Your search resulted in 806 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
A suggestion for the improvement of the chemical protection of wooden poles
1987 - IRG/WP 3445
Insufficient drying of white poles in Sweden causes inadequate penetration of the impregnation compounds, CCA salts and creosote, in a varying proportion of the treated poles, and with pretreatment decay present, sooner or later, internal fungal attack in the ground-line zone of the standing poles is the result. The application of a diffusing fungicide in the ground-line zone in connection with th...
H Friis-Hansen
The multi-phase pressure (MPP) process. One stage CCA treatment and accelerated fixation process
- Concepts proved by repetitive pilot plant treatments
1997 - IRG/WP 97-40079
Twenty-four charges of radiate pine roundwood or sawn timber were treated using the MPP Process and hot CCA solution. Treated timber met the CCA retention and penetration requirements of the NZ Timber Preservation Council for Hazard Classes H3 to H5. The objectives of the trials were: (1) To "stress" CCA solution by repetitive heating, treating and cooling to determine its stability in the process...
A J Pendlebury, J A Drysdale, K Nasheri, H Pearson, M E Hedley
A study on the pressure impregnation of Eucalyptus globulus fence posts with CCA preservatives. Part 1
1988 - IRG/WP 3470
This paper describes the impregnation with CCA preservatives by full-cell process of Eucalyptus globulus fence-posts. Several treatments were made for different times of initial vacuum and treating pressure, with fence-posts from two coppice plantations (1st and 2nd rotations), assembled into three diameter classes: small, medium, large. The results concerning the absorption and lateral penetratio...
D De Sousa Castro Reimão, L Nunes
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
Effects of surfactants and ultrasonic energy on the treatment of wood with chromated copper arsenate
1977 - IRG/WP 3108
Sugar pine stakes 1'' x 1" x 16" were treated by a hot-water bath followed by soaking in cold CCA solution for 10 to 30 minutes. A similar number of stakes were treated by a cold-cold bath. Half of the stakes were subjected to ultrasonic energy during the CCA bath. The mean absorption for stakes given the hot-cold bath was 18.52 pcf (297 kg/m³) and 4.64 pcf (74 kg/m³) for those...
C S Walters
Soft rot test of copper/chrome/arsenic treated heartwood of three Malaysian timbers
1991 - IRG/WP 2381
Standardized heartwood blocks of kempas (Koompassia malaccensis), keruing (Dipterocarpus sp.) and tualang (Koompassia excelsa) were impregnated with 0 to 6.3% (w/v) CCA and challenged to decay by a mixed inocula of Chaetomium globosum, Glenospora graphii, Humicola grisea, Petriella setifera and Trichurus spiralis in a containerized vermiculite-burial decay system according to draft CEN/TC 38 WG 4....
A H H Wong, R-D Peek
A study of the decay type potential of seven soils
1992 - IRG/WP 92-1539
The aim of this experiment was to determine the significance of the fungal inoculum potential and physico-chemical properties of five field trial test site soils, a garden compost known to cause white rot in copper treated fence palings, and soil from a zone between 2 and 15 centimetres from a CCA treated post with brown rot, in causing differential decay type in Pinus radiata and Poplus deltoides...
R N Wakeling
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
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
The implementation of restrictions on the use of arsenic and chromium based wood preservatives in Sweden
1995 - IRG/WP 95-50062
In 1992 the Swedish National Chemicals Inspectorate introduced restrictions on the use of wood treated with arsenic and/or chromium based wood preservatives. Such wood is now in principle only allowed for use in ground contact or in water. These restrictions have had considerable influence on the use of wood preservatives for sawn timber for the Swedish domestic market. Thus only 35% of the preser...
J Jermer, M-L Edlund, K Nilsson
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
Observations on the effect of two preservatives on settlement and development of the marine wood-borer Martesia striata L
1983 - IRG/WP 498
Small heartwood specimens of three tropical hardwoods namely kusia or opepe (Nauclea diderrichii (De Wild) Merrill), emire or idigbo (Terminalia ivorensis A. Chev.) and subaha or abura (Mitragyna stipulose (D.C.) O. Kuntze) were treated with either creosote (BSS 144 type) or a copper-chrome-arsenic preservative and submerged in the sea at Tema, Ghana. They were regularly cleaned of fouling and obs...
