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Protocol for evaluation and approving new wood preservative
1985 - IRG/WP 2159
M E Hedley, J A Butcher


AAC preservatives: Recent New Zealand and Australian experience
1982 - IRG/WP 3188
This paper outlines the present commercial situation in New Zealand, presents results of current research undertaken at FRI and CSIRO, Division of Building Research (DBR), and comments on parallel research carried out elsewhere. Finally, some general comments are made on the limitations of present technology.
J A Butcher, H Greaves


A standardised procedure for the treatment of timber with test chemicals
1986 - IRG/WP 2257
A procedure is described which allows the standardisation of sample handling and data manipulation during trials invastigating the treatability of timber with test chemicals. The use of computer software allows the data to be handled efficiently.
J Norton, A Zosars, L E Leightley


Evaluation and approval of wood preservatives in Japan
1988 - IRG/WP 2303
Japanese standardized decay test methods, performance requirements and approving system are briefly described. JIS (Japanese Industrial Standard) A 9302, which is related to a testing method for evaluating effectiveness of wood preservatives when applied to pressure treatment, is fundamentally a sand-block laboratory test method. According to performance requirements in JIS A 9201, mean percentage weight of treated wood specimens should be less than 10% and 20% of that of untreated specimens against Tyromyces palustris and Coriolus versicolor respectively. JWPA (Japan Wood Preserving Association) Standard 1 covers a testing method for assessing efficacy of wood preservatives for superficial treatment. Test procedure is basically the same as JIS A 9302, although some major modifications are adopted with regard to shape and size of wood specimens, weathering cycles and the length of forced decay. Qualitative standards require that a candidate chemical should inhibit decay keeping mean percentage weight loss of treated wood specimens less than 20% of that of untreated ones in any case as prescribed in JWPA Standard 7. Results obtained by the above methods are well discussed together with other information by Japanese Examining Board of Wood Preservatives to approve a candidate chemical as a wood preservative when an application form is submitted to the board. And then the final decision will be made by JWPA [or JTCA (Japan Termite Control Association)] if the applied chemical is acceptable for approval or not.
K Tsunoda


Wood preservation in Spain
1983 - IRG/WP 3266
This report includes some statistical data on the potential of Spanish forests and the country's timber consumption as well as detailing the extent of development of the wood products industries, and will help to give a better understanding of the use of this raw material in Spain. The main biological deteriorating organisms which damage wood are given and the capacity of the industrial treatments for preventing their damage is described, including an inventory of the vacuum/pressure and double/vacuum plants, together with the consumption of the different types of preservative used. Also the extent of wood treatment undertaken by the various industries has been analysed together with the conditions which characterize these. The homologation system that permits the manufacture of wood preservatives, their import, trade and marketing is also explained and, finally, a current list of existing standards and specifications that are used in Spain is appended. From studying this paper it can be concluded that wood preservation in Spain is characterized by: 1) under-utilization of the industrial treatment capacity available; 2) a low level of treatment, except for poles and sleepers, and consequently there is a scanty consumption of preservatives; 3) a lack of standardization; and 4) there is, in many instances, a lack of adequate laws and regulations. But looking forward, the future can be viewed with optimism and with good expectations in the coming years for an increasing development of the wood preservation industry which could result in a potential saving of timber of about 10% of the apparent yearly consumption.
A Lopez de Roma, R Cockcroft


Evaluation and approval of wood preservatives in the Nordic countries
1988 - IRG/WP 2311
This paper reviews the system for evaluating and approving the efficacy of wood preservatives for industrial use currently in force in the Nordic countries Denmark, Finland, Iceland, Norway and Sweden.
B Henningsson, J Jermer


Evaluation and approval of wood preservatives. Unification of European requirements
1988 - IRG/WP 2310
This paper reviews the current activities within the European Homologation Committee for Wood Preservatives (EHC) towards unification of the requirements on evaluation and approval of wood preservatives in Western European countries.
J Jermer


