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Utility, deterioration and preservation of marine timbers in India
2005 - IRG/WP 05-40314
Timber is extensively used in India in the marine environment for various purposes due to its several advantages over modern materials. Infact, its use is increasing in recent years, finding wider and wider applications and this scenario is not going to change in the near future. Though, the bio-deterioration problem is found very severe in tropical waters, still indigenous methods are widely employed for the protection of fishing craft and the present level of chemical treatment is well below 5% of total timber used. This is due to socio economic problems of the potential timber user groups, unavailability of treatment plants in the coastal areas, lack of awareness in user groups, etc. In this paper, types of fishing craft used in the country, timber uses in the marine environment, bio-deterioration losses, research conducted on bio-deterioration aspects at various places and methods applied for the protection of wooden structures are presented.
B Tarakanadha, M V Rao, M Balaji, P K Aggarwal, K S Rao
An appraisal of methods for environmental testing of leachates from salt-treated wood; part 1
1998 - IRG/WP 98-50115
The magnitude and diversity of leaching tests with salt-treated wood, performed by institutes as well as industry, strongly appeal for harmonisation towards one single method. That procedure should be well-defined, cost- and time-effective and moreover be extended with a clear detection and interpretation scheme. The paper(s) presented here tend to evaluate 2 existing leaching methods, the ENV 1250.2 and the EN 84, for their potential use as an environmental standard in high hazard class wood preservation. The leachates obtained are chemically examined for their patterns and levels of metal emission and are biologically screened for their releavance towards in service biomonitored samples. Upon strengthening the objectives and characteristics of the EN 84 ageing test, the results reported here justify the support and upgrading of this procedure as an early stage leaching method within the standard efficacy testing of new or renewed wood preservatives.
G M F Van Eetvelde, M Stevens, F Mahieu, H-W Wegen, A Platen
Recycling of used railroad ties via two-staged pyrolysis for fractionation of wood preservatives and bio-oil: pyrolytic characterization by TGA and Py-GC/MS
2015 - IRG/WP 15-50311
Creosote and copper naphthenate (CuNap) (in an oil carrier) treated railroad tie materials (crossties or sleepers) were initially heat-treated at 200 – 300 oC and subsequently pyrolyzed via thermogravimetric analysis (TGA) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) to recover wood preservatives and produce a higher quality bio-oil. Preservative-desorptive temperatures at 200 and 250 oC by TGA removed water and creosote (6.6 – 9.3 wt%) from the creosote-treated crosstie materials, and water and CuNap components (21.2 – 23.3 wt%) from the CuNap-treated crossties. Temperature at 300 oC removed a shoulder DTG peak at 305 - 325 oC and weight loss accounted for 25.5 wt% in the creosote-treated tie and 30.6 wt% in the CuNap-treated tie. Temperature at 200 – 300 oC by Py-GC/MS desorbed creosote-derived chemicals such as naphthalene, acenaphthene, fluorine, anthracene, fluoranthene, pyrene and other polycyclic aromatic hydrocarbon (PAHs) derived from the creosote-treated tie; and mineral oil (alkane hydrocarbons such as tetradecane, nonadecane, hexadecane and octadecane, and heptacosane) from the CuNap-treated ties. Pyrolysis of the wood tie with elevated temperature produced a high amount of carbohydrate- and lignin-derived compounds from wood ties. Fast pyrolysis of the 200 oC-treated crossties by Py-GC/MS produced a high fraction of creosote- and CuNap compounds most of which were then not subsequently recovered through fast pyrolysis of the 250 and 300 oC-treated samples. Fast pyrolysis of the thermally preservatives-removed tie samples produced high anhydrosugars such as levoglucosan and low acetic acid, furfural and ketones as well as high pyrolytic lignin-derived compounds, which shows good potential for phenolic-based chemical production. The results demonstrate that a thermal preservative-removal step (similar to a torrefaction step) can successfully remove valuable creosote and CuNap components for re-use as preservatives and subsequently supply a clean wood without significant levels of contaminant hazardous air pollutants for use as boiler fuel, more efficient pyrolysis to produce higher quality bio-oil, gasification or other uses.
