Your search resulted in 237 documents. Displaying 25 entries per page.
Examining environmental conditions and the biodeterioration of historic waterlogged wood: the Kolding Cog
2002 - IRG/WP 02-10441
Survival of waterlogged wood from thousands and in rare cases millions of years presents scientists with a unique opportunity to examine wood specimens which, due to select properties of the wood itself and/or the depositional environment, have not been completely degraded. This paper discusses the biodeterioration of a submerged shipwreck buried in Kolding Fjord, Denmark for the past 1000 years. Sections taken from two waterlogged timbers within the wreck site were physically evaluated to determine the extent of degradation in the timber at various depths below the sediment-water interface. The condition of the wood specimens was then compared to environmental characteristics, such as oxygen, hydrogen-ion (pH), and sulfide concentrations. The baseline of information gained from the systematic study of these timbers provides valuable information for the future storage and conservation of the shipwreck.
B A Jordan, D J Gregory, E L Schmidt
The dry rot fungus Serpula lacrymans, its growth and damaging of wood
2004 - IRG/WP 04-10511
The dry rot fungus (Serpula lacrymans) is one of the most dangerous wood rotting fungi, especially in the built environment. In our mycological laboratory more experiments with this fungus have been carried out aimed at:- its growth under stable and variable climatic conditions, - its possibility to attack either natural wood of different species and also modified wood primary pre-treated with some other fungi, aggressive chemicals and high temperatures, - its influence on the molecular and anatomical wood structure, - its influence on the acoustical, electric, strength and some other properties of decayed wood which can be applied for its identification.
Information on a project about the conditions of admissibility of wood-protecting agents in connection with environmental protection in Poland
1974 - IRG/WP 57
Wood-protecting agents are compounds acting toxically on fungi and insects. If handled improperly or carelessly, they may exert an action harmful to health and safety of men. This action is concerning: a) workers employed at the production of wood-protecting agents; b) workers employed at the impregnation, or at the transport and handling of impregnated wood; c) inhabitants of buildings with impregnated wooden elements, or which have been treated against fungi. At the suggestion of the Scientific and Technical Committee for Wood Protection, medical institutes started investigations concerning the influence of wood-protecting agents on human health. A draft has been worked out on the terms of admissibility for the use of these agents. The toxicological specification of a wood-preserving agent has to include the results of the following tests: 1) Determination of hypertoxicity LD50 per os for rats; 2) Determination of toxicity LD50 per coeliacus for rats; 3) Determination of irritant action on the eye mucosa and the skin of the rabbit; 4) Determination of allergenic action on the skin of the guinea pig; 5) Determination of injuring action by histopathological method; 6) Determination of toxicity LD50 by inhalation after 4 hours by rats, given the content of the active substance in mg in 1 litre of air; 7) Determination of the quantity of wood-protecting agents in the air, by means of the cabin method, and their disappearance. The above mentioned determinations are to be carried out according to methods generally accepted for toxicological tests. In certain cases, they have to be adapted to the requirements of the wood-protecting agents tests. As a fundamental criterior for the evaluation of wood-protecting agents in relation to toxical noxiousness we take the toxicity per os of the whole compound, expressed in mg per kg of weight of the living experimental animal (LD50). The other determinations are of complementary character, and in the case of unfavourable results, they cause the agent to be classified at a lower class than having been classified by the fundamental criterion LD50 alone. A classification of 5 degrees has been worked out for the wood-protecting agents, based on the classification of Hodge-Sterner: Degree I: hypertoxic agent (LD50: below 50 mg/kg); Degree II: toxic agent (LD50: 51-150 mg/kg); Degree III: noxious agent (LD50: 151-500 mg/kg); Degree IV: less noxious agent (LD50: 501-5000 mg/kg); Degree V: practical not noxious agent (LD50: above 5000 mg/kg). In accordance with the accepted criteria the toxicity of some wood-protecting agents is as follows: 1) Arsenic compounds - Degree I of toxicity; 2) Sodium fluoride - Degree II of toxicity; 3) Sodium fluoride + chromium salts - Degree II of toxicity; 4) Fluoride/borates + chromium salts - Degree II of toxicity; 5) Zinc fluosilicate - Degree III of toxicity; 6) Bifluorides - Degree III of toxicity; 7) Borax, boric acid - Degree V of toxicity. In Poland the use of wood-protecting agents of the Degree I of toxicity is prohibited. It is planned to withdraw from use progressively wood-protecting agents having higher degrees of toxicity. The present draft and the suggested classification are of preliminary character. They are being submitted for further investigation and discussion to the authorities concerned with health protection and environmental protection.
