Your search resulted in 638 documents. Displaying 25 entries per page.
Depletion of preservatives from treated wood: Results from laboratory, fungus cellar and field test
1993 - IRG/WP 93-50001-07
This paper compares results of preservative component losses using a range of test procedures with several different water-borne preservatives. The data shows that laboratory leaching tests are in some cases comparable to, but in other cases significantly underestimate preservative component losses when compared with field or fungus cellar depletion tests. The results also suggest that preservativ...
L Jin, A F Preston
Leaching of Copper from ACQ treated wood exposed above ground
2004 - IRG/WP 04-50219
The leaching of chemicals of ACQ Type C treated wood exposed above ground for 16 months was studied. Commercially treated Hem-fir boards (Tsuga heterophylla Raf. and Amabilis fir Forb) of 37.5 mm by 87.5 mm were used. The amounts of chemical leached monthly by the rainfall were determined and the leachate was collected and analyzed. Also, the environmental factors influencing the leaching were ...
P A Chung, J N R Ruddick
Preservative leaching from copper-chrome-arsenic treated timber: Towards an international standard for environmental monitoring
1996 - IRG/WP 96-50076
A review of standards and legislative requirements around the world relating to environmental contamination from copper-chrome-arsenic wood preservative indicates a plethora of methodologies for expressing and determining contamination levels. The imposition of arbitrary quarantine periods for treated timber, or special fixation processes, appear to be applied without a rational analysis of what l...
S Walley, P R S Cobham, P Vinden
Resistance of twenty-five species of timbers to marine borer attack at Visakhapatnam, east coast of India
1994 - IRG/WP 94-30036
Observations on the natural resistance of 25 species of timbers to marine borer attack for a twelve month period at the fishing harbour, Visakhapatnam, East Coast of India, indicate that none of the species was free from borer attack. The damage was mainly by teredinids - Teredo furcifera and Lyrodus pedicellatus. Martesia striata, Teredo parski, Bankia campanellata and Lyrodus bipartitus were als...
K S Rao, M Balaji, V V Srinivasan
Preliminary Studies on ZiBOC- A Potential Eco-friendly Wood Preservative
2005 - IRG/WP 05-30372
Over the past decade, the wood processing industry has been increasingly involved in strategies to minimize the environmental impacts of treated wood. One sign of this is the dramatic increase in the use of preservatives based on inorganic metal oxides, which fix in wood. Among such preservatives the most common is chromated-copper-arsenate. In Ascu chromium and arsenic both are carcinogenic thus...
S Tripathi, J K Bagga, V K Jain
The present status of wooden catamarans of the Indian Coast
1997 - IRG/WP 97-10231
Catamarans (a.k.a. kattumarams) are the most widely used fishing craft in India, and hundreds of thousands of poor, traditional fishermen depend on these vessels for their livelihood that are almost made entirely of wood. In recent years, acute shortages and phenomenal increases in prices of timber species used in catamaran fabrication have been reported, causing great hardship to the user communi...
K S Rao
Leaching Characteristics of Alder Wood Treated with Copper Based Wood Preservatives
2005 - IRG/WP 05-50225
In this study, it was designed for determining leaching characteristics of CCA and alternatives wood preservatives. Alder wood blocks were treated with CCA (1 % and 2 %), ACQ-1900 (2 % and 3 %), ACQ-2200 (1 % and 2 %), Tanalith E 3491 (2 % and 2.8 %), Wolmanit CX-8 (% 1 and 2 %). Leaching studies were conducted according to AWPA E11-97. Copper analyses of leachate were determined Atomic absorption...
A Temiz, Ü C Yildiz, E D Gezer, S Yildiz, E Dizman
Supply of wooden transmission and telephone poles in Tanzania: Problems and possible solutions
1987 - IRG/WP 3424
The eucalypts which have been used widely for utility poles for more than 30 years have dwindled remarkably from traditional supply areas. Consequently, pole-using authorities are considering importing poles from abroad. This alternative is considered unrealistic and costly. The aims of this paper are: - to dispel fears of pole scarcity and to show that an abundant resource of a variety of tree sp...
K K Murira, S A Diwani
Natural decay resistance of some lesser known /used timber species from the forests of Tanzania
2005 - IRG/WP 05-10557
In order to manage the Tropical forest in a sustainable manner and increase the resource base for their wood industries, many Tropical African timber producing countries including Tanzania are promoting the many lesser known/used timbers in their forests as alternative sources of wood to the over-exploited primary timber species. Four lesser known/utilized timber species from the forests of Tanzan...
S A Amartey, P R Gillah, R C Ishengoma, J Gabriel, D H Kitojo
Whitewood - An external joinery timber?
1975 - IRG/WP 253
The timber used traditionally for softwood joinery in the UK is redwood (Pinus sylvestris). In the past its ready availability in the desired sizes and quality and its durability in service encouraged little competition. However, the past decade has seen some erosion of this position, particularly through the increased proportion of sapwood in redwood supplies. Since the sapwood is less durable th...
J W W Morgan
Speciation of leachates from CCA-treated wood
2005 - IRG/WP 05-50224-27
Different species of arsenic and chromium are characterized by different toxicities and different mobilities. The environmental impacts of CCA-treated wood would therefore be a function of the chemical forms of the metal releases. As a consequence a series of tasks were undertaken to evaluate arsenic and chromium species from CCA-treated wood. The intent of these tasks was to quantify the total...
