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A proposal for an international wood preservation standard
1994 - IRG/WP 94-20031
Two factors are driving the need for an international wood preservation standard. First, the global need to use our natural resources more wisely and second, the movement towards free trade exemplified by the General Agreement on Tariffs and Trade. The International Research Group on Wood Preservation is the ideal organisation to undertake the task of developing such a standard. This paper is intended to start this process. It attempts to bring together the best points of a number of national and international standards into a uniform format. Preservative penetrations and retentions for each commodity would be based on the hazard class/use category, the climate zone, the biological area, the natural durability of the heartwood of the species used, the service life required and the consequences of failure. The outline standard presented borrows heavily from the new European Standard and is presented as a possible starting point for the development of an international standard.
P I Morris


European standardization for wood preservation
1988 - IRG/WP 2321
G Castan


European standardization for wood preservation
1989 - IRG/WP 2335
G Castan


A note on testing the efficacy of wood preservatives above ground
1995 - IRG/WP 95-20078
A number of test methods have been used to evaluate the performance of wood preservatives in above ground situations. These have included EN 113 tests following natural exposure weathering (NEWT), L-joint or T-joint tests, lap-joint tests, and decking tests. A new test referred to as the A-frame test has been developed and is under evaluation. This is based on a sandwich-type test in which a thin (3.5 mm) sample is exposed outdoors between two untreated samples on a rack or A-frame. The advantages and disadvantages of these types of tests are discussed in a short note.
G R Williams, J A Drysdale, R F Fox


Wood Preservation in France. A statement of quality control early 1986
1986 - IRG/WP 3389
A statement of quality control in France early 1986 - Summary of new - Standards criteria for preservatives and treated wood - Aptitude of treated wood for use per class of biological hazard
M Romeis, G Ozanne


European standardization for wood preservation
1990 - IRG/WP 2359
G Castan


Practical consideration in developing an international hazard class standard: The hazards and risks
1996 - IRG/WP 96-20091
This paper discusses the concept of hazards and risks in relation to the way in which the hazard class philosophy may be used for international standardization. The difference between hazard and risk is considered as a basis for a simple classification of biological hazards for timber in use based upon its service environment. The paper proposes that the moderating influences within a service environment may be regarded as risks and used to classify the severity of hazard. These risks depend principally upon geographical location (climate) and design features controlled by the specifier. It is concluded that a pragmatic and simple approach could provide the best opportunity for an international agreement.
R J Orsler


Less environmental impact of wood preservatives by considering the risk of attack in addition to the hazard class system
1995 - IRG/WP 95-50040-10
Hazard classes, which are standardized in Europe in EN 335, are most useful to direct chemical wood preservation towards the organisms which may attack wood in the various fields of utilisation. However, hazard only signifies the fact that an attack may occur without considering the actual risk to attack. To minimize the application of chemicals with respect of less environmental impact it is necessary to consider both, the hazard of attack and the risk which implies the probability, how often attack may occur and how important this will be. In addition, also the consequences of the failure of a wooden commodity will influence the need of chemical wood preservation. It is therefore proposed to combine the hazard classes as specified in EN 335 or in similar non European regulations with a risk assessment including time assessment as a basis for the requirement on chemical wood preservation. For this, details are given in the paper.
H Willeitner


A risk model for termite attack in Australia
2003 - IRG/WP 03-10468
This paper describes a model to predict the risk of termite attack on a house in Australia. It is based on a survey of expert opinion and data from 5000 houses. The model gives a quantitative estimate of risk, and as such is useful for the development of risk management systems. An example of the application of such a system is given.
R H Leicester, C-H Wang, L J Cookson


Japan's comments on ISO/DIS 12583-1/2
1996 - IRG/WP 96-20101
The Japanese body for ISO TC 165 can not be accepted on the adoption of ISO/DIS 12583-1/2. The comments and suggestions of Japanese body were described.
K Suzuki