Health and safety aspects of the use of wood preservatives in Sweden
1977 - IRG/WP 396
The Act on products Hazardous to Health and to the Environment (Swedish Code of Statutes SFS 1973:329) came into force on 1st July 1973. The Act cancelled and superseded the Poison Act, the Pesticides Act and the PCB Act from 1962, 1962 and 1971 respectively. Regulations for the implementation of the Act are contained in the Ordinance on Products Hazardous to Health and to the Environment (SFS 1973:334) and also in an Amendment of the Ordinance (SFS 1973:1050). A comprehensive summary of the Act and the Ordinance prepared in common by the Swedish Ministries of Agriculture and Foreign Affairs has been deposited in the IRG/WP Secretariat. Much of the information given below as regards the Act is derived from this booklet.
B Henningsson


Wood preservation in Portugal
1985 - IRG/WP 3325
This report deals with the forest potential of Portugal and its timber industry and outlines the evolution of wood preservation in the country. The main hazards to timber in service are noted and the timbers used classified according to their natural durability and treatability. The wood preservatives used are detailed with estimates of the total consumption of the different types. Addresses are listed, of the known manufacturers and importing agencies, of the firms that treat by vacuum/pressure and those that employ the double-vacuum process, and of the organizations concerned with wood preservation research and wood preservation in general. Only two firms specialize in remedial treatments and there are two institutions which are responsible for restoring cultural properties. Information is given on requirements and approvals. The relevant standards are listed and the main Portuguese papers on wood preservation.
D De Sousa Castro Reimão, R Cockcroft


Current status of AAC preservatives in New Zealand
1980 - IRG/WP 3141
Two types of alkylammonium compounds (AAC) have been approved as commercially acceptable wood preservatives by the NZ Timber Preservation Authority (TPA). They are alkyldimethylbenzyl ammonium chloride and alkyldimethylamine acetate, both of which must contain either (a) 70% alkyl chains of C12 + C14 and less than 10% of any other individual chain length, or (b) 85% alkyl chains of C12 + C14 with no restriction on percentage occurrence of any other chain length. Existing approvals cover formulations of the quaternary ammonium compound and of the tertiary, amine salt. Approvals for use are currently restricted to Pinus radiata and to those commodities which do not involve ground contact. For interior building timbers (Commodity Specification C8), where protection is required only against insects, the minimum charge retentions and core loadings are: Alkyldimethylbenzyl ammonium chloride: 1.5 kg/m³ and 0.1% w/w; Alkyldimethylamine acetate: 1.0 kg/m³ and 0.07% w/w.
J A Butcher


Wood Preservation in the Federal Republic of Germany
1981 - IRG/WP 3157
The report gives some statistics about the forest products industries in the Federal Republic and a general review of the wood preservation industry. The trend in the use of wooden railway sleepers is decreasing, as is the use of poles. The sale of other pre-treated timber, mainly fence posts, palisades and domestic fences, is however slightly increasing. Apart from the use of pressure treatments for poles and sleepers, dipping, deluging and spraying are the most common methods of treatment used. For constructional timbers the treatment given is often only of a poor quality. A glossary of the treatments used is given and a list of the firms supplying approved preservatives. Information is given for applicants who wish to have preservatives approved for use in the Federal Republic. All wood preservatives have to be registered for the treatment of any constructional timber which relates to the strength of a building. New types of biocides will obtain approval only after special tests have been carried out to ensure their long term effectiveness. The approved State Laboratories which can issue test certificates and organizations which can give useful advice to users of treated wood are listed, together with the addresses of some other organizations. The report lists all the relevant German standards.
R Cockcroft, H Willeitner


Wood Preservation in Belgium
1981 - IRG/WP 3170
The report reviews wood preservation activities in Belgium and notes the number of authorized treatment depots has doubled during the past five years. It lists the timbers that are allowed to be used for joinery and constructional building purposes and the preservatives and treatments with which these timbers may be protected. In Belgium not only have the wood preservative product and its treatment method to be approved, but the depot where the timber is to be treated has to be authorized as well. Belgian procedures for approving the use of a preservative are detailed, together with the various chemicals that have been accepted, and the concentrations at which these may be used. A survey has indicated that during 1980 four times as much sawn timber and joinery were treated by long term immersion with water-borne preservatives than were impregnated under pressure, although of the total sawn timber treated nearly 60% was treated with organic solvent preservative either by deluging or dipping. The report lists the various brands of wood preservative products, together with their relevant specifications, which have been authorized and the names and addresses of the treatment stations with the names of the products which each employs. The organizations which influence and control wood preservation activities in the country are noted as well as the various research centres where different investigations into the subject are carried out. For wood preservation most of the Belgian Standards are derived from the European Standards.
M Stevens, R Cockcroft


