Your search resulted in 670 documents. Displaying 25 entries per page.
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
Performance of CCA wood preservative and CCA treated wooden materials (pole, anchor log, cross-arm etc) with special reference to Bangladesh (Series 1)
2005 - IRG/WP 05-40318
Wood is an important renewable natural resources produced by plants which is without question oldest and versatile construction material. It is composed of cellulose, hemicelluloses and lignin. Cellulose and hemicelluloses accounts for about two-thirds of the dry weight of the wood which perform the major structural role. Lignin is the remaining one-third of the wood which holds the cellulose and ...
G N M Ilias
Performance of boron and fluoride based rods as remedial treatments in Douglas-fir poles
1995 - IRG/WP 95-30070
Boron and fluoride are widely used for remedial internal treatments, but their use in North America has been limited. Recently, however, interest in these chemicals has increased as the result of concerns about the risks of fumigant usage. The performance of boron or a boron/fluoride combination was assessed in Douglas-fir poles over 1 to 3 year periods. Both chemical formulations diffused well th...
J J Morrell, P F Schneider
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
A serial exposure technique for estimating probable service life of treated timber
1978 - IRG/WP 2111
This paper briefly describes part of our preliminary work aimed at developing a test procedure that culd be adopted as a standard method. A detailed version of the work has been submitted for formal publication. In both papers, the aim is to promote interest in extended laboratory testing of wood preservatives. It is believed that this work may provide the basis of a laboratory test procedure from...
J A Butcher
Evaluating the performance of preservative/water repellent emulsion systems
1997 - IRG/WP 97-20127
Water repellent emulsions are being combined with wood preservatives to improve the weathering properties of treated wood in service. Unfortunately, few standard procedures are available to objectively compare the performance of these systems and as a result quality issues are almost completely neglected. The value of swellometer tests, water immersion tests and accelerated weathering regimes in t...
K J Archer, F Cui
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
Treatment details for the field experiment to determine the performance of preservative treated hardwoods with particlar reference to soft rot
1977 - IRG/WP 384
These notes are compiled to complement and supplement Document No: IRG/WP/367 which described the plan for the treatment of the stakes, using a CCA preservative, for the field experiment. This document gives extra details of the treatment characteristics of the different timber species and as such may give IRG members useful information on the sapwood permeability of a range of hardwoods. The repo...
F W Brooks, M R Gayles
Field testing of alkylammonium wood preservatives
1983 - IRG/WP 3248
The field test performance of five alkylammonium wood preservatives is described. The relative effectiveness of three unmodified formulations was determined by calculation of a Performance Index. Of the three, didecyldimethylammonium chloride was found to be superior to octyldecyldimethylammonium chloride, and both were more effective than alkyltrimethylammonium chloride. However, none were consid...
J N R Ruddick
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
Relative performance of copper/chrome/boron (CCB) and copper/chrome/arsenate (CCA) in ground contact
1992 - IRG/WP 92-3694
The performance of four retentions each of an oxide CCA formulation and a salt formulation of CCB in radiata pine and European beech was compared after 18 years' field exposure. In radiata pine CCA oxide was more effective (4 failures out of 40) than CCB (9 failures out of 40). However, in European beech CCB was substantially more effective (22 failures) than CCA oxide (all failed). Analy...
M E Hedley
L-joint trials: Part 2: The relationship between colonisation by decay fungi and long-term performance
2002 - IRG/WP 02-20251
Many of the L-joint trials conducted at BRE were assessed during the early stages to establish the rate of colonisation by fungi, principally basidiomycetes. At that time, a system of assessment incorporating colonisation studies was proposed for inclusion within the European Standard EN 330 but was rejected for the final version of the standard. The long-term trials associated with the colonisa...
J K Carey
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
L-joint trials: Part 3: Relative performance of a range of preservative products
2002 - IRG/WP 02-30292
Long-term trials using the L-joints described in BS EN 330 and AWPA Standard E9-97 have been in progress at BRE since 1982.
This paper records the current assessments of decay of L-joints in trials started between 1982 and 1994 with treatments applied to both Scots pine sapwood (Pinus sylvestris) and spruce (Picea sp.). Data are provided on a range of active ingredients including TnBTO, PCP, a...
J K Carey
Alternatives to CCA for ground contact protection of timber: a perspective from UK on performance and service life expectations
2002 - IRG/WP 02-30289
The proposed amendment to the European Union's Marketing and Use Directive (1976/769/EEC) in respect of arsenic in CCA wood preservatives seeks to restrict the use of CCA across the European Union. CCA is an extremely important wood preservative in the UK from the manufacturing of the product to the extent of use of CCA-treated timber. Based on our experience and judgement on the use of ...
E D Suttie, A F Bravery, T B Dearling
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