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


Second international symposium on wood preservation "The challenge safety-environment" 8-9 February 1993, Cannes-Mandelieu, France
1993 - IRG/WP 93-50001
Contains the following 34 Documents (IRG/WP 93-50001/1 - IRG/WP 93-50001/34) and 4 abstracts: A methodology for the life-cycle assessment of treated timber products (IRG/WP 93-50001/1) Initial results and observations of a model system to assess the efficacy and environmetal impact of preservative treated wood (IRG/WP 93-50001/2) Borates as wood preservatives - an environmental, health and safety perspective (IRG/WP 93-50001/3) The shower test method. A leaching test for assessing preservative losses from treated timber under simulated open storage conditions (IRG/WP 93-50001/4) A comparative study of CCA type C and B treated poles in service (IRG/WP 93-50001/5) Laboratory experiments on aerial emissions from wood treated with wood stains (IRG/WP 93-50001/6) Depletion of preservatives from treated wood: Results from laboratory, fungus cellar and field test (IRG/WP 93-50001/7) Modelling of PCP migration in the environment: Feeding the models with laboratory data (IRG/WP 93-50001/8) Programme d'études sur le pentachlorophénol (IRG/WP 93-50001/9) Système informatisé d'aide à la décision pour la gestion de la migration du pentachlorophénol dans l'environnement (IRG/WP 93-50001/10) Health hazards and environmental aspects when using Cu-HDO-containing wood preservatives in vacuum pressure plants (IRG/WP 93-50001/11) On-site test for indicative determination of leaching of components of preservatives from treated timber (IRG/WP 93-50001/12) Assessment of losses of wood preservatives from treated wood by leaching into the environment (IRG/WP 93-50001/13) Le séchage arificiel du bois. Simple opération de traitement du metériau ou méthode douce de préservation? [Wood kiln drying. Simple process of material treament or soft method of preservation?] (IRG/WP 93-50001/14) Social and economocal impact of an extension of service life resulting of an adequate preventive treatment. Application to wooden components used in urban areas with a high density of population (IRG/WP 93-50001/15) Extending the useful life of creosoted electricity distribution poles in service (IRG/WP 93-50001/16) Utilisation industrielle du bois. Préservation de la matière première par des utilisations rationnelles successives de ses propriétés (IRG/WP 93-50001/17) The potential for reuse of treated wood poles removed from service (IRG/WP 93-50001/18) Development of a commercial-scale CCA chemical sludge recycling system (IRG/WP 93-50001/19) Persistance of active ingredients in treated wood (IRG/WP 93-50001/20) Solidification - A viable option for the safe disposal of CCA treatment plant wastes (IRG/WP 93-50001/21) Microbial decomposition of salt treated wood (IRG/WP 93-50001/22) Délavabilité de bois ronds traités avec un sel CCA dans des conditions réelles de stockage. Incidence pratique de la fixation accélérée par étuvage. Impact effectif sur l'environnement (IRG/WP 93-50001/23) The microbiological treatment of chlorophenolic preservative in spent utility poles (IRG/WP 93-50001/24) The fate of salt preservatives in facility yard soils and decontamination of soils and drainage waters (IRG/WP 93-50001/25) Decomposition of biocides in aqueous media cases of MTC and TCMTB (IRG/WP 93-50001/26) Quantification des émanations de substances dans l'air ambiant a partir des bois traités (IRG/WP 93-50001/27) A voluntary system to control the usage of wood preservatives in Austria (IRG/WP 93-50001/28) Health and safety in use of antistain chemicals (IRG/WP 93-50001/29) Dutch work programme for environmental measures in wood preserving industry (IRG/WP 93-50001/30) Dutch national environmental policy strategy (NMP): Implications throughout the life cycle of treated timber and for the Dutch preservation industry (IRG/WP 93-50001/31) Eco-tax - A new threat for wood preservation? The Belgian experience (IRG/WP 93-50001/32) Inventaire des "déchets" ou produits connexes de la filière bois (IRG/WP 93-50001/33) Trends in environmental management in industry. Implications for wood preservation activities (IRG/WP 93-50001/34)
Anonymous


Work programme of CEN/TC 38 (April 1999) and European publications
1999 - IRG/WP 99-20165
Scope of the CEN/TC38: Standardization of the characteristics of natural or conferred durability of wood and its derived materials against biological agents, including the characteristics of protection products and associated processes to obtain this durability. This applies in particular to: - the identification of hazard classes-, - the test methods (wood preservatives and treated wood and wood based materials) and interpretation of the results; - the specification of wood preservatives and treated wood by classes of hazard including processes-, - quality control methods-, -terminology.
R Hüe