Preservative treatment specifications in Fiji
1982 - IRG/WP 3190
The preservative treatment specification used in Fiji is outlined. Reference is made to a basic end use classification and to locally approved treatment processes, preservatives and retention levels. Amenability ratings are defined and penetration requirements for broad commodities indicated. Currently commercial operations rely entirely on pressure treatment with copper-chrome-arsenic multisalts and sodium arsenite - sodium pentachlorophenate formulations. The specification ie not at present mandatory, but legislation governing all aspects of commercial preservative treatment is currently being considered.
A S Alston


Benzalkonium chloride (an AAC preservative): Criteria for approval, performance in service, and implications for the future
1985 - IRG/WP 3328
The data base generated for benzalkonium chloride was considered adequate for commercial approvals, particularly after revision in late 1982. Field trials, although not part of the approval criteria, generally supported commercial use; decay observed in one test (post and rails) after 6 years' exposure would have resulted in some caution in setting retentions. No laboratory trial, nor field trial, could have predicted the problems experienced during commercial operations. Substandard treatment was interpreted as being responsible for most of the insect attack and decay problems. The remainder were caused by misuse in service, depletion (by chemical or, less likely, by biological mechanisms) during long-term wet storage, or attack by apparently highly AAC-tolerant Coniophora spp. A strict protocol for preservative approvals is now being drawn up which will reflect a higher degree of conservatism and much more reliance on long-term field trials, even of above-ground commodities.
J A Butcher


Administration of wood preservative usage in New Zealand
1977 - IRG/WP 395
Principal administration of the preservative treatment of timber in New Zealand is by the Timber Preservation Authority (TPA). The TPA was established in 1955 by Act of Parliament and is under the jurisdiction of the Minister of Forests who appoints its members. Its field staff are Forest Service employees. The Authority comprises twelve members and includes representatives of timber trade associations and state, local body and professional organisations who have an interest in preservative treatment and timber usage. The TPA has sole discretion in approving types of preservatives, treatment processes and standards of treatment within New Zealand. Standards of treatment of timber and timber products imported for use in the country must also meet TPA requirements. Application for licence to treat timber is made through the TPA. The applicant must provide evidence as to the efficiency and suitability of the proposed preservative treatment. He must also satisfy the Authority that he is capable of instituting and maintaining a control of preservative treatment by way of processes, inspections and tests which will ensure that every treatment will comply with regulations prescribed by the TPA. These are published in the TPA Specifications, which are mandatory for all commercially treated timber and composite timber products. Specifications stipulate approved processes, preservatives and their retentions in the various commodities treated, and the identification, by branding, of the treated timber offered for sale. There are approximately 300 authorised treatment plants in New Zealand of which 160 are vacuum pressure plants using copper/chrome/arsenic preservatives. The remainder are boron diffusion plants plus three Rueping plants. Details of all treatment charges must be entered on appropriate forms and copies forwarded each month to the Senior TPA Officer. In addition, each full cell vacuum/pressure plant must forward a monthly preservative usage reconciliation statement. Plants may be inspected by TPA field personnel at any time and samples of preservative solutions and treated timber may be removed for analysis to check compliance with Specifications. The TPA has power to revoke or suspend authorisation of treatment plants which do not meet prescribed standards of treatment. Although the TPA has exclusive control over Standards of treatment, other state departments or legislation may from time to time influence aspects of preservative use. The Department of Labour has authority to promulgate regulations or issue recommendations concerned with the safety of personnel who are exposed to the possible toxic effects of wood preservatives. The Department of Health has jurisdiction over the registration and use of all classes of poisons within New Zealand. It has authority to proscribe the use of any chemical which it considers is abnormally hazardous in the use to which it is put. In this respect, the Department of Health has supreme power to revoke approval of any wood preservative used in New Zealand. Regulations governing the use of all pesticides are contained in a bill currently before the New Zealand parliament. The bill is mainly concerned with those pesticides which are available to the casual purchaser. Although it is unlikely that any Act of Parliament based on this bill would affect commercial timber treatment, the use of certain chemicals by remedial treatment firms, chiefly for borer control, may be restricted. Those chemicals used as prophylactics during seasoning and preservatives purchased for home and farm timber treatments may be included within the scope of the bill.
M E Hedley