Your search resulted in 1142 documents. Displaying 25 entries per page.
Influence of acidification on decay processes of CCB treated wood
2004 - IRG/WP 04-10514
The phenomenon of copper tolerance by brown rot fungal strains has been known for a long period but the complete mechanism of copper tolerance by these fungi is not understood yet. Copper tolerance has previously been linked to oxalic acid excreted by copper tolerant brown rot fungal strains. This acid reacts with copper in the wood to form an insoluble and therefore less toxic copper oxalate. The...
M Humar, S A Amartey, M Šentjurc, F Pohleven
An environmental aspect relating to leachability of CCA from hardwood and softwood poles in Bangladesh
2001 - IRG/WP 01-50167
Leachability of CCA and the service performance of 8 softwood and 5 heartwood poles in service after 5 to 17 years in Bangladesh have been studied. The study included determination of retention of CCA-C in outer 6 mm zones at groundline (GL) and above groundline (AGL) along with the observation of decay and conditions of soils. The mean leaching of CCA-C derived from retention differential at GL a...
A K Lahiry
Disproportionate absorption of different constituents of CCA salts
1988 - IRG/WP 3484
Results of preliminary experiments carried out to study selective absorption of different constituents of CCA salts and sludge formation in commercial treatment, using Terminalia myriocarpa and Pinus kesia timbers, are reported in this paper. The objective of these experiments is to evolve simple and practical methods to prevent/minimise sludge formation and differential absorption of the constitu...
V R Sonti, S Sonti, B Chatterjee
Standardization of preservative treated timber species for conductor, insulator and transformer packing of REB
1996 - IRG/WP 96-40071
In order to resolve the post landing failure problem of wooden packing for conductor, insulator, transformer of REB, the names of the suitable timber species from different parts of the world, irrespective of countries of origin have been standardized along with their strength and treatability grades. The CCA treatability of some Pakistani timber species have been presented for example which was t...
A K Lahiry
An optimum schedule for treating radiata pine
1998 - IRG/WP 98-40105
New Zealand grown radiata pine was treated with copper chrome arsenate preservative using Bethell process. Four different treatment schedules were tried. Keeping the duration of pressure stage constant (either 15 minutes or 45 minutes) and increasing the duration of vacuum (from 15 minutes to 30 minutes) or keeping the duration of vacuum stage constant (either 15 minutes or 30 minutes) and increas...
R Gnanaharan, D R Page
Preservative treatment of wood by diffusion processes - Simulation of commercial treatment processes
1988 - IRG/WP 3498
Spruce (Picea abies), Scots pine (Pinus sylvestris) and birch (Betula pendula) were preservative treated by diffusion with mixtures of copper sulphate and arsenic pentoxide. The preservative was fixed after a suitable diffusion storage period by soaking in ammonia solution. A high standard of treatment could be achieved in spruce sapwood. This was attributed to its low wood density, and high wood ...
P Vinden
Performance of copper naphthenate-treated hardwoods
2001 - IRG/WP 01-30269
Copper naphthenate (CuNap) is a historically proven, commercially produced and industry utilized preservative for many wooden commodities including poles, fence posts, lumber, timber and wood shakes/shingles. Historically, most wood preservatives are tested using the sapwood of softwood species like pine (Pinus spp.) and or Douglas-fir (Pseudosuga menziesii) and even though the railroads of the wo...
H M Barnes, T L Amburgey, H M Freeman, J A Brient
Persistance of active ingredients in treated wood
1993 - IRG/WP 93-50001-20
Disposing of chemically protected waste wood implies the distinction between surface and pressure treatment. Considering that barked round-wood merely contains, after 7 months open storage, less than 30 g per ton of bark or 25 mg per ton of sapwood, depending on the type of insecticide, the bark or sapwood shavings may be incinerated normally, according to less severe legal prescriptions than for ...
E Graf, P Manser, S Rezzonico, B Zgraggen
Comparative field performance of CCA and CCA-water repellent treated Southern pine lumber
1995 - IRG/WP 95-30089
This paper describes the field performance of end-matched southern pine boards treated with either CCA type C or CCA type C containing an emulsion water repellent (WR) additive. Boards were either kiln or air-dried after treatment, constructed into decks, and exposed for over 3 years at Harrisburg, NC. During this exposure, matched boards were monitored for internal moisture content, cupping at mi...
