1、| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BRITISH STANDARD BS EN 12429:1998 The Euro
2、pean Standard EN 12429:1998 has the status of a British Standard ICS 91.100.99 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Thermal insulating products for building applications Conditioning to moisture equilibrium under specified temperature and humidity conditionsThis Bri
3、tish Standard, having been prepared under the direction of the Sector Board for Building and Civil Engineering, was published under the authority of the Standards Board and comes into effect on 15 November 1998 BSI 1998 ISBN 0 580 30296 2 BS EN 12429:1998 Amendments issued since publication Amd. No.
4、 Date Text affected National foreword This British Standard is the English language version of EN 12429:1998. It is one of a large number of European test method standards which have been introduced for thermal insulating products. Guidance on the content and application of these new test methods is
5、 given in PD 6621. The UK participation in its preparation was entrusted by Technical Committee B/540, Energy performance of materials, components and buildings, to Subcommittee B/540/1, European Standards for thermal insulation, which has the responsibility to: aid enquirers to understand the text;
6、 present to the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. A list of organizations represented on this subcommittee can be obta
7、ined on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” f
8、acility of the BSI Standards Electronic Catalogue. 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 obl
9、igations. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 9 and a back cover.CEN European Committee for Standardization Comite Europe en de Normalisation Europa isches Komitee fu r Normung Central Secretariat: rue de Stassart 36, B-1050 Br
10、ussels 1998 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 12429:1998 E EUROPEAN STANDARD EN 12429 NORME EUROPE ENNE EUROPA ISCHE NORM June 1998 ICS 91.120.10 Descriptors: Thermal insulation, buildings, thermal insulating material
11、s, tests, hygroscopic tests, determination of content, humidity, specimen preparation English version Thermal insulating products for building applications Conditioning to moisture equilibrium under specified temperature and humidity conditions Produits isolants thermiques destine s aux applications
12、 du ba timent Conditionnement jusqua le quilibre hygroscopique dans des conditions de tempe rature et dhumidite spe cifie es Wa rmeda mmstoffe fu r das Bauwesen Einstellen der Ausgleichsfeuchte bei definierten Temperatur- und Feuchtebedingungen This European Standard was approved by CEN on 25 June 1
13、998. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained
14、 on application to the Central Secretariat or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretar
15、iat has the same status as the official versions. 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.Page 2 EN
16、12429:1998 BSI 1998 Foreword This European Standard has been prepared by Technical Committee CEN/TC 88, Thermal insulating materials and products, the Secretariat of which is held by DIN. This European Standard is one of a series of standards which specify test methods for determining dimensions and
17、 properties of thermal insulating materials and products. It supports a series of product standards for thermal insulating materials and products which derive from the Council Directive of 21 December 1988 on the approximation of laws, regulations and administrative provisions of the Member States r
18、elating to construction products (Directive 89/106/EEC) through the consideration of the essential requirements. This European Standard contains the following normative annex: annex A Determination of limiting value of moisture content change and conditioning time factor by experiment; and two infor
19、mative annexes: annex B Computer calculations to determine the limiting value of moisture content change; annex C Calculations of conditioning time to reach equilibrium using the Fourier number. This European Standard has been drafted for applications in buildings but it may also be used in other ar
20、eas where it is relevant. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by December 1998, and conflicting national standards shall be withdrawn at the latest by December 1998. According to the CEN/
21、CENELEC Internal Regulations, the national standards organizations of the following countries 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,
22、 Switzerland and the United Kingdom. Contents Page Foreword 2 1 Scope 3 2 Normative references 3 3 Definitions and abbreviations 3 4 Principle 3 5 Apparatus 3 6 Test specimens 4 7 Procedure 4 8 Calculation and expression of results 5 9 Accuracy 5 10 Test report 5 Annex A (normative) Determination of
23、 limiting value of moisture content change and conditioning time factor by experiment 6 Annex B (informative) Computer calculations to determine the limiting value of moisture content change 7 Annex C (informative) Calculations of conditioning time to reach equilibrium using the Fourier number 8Page
24、 3 EN 12429:1998 BSI 1998 1 Scope This European Standard specifies equipment and procedures to condition a thermal insulating product to equilibrium moisture content at (23 2)8C and (50 5) % relative humidity. The standard is also applicable to thermal insulating products with moulded skins but is n