Effects of CCA treatment on settlement and growth of barnacles under field conditions
1998 - IRG/WP 98-50116
As part of a field experiment at seven European marine sites evaluating the effects of CCA treatments on non-target marine organisms, panels treated to nominal loadings of 12, 24 and 48 kg/m3 CCA were exposed at marine sites around the coast of Europe. Within two weeks of exposure, a heavy settlement of barnacles took place on the panels exposed intertidally in France. The intensity of settlement was measured after four weeks. It was found to vary significantly with preservative loading and this variation could be described by a positive linear regression - the higher the loading, the higher the numbers of barnacles settling. The survival and growth of barnacles was assessed after six months exposure. Observations of numbers of identified adults on test panels from other sites suggested that some species of barnacle settle preferentially on CCA-treated wood while others do not. The findings give an insight into the impact during the period of greatest potential for leaching of heavy treatments with CCA on organisms living in intimate contact with the treated surface.
S M Cragg, C Brown, R M Albuquerque, R A Eaton, P Goulletquer
Drying Rates and Mold Growth on Various Building Materials under Different Environmental Conditions
2010 - IRG/WP 10-20454
Mold growth on building materials is a major problem for homeowners. The most suitable method to control mold growth on building materials is to utilize design features, construction tools and practices that prevent moisture accumulation, and keep the wood as dry as possible. In order to achieve this, engineers and homebuilders have to know the effects of various temperature and moisture conditions on water accumulation and drying speed of various building materials, and the rates at which mold grows in a particular environment. A study was recently conducted at FPInnovations-Forintek Division to determine drying rates and corresponding mold growth on building materials such as oriented strand board (OSB), plywood, fiberboard, gypsum board, fiberglass insulation material, ceiling tile and several Canadian wood species lumber, under different environmental conditions. The results showed that, without ventilation, the sample moisture loss was slow and mold growth was found on test materials that were dried at 72% RH or higher, after 4 days. With ventilation, the drying rates of the various materials were much faster than without ventilation, and were not significantly affected by increasing the temperature from 20°C to 25°C. No mold growth was found on most materials that were dried with ventilation at 64% RH or less.
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.
The applicability of life cyle analysis and alternative methods in the wood preservation industry
1994 - IRG/WP 94-50023
In the Netherlands, several case studies have been performed using the life cycle analysis method (LCA). This type of research is aimed at an inventory and classification (sometimes including also evaluation) of the environmental impacts of a product, from the raw material to waste stage ("cradle to grave" approach). In a LCA each environmental impact is assessed in terms of, for example, mass of raw material use (kg), energy consumption (MJ), emissions (COx, NOX, SOx, etc.) and final waste (in kg). The critical point in an LCA is the definition of comparable "functional units" for similar products made of different materials with different service lifes. As the LCA method has often proved to be very complex, lime-consuming, expensive and difficult to interpret and translate into practically usefull results, alternative methods are developed. Three methods are described and compared on the basis of various examples. It is hoped that this may be of use as a starting point for further discussion on the suitability of applying the LCA on (preservative treated) timber products.
P Esser, J Cramer
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.
Loss of preservatives from treated wood during service
1992 - IRG/WP 92-3734
During the 23rd IRG conference in Harrogate the matter of preservative losses from treated wood during service was raised. We were asked to collect information in this field and ask now for help from you. Many tests have been carried out at a laboratory scale to study fixation and leaching from wood treated with different preservatives. Very little, however, is reported on losses of preservatives during service. Since these values are of great relevance regarding environmental impact and the final disposal, reuse or recycling of treated wood, it is of great importance to get as much information as possible on the amount of active ingredients lost during service life. We are convinced there are quite a lot of analytical data and additional information available in many places all over the world. It appears to be rewarding to collect those data and put them together adequately to get an astimate of the losses of the different components based on a broad scale of in service situations. This work will be done as soon as information is available and it is intended to present the results on next IRG meeting.
M-L Edlund, D Rudolph
Programme section 5, Environmental aspects
1997 - IRG/WP 97-50099
Programme section 5, Environmental aspects
1996 - IRG/WP 96-50077
The registration of wood preservatives under the Pesticides Act of 1962 in the Netherlands
1976 - IRG/WP 364
J Van der Kolk
Rules and conditions of the Ron Cockcroft Award Scheme RCA
1994 - IRG/WP 94-60025
Programme Section 5 Environmental aspects
1999 - IRG/WP 99-50138
Conditions of the Ron Cockcroft Award scheme
1997 - IRG/WP 97-60086
Regulations of pesticides (including wood preservatives) in the United States
1977 - IRG/WP 397
G B Fahlstrom
Environmental issues: Messages for the wood preservation industry
1985 - IRG/WP 3353
A review of the origins and structure of environmental legislation throughout those territories of the world where wood preservation is a major industry is given. The implications of media, industry and legislation interaction is discussed and suggestions made as to the key issues the wood preservation industry should concentrate its attentions on in the immediate future.