Assessing the performance of wood preservatives from biological tests - the European approach
1994 - IRG/WP 94-20040
The impetus for the European Standardisation Committee to undertake the development of a performance standard for characterising the effectiveness of wood preservatives from biological tests, lies in the Construction Products Directive. This is effectively the European Community law which provides the basis for Construction Products to be traded across all member states without technical or regulatory barriers and without having to undergo further testing or re-certification. The performance standard covering wood preservatives is EN 599 and it defines the performance which preservative products will be required to achieve in specific laboratory and field tests, in order to be accepted and marketed as suitable for particular conditions of use. Five hazard classes of use are defined in another standard (EN 355-1) and EN 599 lists the specific biological tests required for each hazard class, the maximum amount of the product that can be applied in each test, the need for pre-leaching or pre-ageing and the rationale for deriving a value (the biological reference value) for the minimum amount of product deemed effective in each test. The highest biological reference value determined from all the tests is defined as the critical value and it is this value which is carried forward to the standard covering treated wood (EN 351) to provide the basis for defining the minimum amount of product required for effectiveness within treated commodities. EN 599 lists the minimum testing requirements for each hazard class together with optional additional tests to provide efficacy assessment against a wider range of target pests or to increase confidence in the critical value by incorporating data from longer-term field tests. The standard also describes the requirements for marking and labelling preservative products to describe their suitability for specific uses. Work on EN 599 commenced in 1988 and its development has required negotiated agreement between the 18 member states of the CEN/CENELEC region with 12 different working languages and 3 different official languages for documentation. EN 599 is now at the final stage of submission to vote and the decision on its adoption and implementation will be announced before the end of 1994.
A F Bravery


Towards harmonisation of regional approaches for an International Standard for the approval of wood preservatives
1997 - IRG/WP 97-20122
Recent proposals from the European Standards body (CEN) for an ISO Standard on wood preservatives has initiated debate on whether there is any prospect of an acceptable common approach among ISO member countries, to a harmonised framework of hazard classes, with agreed supporting biological tests, leading to a unified rationale for demonstrating compliance with minimum performance standards for specific preservatives in specific end-uses. This paper discusses a potential framework for developing an International Standard prescribing hazard classes and the biological test methods capable of supporting a common approach to the approval or standardisation of a wood preservative system. An approach is proposed which incorporates elements of existing standards or protocols used in Europe, Japan, Australasia, South Africa and North America based on the framework of European Standard EN599 but adopting regional variants with incorporation of field testing for the suggested Hazard Classes 2, 3, 4a, 4b and 5. The proposals are intended to initiate development of a consensus process rather than to suggest a solution in itself. However, it is hoped that the framework provided will allow the discussion process to advance more effectively and harmoniously.
A F Preston, A F Bravery


Permanence of permethrin and bifenthrin in framing timbers subjected to hazard class 3 exposure
2005 - IRG/WP 05-30383
End-sealed Pinus radiata specimens measuring 235 x 90 x 35 mm were treated using a modified Lowry schedule with permethrin or bifenthrin in white spirit to Hazard Class 2 (H2) retentions. After conditioning, the specimens were exposed at 45o on north facing racks near Melbourne (Australia). Samples of the specimens were taken before installation, and after three and six months exposure. Analyses of permethrin-treated specimens revealed a considerable decrease (14-34 %) in permethrin content in the exposed outer 2 mm after 3 months. Continued exposure for an additional three months did not lead to further significant reduction in the permethrin retention of the outer 2 mm zone. Analysis of the 2-5 mm zone has shown no significant change in permethrin levels. The loss of permethrin is essentially confined to the outer 2 mm zone of the exposed surface which is thought to be caused by UV degradation and/or hydrolysis. Comparatively, bifenthrin exhibited no significant loss in the inner or outer samples, which maybe attributable to its greater chemical stability.
A C Hunt, D G Humphrey, R Wearne, L J Cookson