A R Zahora
Semi-Solid State Bioremediation of CCA-Treated Wood Using Malted Barley as a Nutrient Source
2002 - IRG/WP 02-50184
Bioremediation processes for recovery and reuse of CCA-treated wood invariably increase the cost of any secondary products manufactured from the remediated fiber. Microbial remediation using either bacteria or fungi has been shown to remove heavy metals from CCA-treated southern yellow pine (SYP). In a two-step remediation process utilizing oxalic acid extraction and the metal-tolerant bacterium...
C A Clausen
Resistance of six timber species, treated with CCA and CCB, against marine borer attack in Goa waters (India)
1991 - IRG/WP 4166
Panels of Lagerstroemia speciosa, Toona ciliata, Olea dioica, Pinus insignis, Acrocarpus fraxinifolius and Borassus flabellifer, pressure-treated with a 6.6% solution of Copper-Chrome-Arsenic (CCA) and 6% solution of Copper-Chrome-Boric (CCB), were exposed along with untreated controls, in triplicate, in Goa waters to, assess their resistance to damage by marine borers. The control panels were all...
L N Santhakumaran, R V Krishnan
Environmental fate of copper-based wood preservatives in different soil substrates - Part 1: Screening of the metal adsorption potential
1998 - IRG/WP 98-50101-21 a
In treatment plants, spillage of wood preservatives onto soil may be of environmental concern. This potential soil contamination served as an objective for a screening study. Three different mineral soils, a mineral substrate and two horticultural substrates are examined for their sorptive potential of copper through mixing with wood preservative solutions.
Depending on the soil/substrate charact...
G M F Van Eetvelde, J M Mwangi, F Tack, R Hartmann, M Stevens
Efficacy of copper:propiconazole and copper:citrate systems in ground contact exposure at a site with copper tolerant fungi
2003 - IRG/WP 03-30305
Southern yellow pine (SYP) sapwood field stakes were treated with copper alone (ammoniacal copper carbonate, ACC) at four levels, or three levels of copper (1.6, 3.2, or 6.4 kgm-3, as CuO), air-dried, then re-treated with propiconazole in a light organic solvent at 0.07, 0.3, or 0.7 kgm-3 retentions. In a separate study, SYP field stakes were treated with three levels of ACC to give 6.7, 13.4 or ...
D D Nicholas, T Schultz
Interactions between water-borne preservatives and emulsion additives that influence the water repellency of wood
1991 - IRG/WP 2374
Incorporation of non-polar additives into water-borne treatments through of emulsion technology can greatly improve the physical characteristics of wood in service. Of specific interest with these emulsions is their effectiveness in reducing the rate of wood swelling. We have observed that the presence or absence of preservatives can often significantly influence the resultant effectiveness of the...
A R Zahora
A bioassay to determine preservative retention in hardwoods and southern pines
1982 - IRG/WP 2183
In this paper the author discusses and suggests a new method of evaluating preservative retention in treated woods by means of bioassays. Twelve North American species were tested with different retention levels of pentachlorophenol (PCP) and copper/chrome/arsenic (CCA) preservatives. The results observed in this work show that among other fungi, Aspergillus niger responds to both preservatives, w...
J C Moreschi
A test method to simulate above-ground exposure
1978 - IRG/WP 2112
The simulated above-ground exposure technique described is worthy of consideration as a simple procedure to determine the relative decay resistance of preservative-treated wood exposed to a moderate decay hazard. The method may readily be modified to allow testing of other materials such as plywood by simply enlarging the slots cut in the modified feeder strips. The method by no means completely s...
J A Butcher
Adequate preservative treatment of kiln dried Eucalyptus camaldulensis and Acacia mangium for tropical and subtropical wood poles
1996 - IRG/WP 96-40075
The Eucalyptus camaldulensis and Acacia mangium round timbers kiln-dried at EMC and full cell pressure treated with CCA-C ensured requisite penetration and adequate dry retention (30 kg/m³ or 4% w/w). The sufficient inherent strength, seasoning property, treatability of sapwood and heartwood equivalent to 44% of radius, natural durability of heartwood, and field investigation on service performan...
