of copper treated decayed wood
2006 - IRG/WP 06-10580
The composition of copper-based preservatives will change from copper-chromium to copper-ethanolamine, due to environmental demands. The most important drawback of copper-impregnated wood is the presence of tolerant fungal organisms that have developed an ability to degrade such preserved wood. In order to elucidate these processes, specimens (0.5×1.0×15 cm) made of Norway spruce (Picea abies) w...
M Humar, B Bucar, F Pohleven
Termite Response to Oil-Heat-Treated Norway spruce, Scots Pine and Eucalyptus Wood
2006 - IRG/WP 06-20325
The work here presented focused on the behaviour of subterranean termites (Reticulitermes grassei Clément) towards Oil-Heat-Treated (OHT) Norway spruce (Picea abies L.), Scots pine (Pinus sylvestris L.) and eucalyptus (Eucalyptus globulus Labill) wood, with a particular interest in the development of simple methods adequate to study the resistence of these materials to termite attack. Small test ...
L Nunes, T Nobre, C Welzbacher, A O Rapp
Testing durability of treated wood according to EN 252. Interpretation of data from Nordic test fields
2006 - IRG/WP 06-20341
To evaluate the effectiveness of new wood preservatives intended for treated wood in ground use there is a European standard, EN 252. The test shall run for five years before any formal interpretation of the results can be made.
Due to environmental concerns, the use of wood preservatives based on copper, chromium and arsenic (CCA) has been restricted in recent years. As a consequence of restrict...
M L Edlund, F G Evans, K Henriksen, T Nilsson
Performance of Preservative Treated Parallel Strand Lumber in Marine Exposures.
2006 - IRG/WP 06-30407
The performance ACZA treated Douglas-fir and CCA southern pine parallel strand lumber (PSL) was studied in marine exposures in Florida or Oregon. While materials treated to retentions below the recommended levels for marine exposure were attacked in Oregon, properly treated panels of either species performed well. Panels treated with these same chemicals and exposed in Florida experienced attack ...
J J Morrell, C S Love, P Merrick
Measuring Soil Respiration as a New Approach to Describe the Interaction Between Wood (Treated and Untreated) and Microbiologically Active Soil
2006 - IRG/WP 06-20344
Soil respirometry was employed to examine the relationship between both the performance of copper organic preservatives in contact with and the amount of carbon dioxide evolved from soil and the effect of wood treated with preservatives on carbon turnover in soil. Wood was treated with a range of copper organic preservatives intended for use in ground contact as well as an organic preservative in...
I Stephan, W Mierke