Your search resulted in 198 documents. Displaying 25 entries per page.
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
Influence of different fixation and ageing procedures on the leaching behaviour of copper from selected wood preservatives in laboratory trials
2003 - IRG/WP 03-20264
The paper focuses on the role of different parameters, such as fixation, sample size, wood species, and leaching in internationally standardized ageing procedures for wood preservatives from Europe, Japan and the United States. The leaching protocols used were EN 84, JIS K 1571 and AWPA E11 protocols. The wood species were Scots pine, Sugi and Southern Yellow Pine respectively. Three types of com...
J Habicht, D Häntzschel, J Wittenzellner
Proposed methodology for the assessment of safety indexes
1990 - IRG/WP 3562
Safety Indexes (SI)s are developped on the same concept as Efficacy Indexes (EI)s: EIs are retentions of wood preservatives (percentages of the critical values "efficacy") which are presumed efficient for a given biological class of risk. In the same way, SIs are retentions of wood preservatives (percentages of the critical values "safety") which are taken as acceptable for human health and the ge...
Application of radio frequency heating to accelerate fixation of CCA in treated round-wood
1999 - IRG/WP 99-40133
The potential of radio frequency heating to accelerate the fixation of chromated copper arsenate (CCA) in treated round-wood was assessed. Pre-dried Douglas-fir and western red cedar round-wood sections were pressure treated with CCA in a pilot plant retort, after which they were placed individually in a pilot radio frequency (RF) chamber. Based upon the color reaction of chromotropic acid with he...
Fang Fang, J N R Ruddick
Problems of fixation of CCA-preservatives in palm-wood
1985 - IRG/WP 3338
Palm-wood may be used for posts and poles where it needs proper treatment for long time use. Based on observations by W. Killmann on low CCA-fixation in palm-wood, samples of Jubaea-palm grown in a Greenhouse at Hamburg, have been treated in two different series with a 4% solution of CCA-type B. After 1-16 weeks of storage the blocks were split into sticks of 1-2 mm² and leached. In all series 50...
H Willeitner, K Brandt
Performance of preservative-treated hardwoods with particular reference to soft rot. Report of condition of specimens installed in Victoria, Australia
1980 - IRG/WP 3155
J Beesley, R McCarthy
Quantitative assessment of the condition of field specimens
1981 - IRG/WP 2154
Suggestions for a discussion on the desirability of an extension to the existing procedure of assessment of the condition of field specimens by adding more objective, reproducible methods in order to obtain earlier and more specific information than at present on the effect of biological attack on strength and other properties of the specimens as well as the time aspect....
Accelerated fixation of CCA in borak bamboo (Bambusa balcooa Roxb.) of Bangladesh
2001 - IRG/WP 01-40193
CCA-C fixation study on impregnated (6% CCA solution), then boiled, oven-dried, normal, air-dried and steamed bamboo slices of air-dried borak bamboo (Bambusa balocca Roxb) of Bangladesh, revealed almost complete fixation in steamed (accelerated fixation) and air-dried (3 weeks, slow fixation) bamboo slices compared to moderate to slow fixation in boiled, oven-dried, normal and 24h air-dried slice...
A K Lahiry
A discussion of current theories concerning CCA fixation
1983 - IRG/WP 3238
The understanding of the fixation mechanism of CCA and related preservatives in wood has been greatly improved by a significant series of recent scientific papers. In view of recent concerns in New Zealand regarding the long-term efficacy of CCA in high decay-hazard situations, it was considered appropriate to review this recent work and to contrast it with theories presented by previous workers....
D V Plackett
Radical changes in the requirements for more safe pressure impregnation in the Nordic countries in 1988
1990 - IRG/WP 3581
After introduction of quality control schemes and standards in the Nordic countries during the seventies, the first radical change of the standards and practice of work took place after pressure from the labor unions and authorities in 1988 and 1989 in Denmark and in Sweden. A new class of preservation with less retention for out of ground contact use was introduced, fixation times were prolonged ...
Assessment of losses of wood preservatives from treated wood by leaching into the environment
1993 - IRG/WP 93-50001-13
Wood preservative chemicals may be lost from treated timber by leaching into water or soil. The degree to which this might occur and its effect on the environment is difficult to assess quantitatively due to the absence of appropriate test methods. This paper describes work to assess test methodology capable of allowing the rates of loss of wood preservative from treated timber to be quantified. T...
R J Orsler, G E Holland
nvestigation of anomalous fixation and leaching of CCA-treated red maple
2004 - IRG/WP 04-30341
The fixation of CCA-C preservative was investigated in red maple sawdust (Acer rubrum L.) at target retentions of 4.0, 6.4, 9.6 and 30.0 kg/m3. The effect of water-soluble extractives on the course of fixation was evaluated comparing the non-extracted with pre-extracted samples treated to 6.4 and 30 kg/m3. Leaching of the CCA components was monitored after complete fixation for all retentions. Fix...
