Your search resulted in 796 documents. Displaying 25 entries per page.
Testing a diffusion and reaction model for the leaching of CCA components from unfixed CCA-treated wood
2002 - IRG/WP 02-50193
A previously described physical model applicable to the leaching of any substance undergoing a first-order fixation reaction with wood is applied to the leaching of CCA components from unfixed wood. Using this model and laboratory leaching experiments with small wood samples immersed in water, the diffusion coefficients and reaction rate constant of Cr6+, total Cr, Cu and As in unfixed CCA-treated...
L Waldron, P A Cooper
Highly virulent wood-rotting Basidiomycetes in cooling tower timbers
1995 - IRG/WP 95-10125
Over the past ten years most industrial cooling towers changed their water treatment systems in order to meet environmental requirements. Since this alterations wood rot attack has been reported more frequently. Several Basidiomycete fungi were isolated and determined. Amongst the most important ones are strains of Physisporinus vitreus (Pers.:Fr.) P. Karst., Phellinus contiguus (Fr.) Pat. and Don...
J Van Acker, M Stevens, V Rijckaert
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 20: Report on the inspection of specimens at Sekondi, Ghana after 48 months
1985 - IRG/WP 4116
The results of the second inspection of CCA- and CCB-treated test panels exposed at Sekondi, Ghana, in June 1980, are presented. The panels of Pinus sylvestris treated with 3% CCA are stil unattacked after 48 months. Panels treated with 10% CCA and still in test (Fagus sylvatica, Pinus sylvestris and Alstonia scholaris) are still free of attack. Locol species treated with 3% CCB have all been dest...
F F K Ampong, N Asare-Nyadu
Long term performance of CCA preservatives in ground contact
2000 - IRG/WP 00-30223
Copper-chrome-arsenate (CCA) preservatives have been use extensively in New Zealand since the mid-1950s for a wide range of ground contact uses, radiata pine being the main species treated. They have been the subject of a comprehensive field testing programme in up to five sites in New Zealand, the earliest tests being established in 1955. Main factors affecting performance have been formulation t...
M E Hedley, D R Page, B E Patterson
Positive dosage response of CCA in hardwood power poles to soft rot indicated from New South Wales soft rot survey dat
1983 - IRG/WP 3233
Experience and observation have shown that retentions of less than 16 kg/m³ in the sapwood of individual hardwood poles are unlikely to delay its deterioration sufficiently to ensure an economic performance in some instances. The higher retentions of current practice should do so subject to adequate inspection and maintenance. Increases in retentions requirements up to 35 kg/m³ more or less, dep...
A J Witheridge
Leaching of copper, chromium and arsenic from CCA-treated slash pine heartwood
1994 - IRG/WP 94-50020
Drying green slash pine with any of three high temperature drying schedules produced a product in which both the sapwood and the heartwood could be penetrated with CCA using a modified Bethell treatment schedule. Required H3 retentions were achieved in both sapwood and heartwood, from 200 litres per m³ charge uptake. Post-treatment fixation/drying was accomplished by three different regimes, incl...
M J Kennedy, G Palmer
In-ground evaluation of a copper azole wood preservative (Tanalithâ E) at a tropical Australian test site
1996 - IRG/WP 96-30100
A field trial to determine the in-ground termite and decay resistance of Pinus radiata D. Don impregnated with a copper azole formulation, TANALITHâ E, has been established at a tropical site in the Northern Territory of Australia. Four retentions of TANALITHâ E, containing 1.54, 2.08, 2.92 and 4.30 kg/m³ of Cu, are being evaluated. For comparison, Pinus radiata specimens treated to two retenti...
J W Creffield, J A Drysdale, N Chew
Bending properties of treated western hemlock plywood
1996 - IRG/WP 96-40064
This study investigated the mechanical properties of western hemlock plywood after treatment with waterborne preservatives and redrying. Unlike previously reported results for southern pine plywood, western hemlock plywood was more sensitive to redrying temperature than to preservative treatment. Generally, western hemlock plywood was affected by temperature and other variables. Losses in mechanic...
