1、BRITISH STANDARD BS1982-2: 1990 Fungal resistance of panel products made of or containing materials of organic origin Part2: Method for determination of resistance to cellulose-decomposing microfungi IMPORTANT NOTE. It is essential that this Part of BS1982 is read in conjunction with Part0, which is
2、 published separately.BS1982-2:1990 This British Standard, having been prepared under the directionof the Wood PreservationStandards Policy Committee, was published underthe authority ofthe BoardofBSI and comes into effecton 28 October1990 BSI11-1999 First published as BS1982 June1953 Second edition
3、 September1968 Third edition as BS1982-2 October1990 The following BSI references relate to the work on this standard: Committee referenceWPC/10 Draft for comment87/52052DC ISBN 0 580 18440 4 Committees responsible for this British Standard The preparation of this British Standard was entrusted by t
4、he Wood Preservation Standards Policy Committee (WPC/-) to Technical Committee WPC/10, upon which the following bodies were represented: Association of Consulting Scientists British Pest Control Association British Wood Preserving and Damp-proofing Association Chemical Industries Association Departm
5、ent of the Environment (Building Research Establishment) Timber Research and Development Association Amendments issued since publication Amd. No. Date CommentsBS1982-2:1990 BSI 11-1999 i Contents Page Committees responsible Inside front cover Foreword ii 1 Scope 1 2 Principle 1 3 Materials and reage
6、nts 1 4 Apparatus and facilities 2 5 Sampling 2 6 Test specimens 2 7 Preparation of test materials 3 8 Preparation of culture vessels and biological test 4 9 Post-incubation procedures 4 10 Validity of the test 5 11 Assessment of results 5 12 Test report 5 Appendix A Determination of water-holding c
7、apacity (WHC) of soil substrate 6 Appendix B Example of suitable culture vessel 7 Appendix C Rapid soil virulence test 7 Appendix D Flow chart for sizes and numbers of samples 8 Appendix E Calculations 9 Appendix F Calculation of decay susceptibility index (DSI) 9 Appendix G Example of test report i
8、ncluding table of results 10 Publication(s) referred to Inside back coverBS1982-2:1990 ii BSI 11-1999 Foreword This Part of BS1982 has been prepared under the direction of the Wood Preservation Standards Policy Committee. BS1982 was published in1968 as a single standard including three test methods.
9、 This revision provides a fuller consideration of the possible hazards to organic based panel products and has been divided into Parts to allow each method to be kept up-to-date separately. The following Parts supersede BS1982:1968 which is withdrawn. Part0: Guide to methods for determination; Part1
10、: Method for determination of resistance to wood-rotting Basidiomycetes; Part2: Method for determination of resistance to cellulose-decomposing microfungi; Part3: Methods for determination of resistance to mould or mildew. The soil burial procedure in this Part has been modified from the correspondi
11、ng method in the1968 edition by the introduction of preconditioning of the test samples at50 C. The incubation period has been extended from12 to16 weeks. The use of edge-sealed test samples has been introduced to assess the effect of attack through the edges. The test for the effect of moisture in
12、the absence of fungal attack using sterile soil has been deleted. A test for the water holding capacity of the soil substrate used has been added. WARNING. This standard calls for the use of substances and/or procedures that may be injurious to health if adequate precautions are not taken. It refers
13、 only to technical suitability and does not absolve the user from legal obligations relating to health and safety at any stage. The procedures described in this standard are intended to be carried out by qualified or other suitably trained and/or supervised personnel. Attention is also drawn to the
14、comments on health and safety in Part0 of this standard and to the caution in clause2 of this Part. Technical Committee38 Durability of wood and wood-based products of the European Committee for Standardization (CEN) has just commenced work, under a mandate from the Commission of the European Econom
15、ic Community (EEC), on the classification of biological hazards and durability of timber, performance of treated timber, and the performance testing of preservatives. With the publication of European Standards arising from this work, this Part of BS1982 will be amended, revised or withdrawn so as to
16、 remove any conflicting aspects. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary
17、of pages This document comprises a front cover, an inside front cover, pagesi andii, pages1 to10, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cov
