SIST EN 12436:2002

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Lepila za nosilne lesene konstrukcije - Kazeinska lepila - Razvrstitev in zahteve kakovostiKlebstoffe für tragende Holzbauteile - Kaseinklebstoffe - Klassifizierung und LeistungsanforderungenColles pour structures portantes en bois - Colles caséine - Classification et exigences de performanceAdhesives for load-bearing timber structures - Casein adhesives - Classification and performance requirements91.080.20Lesene konstrukcijeTimber structures83.180LepilaAdhesivesICS:Ta slovenski standard je istoveten z:EN 12436:2001SIST EN 12436:2002en01-september-2002SIST EN 12436:2002SLOVENSKI
STANDARD



SIST EN 12436:2002



EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 12436November 2001ICS 83.180English versionAdhesives for load-bearing timber structures - Casein adhesives- Classification and performance requirementsColles pour structures portantes en bois - Colles caséine -Classification et exigences de performanceKlebstoffe für tragende Holzbauteile - Kaseinklebstoffe -Klassifizierung und LeistungsanforderungenThis European Standard was approved by CEN on 30 September 2001.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the Management Centre or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the Management Centre has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre: rue de Stassart, 36
B-1050 Brussels© 2001 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 12436:2001 ESIST EN 12436:2002



EN 12436:2001 (E)2Contentspage1Scope.42Normative references.43Terms and definitions.44Safety.45Climatic conditions.46Requirements.56.1General.56.2Resistance to shear forces.57Test report.6Annex A (normative)
Type and duration of exposure cycles.7Annex B
(normative)
Test methods for the determination of the resistance of casein adhesivefilms to mould growth.8SIST EN 12436:2002



EN 12436:2001 (E)3ForewordThis European Standard has been prepared by Technical Committee CEN/TC 193 "Adhesives", the secretariat ofwhich is held by AENOR.This European Standard shall be given the status of a national standard, either by publication of an identical text orby endorsement, at the latest by May 2002, and conflicting national standards shall be withdrawn at the latest byMay 2002.This standard gives performance requirements and test methods for casein adhesives, where they are permitted,for use under indoor conditions. It supplements EN 301 and should be used in conjunction with EN 302-1.The standard contains two normative annexes, annex A giving details of exposure cycles used before testing theloads and annex B describing test methods for the determination of the resistance of the adhesive to mould growth.According to the CEN/CENELEC Internal Regulations, the national standards organizations of the followingcountries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland,France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden,Switzerland and the United Kingdom.SIST EN 12436:2002



EN 12436:2001 (E)41 ScopeThis European Standard specifies performance requirements and the appropriate test methods for caseinadhesives for the manufacture of load-bearing wooden structures for use under indoor conditions in heated andventilated buildings.This standard is not applicable to casein adhesives used for bonding woods with a density exceeding 750 kg/m3.2 Normative referencesThis European Standard incorporates, by dated or undated reference, provisions from other publications. Thesenormative references are cited at the appropriate places in the text, and the publications are listed hereafter. Fordated references, subsequent amendments to or revisions of any of these publications apply to this EuropeanStandard only when incorporated in it by amendment or revision. For undated references the latest edition of thepublication referred to applies (including amendments).EN 301Adhesives, phenolic and aminoplastic, for load-bearing timberstructures - Classification and performance requirements.EN 302-1Adhesives for load-bearing timber structures - Polycondensationadhesives of the phenolic and aminoplastic types - Test methods -Part 1: Determination of bond strength in longitudinal shear.EN 923Adhesives — Terms and definitions.3 Terms and definitionsFor the purposes of this European Standard the terms and definitions given in EN 923 and the following apply.3.1caseinprotein precipitated from skimmed milk which, when compounded with other reactants, is used as an adhesive forwoodNOTE
Adapted from EN 923.4 SafetyPersons using this standard shall familiar with normal laboratory practice.This standard does not purport to address all the safety problems, if any, associated with its use.It is the responsibility of the user to establish safety and health practices and to ensure compliance with anyEuropean or national regulatory conditions.5 Climatic conditionsCasein adhesives are suitable for use at temperatures not exceeding 50 C and under climatic conditions of use,equivalent to 85 % relative humidity at 20 C, that result in a moisture content in softwoods and most hardwoods of20 %, and somewhat lower in wood-based panels.SIST EN 12436:2002