Pyoungchung Kim, J Lloyd, Jae-Woo Kim, N Labbe
Efficacy of Erythropleum suaveolens (potrodom) and Distemonanthus benthamianus (bonsamdua) water extractives on the durability of five Ghanaian less used timber species of varying perviousness and retentiveness
2017 - IRG/WP 17-30705
Conventional wood preservatives are not only toxic to target bio-deterioration organisms but also to humans, other organisms and the environment. In an effort to find preservatives that are less toxic or non-toxic to man, other organisms and the environment, efficacy of branch bark and heartwood water extracts (0.65 g/ml) of Erythropleum suaveolens (potrodom) and Distemonanthus benthamianus (bonsamdua) were tested on five less used species (LUS) namely, Sterculia oblonga (ohaa), Antiaris toxicaria (kyenkyen), Canarium bediwonua), Celtis zenkeri (esa-kokoo) and Cola gigantea (watapuo) of varying perviousness and retentiveness from varying contents of hydrophobic and water-repellent extractives and/or extraneous substances in wood and/or vessels. Bonsandua extracts were more resistant to leaching, but potrodom extractives improved the durability of Canarium schweinfurthii more than bonsamdua extractives. Potrodom bark extracts could be readily employed to preserve non-recalcitrant low durability timber species such as C. schweinfurthii, and possibly recalcitrant low durability ones such as S. oblonga after some form of pre-treatment and/or under pressure conditions. Improved durability of immersed and brushed LUS was ranked as follows: C. gigantea > C. zenkeri > S. oblonga > A. toxicaria > C. schweinfurthii proving that the natural durability of timber is somewhat dependent on their level of recalcitrance from intrinsic hydrophobic and/or water-repellent extractives and/or extraneous substances. Though extracts showed reduced efficacy with time, the use of potrodom extractives for the preservation (control of pests) of non-recalcitrant low durability wood is promising.
A Asamoah, K Frimpong-Mensah, C Antwi-Boasiako
Liquefied wood polyols: Ecofriendly bio-based preservative for sustainable protection of wood from Termite attack
2018 - IRG/WP 18-10916
The major problems encountered in both indoor and outdoor utilization of wood are biological decay due to termite. The modification of wood with liquefied wood polyols has been found to be effective against termite attack. The liquefaction of wood aims to utilize woody wastes which are being generated during primary and secondary processing of wood in wood based industry. One of promising approaches to utilizing these lignocellulosic wastes is its liquefaction for developing natural products having potential to use as bio based wood preservatives against biological enemies of timber like termite. In this study, woody waste recovered from wood based industry has been liquefied in different liquefying media in defined reaction condition to produce chemically active liquid which is being as wood preservatives for protection of wood from termite. The level of impregnation of preservative in wood was estimated by determining the weight percent gain and the modification was characterized by FTIR and NMR spectroscopy. The efficacy of bio-based preservatives on treated wood against termites was evaluated. The accelerated wood sample were impregnated with liquefied wood polyols and tested as per Indian Standard No.4873:1968 in graveyard for 24 months exposure in field conditions against termite. The periodical observation has been collected and after 24 months accelerated termite test shows promising results both in visual observation and percentage weight loss as compare to initial condition and control sample. Investigation shows that percentage weight loss of accelerated treated wood sample which is ranges from 5- 20% of its initial weight. The increased termite resistance of modified wood indicates liquefied wood polyols which bio- based wood preservatives has a promising potential reagent for modification of wood against natural wood decaying agents. The liquefaction of wood opens up new avenues for utilization of woody waste for development of organic preservative which is environmental friendly and also helps in reducing carbon foot print from the Earth to provides better greener and sustainable world for coming generation.
A Kumar, A John, T S Mehra, A K Pandey, S Singh Chauhan
Bio-preservative properties of technical lignins from South African pulp mills: An investigation towards a conceptualized development of natural compound-based wood preservatives
2018 - IRG/WP 18-30724
The depletion of naturally durable timber and the risk posed by some of the conventional wood preservatives to human health and the environment continue to drive research efforts towards developing new formulations that are benign. Furthermore, the global concept of environmental sustainability aims at optimal use of resources and to comprehensively include conversion of waste to value added products. In view of these, it becomes a point of interest to utilize compounds from waste streams such as technical lignin obtainable from pulp black liquor by-products in the development of formulations to be used either as a sole material or component of wood preservatives. The incorporation of lignin into wood preservative formulations have only been previously achieved by means of a two-stage process involving fixation with metal salts, lignosulphonate copolymerisation and use of metal ammonia complexes as impregnants. However, the overall limitation of these processes is the inadaptability to industrial practice, owing to time factors, high cost of copolymerized lignins, and inability to use certain lignins. In view of the increasing global interest in green economy and environmental sustainability, the prospect of developing a natural compound-based wood preservative formulation using technical lignin alongside other natural compounds from biomaterial waste becomes invaluable. It is anticipated that the proposed preservative formulation would be suitable for a single-stage process adaptable to industrial practice. The suitability of lignin as a component in the development of the natural compound-based wood preservative depends on its properties. These properties vary with origin and isolation method. To this end, this study will investigate the bio preservative properties of technical lignin recovered from pulp black liquors (PBLs) obtained from different biomass origins and pulping processes commercially employed in the South African pulp industry.