S Radivojevic, P A Cooper
Multiple-Phase Pressure (MPP) Process: One-stage CCA treatment and accelerated fixation process. 5. Treatment of Sitka spruce and Scots pine
1999 - IRG/WP 99-40136
The suitability of the MPP Process for CCA treatment and accelerated fixation of species other than Radiata pine was assessed by pilot plant trials on UK-grown Sitka spruce (Picea sitchensis) and Scots pine (Pinus sylvestris). Pressure and vacuum kickbacks of spruce (14 l/m3) and Scots' pine (122 l/m3) were both substantially lower than that generated during treatment of radiata pine (369...
M E Hedley, K Nasheri, G Durbin
A simple leaching procedure for in-plant monitoring of CCA fixation
1993 - IRG/WP 93-30023
A simple leaching test is described to quantitatively estimate the extent of fixation of chromated copper arsenate (CCA) preservative treated wood products. It is based on the reaction between diphenylcarbazide and unreacted hexavalent chromium leached from borings taken from treated wood during the fixation process. The test requires about 20 minutes to complete and can be set up in a treating pl...
P A Cooper, Y T Ung
A short note on fungal decay in K33-treated poles
1982 - IRG/WP 1169
Soft rot cavities and erosion of the lumen have been found in K33-treated Pinus sylvestris poles from the years 1956-66 by microscopic studies. Poor treatment quality has been proved for some of these poles. The microscopy showed an unusual pattern of attack, and pre-treatment decay is suspected but not yet proved. Sounding the poles and using the Pilodyn indicated decay, but poking did not. Quant...
IRG test of preservative-treated hardwoods with particular reference to soft rot. Report on condition of specimens installed in Victoria, Australia
1983 - IRG/WP 3269
G C Johnson, J D Thornton
The effect of temperature on the rate of fixation of an alkyl ammonium compound (AAC) wood preservative
1984 - IRG/WP 3293
The rate of fixation of an alkyl ammonium compound wood preservative was measured by soaking samples of wood wool in various preparations of the preservative for arbitrary times followed by immediate leaching in water. The wood wool was then analysed for residual preservative. The results indicated that fixation was very rapid and increased at higher temperatures....
Accelerated wood decay in a soil bed test under greenhouse conditions compared with a stake test under field condition
1991 - IRG/WP 2384
The rate of decay of oak, beech, Douglas fir, pine and spruce stakes in an outside test field were compared with the decay rate of the same species in a greenhouse soil-bed test. Strength loss after four and six months respectively was measured by determining the compression strength parallel to the grain. The results show that all species, strength loss in the greenhouse was 2 to 4 times higher t...
J E Polman, S G Michon, H Militz
The influence of previous anti-blue-stain preservative treatments on the fixation of CC in spruce
1997 - IRG/WP 97-30134
Freshly cut and kiln dried spruce boards were treated with 4 different anti-blue stain preservatives (ABP). After a period of 10 days allowing the samples to dry and fixate, the samples were treated with CC (chromium, copper formulation) using a vacuum pressure cycle. After impregnation the wood was steam fixed. A submersion leaching test showed differences in the leachable quantity of copper and ...
M Van der Zee, W J Homan
A fixation model, based on the temperature dependence of CCA-C fixation
2000 - IRG/WP 00-40163
A model was prepared for the fixation of 1% CCA-C in red pine that allows the prediction of extent of fixation based on the temperature history of the treated wood following pressure treatment. The reaction kinetics of the rapid initial reaction and the slower main reaction were characterized using the Van t'Hoff equation. The initial reaction could be represented by a 10th order chemical...
P A Cooper, K M F Kazi, Jianbin Chen, Y T Ung
Copper naphthenate-treated Southern Pine pole stubs in field exposure. -Part 2: Chemical characterization of full size pole stubs 12 years after treatment
2000 - IRG/WP 00-30246
This study examines the influence of pre-treatment and post-treatment steaming on the character and physio-chemical nature of copper naphthenate in hydrocarbon solvent treated pine in larger, pole diameter, pole stub-length samples. This work is the continuation of two projects that began almost a decade ago. Previous reports indicated that certain morphological changes might occur in small labora...
H M Barnes, D P Kamdem, M H Freeman
CCA fixation experiments. Part 1
1989 - IRG/WP 3504
A method of squeezing solution from CCA treated wood that has not been dried at various times after treatment appears to be useful in following the fixation of CCA in wood. Experiments confirm that temperature governs the rate of fixation....
W S McNamara
Rapid leaching test
1991 - IRG/WP 2367
An accelerated test which is suitable for measuring the extent of metal fixation in both chromium and non chromium containing preservatives is described....
J A Cornfield, M Bacon, A Lyman, C Waldie, M R Gayles