EN 12436:2001 (E)56 Requirements6.1 General6.1.1
The adhesive shall be supplied in the form of a dry powder, of which a minimum of 50 % shall be casein.When prepared with water only, in accordance with the manufacturer's instructions, it shall yield a homogenousliquid, free from grit, and of a consistency suitable for spreading.6.1.2
The adhesive powder shall contain a preservative in an amount which has been proved to protect againstmould contamination when tested in accordance with annex B.6.1.3
All adhesives shall be tested by the shear test (see 6.2) using bonded test specimens made from beech.Preparation and testing of the bonded test specimens shall be carried out in accordance with EN 302-1.If the adhesive is specifically claimed to be suitable for use with particular hardwood species, it shall also be testedon bonded test specimens made from that or those species.6.2 Resistance to shear forcesThe shear failing load of close contact and gap joints after the three conditioning treatments specified in annex Ashall be tested in accordance with EN 302-1 except that the test report shall be as given in clause 7 of thisstandard.a) Joints made with beechwoodThe strength of joints shall be as given in Table 1.Table 1 — Minimum failing loads for close contact joints (0,1 mm) and gap joints (1 mm ± 0,1 mm) onbeechwoodTreatment(see annex A)Minimum failing loadNClose contact jointsGap jointsA.12 0001 600A.21 2001 000A.31 6001 300b) Joints made on other hardwood speciesIf the adhesive is tested on other hardwood species (see 6.1.3) with a density not exceeding 750 kg/m3, thestrength of joints shall be as given in Table 1.SIST EN 12436:2002



EN 12436:2001 (E)67 Test reportThe following items shall be recorded in the test report:a) The adhesive:1) type and origin of the adhesive;2) batch number of the adhesive used;3) number of components and method of preparation;b) Preparation of the samples and testing procedure:1) wood density expressed in kilograms per cubic meter at 12 % moisture content;2) special treatment of the surface of the panels to be bonded;3) the method of making the bond (i.e. temperature, pressure and duration);4) time elapsed between the bonding and the preparation of test specimens;5) number of test specimens;6) conditioning cycles applied designation (treatment code from annex A);7) precise identification of the microorganisms used and whether single cultures or a mixed culture wasused;8) the rate of application of force.c) Test results:1) mean force at failure expressed in kilonewtons and rounded to the nearest 0,1 kN;2) minimum value of the breaking force observed for any valid result;3) standard deviation expressed in kilonewtons;4) coefficient of variation expressed in %;5) type of failure;6) estimate of the proportion of the tested surface covered by wood fibre (to the nearest 10 %) expressedas the mean value for all valid test results;7) date of the test;8) any other factors that may have affected the results.SIST EN 12436:2002



EN 12436:2001 (E)7Annex A(normative)Type and duration of exposure cyclesTest specimens shall be subjected to the appropriate treatments given in Table A.1.Table A.1 — Type and duration of exposure cyclesDesignationTreatmentA17 days in standard atmosphere [20/65]1)A27 days in standard atmosphere [20/65]1)7 days in humid atmosphere [20/85]2)Test specimens removed from the conditioning chamber, one by one, andtested immediately after removal.A37 days in standard atmosphere [20/65]1)7 days in humid atmosphere [20/85]2)7 days in standard atmosphere [20/65]1)Test specimens tested in the dry state1) The standard atmosphere, [20/65], is defined as a temperature of (20 ± 2) C and a relativehumidity of (65 ± 5) %.2) The humid atmosphere [20/85] is defined as a temperature of (20 ± 2) C and a relative humidityof (85 ± 5) %.SIST EN 12436:2002



EN 12436:2001 (E)8Annex B(normative)Test methods for the determination of the resistance of casein adhesivefilms to mould growthB.1
ScopeThis annex specifies methods of determining the effect of mould contamination on casein adhesive films, byexposure to cultures of selected species of mould grown on agar plates.WARNING
The following procedures use microorganisms that can constitute a health hazard. It is essentialthat these tests be carried out in properly equipped microbiological laboratories by appropriately trainedpersonnel.B.2
PrincipleThe tests for resistance of adhesi
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