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A case study on quality control on telephone poles as a cost saving tool in Tanzania
1987 - IRG/WP 3418
A sample of 28 CCA treated Eucalyptus poles from a lot of 2,000 poles awaiting delivery to the field, was studied to reveal the quality of treatment. Results showed a product of very poor quality. Average figures for penetration and retention were 8.4 mm and 2.2 kg/m³; these results are 66% and 91% below the required standards, respectively. Consequences of such results are estimated to amount to losses of billion of shillings.
K K Murira


Wood decay in Danish buildings
1985 - IRG/WP 1261
At Technological Institute identification of fungi and advisory activity concerning repair of damages has taken place since 1935. Statistical analyses based on material from 1982 and 1983 are compared to earlier investigations worked out by L. Harmsen. The material shows that building traditions influence the diversity and frequency of fungal species. Many fungal damages in the last decade have showed that it is very important to use timber in a suitable manner not forgetting old building traditions. The conditions of fungal attack must be analysed and followed up by improvement of constructive and chemical wood protection.
A P Koch


The effect of sapwood on the rate of deterioration of fence posts
1986 - IRG/WP 1277
In order to evaluate the effect of the presence of sapwood on the rate of deterioration of fence posts, 30 specimens with and without sapwood of Eucalyptus citriodora, Eucalyptus paniculata, Eucalyptus saligna and Eucalyptus tereticornis were exposed in three test sites in the State of São Paulo, Brazil. The results of the inspection carried out in 1985, after 5 years of exposure, are reported in the present paper.
M S Cavalcante, G A C Lopez, E S F Mucci, R G Montagna


The benefits to New Zealand of boron salt treatment of Pinus radiata
1992 - IRG/WP 92-3692
The historical reasons for New Zealand adopting boric salt diffusion of Pinus radiata are summarised, and present day processes and their associated costs are given. The biological hazards of using Pinus radiata untreated are then argued, using endemic fungal and insect species as examples, as well as a discussion of the risks from species that may yet be accidentally introduced into the country.
D J Cross


The foreign exchange situation and fate of wood preservation in Nigeria
1989 - IRG/WP 3558
Up to about 15 years ago, wood utilization industry in Nigeria gave no serious thoughts to wood preservation. After this period however, as a result of escalated local demand for sawn timber, logs with wider sapwood and mainly of secondary tree species requiring protection of the sawn timber became dominant in the local timber scene. Preservatives both for protection in and out of ground contacts were available in the past in the market and at affordable prices. However, the value of local currency which has depreciated by about 86% within 48 months has made importation of preservatives a very expensive business. The paper suggests both short-term and long-term solutions for tackling the assult on the forest conservation programme which lack of wood preservation strategy has occasioned in Nigeria.
M A Odeyinde, S C Ifebueme


Commercial potential of the four-cycle method for the impregnation of green beech sleepers in Yugoslavia
1975 - IRG/WP 347
This paper was presented to the Conference on Wood Protection held in Sarajevo (Yugoslavia) in 1973. The paper was based partially on the report prepared by J. Struhar and G. F. Franciosi, who were appointed in 1972 as FAO consultants to demonstrate the new impregnation process for green beech sleepers in Yugoslavia. The so-called 4-cycle method was developed at the State Forest Research Institute in Bratislava (Czechoslovakia). The demonstration treatment was carried out at the Kolasin plant, where the double Rueping method is currently used. Comparing the double Rueping method with the 4-cycle method, the author discusses the possibility of introducing the new method into existing impregnation plants in Yugoslavia. Analysis has shown that the production costs of impregnated beech sleepers under the new method would cost 44 Dinars per m³ more for sleepers, or 530,000 Dinars annually (based on the Kolasin plant capacity). On the other hand, formation of tyloses and doat in "white" sleepers during seasoning, estimated to be 10%, would be completely avoided, saving 972,000 Dinars annually at the Kolasin plant. Besides the stock of untreated sleepers would be considerably reduced which would enable the saving of working capital at the Kolasin plant of about 2,5 mill of Dinars. It is also expected that due to higher creosote oil consumption and its even spreading through the wood, the service life of sleepers would be extended by 10 years (from 30 to 40). In such a way the Yugoslavian Railways would decrease the purchasing and installation costs by about 10 Dinars per m³ of sleepers or 1,270,000 Dinars annually (in 1972 USA$ 1 equalled 15 Dinars).
N Vidovic


Prevention of creosote bleeding from treated Scots pine poles
1970 - IRG/WP III 3B
Creosote, the most widely used preservative for pressure treatment of Electricity Board and GPO transmission poles in the United Kingdom has, when correctly applied, given good performance over a long period of time. Perhaps its only disadvantage as a preservative in the above fields is its tendency to exude or 'bleed' from a proportion of treated poles upon exposure to solar heat. This causes the poles to become oily making them difficult to handle during erection and maintenance and occasionally it causes annoyance to the general public who can soil clothes by brushing against such poles.
Anonymous