J E Barnacle, F F K Ampong
A prototypical needle-incisor for refractory timber
1995 - IRG/WP 95-40041
A needle-incisor was manufactured for trial. This machine has an incising mechanism that a set of needles held by a rotary plate incises timber which is moved toward the front simultaneously, and then another set of needles incises a new part of the timber. Timber is incised by recycling the process. Timber incised of 4400 incisons/m² with the depth of 56 mm by 2.8 mm-diameter needles on all the ...
A Yakuwa, H Endoh, M Mori, S Doi
Electrodialytic remediation of CCA-treated wood in larger scale
2005 - IRG/WP 05-50224-20
A pilot plant for the electrodialytic remediation of CCA-treated waste wood has been developed and tested at the Technical University of Denmark. Results from two experiments with different amount of wood chips are presented here. Prior to the electrodialytic remediation the wood was soaked in oxalic acid and phosphoric acid. The main purpose of soaking is to remove the most available fraction fir...
I V Christensen, L M Ottosen, A J Pedersen
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
Butt-end incising to improve penetration and retention of CCA in Eucalyptus saligna telegraph poles in Kenya: Preliminary results
2002 - IRG/WP 02-40243
Incising to improve penetration and retention of Copper Chrome Arsenate (CCA) in the butt end of Eucalyptus saligna telegraph poles was investigated. Debarked, seasoned (15% MC) butt-end samples from full size telegraph poles were incised using four patterns of incisions, sealed at
the top or small diameter end, and pressure treated, together with un-incised samples, with CCA-C (3.0% oxide typ...
R Venkatasamy
Glulaminated poles - Progress report after 7 years' testing
1987 - IRG/WP 3444
In 1979 a number of glulaminated poles with various preservative treatments were placed in a greenhouse at Uppsala, at the Simlångsdalen test field in southern Sweden and under a power line just south of the Arctic circle in order to study their resistance against biological degradation. The tests have shown that the comparatively best performance will be obtained if each lamination is treated wi...
J Jermer, Ö Bergman
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
IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water. Progress Report 1: Treatment of reference samples
1977 - IRG/WP 426
It was agreed in Wildhaus on 15 May 1976 that preparations for the test detailed in Document No: IRG/WP/414 should commence immediately, but that initially only two water-borne preservatives should be used - a copper/chrome/arsenic (CCA) and a copper/chrome/boron (CCB) formulation respectively. PRL, England (R Cockcroft) would be responsible for supplying samples of the reference timbers treated w...
R Cockcroft, T B Dearling, W O Schulz, H V Borck
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
Will political initiatives stop the use of preservative-treated wood in Sweden?
1990 - IRG/WP 3578
The Swedish government has initiated several investigations on how to reduce the use of different chemicals. Among these chemicals are creosote, arsenic, chromium and organotin. A special investigation was carried out concerning wood preservatives resulting in different proposals on how to reduce the use of preservatives and preservative treated wood. The most important proposals were an "environm...
J Jermer, M-L Edlund
Studies on the mobility of arsenic, copper and chromium in CCA-contaminated soil
1990 - IRG/WP 3571
CCA contaminated soils from six Swedish preservation plants were investigated primarily to study the mobility of arsenic but also that of copper and chromium in the soils. The soil samples represented average types with different amounts of clay, organic matter, arsenic, copper, chromium and different pH. The total soluble amounts of the elements were measured. The pH dependent solubility and the ...
J Bergholm
The environment and the timber preservation in the Benelux countries
1990 - IRG/WP 3580
The environment has become a major issue in all industries. To focus on the timber preservation industry an analysis is made of the production chain. Suggestions are made for diminishing or excluding emissions of agents of pollution. After a review of the legislation in Holland, some important statements are made on the production process, the products involved and the waste materials. Finally raw...
C De Mey, R Leegwater
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