European standardization for wood preservation
1991 - IRG/WP 2365
Since the last IRG 21 conference in New-Zealand, there one meeting of the plenary committee and several meetings of working groups. The interprative documents prepared by CCE for expliciting the essential requirements of the CCE Directive on the construction products and specially: mechanical resistance and stability / hygiene, health and environment / safety in use are waited to valid the programme of work in the frame of the mandate officially received the 27th of September 1989. What is the advancement of the programme? Definition of biological hazard classes / Natural durability of wood / Treated wood / Performance of preservatives / Test methods
Anonymous


Sawn timber of fir (Abies alba Mill.) - Treatability and usability for the Hazard Classes 3 and 4
1999 - IRG/WP 99-40147
Within a national research project, tests on the treatability on sawn timber of fir (Abies alba Mill.) in oscillation pressure, vacuum pressure and double-vacuum processes have been worked out with 95 trunks taken from 3 different altitude levels (up to a height of 590 metres, 600 to 990 metres and over 1000 metres) and from 4 different regions of Switzerland. As the treatability of round wood can be compared with that of spruce (Picea abies L.), the sawn timber shows a considerably higher retention and penetration of the preservative. According to the standard EN 350.2 this wood can be classified into treatability class 2. With a vacuum pressure process a much better quality can be reached than with an oscillation pressure treatment. The treatability can be influenced by the origin of growth, as far as wet heart appears increasingly on a fir location; lumber with wet heart has a four times higher retention. The altitude of growth had no significant influence on the impregnation quality. The good retention and penetration of the preservative makes these wood species suitable for weather exposed outside constructions of solid wood or glued laminated timbers (for example bridges, acoustic and face protection walls, fences and toys). As the heartwood of fir is impregnated too, an adequate or even longer durability than with Scots pine (Pinus ssp.).can be obtained for treated construction wood.
E Graf, T Bör


Revised South African standards for wood preservation: Protocols for approval of wood preservatives
1995 - IRG/WP 95-20072
In 1994 the South African timber treatment industry completed its revision of the South African Bureau of Standards (SABS) Code of Practice for the preservative treatment of timber. These revisions were undertaken in parallel with changes to the SABS specifications for preservative treated timber. As a result of shortcomings in the previous wood preservative classification system which was based on exposure conditions for treated timber, the hazard classification for wood preservatives in force in South Africa has changed. The paper details the newly adopted classification system and its role within the current legislation requirements. Specific reference is made to the performance and toxicological data required for registration of a wood preservative in South Africa. Requirements in terms of an industry-approved South African Bureau of Standards (SABS) standard "product" specification and compliance with the SABS standard "treatment" specification are also discussed in more detail. Existing test requirements, protocols and procedures for approval of new wood preservatives are summarised. In addition, the paper identifies possible changes that could lead to more appropriate testing and acceptance procedures which reflect the real preservative needs of the various hazard classes.
D Conradie, P Turner, W E Conradie, A D Currie, I S J Burger


Summary report: Symposium "The challenge - Safety and Environment"
1990 - IRG/WP 3590
This summary, presented orally to the audience before the closure of the meeting, received on the principles a wide consensus. It has been written down to be submitted for presentation and discussion at the IRG/21st meeting in ROTORUA, 13-18 may 1990. It cantains summaries from Dr C R Coggins, chairman of Session I (PESTICIDES AND FORMULATIONS); Dr B Hegarty, chairman of Session II (TREATED WOOD); V N P Mathur, chairman of Session III (WASTE MANAGEMENT) and G. Ozanne, chairman of the Symposium
Anonymous