A Alade, L Tyhoda, M Meincken
Liquefied wood polyols: a bio-based preservative for protection of wood from fungal decay
2018 - IRG/WP 18-30725
The liquefaction of wood is one of promising approaches in utilization of woody waste which is generated during primary and secondary processing of wood and liquefied wood having various application including bio-based preservatives. The biological degradation of wood due to fungi is the major problem encountered in indoor and outdoor utilization of wood. In this study, woody waste recovered from wood based industry was liquefied in phenol, glycerol and polyethylene glycol as liquefying media under defined reaction condition to produce chemically active liquid. These liquefied woods were used as preservatives and its efficacy were evaluated after impregnation of wood against fungi. The level of impregnation of preservative in wood was estimated by the weight percent gain after impregnation and the changes were characterized by FTIR and NMR spectroscopy. The melia wood samples have been impregnated with liquefied wood and untreated wood sample were also exposed to a brown rot (Polyporus meliae and Oligoporus placentus) and a white rot (Trametes hirsuta (Wulf. Ex Fr.) and Trametes versicolor (L. Ex Fr.) fungus for 16 weeks under laboratory conditions as per IS: 4873 (Part I), 2008. Investigation indicated that phenolated wood inhibited fungal growth in the wood. The fungicidal traits of phenolated wood showed higher antifungal efficacy against both white rot and brown rot of wood whereas wood samples impregnated with liquefied wood in glycerol and polyethylene glycol shows insignificant effects on growth of fungus and is similar infested as to control samples. The increased fungal resistance of phenolated wood indicates liquefied wood polyols has a promising potential for treatment of wood against natural wood decaying agents. The liquefaction of wood opens up new avenues for utilization of woody waste for development of organic preservative which is environmental friendly and also provides greener and sustainable option to the world for present and coming generation.
A Kumar, G Vijaylakshmi, S Singh Chauhan
Potenzy of Azadirachta indica heart wood extracts as wood bio-preservative against termite attack
2020 - IRG/WP 20-10972
Extractives in wood are one of the main reasons for wood resistance against bio-degradation. The chemical compositions of extractives from matured Azadirachta indica that are known to be very resistant against bio-degradation were studied to assess their role as wood preservative. Ethanol and toluene were used in the extraction of these compounds from the heartwood of Azadirahcta indica. Chemical analysis of the extracts was done using Gas Chromatography-Mass Spectrometry (GC-MS) after derivatization using N,O bis (trimethyl silyl) acetamide. The main groups of compounds identified from both extracts are fatty acids, hydrocarbons, sterols, sterol ketones, phenolics, sterol esters and waxes. The extracts obtained were used to treat sapwood of four different wood species that are known to be susceptible to bio-degradation at 12% (weight/weight) retention level. Treated samples were taken to timber graveyard for 12 months. It was observed that the extracts from Azadirachta indica used improved the resistance of these susceptible wood species to termite attack at the timber graveyard more than 70% when compared to the controls and also it was observed that removal of extractives from Azadirahcta indica significantly decreased their resistance to termite attack. Conclusively, the extractives from Azadirachta indica wood contribute greatly to the protection of susceptible wood species against termite attack.
L O Aguda, O B Olajide, O Y Aguda
Monitoring uptake and penetration of pesticides during impregnation of pine (Pinus sylvestris) and spruce (Picea abies) wood with bio-based microemulsion gel formulations
2020 - IRG/WP 20-30756
Even in dry state wood is susceptible to biological degradation. Preservation against biological decay in exposed conditions is conventionally achieved by impregnating the wood with pesticides applied at professional and industrial levels. Impregnation of wood with preservatives is a complex process that involves wood macro- and microstructure, and the physical characteristics of woods. Here we focused on pine (Pinus sylvestris), an easily impregnable species, as opposed to spruce (Picea abies), a refractory species. In this work, the two species were impregnated with commercial bio-based emulsion formulations containing insecticide and fungicide agents. Penetration and uptake of the active agents were evaluated on laboratory specimens. The impact of different modes of application, dipping, surface spraying, and vacuum-impregnation, on the retention and distance of penetration of the active agents, cypermethrin, permethrin and propiconazole was assessed by gas liquid chromatography coupled to mass spectroscopy. Due to the suitable combinations of solvents and surfactants of our bio-based emulsions of low-toxicity and minimal environmental impact, rapid wood penetration enabled high retention yields. The difference of penetrability of pine versus spruce is discussed in relation to their anatomical characteristics, and their conducting cells network. The present data demonstrate the penetration and retention performances of these bio-based formulations.
