Your search resulted in 95 documents. Displaying 25 entries per page.
The effect of alternative pre-conditioning procedures on the durability of wood based board materials to decay fungi
1997 - IRG/WP 97-20105
In the biological testing of wood based board materials it has been shown that exposure of boards in a closed vessel system may lead to inaccurate results due to the build up of volatile substances that inhibit the test fungi. It is thought that this is a transitory effect of freshly manufactured boards. In the European standard for testing fungal durability of board materials which is currently u...
S F Curling, R J Murphy, J K Carey
Leaching of preservative components from pine decking treated with CCA and copper azole, and interactions of leachates with soils
2001 - IRG/WP 01-50171
Radiata pine decking was treated with CCA and copper azole preservatives to Australian H3 retention using conventional and modified Bethel schedules, and air-dried. Treated decking boards and durable hardwood controls were subjected to leaching in weather-exposed decks, and matching 19mm cubes were leached in extended AWPA E11-97 lab tests. Deck runoff and E11 leachate water was analysed after rai...
M J Kennedy, P A Collins
Evaluation of teak sawdayst Tectona grandis L Fil as a potential source to obtain a natural wood preservative in Colombia
2004 - IRG/WP 04-30356
Plantation Teak (Tectona grandis L. Fil) has been tested as a possible source of natural wood preservatives due to the known excellent durability of old-growth teak wood. Field tests (ground proximity termite and above ground simulated decking exposures) were established in Colombia in April 2003 at two different test sites with different climates (Tropical Dry and Rain forest). Teak heartwood ex...
A Castillo, Y Cabrera, A F Preston, R Morris
Comparison of two laboratory methods for screening potential anti-sapstain chemicals
1993 - IRG/WP 93-10036
Two methods were used to screen a number of potential anti-sapstain chemicals in the laboratory. In one method miniature boards of freshly felled Scots pine sapwood were dip treated with the candidate chemical, sprayed with a suspension of stainers or moulds and incubated for five weeks. In the other method antibiotic assay discs were treated with precise quantities of chemical, plated out on malt...
S M Gray, D J Dickinson
Colonization of treated and untreated ponderosa pine exposed in Hilo, Hawaii
1995 - IRG/WP 95-20068
The rate of decay in above ground exposures is largely controlled by rainfall and temperature, factors which can be used to construct a climate index of decay hazard in above ground exposures. Developers of new biocide formulations have utilized this knowledge by establishing test sites in sub-tropical regions such as the Gulf Coast of the United States. More recently, field sites have been locate...
C M Freitag, J J Morrell, K J Archer
Biodetioration and strength reductions in preservative treated aspen waferboard
1983 - IRG/WP 2195
Experimental aspen waferboards, bonded with liquid or powdered phenol formaldehyde resins and treated by various methods with a wide selection of preservatives, were tested for fungal resistance in accelerated laboratory trials. Mold growth on the surface as well as weight and strength losses due to the actions of decay fungi were determined. Testing of board strength after decay in high and moder...
E L Schmidt, H J Hall, R O Gertjejansen, R C De Groot
Inorganic preservative levels in soil under treated wood decks after 8 years natural exposure in Borås, Sweden
2005 - IRG/WP 05-50233
Inorganic preservative components (Cu, Cr and As) were measured to a depth of 150 mm under deck structures made with Scots pine lumber treated with several different wood preservatives and installed in Borås Sweden 8 years ago. Higher contaminant levels were observed mainly under the drip lines and in the top 50 mm of soil. Under CCA treated decks, soil arsenic concentrations increased from ba...
P A Cooper, Y T Ung, M-L Edlund, J Jermer
A field test on susceptibility of wood-based board materials to moulds
1989 - IRG/WP 3545
A field test on susceptibility of wood-based board materials to mould growth was carried out under practical, but severe, service-conditions. A total of 19 commercially available composite boards were investigated. It was found that all board materials tested were not completely immune to mould attack. Test results revealed that among the three main categories of wood-based boards involved, partic...
Qiao Wang, B Henningsson
Laboratory evaluation of water repellents as antisapstain treatment additives
1986 - IRG/WP 3382
Water repellent formulations consisting of five paraffin wax emulsions, three polyethylene wax emulsions, two polybutadiene resin emulsions, a polyester emulsion, and a ß-pinene polymer emulsion were subjected to water repellency tests on radiata pine sapwood. With one exception, the parafin wax emulsions were more effective water repellents than the alternative formulations and one of the paraff...
D V Plackett, C M Chittenden
Surface checking of CCA-treated radiata pine decking timber exposed to natural weathering
2000 - IRG/WP 00-40165
A field trial was established at four locations in Australia to assess the effect of CCA and CCA-wax treatment on the checking (cracking) of radiata pine decking timber exposed to natural weathering. Untreated decking timber and timber that had been pressure treated with water acted as controls. After 1 year's exposure the number and sizes of checks occurring in treated timber and control...
P D Evans, P J Beutel, C F Donnelly, R B Cunningham
Internal pressure development within Oriented Strand Board during supercritical fluid impregnation
2000 - IRG/WP 00-40175
Supercritical fluids (SCF) offer an attractive alternative to conventional treatment processes for delivering material into wood, but there are many unanswered questions concerning the technology. One major concern is the potential for the development of excessive pressure gradients in the wood that might exceed the material properties and lead to crushing or other pressure-induced damage. Previou...