H M Barnes, A Khouadja, D E Lyon
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 4: Report of second inspection (12 months) in Australia
1979 - IRG/WP 448
Previous reports have presented full details of the treatment and installation of the test specimens in Sydney Harbour during December, 1977, and of the results of the first (6 months) inspection made during June, 1978. At the June inspection it was apparent that the plastic tubing used to make up the frames from which to suspend the specimens was inadequate for the job and not strong enough to su...
J Beesley
Isolation and identification of bacteria from CCA-treated eucalypt power transmission poles
1987 - IRG/WP 1317
Bacteria have been isolated from CCA treated Eucalyptus maculata poles which possessed characteristic bacterial decay patterns. Cultures were isolated on a number of different media which had been inoculated with a splinter of degraded wood. Primary tests indicated that most isolates belonged to the genera Pseudomonas and Bacillus. The species Pseudomonas cepacia was most frequently isolated....
G A Willoughby, A C Hayward, L E Leightley
Leaching of CCA preservative from treated timber in marine environment
2001 - IRG/WP 01-30254
Knowledge on the amount of preservatives leaching out of treated wood is essential to optimise the chemical loading in various species of timber required for different end uses. In order to gain more insight into this aspect, the residual CCA content in 40 treated timber panels belonging to 14 species removed on destruction by marine organisms from a series of durability tests conducted in Kochi w...
M V Rao, V Kuppusamy, K S Rao, L N Santhakumaran
Volumes and weights of different CCA-C treated wood poles, anchor logs and crossarms of REB at air dry condition
1996 - IRG/WP 96-40073
Researches revealed the unit volumes and weights at air-dry condition (12% MC) of different poles, anchor logs and crossarms species of REB from this world. The softwood products are lighter than hardwood products. Inversely the unit volumes of softwood poles are higher than those of hardwood poles. Red pine (Pinus resinosa), radiata pine (Pinus radiata), blue pine (Pinus wallichiana), fir (Abies ...
A K Lahiry
Leaching of CCA components from treated wood under acidic conditions
1993 - IRG/WP 93-50004
The leaching of CCA components from treated wood under acidic conditions were investigated. Western hemlock treated with three types of CCA and two levels of target retention was subjected to leaching at four different levels of pH. After leaching tests, leached samples were subjected to laboratory decay and soft rot tests. The amount of CCA components leached was dependent on acidity of leaching ...
Jae-Jin Kim, Gyu-Hyeok Kim
Artificial drying of impregnated wood
1987 - IRG/WP 3448
Sawn timber (Pinus Sylvestris) of dimension 50x150 mm was impregnated with CCA by a full-cell process. The timber was then dried in a conventional kiln or a special vacuum kiln where the timber was dried by circulating superheated steam. Drying time was 16 days and 2 days respectively. The aim of the investigation was to compare the physical appearence of the wood after drying by the two methods w...
M-L Edlund
The course of fixation of Cu-Cr-As wood preservatives
1972 - IRG/WP 307
Copper-chrome-arsenic (CCA) preservatives in contact with wood result in an instant extensive increase of pH, because of ion-exchange and adsorption reactions with the wood. During precipitation of the active elements the pH continuously increases but reaches a maximum, when all chrome is consumed. Some of the early reaction products are unstable and slowly convert via dissolution into stable comp...
S-E Dahlgren
Relative performances of DNBP and CCA wood preservatives in accelerated decay tests
1988 - IRG/WP 3496
The effectiveness of 2-sec-butyl-4,6-dinitrophenol (DNBP) was compared with that of CCA. Test blocks of Pinus patula and Eucalyptus grandis were impregnated to precisely known retentions of approximately 3, 6, and 10 kg/m³ CCA and solvent-borne DNBP respectively. They were then challenged in decay tests comprising soil burial and exposure to monocultures of Chaetomium globosum, Coriolus versicolo...
W H Schnippenkoetter, L D Abraham, A A W Baecker
Chemical analyses of IRG/COIPM INTERNATIONAL MARINE TEST (to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water) samples
1987 - IRG/WP 4114
Chemical analysis of CCA and CCB treated timber was carried out after exposure at tropical and temperate marine sites. Results indicated that losses of all elements had occurred. In particular, losses of boron were severe. Arsenic and copper were also lost. The chromium components in both formulations was the most dominant metal remaining. The results suggest that chromium modification was importa...