Proceedings from the wood preservation symposium "The Challenge - Safety and Environment" 19-20 February 1990, Cannes, France
1990 - IRG/WP 3600
Contains the List of Participants and the following 29 Documents (IRG/WP/3562-3590): Canadian code of good practices - Recommendations for design and operation of wood preservation facilities. (IRG/WP/3582) Current models used by the European health authorities to evaluate the vililization of active ingredients from treated wood used inside dwellings. (IRG/WP/3565) Creosote and cancer. (IRG/WP/3572) Surveillance médicale des personels exposés aux produits de préservation du bois. (IRG/WP/3588) Traitement curatif des bois en place. Hygiène et securité. (IRG/WP/3585) Point sur la réglementation et contraintes administratives. (IRG/WP/3575) The environment and the timber preservation in the Benelux countries. (IRG/WP/3580) Safe handling of solvents in relation to classification and labelling. (IRG/WP/3569) Proposed methodology for the assessment of safety indexes. (IRG/WP/3562) Determination of fixation properties by bioassays. A proposal for the assessment of safety indexes in wood protection. (IRG/WP/3566) The risk assessment process. Point of view of a biocide manufacturer. (IRG/WP/3568) Evaluation of the biocide diffusion from treated wood in indoor air. Bibliographic study. (IRG/WP/3584) Etude de l'impact d'un xénobiotique sur le milieu aquatique: Approche méthodologique. (IRG/WP/3586) The effect of acid rain on CCA treated timber. (IRG/WP/3579) Studies on the mobility of arsenic, copper and chromium in CCA-contaminated soil. (IRG/WP/3571) Radical changes in the requirements for rnore safe pressure impregnation in the Nordic countries in 1988. (IRG/WP/3581) Wood preservation and the environment: A Canadian perspective. (IRG/WP/3577) Disposal of treated wood - Canada. (IRG/WP/3563) Composting of waste building up in sawmill dipping basins. (IRG/WP/3570) Gestion des déchets dans le groupe Rhône-Poulenc. (IRG/WP/3583) Utility pole recycling and disposal in Eastern Canada. (IRG/WP/3587) Le rôle de l'expert dans l'évaluation toxicologique. (IRG/WP/3589) Modélisation sur maquette du rejet accidentel d'un gaz toxique dans l'atmosphere. (IRG/WP/3576) An example of media response to perceived environmental problems with CCA-treated wood. (IRG/WP/3564) The role of communication in the field of environment protection. A case study "Wood protection". (IRG/WP/3574) Will political initiatives stop the use of preservative-treated wood in Sweden? (IRG/WP/3578) A new preservative - A double edged sword. (IRG/WP/3573) In search of excellence, a necessary challenge. (IRG/WP/3567) Summary report: Symposium "The challenge Safety and Environment" (IRG/WP/3590)
Anonymous


Environmental situations on wood preservation industries in Japan
1995 - IRG/WP 95-50040-21
Because of environmental civil oppinions, Ministry of Agriculture, Forestry and Fisheries in Japan, reviesed "the standards for sawn lumber" in 1994. For the possibilities of the use of preservatives out of CCA, by the using of the hazard levels, new products like ACQ, DDAC and emulsified zinc-naphthenate can be used in the standards. Since 1994, the permitable limit of the arsenic in the waste water become severe to 0.1 mg/l, but untill Fev. 1997, it's possible to allow the level of 0.3 mg/l. The Wood Preservers Association in Japan considers the possibility by accerlated fixation of CCA for decreasing the level of the arsenic in waste water of wood preservation industries.
K Suzuki


Wood preservation requirements in Queensland, Australia
1983 - IRG/WP 3227
In Queensland the preservative treatment and utilization of timber must comply with the Timber Users' Protection Act. Preservative retention levels and penetration patterns must be complied with. Analytical zones are specified for removing samples for chemical analysis of preservative retention. The required retention levels have been expressed as percent weight of oven dry wood weight. This specification has allowed the same retention figures to be equally effective in preserving timber species of differing densities.
L E Leightley, M J Kennedy