D G Anderson, P Waldie
Low temperature drying conditions of Pinus radiata wood for avoiding internal stain
1989 - IRG/WP 3507
It has been observed that, if in little sawmills, timber is dried with a low temperature schedule, it arrives at destination with internal sapstain besides of superficial mould. In this study, the lowest drying temperature at which wood should be exposed for sterilization, which results to be 52°C, is searched. It is not possible to avoid entrainment of pentachlorophenol, even though a waiting period of 72 hours after dipping the wood in a pentachlorophenate/borax solution before drying is considered. The residual content of pentachlorophenol in wood should be at least 400 µg/cm² or the moisture content less than 23% for avoiding the development of mould.
M C Rose
Effect of protective additives on leachability and efficacy of borate treated wood
2002 - IRG/WP 02-30290
Borate preservatives have been used extensively in many countries as an effective means for protecting wood against fungal and insect attack especially in interior environments. Under exterior conditions, borate compounds have a main disadvantage as they can be leached from treated wood as a result of their water solubility. In this study, we compared the potential of different additives for reducing the leachability of boron preservatives from treated wood. Scots pine sapwood (Pinus sylvestris) and poplar (Populus trichocarpa x deltoides) test samples were vacuum treated with 1 % BAE (Boric Acid Equivalent) disodium octaborate tetrahydrate (DOT) solutions containing various additives e.g. glycerol/glyoxal, polyvinylpyrrolidone (PVPY), a commercial resin compound and a commercial water repellent. The European Standard EN 84 was used as a leaching test for both coated and uncoated specimens. The results of chemical analysis of leachates taken at different periods showed that the use of protective additives reduces the boron leachability. The glycerol/glyoxal additive applied to treated pine sapwood showed the best performance. The percent of boron retained in uncoated pine sapwood was 26% while coated samples still retained 45% after 14 days of intense leaching. Similar tests on poplar revealed 19% and 34% for uncoated and coated samples, respectively.This represents a gain of 20 to 25% compared to pure DOT treated specimens of both wood species. Preliminary biological tests were carried out on malt agar using a miniblock technique for uncoated pine sapwood and beech, with Poria placenta and Coriolus versicolor, respectively. After six weeks of exposure to fungal attack all boron protective systems tested proved their effectiveness, as none of the test samples exhibited a mass loss exceeding 4%. The reference 1% BAE without protective additives showed an average mass loss of 15%. Finally, test data are reported of standard EN 113 testing in view of a further evaluation of the biological efficacy of combined DOT-additive treatments.
A Mohareb, J Van Acker, M Stevens
An attempt to evaluate wood resistance against fungal decay in non-sterile conditions by measuring the variation of resistance to bending test
1988 - IRG/WP 2308
The main object of this work was to determine the variation of strength on large test specimens of wood (800 x 45 x 45 mm³) when exposed to accelerated fungal attacks close to natural conditions, out of test vessels. The modulus of elasticity (MOE) and the modulus of rupture (MOR) have been assessed. Thereby, the natural resistance of the wood species to fungal decay, the efficiency of preservative as well as the treatment applied are discussed. The wood tested is a guianese secondary species (Couma guianensis). The fungi tested are two guianese strains of brown and white rot. The exposure time is 12 weeks. No mould contamination has been recorded by use of a selective fungicide. The results obtained show that it is possible to infest in nonsterile conditions large wood specimens. Furthermore, modulus of rupture appears to be the most reliable criterion. The investigation, that requires limited equipment and staff could be performed in any tropical research station as it has been done at CTFT, French Guiana center.
L N Trong
Conditions of the Ron Cockcroft Award scheme (RCA)
2003 - IRG/WP 03-60177
The role of communication in the field of environment protection: A case study "Wood Protection"
1990 - IRG/WP 3574
Conditions for membership of IRG
1994 - IRG/WP 94-60024
Trends in environmental management in industry. Implications for wood preservation activities
1993 - IRG/WP 93-50001-34
J A De Larderel
A review of environmental emissions from building and construction materials in comparison with preserved wood
2005 - IRG/WP 05-50224-11
A review of the public domain literature concerning emissions to the environment from materials which are used in the construction of buildings (e.g. Concrete, Asphalt, Galvanised Steel), in comparison with preserved wood, and a review of the approaches taken by the construction sector in assessing the risk from environmental emissions, in comparison with the approaches taken by the wood preservation sector.
E F Baines