18、er.BS1982-2:1990 BSI 11-1999 1 1 Scope This Part of BS1982 describes a method for subjecting panel products to attack by cellulose-decomposing microfungi and assessing thesignificance of the results obtained. The method is applicable to rigid sheet materials which do not disintegrate upon exposure t
19、o moisture alone. It is applicable to the determination of the inherent resistance of such panel products to attack by cellulose-decomposing microfungi or the resistance to such attack conferred by the use of preserving chemicals during manufacture or subsequently. The method of test is designed sol
20、ely to meet the above objectives and is not intended to simulate any form of conditions in service. The test results in themselves cannot be used directly to predict service life in practice. NOTEThe titles of the publications referred to in this standard are listed on the inside back cover. 2 Princ
21、iple Samples of the panel products to be tested are exposed to attack by microfungi by partial burial in a natural garden soil or in prepared semi-sterilized “compost”. These substrates are used to supply the inoculum of microfungi and the additional nutrientsthey require to permit rapid attack of l
22、igno-cellulose. Substrate moisture contents are adjusted to provide conditions suitable for fungal growth in the test samples. Controls of specified timber species are used to monitor the suitability of the substrate moisture content and the decaying activity of the microflora in it. After prescribe
23、d periods of incubation the extent of fungal attack is primarily assessed by determining the loss in mass of the test samples and controls. NOTEIn some tests mass loss may not be a wholly satisfactory criterion and may need to be supplemented by visual observations. CAUTION. The test procedures invo
24、lve handling and working with micro-organisms from natural populations which may present a health risk. Therefore, it is important that personnel trained in microbiology should perform those parts of the test involving handling infected test specimens. It is essential that such personnel are familia
25、r with the general recommendations on personnel safety given in BS2011-2.2J, in particular NationalappendixZ, and have appropriate equipment and facilities available. 3 Materials and reagents 3.1 Biological materials 3.1.1 Timber stock: species. The following shall be used for the test beech (Fagus
26、sylvatica L.) 3.1.2 Timber stock: wood quality. Use sound, straight-grained wood without knots. The beech shall be even-grained, free from tyloses and discoloration and having a growth rate of not less than2 and not more than6 annual rings per centimetre. NOTEWood that has been floated, water-stored
27、, chemically treated or steamed is not acceptable. Wood that has been kiln dried at temperatures below60 C is allowed. Information on these treatments should be obtained from the supplier. Prior to conversion to the final dimensions for immediate use, the timber shall be conditioned to a moisture co
28、ntent of12% to15%(m/m) on a dry mass basis. 3.1.3 Soil substrate. Natural top soil or a prepared soil of pH6 to8 and not containing added agrochemicals. It shall have a water holding capacity (WHC) greater than25%(m/m) when determined by the method in Appendix A. NOTEA horticultural soil of the John
29、 Innes No.1 type has been found to be suitable. If a natural soil is used, it shall have the turf or the top50mm removed and shall not be taken from a depth below200mm from the surface. It shall be passed through a sieve of nominal aperture size12.5mm to remove stones and larger soil particles. Prio
30、r to use the soil shall be stored in closed, moisture-proof containers. 3.2 Other materials and reagents Water complying with grade3 of BS3978 shall be used throughout. 3.2.1 Edge-sealant (see7.2.3), comprising the fungicide dichlofluanid at a concentration of0.3%(m/m) in beeswax. NOTEThe fungicide
31、is taken into solution in the minimum volume of white spirit and then dispersed in the molten beeswax. During preparation and use of the sealant the minimum temperature required to achieve liquidity (approximately65 C) should be used. CAUTION. It is essential that the precautions normally employed w
32、ith toxic chemicals are used during preparation and use and subsequently during handling of edge-sealed materials.BS1982-2:1990 2 BSI 11-1999 4 Apparatus and facilities Ordinary laboratory apparatus and in particular the following are required. 4.1 Facilities for vacuum filtration, comprising vacuum
33、 source, filter flask, Buchner funnel and coarse grade fitting filter papers 1) 125mm in diameter. 4.2 Ventilated drying oven, capable of being controlled at50 1 C and at103 2 C (orseparate ovens for each temperature). 4.3 Sealable containers, e.g.desiccators without desiccant. 4.4 Culture vessels.