Proceedings of the 3rd international wood preservation symposium "The Challenge - Safety and Environment" 6-7 February 1995, Cannes-Mandelieu, France
1995 - IRG/WP 95-50040
Contains the following 35 Documents (IRG/WP 95-50040/1 - IRG/WP 93-50040/35), conclusions (summaries of the sessions chairmen) and some poster abstracts: Le pin: Matériau à contact alimentaire [Pine wood as a material for food contact] (IRG/WP 95-50040/1); The use of a physical field model to study the effects of remedially treated timber on the growth of perennial ryegrass (Lolium perenne) and rye (Secale cereale), and the accumulation of toxic preservative constituents in Lolium perenne (IRG/WP 95-50040/2); Modèles de laboratoire et évaluation des risques. Protocole pour l'étude physiqo-chimique et toxicologique de la thermolyse de bois, de matériaux composites et de végétaux arbustifs (IRG/WP 95-50040/3); LCA examination of preservative treated timber products and alternatives; initial results (IRG/WP 95-50040/4); Life cycle analysis of utility poles. A Swiss case study (IRG/WP 95-50040/5); Environmental impact of PCP and NaPCP in the aquatic and atmospheric compartment (IRG/WP 95-50040/6); Pentachlorophenol: The non-emotional approach. Second draft: A discussion document (IRG/WP 95-50040/7); Methods for the assessment of wood preservative movement in soil (IRG/WP 95-50040/8); Cancer incidence among CCA exposed workers in the wood preserving industry (IRG/WP 95-50040/9) Less environmental impact of wood preservatives by considering the risk of attack in addition to the hazard class system (IRG/WP 95-50040/10); Quality and safety scheme for wood in food contact (IRG/WP 95-50040/11); Controlled fixation technology (IRG/WP 95-50040/12); Effect of leaching temperature and water acidity on the loss of metal elements from CCA treated timber in aquatic conditions. Part 2: Semi-industrial investigation (IRG/WP 95-50040/13); PCP in aquatic environments arising from historic contamination at wood processing and preservation sites (IRG/WP 95-50040/14); Evaluation of impact of CCA-treated wood on the marine environment (IRG/WP 95-50040/15); FIPRONIL - une nouvelle molécule insecticide Rhône Poulenc pou le PCO et la protection du bois [FIPRONIL - A new insecticide from Rhône Poulenc for PCO and wood preservation] (IRG/WP 95-50040/16); Traitement des matériaux lignocellulosiques en présence des composés halogénés (Risques toxiques des produits de combustion) (IRG/WP 95-50040/17); Emissions from the combusting of boron and fluoride containing wood (IRG/WP 95-50040/18); Formation of polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) during the combustion of impregnated wood (IRG/WP 95-50040/19); Harmonisation of technical requirements of treated wood in Europe. What can we learn from the experience in the Nordic countries? (IRG/WP 95-50040/20); Environmental situations on wood preservation industries in Japan (IRG/WP 95-50040/21) The use of light organic solvents in industrial wood preservation - an environmental perspective (IRG/WP 95-50040/22); Risk assessment and the approval of wood preservatives in the United Kingdom (IRG/WP 95-50040/23); Non agricultural biocide directive. Practical proposals of implementation in the case where biocides are wood preservatives (IRG/WP 95-50040/24); The biocides directive (IRG/WP 95-50040/25); Pentachlorophenol - The US and Canadian experience (IRG/WP 95-50040/26); Pentachlorophenol, its salts and esters; UK review of its uses in wood preservation and surface biocides (IRG/WP 95-50040/27); Exemptions from harmonization measures under Article 100a(4): The second authorization of the German ban on PCP (IRG/WP 95-50040/28); Cleaner prodiction and the wood preserving industry (IRG/WP 95-50040/29); Pest control products act. An overview of regulation of heavy duty wood preservatives (IRG/WP 95-50040/30); Assessment of the environmental impacts in life cycle analysis (IRG/WP 95-50040/31); Nouvelles techniques de lutte anti-termites à faible impact environnemental (IRG/WP 95-50040/32); Use of wood-decay fungi for disposal of PCP-treated wood (IRG/WP 95-50040/33); The collaborative developement of soil acceptance criteria for timber treatment chemicals in New Zealand (IRG/WP 95-50040/34); Sediment toxicity study of marine piles treated with CCA-C (IRG/WP 95-50040/35)
Anonymous


Studies and experiences of occurrence and development of soft rot in salt-treated poles of pine (Pinus sylvestris) installed in Swedish transmission lines in the years 1940-1945
1977 - IRG/WP 277
The present work describes the result of microscopic examinations of some 2,000 borings extracted from 20 to 23-year-old salt-treated poles (Scots pine) from the southern and central parts of Sweden. The purpose was to map out the occurrence of soft rot in Sweden and its influence on the mechanical strength of the poles as well as to contribute to the development of new and more satisfactory methods for inspection of salt-treated poles. The present work is part of a joint project on soft rot, triggered by alarming results from a series of strength tests carried out by Sydkraft AB (Schmidt and Jacobsson 1976). The following companies and institutions were involved in the project: Sydkraft AB, Svenska Reimpregnerings AB Cobra, the Royal College of Forestry, and the Technical University of Denmark.
H Friis-Hansen


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