D Messaoudi, K Ruel, J-P Joseleau
Danish wood preservatives approval system with special focus on assessment of the environmental risks associated with industrial wood preservatives
2001 - IRG/WP 01-50166-01
The following is a description of the procedure used by the Danish Environmental Protection Agency to assess the environmental risks associated with preservatives used in the pressure impregnation of wood. The risk assessment covers issues considered to be of significance for the environment and which are adequately documented so as to allow an assessment. Such issues are persistence and mobility in soils, bioaccumulation and the impact on aquatic and terrestrial organisms. Unless required in special circumstances, the assessment does not apply to birds and mammals as the normal use of preservative treated wood is not expected to involve any noteworthy exposure of these groups. Approval of wood preservatives will be based on a general assessment of the environmental risk associated with the normal use of wood treated with the preservative in a realistic worst case situation. The assessment may address other aspects such as disposal and total life cycle.
Finishes for outdoor timbers
1975 - IRG/WP 378
Management of the wood and additives wastes in the wood processing industries: Problematics and technical answers review
1996 - IRG/WP 96-50073
Management pathways for pure wood subproducts are well known and used; but as soon as additives like preservatives, glues, varnishes or coatings are present within the wood wastes, their disposal or valorization becomes more tricky. The different kinds of mixed wood wastes of the wood processing industries, from the sawmill to the furniture manufacture, are identified herewith and their diversity is examined. These wastes can be classified according to their danger characteristics, taking into account the type of additives, their concentration, their availability for the environment, the physical state of the waste. Different disposal pathways are then considered. Combustion, with the possibility of energetic valorization seems the best answer for a major part of these wastes. But this is only possible if good combustion conditions are defined, so that no harmful products are emitted. Moreover, these conditions must be affordable on the technical and economical point of view. Then, some wastes cannot be burned in such a simple way, and need a larger approach, which is presented in this document.
S Mouras, G Labat, G Deroubaix
Proposed method for out-of-ground contact trials of exterior joinery protection systems
1981 - IRG/WP 2157
Methods for testing the efficacy of preservative treatments for exterior joinery are described using the format of a European Standard. Commercially used treatments applied to jointed test units (L-joints) which are then protected by conventional finishes are exposed to normal outdoor hazards out of ground contact. Assessment is made a) by determining eventual failure through decay and b) by destructive examination of replicate treated and untreated units, after increasing time intervals, rating comparative performance in terms of wood permeability increase and the progress of microbial colonisation.
J K Carey, D F Purslow, J G Savory
JWPA method for testing effectiveness of surface coatings with preservatives against decay fungi
1981 - IRG/WP 2164
In 1979 JWPA established a new method for testing effectiveness of surface coatings in accordance with practical use of preservative-treated lumber. Comparing the new testing method with JIS A 9302, a few new trials - size of wood specimen, weathering procedure, and decay-test procedure - are incorporated.
Wood preservation in Poland
2004 - IRG/WP 04-30362
Dynamic growth of market demand for wooden elements and articles, generated in Poland increase of interest in industrial preservation. Today, Poland is a substantial producer and exporter of wood made products. Majority of exported wood - approximately 70% - is scotch pine (Pinus silvestris L.), which, due to its natural durability, requires preservation.
Wood preservatives: Field tests out of ground contact. Brief survey of principles and methodology
1976 - IRG/WP 269
This paper contains the following spots: 1.: The general need for field tests. 2.: Interests and limits of field tests in ground contact. 3.: Various methods in use for out-of-ground contact field tests. 4.: Fungal cellar tests are they an alternative to above-ground decay exposure tests? 5.: Conclusions.
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 2: Report of treatment and installation in Australia
1978 - IRG/WP 440
The purpose of this test and the procedures to be followed have been fully set out in documents distributed by the International Research Group on Wood Preservation and numbered IRG/WP/414 and IRG/WP/420. The prescriptions set out in these two documents have been closely followed.
Field test evaluation of preservatives and treatment methods for fence posts
1985 - IRG/WP 3347
This work presents the field test results after fifteen years exposure of Eucalyptus saligna fence posts treated with six different preservatives and five treatment methods. All the combinations with oil-borne preservatives presented the best results and among the waterborne preservatives, the fence posts treated by immersion method were with the lowest performance in the field test.