34、These shall be made of inert material and shall be provided with ventilated lids. The depth shall be at least140mm so as to provide at least40mm below the test stakes when inserted in the substrate to a depth of80mm and adequate clearance above the top of the protruding parts of the stakes. The exac
35、t dimensions are otherwise not critical but determine the number of stakes in each vessel (which should be not less than10). An example of a suitable vessel is described inAppendix B. 4.5 Culture chamber (incubator or room), dark and capable of being maintained at28 1 C and at80%r.h. or greater. It
36、shall be provided with a water-filled tray at its base and its door shall provide a good seal. 4.6 Analytical balance, capable of weighing to the nearest0.001g. 5 Sampling A minimum of three replicate sheets of the panel product under test shall be sampled. Ensure that they are clean and as free as
37、possible from contaminant that might give misleading results. 6 Test specimens 6.1 General The test specimens consist of stakes cut from sheets of the panel product under test (clause5) or from the beech stock(3.1.1). For each test, three series of test stakes are required. a) Unsealed test stakes (
38、6.2.1) for testing the overall resistance of the test product to fungi throughout its thickness. b) Edge-sealed test stakes (6.2.2) in which the cut edges are sealed using the edge-sealant(3.2.1) so that an effective challenge by fungi arises solely through the original faces of the product. c) Edge
39、-sealed check stakes (6.2.3) used to determine changes in the mass of edge-seal caused by experimental handling but not caused by fungal attack. In addition to the test stakes cut from the test product, a series of control stakes cut from the beech stock are required. 1) Virulence control stakes (6.
40、3.1) to assess that the decaying ability of the soil substrate is of acceptable virulence and to provide a measure of comparability between tests. NOTEIf early reassurance of the virulence of the substrate is required the test procedure using cotton fabric described in Appendix C may be used. 2) Moi
41、sture monitoring stakes (6.3.2) to assess that the initial substrate moisture content level is adequate to support active fungal attack. 3) Size control and size check stakes (6.3.3) to assess the ability of the substrate microflora to cause significant attack in the time available on samples of a g
42、iven thickness and to provide a standard against which the performance of test stakes of varying thickness can be quantified. Details of the dimensions and numbers for each type of stake are given in6.2. The choice of which types of stakes are to be included in a particular test programme will depen
43、d on the nature of the test product and its history and on whether this information is available. The first part of Appendix D sets out a series of questions and answers leading to the second part of the table showing the types and numbers of stakes required. All test stakes and control stakes shall
44、 be numbered and otherwise marked to maintain stake and sheet identity. 6.2 Test stakes 6.2.1 Unsealed test stakes Four replicate stakes100mm long by10mm wide shall be cut using the whole thickness of the product from each of the three sheets of the product, after rejection of the300mm nearest to ea
45、ch of the original edges. Reject any stakes that show defects such as gaps, knot voids, veneer rupture or discontinuous adhesion. If it is intended to include artificial ageing procedures (see7.2.2) prior to exposure in the substrate, an additional series of stakes for each ageing procedure shall be
46、 prepared. 1) Whatman No.4 filter paper has been found to be suitable.BS1982-2:1990 BSI 11-1999 3 Some types of dense panel product, e.g.wood cement particleboard or those containing water-repellent additives, may fail to attain the required moisture content (see9.4). If this is a possibility, cut t
47、wo further stakes from each sheet and use them as wetting check stakes (see9.4) if required. 6.2.2 Edge-sealed test stakes A series of stakes shall be cut from each test product as described in6.2.1, for subsequent edge-sealing as described in7.2.3. 6.2.3 Edge-sealed check stakes Two replicate stake
48、s shall be cut from each of the three sheets of the test product as described in6.2.1. They shall be handled similarly to the edge-sealed test stakes except that after edge-sealing, instead of exposure to fungal attack they shall be stored in polyethylene bags under normal laboratory conditions. 6.3
49、 Control stakes NOTEUse of six virulence control stakes and six moisture monitoring stakes assumes the test to be carried out in one or two culture vessels of the type described in Appendix B. If a greater number of culture vessels is used, each vessel requires three replicates each of virulence control and moisture monitoring stakes. 6.3.1 Virulence control stakes Six stakes,100mm long by10mm wide by5mm thick, shall be cut from the beech stock(3.1.1). The longitudinal faces shall be parallel to the grain and the growth rings shall be at90 10 to the100mm 10m
