Your search resulted in 1143 documents. Displaying 25 entries per page.
Presteaming radiata pine heartwood to improve treatability
1983 - IRG/WP 3239
Steaming and holding before preservative treatment by the Bethell process greatly improved the treatment of radiata pine heartwood. Maximum penetration of preservative for the shortest holding period was obtained by the use of steam vacuum but the difference between this and steam venting was small when compared with the standard of treatment of air dried samples. A holding period of one day was s...
A J Bergervoet
Fixation and leaching of selected Malaysian tropical hardwood after treated with CCA
2001 - IRG/WP 01-40207
The objective of this study is to investigate the fixation and leaching properties of selected Malaysian tropical hardwood (sentang wood (sapwood and heartwood) and rubberwood) after being treated with copper chrome arsenate (CCA) type-C preservative. The samples were treated with retention level of 0.5%, 2.0% and 5.0%. The samples were leached and the leachate were analyzed by AAS and the amount ...
R Hashim, O Sulaiman, Tan Siew Ching, K Yamamoto
Leaching of Arsenic from Mulch Made from Recycled Construction and Demolition Wood
2005 - IRG/WP 05-50232
Mulch made from recycled construction and demolition (C&D) wood has been reported to contain chromated copper arsenate (CCA)-treated wood and potentially release arsenic in the leachate by rainfall. Such recycled wood mulch is commonly masked with iron-oxide colorant, which is known to combine with arsenic. The objective of this study was to evaluate the levels of arsenic leaching from C&...
T Shibata, H M Solo-Gabriele, T G Townsend, B Dubey
Some data on the activity of alternative fungicides for wood preservation
1985 - IRG/WP 3333
Data from laboratory tests against basidiomycete fungi are presented for 9 alternative fungicides in organic solvent formulations and also in water for one product. Results are compared with data for reference preservatives, tributyltin oxide, copper and zinc naphthenates and pentachlorophenol. Of special interest is the apparently better than additive effect of mixing tributyltin naphthenate and ...
A F Bravery, J K Carey
Influence of pre-swelling conditioning on swellometer results for CCA and water repellent additive treated wood
1997 - IRG/WP 97-20125
The pre-test moisture content and conditioning history of wafers cut from wood treated with CCA and an emulsion water repellent additive can dramatically influence swelling curves generated using a standard swellometer apparatus. The rate of water uptake and swelling increased significantly as wafers were dried to lower moisture contents prior to immersion swelling. The pre-swelling conditioning h...
A R Zahora
An inclination incising technique for the preservative treatment of refractory timbers
1991 - IRG/WP 3664
An inclination incising technique for preservative treatment of refractory timbers was examined by changing cutting angle to the longitudinal direction of test specimen and by using different types of knife edge. Incised wood were impregnated locally into incisions with CCA solution by the specified local pressure process. Width and length of penetration areas of CCA solution were measured on long...
Y Nakamura, K Nishimoto
A technique for determinging the efficacy of wood preservatives for partially treated timber
1988 - IRG/WP 2322
A technique is described for determining the efficacy of wood preservatives either for certain wood species where a full penetration cannot be achieved by normal vacuum-pressure methods or for more permeable species to look at efficacy of treated zone in preventing decay of an untreated core. Both sapwood and heartwood planks of spruce (Picea abies) and pine (Pinus sylvestris) were treated by CCA ...
A J Nurmi
CCA treatability of 100 timbers of Bangladesh
1996 - IRG/WP 96-40069
CCA treatabilities of 100 timber species grown in Bangladesh have been compared with the treatability of Pole pine (Pinus caribaea) grown in Bangladesh which revealed new five treatability grades. Sapwood of 48% species and heartwood of 9% species was found to be treatable with CCA under grade (++++) having 100% penetration. Like softwood where CCA penetrates completely in cell lumens and cell wal...
A K Lahiry
Performance of non-incised CCA-treated hem-fir decking
1993 - IRG/WP 93-40004
The question of what preservative penetration will provide an acceptable service life for treated wood in residential above-ground applications is topical in North American standards committees. Non-incised CCA-treated nominal 2 x 4 inch² hem-fir decking with penetrations close to the proposed CSA O80 2 decking standard of 80% over 5 mm, has remained without decay after 10 years exposure in south...
P I Morris, J N R Ruddick
Comparative performance of several ammoniacal copper preservative systems
1997 - IRG/WP 97-30151
The efficacy of several ammoniacal copper-based wood preservative systems was evaluated in this study. The selection of potential co-biocides was based on the results of an agar plate test. Following this, the most promising systems were evaluated in a standard field stake test. Good correlation was found between the agar plate and field stake test results. Of the preservative systems tested, copp...
D D Nicholas, T Schultz
Copper leaching from Kemwood ACQ and Embalit CBC treated wood products
2000 - IRG/WP 00-50150
TNO has performed a study on the leaching of copper from Kemwood ACQ and Embalit CBC treated wood products, further referred to as ACQ and CBC. The sawn dry wood has been impregnated using an industrial vacuum-pressure process with ACQ (with or without Ultrawood 4) or with CBC, under supervision of Flexchemie B.V. After treatment samples have been transported and subjected to leaching tests at TNO...
P Esser, W L D Suitela, H Trompetter
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
Service life of pressure treated deckings of spruce in direct contact with the ground
1988 - IRG/WP 3463
For decking outdoors in Sweden, pressure treated Scots pine (Pinus sylvestris L.) is used, on account of its treatability. The feasibility of using instead the refractory Norway spruce (Picea abies Karst.) is tested in a field trial. The spruce decks were treated together with pine decks with an ordinary Bethell process. As yet, after more than four years of exposure, neither in the battens nor in...
J B Boutelje, T Sebring
Natural exposure weathering tests: Their role in the assessment of wood preservative efficacy
1993 - IRG/WP 93-20006
Previous work has demonstrated the potential and usefulness of natural ageing procedures in e evaluation of wood preservative efficacy. This results from the combination of physico-chemical influences and microbiological interactions with both substrate and wood preservative. In this paper, results are presented for a range of biocide types. Discussions are centred on the value of natural exposure...
G R Williams, J Brown
Field tests of preservative-treated radiata pine in Japan
1995 - IRG/WP 95-30083
Test stakes of radiata pine treated with various alkyl ammonium compound (AAC) formulations and with copper-chrome-arsenate (CCA) as reference preservative were installed in 3 test sites in Japan in 1981-82. When inspected in 1995, CCA-treated stakes showed less decay at all three sites than stakes treated with other formulations. Ammoniacal copper quaternary (ACQ)- treatment was only slightly les...
M E Hedley, K Tsunoda, K Suzuki
Wood preservation in Kenya
2000 - IRG/WP 00-40190
Focussing an Wood Preservation in Kenya, the Report discusses and elaborates on Education and Training, Research, Wood deteriorating organisms, Treatment Plants and Processes, Preserving Chemicals, Specifications, Markets, Health and Safety and Environmental issues. Education and Research is limited to one Institution only, other Institutions involved with the properties and utilization of wood ha...
R Venkatasamy
Evaluating the natural durability of native and tropical wood species against Reticulitermes flavip
2004 - IRG/WP 04-10539
Environmental pressures to eliminate arsenate from wood preservatives has resulted in voluntary removal of CCA for residential applications in the United States. A new generation of copper organic preservatives has been formulated to replace CCA for decking and in-ground applications but there is no guarantee that these preservatives represent a permanent solution to all related problems. There...
R A Arango, F Green III, K Hintz, R B Miller
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
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