G A C Lopez, E S Lepage
Screening potential preservatives against stain and mould fungi on pine timber in Zimbabwe
1995 - IRG/WP 95-30063
The search for environmentally and toxicologically safer chemicals for use in the timber preservative industry against stain and mould fungi has been intensified during the past few years. Results of field tests with two chemicals previously evaluated in the laboratory are presented. The conventional sodium pentachlorophenate was the more efficacious chemical against stain and mould fungi, providing up 90% control at a concentration of 2.5%. A potential alternative, Stopstain a borate-based chemical, gave results only slightly better than the untreated control timber, at a concentration of 5%. Unless the environmental cost and toxicological hazards of traditional chemicals are highlighted the newer and safer chemicals will be reluctantly accepted by industry as they are regarded as being prohibitively expensive.
A J Masuka
A suggested method to test the toxicity of wood preservatives towards the house longhorn beetle
1977 - IRG/WP 275
This method was developed in the Institute for Wood Technology in Sarajevo, Yugoslavia and is used to get quick information on the toxicity of wood preservatives against house longhorn beetle (Hylotrupes bajulus). The method can be used for superficially treated or deeply impregnated wood blocks, and by using small or normal size test material it can be used as a laboratory or field test, and also for accelerated infestation of test material out of ground contact. The paper is given to the International Research Group on Wood Preservation as a suggested method which could possibly be used as a standard. Only the laboratory test method is described.
Marine testing of selected waterborne preservatives
1987 - IRG/WP 4137
In 1978 a marine test was established at West Vancouver, B C. to determine the performance of selected waterborne preservatives. The preservatives in test were chromated-copper-arsenate (CCA-C), ammoniacal copper arsenate (ACA), a modified formulation of ACA which contained a higher copper content (modified ACA), ammoniacal copper zinc arsenate (ACZA) and ammoniacal zinc arsenate (AZA). The wood species used for the test was red pine. After eight years in test the CCA is providing excellent performance at all retentions, while the modified ACA is showing significant deterioration only at the lowest level. The ACA is performing quite well although it shows signs of surface deterioration at all retention levels. The performance of the ACZA is rated as unsatisfactory at retentions below 32 kg/m³ while AZA was considered to be unsuitable for use in the marine environment.
J N R Ruddick
Registration and approval of wood preservatives in Australia and New Zealand
2001 - IRG/WP 01-50166-06
Wood preservatives are treated as agricultural chemicals in Australia and, at the time of writing, as pesticides in New Zealand. Antisapstain products are currently considered to be agricultural chemicals in New Zealand while wood preservatives in the future will be considered as hazardous substances under the Hazardous Substances and New Organisms Act when this Act is fully implemented. They are regulated and approved for use by Government Departments under Ministers with responsibilities for agriculture and forestry and the environment: in Australia this is the Department of Agriculture Fisheries and Forestry; in New Zealand it is the Ministry of Agriculture and Forestry and, in the future, the Ministry for the Environment. Specific authorities within these Government instrumentalities control the registration and approvals procedures - the National Registration Authority (NRA) in Australia and, currently, the Pesticides Board in New Zealand. The latter situation is in a transition phase, with the Environment Risk Management Authority (ERMA) New Zealand expected to take over from the Pesticides Board by mid-2001. The NRA and the Pesticides Board require data packages that must include details of the preservative's application, chemistry, manufacture, toxicology, environmental credentials, and efficacy. The NRA administers the Agricultural and Veterinary Chemicals Code, which provides the Authority with the power to evaluate, register for use, and regulate the point of sale of a preservative. The evaluation procedure may involve Environment Australia in focusing on exposure and environmental toxicity data, the Department of Health and Aged Care in assessing toxicity to humans and the National Occupational Health and Safety Commission considering user safety aspects. Efficacy data can be obtained through testing to the Australasian Wood Preservation Committee (AWPC) Protocols. AWPC members may also act as experts in the assessment process and may also be involved in the development of national Standards. Thus, there is a ready conduit from registration and approval of a potential preservative to its incorporation for end use into day-to-day working standards.
Environmental status of wood preservation in the UK
1994 - IRG/WP 94-50018
The environmental status of wood preservatives and treated wood in the UK is summarised. The current legislatory position with respect to approvals, supply, use and waste disposal is considered. The bibliography at the end of this paper contains details of all publications referred to together with other relevant information although this cannot be exhaustive.
Testing of wood preservatives against marine borers (Part 1). Method of testing wood preservatives against marine borers (Part 2)
1971 - IRG/WP 37
P C Trussell, C C Walden
Report on the activities of the European Standardization Committee CEN/TC 38 'Methods of Testing wood preservatives'
1980 - IRG/WP 279 E