Proposing innovative technologies in the control of dry-wood insects
1985 - IRG/WP 1262
This paper discusses the social-economic problems involved in the biological evaluation of dry-wood insects with particular reference to Nigeria. It also discusses prospects of applying non-conventional methods of control against such insects, integrating these with the conventional preservatives as a control strategy. This discussion follows attempts made to identify the major dry-wood insects in Nigeria as a base for raising cultures required in screening wood preservative materials. Hitherto, this allimportant aspect of wood science suffered underserved relegation in Nigeria. The commonest dry-wood insects identified so far include two species of dry-wood termites (Kalotermidae) Cryptotermes havilandi (Sjostedt) and Cryptotermes brevis (Walker); and beetles Lyctus africanus Lesne (Lyctidae), Minthea rugicollis (Walker), Bostrychoplies cornutus Olivier, Xyloperthella picea Olivier, Heterobostrychus brunneus Murray, Xyloperthodea nitidipennis Murray, and Apate spp. (Bostrychidae).
M O Akanbi


A preliminary assessment of the costs of termite activity in Australia: A discussion paper
1983 - IRG/WP 1207
A preliminary assessment has been made of the economic importance of termite activity in Australia and this paper is intended to serve as a starting point in discussing this topic. Damage to timber in service represents their greatest area of economic importance in urban and rural environments. Costs resulting from termite activity include timber replacements in buildings, railway sleepers, transmission poles, termite surveys, insecticides and wood preservatives. Indirect costs are briefly discussed, as are the beneficial roles of termites in our environment.
J R J French


Wood attacking insects in urban areas in Sao Paulo State - Brazil
1985 - IRG/WP 1267
From 1974 to 1984 the investigators of Wood Division (IPT) inspected, for insect attack, more than 1,500 buildings of several kinds: commercial, residencial and historical buildings, houses and industries. In all cases, IPT was asked to give advices on control and erradication. During that time three papers concerning this problem were published (Cavalcante, 1976; De Lelis, 1978; Zanotto & Canedo, 1982). This paper, comprising partial data from the above papers, lists insects found, estimates the costs necessary to control them, and reports the most common factors that have been found favouring infestations in the inspected buildings.
P A Zanotto, M D Canedo, D A T Lelis


Recycling of impregnated timber: Part 1: Crushing, combustion plants, amount, costs and logistics
1999 - IRG/WP 99-50131
The object of the recycling research was to determine the technical and economical requirements of recycling of CCA-impregnated wood. The safest and most effective way is to crush impregnated timber in a stationary crushing plant where the reclaiming of dust is managed. The combustion techniques designed to burn solid Finnish combustible matter are applicable to burn crushed impregnated timber. Because of the arsenic scrubbing the gases is of special importance. By integrating different kinds of cleaning techniques the best collection efficiency is achieved for different kinds of impurities. The regulations for its combustion can be found in the air protection act and no limits exist for heavy metal emissions. Today, we do have to comply with the EU directives, however. In the near future a new directive for the fuel gases of a combustion plant will come into effect. lt is estimated that in the year 2000 there will be about 70,000 m3 of impregnated waste timber for recycling and the amount will grow to about 130,000 m3 before 2015. The size of the combustion plant to burn this amount of impregnated timber would be about 20 MW. Calculations made showed that the recycling of impregnated timber could be economically reasonable and the recycling payment would not be too high.
T Syrjänen


Wood preservation in Uruguay
1987 - IRG/WP 3404
The purpose of this paper is a brief description of the current status of wood treatment in Uruguay. The forest resources of the country are summarized, the environment, their economic importance and future potential. The present wood treating facilities are described, together with the chemicals used and the standards generally accepted. Wood treated products used in the Uruguayan market are cited as well as their future. Indicative figures are given on the relative prices of treated wood and its competitives like concrete or imported hardwoods, as well as of the economic incidence of treatment in the price of wood. Finally, a few words about the present status of teaching and research on wood preservation in Uruguay.
G Baillod


Wood preservation in Nigeria - Its increasing relevance, observed constraints and potential as a forest conservation option
1992 - IRG/WP 92-3732
The paper discusses the demand and supply of wood and wood products in Nigeria and points out that in view of the large population (88 million) and search for wood for housing and furniture, the demand exceeds supply. There is great shortage of industrial and domestic woods resulting in underutilization of installed machineries in forest industries and low profit margin. Under this prevailing condition, wood preservation has a definite positive role to play in reducing pressure on productive high forests and timber plantations for logs by prolonging the service life of woods in storage and in service. However, factors such as high depreciation of the local currency, Naira against the U.S. Dollar and British Pound Sterling, high cost of imported wood preservatives, low income per capita especially in the rural areas where over 70% of the population live, have tended to slow the pace of advancement of wood preservation practice in the country. With rising costs of sawn timbers and other wood products coupled with the urgent need to enhance their performance and prolong their service life, the paper concludes that wood preservation has a bright future in Nigeria. Moreover, development of less-toxic and environmentally safe wood preservatives, application of fire retardant preservatives, remedial treatment of utility poles and timbers as well as dimensional stabilization of woods will help greatly to raise the status of wood preservation in Nigeria.
M A Odeyinde, S C Ifebueme