H M Solo-Gabriele, T G Townsend, Yong Cai, B I Khan, Jin-Kun Song, J Jambeck, B Dubey, Yong-Chul Jang
The use of lap-joints in natural durability testing: moisture content development during 36 months outside exposure trials
2000 - IRG/WP 00-20217
Lap-joint trials (following European Standard ENV 12037) were set up with 11 different softwood and hardwood species. The main aim was to evaluate the suitability of this test standard (developed for testing wood preservative effectiveness) for natural durability testing. The moisture development has been followed during a 36 months period. In this paper, the outcomes of different moisture content...
H Militz, C J Bloom
Leaching of components from CCF treated timber in ground contact
1998 - IRG/WP 98-50108
In order to investigate the depletion of different CCF-salts during service small stakes (10*10*450mm³) were treated with five water-borne wood preservatives and after fixation brought into ground contact for several years. After failing some of the broken down stakes were used to determine the remaining concentration of relevant ions and their distribution in different segments of the stakes.
A...
E Melcher
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
Ability of heartwood extractives to inhibit the growth of a bacterial symbiont of Teredo navalis
2000 - IRG/WP 00-10369
Shipworms are important destroyers of wood in the marine environment, and wood users have long sought methods for preventing or limiting their attack. While heavy -duty wood preservatives are highly effective against these organisms, there is increasing concern about risks to non-target organisms. This has resulted in a gradual shift away from broadly toxic materials to either alternative material...
C S Love, A R Sipe, S C Cary, J J Morrell
Changes of copper and chromium content after leaching in wood impregnated with the CCB and CB preservatives
2000 - IRG/WP 00-50147
The objective of the study was impregnated with CCB and CB preservatives pine wood of moisture content varying from 12% to 55% subjected to leaching. Losses of copper and chromium were determined for individual layers of wood up to 3 cm from the girth. The results were compared to the total amount of metals determined in water extracts. The degree of leaching of metal ions from wood of 55% moistur...
B Mazela
Long-Term Release of Arsenic, Chromium, and Copper from CCA-Treated Wood and Ash
2005 - IRG/WP 05-50227
In this study, laboratory long-term leaching studies were conducted to characterize the leaching behavior of arsenic, chromium, and copper from CCA-treated wood samples (block, chip, and sawdust) and CCA-wood ash and to determine the rate of release of the metals from the CCA wood products. The leaching solutions were periodically collected and analyzed for the concentrations of arsenic, chromium,...
Hyunmyung Yoon, Heeseok Kang, Yong-Chul Jang
Biocidal property of the phenolic fraction of ethanol extractives of Hopea parviflora heartwood
1993 - IRG/WP 93-30003
Natural resistance of some species of timber to fungal decay and insect damage (particularly termite) is ascribed toxic nature and quantity of certain chemical substances present in the cell wall of heartwood. These chemical substances generally known to be Phenolic and Polyphenolic compounds (Rao 1982). Earlier investigations on extractives were mainly in relation to resistance of timber to decay...
R V Krishnan, K S Theagarajan, H S Ananthapadmanabha, M Nagaraja Sharma, V V Prabhu, H C Nagaveni
Leaching tests on CCA-treated wood using inorganic salt solutions
1984 - IRG/WP 3310
Pinus radiata sapwood treated to approximately 10 kg/m³ with Tanalith NCA or Tanalith C-type CCA preservatives was ground to a fine powder and samples were then leached with solutions of calcium chloride, calcium nitrate, magnesium nitrate, or a mixture of potassium di-hydrogen orthophosphate and di-potassium hydrogen orthophosphate, at 0.03M-1.00M solution concentrations. Leached wood samples we...
D V Plackett
Analysis of the boron content of preservative treated oak and pitch pine heartwood before and after leaching
1992 - IRG/WP 92-3697
Studies to determine the effects, if any, of a variety of boron formulations on heartwood of English oak and American Pitch pine have been previously reported (King et al (1991)). Small wood blocks were treated, at 10°C or 45°C, with borax, polybor or Boracol 20 for periods of 1 month or 4 months then analysed or continuously leached with tap water for a period of 1 month. Reported results showe...
S McCutcheon, G M Smith, J W Palfreyman, B King
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
A new process for in situ polymerization of vinyl monomers in wood to delay boron leaching
1998 - IRG/WP 98-40110
Efforts were accelerated on effective use of boron compounds in wood preservation owing to their environmentally safe characteristics and relatively low costs in addition to their well-known high bioactivity and fire resistant properties. Although having these unique favorable properties, they are readily leachable from treated wood at humid conditions. Therefore, they had limited market for exter...
M K Yalinkilic, W Dwianto, Y Imamura, M Takahashi
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 of chromated wood preservatives through technical drying
1990 - IRG/WP 3623
Twin samples of sawn timber of Pinus sylvestris and Picea sp. were treated with copper-chromate-containing wood preservatives and subsequently kiln resp. air dried. After drying, the distribution of preservative and rate of fixation were determined. Drying of freshly treated wood in a condenser type kiln at temperatures of 60°C and 80°C and in a vacuum type kiln at 55°C with a pressure of about...
R-D Peek, H Klipp
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