L E Leightley
Polyflavonoid tannins - From a cause of CCA soft-rot failure to the "missing link" between lignin and microdistribution theories
1986 - IRG/WP 3359
Polyflavonoid tannins are proven to be fast-reacting with CCA solutions and hence, to be strong competitors of the structural wood constituents for fixation of CCA preservatives. The consequence of this effect is that even relatively small amounts of tannin cause severe undertreatment of the structural wood constituents which in turn badly affects the long term durability of CCA-treated timber. Th...
A Pizzi, W E Conradie, M Bariska
The performance of water repellants on radiata pine exposed to the weather
1989 - IRG/WP 3553
The effectiveness and resistance to weathering of four water repellent treatments, a commercial timber stain, and an oil-based clear finish, was assessed using 20x20x6 mm³ samples of untreated, copper-chrome-arsenic (CCA)-treated, and tributyltin oxide (TBTO)-treated radiata pine exposed to the weather over a four month period. The water repellency of each preservative/water repellent combination...
D V Plackett, F M Cameron
Comparative environmental impact analysis of telecommunication utility poles: Treated wood and fibreglass
1999 - IRG/WP 99-50136
This study is aimed at providing the information necessary to assess the main environmental implications of different materials utilised in construction of utility poles. The study was performed on fibreglass and CCA treated poles timber. The work has been carried out by identifying and quantifying energy and materials used and wasted released during the entire life of the pole. The interactions w...
A Cugliandolo, M Onofrio, A Quaglino
Soft rot decay of Eucalyptus maculata Hook. in different soils from Queensland, Australia
1980 - IRG/WP 1113
In the present work, different Queensland soils were chosen and their gross effects on the decay of treated and untreated Eucalyptus maculata examined. The soils were also amended with various levels of phosphate to study the response of the wood decay mycota to an increasing supply of this nutrient. Phosphate amendment was chosen because of the wide-scale use of superphosphate on Queensland soils...
L E Leightley, I W Russell
Chromium on the surface of CCA-treated wood
1978 - IRG/WP 386
Chromium in solutions of CCA preservatives is predominantly in the hexavalent state (Cr VI). It is well known that Cr VI is associated with dermatitis and skin ulceration in workers handling chromium containing products and processes. When reduced to the trivalent state, however, chromium is considerably safer. An essential part, therefore, of safety procedures in any chromium - using industry is ...
C R Coggins, P Hiscocks
Effect of incising depth and density on treatment of Douglas fir, hem fir and spruce-pine-fir lumber with CCA, ACZA or ACQ
1997 - IRG/WP 97-40093
Incising markedly improves both the depth and uniformity of preservative treatment of refractory wood species, but there are few studies directly comparing the effects of incising depth and density on penetration and retention of commonly used waterborne preservatives in wood species from the western United States. The effects of two incision densities (7300 and 8900 incisions/square meter) at two...
M Anderson, J J Morrell, J E Winandy
Retention and distribution of copper/chrome/arsenic (CCA) in pressurised sap-displaced UK grown spruce and pine
1986 - IRG/WP 3366
Increment cores were taken from UK grown Scots pine (Pinus sylvestris L.), Corsican pine (Pinus nigra var. maritima Ait), Sitka Spruce (Picea sitchensis (Bong) Carr), and Norway spruce (Picea abies (L) Karst) distribution poles treated by pressurised sap-displacement using a 1.8% copper, chrome, arsenic (CCA) solution. Each increment core was sectioned radially and the copper, chrome, and arsenic ...
P D Evans, G M Smith, B King
Comparisons of differences in electrical conductivity and corrosivity between CCA-oxide and CCA-salt treated wood
1981 - IRG/WP 3178
CCA preservatives have served well in many applications throughout the world. In developed areas it is the preservative in demand for clean dry paintable surfaces with long durability. In developing areas it is widely used for economic and logistical reasons. With the current emphasis on energy resources, the CCA preservatives are gaining greater acceptance as a substitute for hydrocarbon-related ...
J A Taylor