A K Lahiry
Research on wood protection at the Princes Risborough Laboratory 1975 & 1976
1977 - IRG/WP 3109
This paper is the latest of a 2-yearly series presenting a summarised account of the Laboratory's work in wood preservatives and related fields. The topics dealt with include: environmental studies on the usage of copper-chrome-arsenic and organic solvent preservatives; development of National and International Standards; recent developments in the preservation of external doors and windo...
J M Baker, R A Laidlaw, E R Miller, J G Savory
The evaluation of the effectiveness of wood preservatives by means of IUFRO's method for field tests with wooden stakes
1985 - IRG/WP 3348
Pinus elliottii and Eucalyptus saligna stakes treated with CCA-A, CCA-C, CCB, Cashew Nut Shell Oil and Benzotar solutions were exposed in seven test sites in Sao Paulo State, Brazil. After five years of exposure, between oil-borne preservatives Benzotar show better performance than CNSL (cashew nut shell liquid), and within waterborne preservatives the performance of CCB is not so good as that of ...
G A C Lopez, A M F Oliveira, E S Lepage
An observation of seasoning, preservative treatment and storing of CCA treated 30 bangladeshi hardwood species for crossarms
1995 - IRG/WP 95-40058
Observed kiln seasoning, preservative pressure treatment and storing of CCA treated 30 Bangladeshi hardwood species for crossarms. It revealed that it was very difficult to kiln season and preservative pressure treatment of thirty species together in a single charge and found that when species of different specific gravity kiln season together there occur some objectionable seasoning degrades, and...
G N M Ilias, M D Rokib-ul-Hafiz
A comparison between high and conventional incision densities for improving preservative treatment of Douglas-fir heartwood lumber
1993 - IRG/WP 93-40009
Incising is required for the preservative treatment of most wood species from the western United States; however, there is considerable debate about the density of incisions required to achieve adequate treatment. Previous studies have shown that the incision effect on treatment is relatively narrow, suggesting that incision densities should be significantly increased over current practices and st...
S T Lebow, J J Morrell
Accelerated diffusion treatment of sawn Sitka spruce grown in the UK
1986 - IRG/WP 3395
The treatment of 'green' sapwood and heartwood of Sitka spruce by diffusion methods was investigated. Steam/dip treatment processes gave increased solution uptakes and depths of penetration of copper in comparison with a simple dip treatment. Further investigation is required to reduce diffusion gradients with copper based formulations and to improve the penetration of '...
R J Murphy, D J Dickinson
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 14: Report of sixth inspection (60 months) in Australia
1983 - IRG/WP 499
The IRG/COIPM International Marine Test was installed at Goat Island, Sydney Harbour, in December, 1977. The results of inspections made at 6, 12, 24, 36 and 48 months have previously been reported. This document records the data obtained on the 16.12.82, i.e. after 60 months exposure, at which time only 4 of the test frames remained in test. The surface water temperature at the time of inspection...
L J Cookson, J E Barnacle
A comparative study of some anti-splitting devices, using Eucalyptus saligna and hybrids of Eucalyptus saligna X Eucalyptus spp poles
1983 - IRG/WP 3251
It is commom for some Brazilian wood pole users to require devices such as banding steel, to avoid or reduce splits at the end of Eucalyptus treated poles. On other hand users and manufacturers do not have data to confirm the effectiveness of the banding steel types normally used such as galvanized "Steel-Belt" and galvanized "Wire-Belt". For this reason a comparative study was carried out includi...
F C Geraldo, J A C Sodré
Microwave digestion of preserved wood for the determination of Cu, Cr, As, B and P in quality control
1991 - IRG/WP 2364
A microwave digestion method for the determination of copper, chromium, arsenic, boron and phosphorus in preserved woods is described. Samples were digested with nitric acid in pressure-relief type teflon PFA vessels by microwave heating in a commercial laboratory microwave oven. Fast, efficient and complete digestion was achieved within 29 min for 12 samples. The digestion time compared favourabl...
N Bernth, L B Sheard