G Oberdorfer, P E Humphrey, R J Leichti, J J Morrell
Impact of leachates from CCA- and copper azole-treated pine decking on soil-dwelling invertebrates
2002 - IRG/WP 02-50183
This study assessed the short-term effects on non-target soil invertebrates of leachates from a naturally durable hardwood and timber treated with two copper-based wood preservatives. Natural rainwater leachates from kwila decking, and radiata pine-decking treated with CCA or copper-azole, were collected and applied on mown lawn soil in Brisbane, Queensland. The soil study consisted of 5 treatment...
N Crumière, A House, M J Kennedy
Preliminary observations of the effect of growth ring orientation on the surface checking of flat sawn Southern pine decking
2005 - IRG/WP 05-20313
Checking in decking timber is a serious defect and methods of reducing its severity are required to ensure that wood can compete with alternative decking materials. The first aim of this research was to test the hypothesis that flat sawn Southern pine decking boards with growth rings oriented concave to the exposed surface will develop less severe checking when exposed outdoors than similarly expo...
K Urban, P D Evans
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
Diagnostics methods and routes proposalsto define selective sorting of demolition wood wastes
2001 - IRG/WP 01-50177
Wood wastes are more and more often used in different wood waste valorisation industries (panels, wood energy, cement factories, ...). These industries are in progress to include in their processes, wood wastes coming from demolition wood. A state of the art and an analysis have been made to propose : (1) diagnostics methods to carry out a classification of wood wastes on demolition sites and in t...
G Labat, E Bucket, C Fréret, G Deroubaix
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
Preliminary indications of the natural durability of Spruce bark board
1999 - IRG/WP 99-10312
A board material made from pressed bark, with no added adhesive, has been developed by Forintek's composites group and tested for durability by Forintek's treated-wood group and the University of Hawaii. This material was also manufactured with veneers in a one-step process. Since one role of bark on the tree is protection against pests and diseases, barkboard was expected to hav...
P I Morris, J K Grace, G E Troughton
Upgrading the fungal resistance of OSB
1999 - IRG/WP 99-40138
There is a perception that oriented strand board (OSB) is less resistant to fungl than plywood under conditions of moderate exposure to moisture. Douglas fir-faced plywood (DFP) has been suggested as a benchmark for acceptable durability under such conditions. This project was initiated to determine the minimum level of low-toxicity chemical treatment needed to upgrade the fungal resistance of OSB...
P I Morris, J E Clark, D Minchin, R Wellwood
Resistance of board materials against fungal decay: A comparative experiment on Kolle flask tests method and direct test method
1985 - IRG/WP 2243
Two sets of plywood (Aucoumea klaineana Pierre) 7 and 11 ply, treated by two preservatives, and untreated, were tested by two methods: 1. Kolle flask test method on malt-agar substrate according to the French standard NF B 51.295; 2. A direct test method in non sterile conditions according to DocNo: IRG/WP/2214. The exposure time far both methods was 12 weeks. After exposure, the degree of attack ...
G R Y Déon, L N Trong
Copper borate for the protection of engineered wood products
2006 - IRG/WP 06-40334
Copper borate was evaluated for use in protecting oriented strand board (OSB) from mould, decay, and termites. Aspen OSB bonded with either phenolic or isocyanate resin was treated with several formulations of copper borate at various loadings from 0.26 to 4 percent by weight. These panels were then tested to determine the impact of the preservative on mechanical properties as well as resistance ...
R Smart, W Wall
Biological Protection of Composite Panel from Moulds and Decay
2007 - IRG/WP 07-10612
Composite panels, such as oriented strand board (OSB), are widely used in house construction in North America. These structural panels are normally made of non-durable wood species and are susceptible to moulds and decay when exposed to wet conditions. Building envelope failures due to moulds, decay or poor construction practices can negatively impact the image of wood. To ensure durability of com...
Dian-Qing Yang, Xiang-Ming Wang, Hui Wan
Preliminary Observations of the Effect of Kerfing on the Surface Checking and Warping of Flat Sawn Southern Pine Decking
2007 - IRG/WP 07-20360
Checking and warping of decking timber are serious defects and methods of reducing their severity are required to ensure that wooden decking can compete with alternative decking materials. Kerfing is effective at reducing the checking and distortion of square cross-section lumber, and the checking of roundwood. In the past it has also been applied to preservative treated decking boards, however, t...
R Ratu, J Weizenegger, P Evans
Decay Resistance Properties of Hemicellulose-Extracted Oriented Strand Board
2008 - IRG/WP 08-10644
There is increasing interest in using cellulosic biomass as the basis for a renewable source of energy. Although the traditional focus has been on cellulose, researchers are also exploring the possibility of using hemicelluloses because they can be removed with hot water leaving the wood product intact for other applications. However, there is concern that removing hemicelluloses from the precur...
C Howell, J Paredes, S Shaler, J Jellison
Development of a Weatherometer to Accelerate the Surface Checking of Wood
2008 - IRG/WP 08-20388
There is significant interest in developing preservatives that are better at preventing wood from checking. Currently, however, there is no accepted test methodology for accelerating the development of checks in wood samples so information on the effectiveness of treatments at restricting checking can be obtained more quickly. This paper describes the development of a new type of weatherometer (Ac...
R Ratu, P D Evans
Emission Rates of Active Substances from Preserved Wood in Use Class 3
2008 - IRG/WP 08-50256
The evaluation of an active substance or a biocidal product under the Biocidal Products Directive (BPD) requires that an environmental risk assessment is carried out. The risk assessment for wood preservatives includes scenarios for preserved wood (e.g. cladding on a house), in which the predicted environmental concentration (PEC) in soil is calculated, using an emission rate for the active subs...
E F Baines