25、ot normally relevant for faced products or for products with other surface treatments. NOTE 1 The normally specified moisture content is the result of the equilibrium between the atmosphere and the product at (23 2)8C and (50 5) % relative humidity. The standard may also be used if a product has to
26、be conditioned to other relative humidities. NOTE 2 The moisture equilibrium may due to hysteresis effects differ depending on whether the equilibrium has been reached by absorption or by desorption. In addition, perfect equilibrium may require a very long time to be reached. Therefore it is necessa
27、ry to accept equilibrium within a certain accuracy. NOTE 3 For products which do not absorb moisture, conditioning is not needed. It should nevertheless be ensured that there is no water on the surface before testing. 2 Normative references This European Standard incorporates, by dated or undated re
28、ference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of these publications apply to this draft European Standard only when incorpo
29、rated in it by amendment or revision. For undated references the latest edition of the publication referred to applies. EN 12085, Thermal insulating products for building applications Determination of linear dimensions of test specimens. prEN ISO 12571, Building materials Determination of hygroscopi
30、c sorption curves (ISO/DIS 12571:1996). 3 Definitions and abbreviations 3.1 Definitions For the purposes of this standard, the following definitions apply. 3.1.1 atmosphere 23/50 a controlled atmosphere at a temperature of (23 2)8C and a relative humidity of (50 5) % 3.1.2 hygroscopic range moisture
31、 content in equilibrium with 98 % relative humidity or lower 3.1.3 equivalent time,Dt e d 2 hours, where d is the numerical value of the test specimen thickness in centimetres 3.1.4 limiting value of moisture content change,Dw 1 the change in moisture content during a specified period of equivalent
32、time,Dt e , at the upper limit of the hygroscopic range 3.1.5 conditioning time factor, g the factor by which the equivalent time,Dt e , has to be multiplied to determine the required conditioning period in the hygroscopic range 3.2 Abbreviations EPS expanded polystyrene ICB insulation cork board MW
33、 mineral wool PUR polyurethane foam XPS extruded polystyrene foam 4 Principle The conditioning is carried out using one or two steps, see Figure 1. Step 1 is conditioning the test specimen to a moisture content within the hygroscopic range. This conditioning may take place in an atmosphere 23/50 or
34、in a ventilated oven. The choice of condition depends on the type of material. Alternative I shows drying in atmosphere 23/50 and alternative II drying in a heated oven. Step 2 is conditioning the test specimen to equilibrium with an atmosphere 23/50, after the moisture content has reached the hygro
35、scopic range. 5 Apparatus 5.1 Temperature and humidity controlled chamber, capable of maintaining the atmosphere 23/50. 5.2 Temperature controlled ventilated oven, that takes the air from an environment of 23/50. The oven shall be capable of maintaining a temperature of (40 5)8C or (70 5)8C or (105
36、5)8C as specified in the relevant product standard or any other European technical specification. 5.3 Measuring instruments, capable of measuring the linear dimensions of test specimens in accordance with EN 12085, to an accuracy of 1 %.Page 4 EN 12429:1998 BSI 1998 6 Test specimens 6.1 Dimensions o
37、f test specimens The thickness of the test specimens shall be the original product thickness. The test specimens shall be squarely cut and square, having sides of (200 1) mm. 6.2 Number of test specimens The number of test specimens shall be as specified in the relevant product standard. If the numb
38、er is not specified, then at least three test specimens shall be conditioned. NOTE In the absence of a product standard or any other European technical specification, the number of test specimens may be agreed between parties. 6.3 Preparation of test specimens The test specimens shall be cut so that
39、 they are representative of the full size product. Any surface skins, facings and/or coatings shall be retained. 6.4 Preconditioning of test specimens If the procedure shown in Figure 1a) is used ensure that the test specimens have a moisture content well above the hygroscopic range. If in this case
40、 the hygroscopic sorption curve for the product is not known, it shall be determined in accordance with prEN ISO 12571. NOTE To increase the moisture content to above the hygroscopic range it may be necessary to immerse the test specimens in water, expose them to the exterior climate or expose them
41、to water vapour in accordance with EN 12088: Thermal insulating products for building applications Determination of long-term water absorption by diffusion. 7 Procedure 7.1 General Determine the linear dimensions in accordance with EN 12085 to an accuracy of 1 %. Calculate the volume, V, of each tes
42、t specimen. The conditioning is carried out using either of the alternative procedures shown in Figure 1a) (steps 1 and 2) or the procedure shown in Figure 1b) (step 2 alone). The test specimens shall be installed in the chamber or ventilated oven such that substantially free air circulation occurs
43、around them. In some cases, the moisture content will be within the hygroscopic range before the conditioning starts. In this case step 1 shall be omitted and only step 2 in accordance with Figure 1b) shall be followed. 7.2 Conditioning step 1 Place the test specimens in an atmosphere 23/50, or in a
44、 ventilated oven at an elevated temperature. The temperature shall be as specified in the relevant product standard. NOTE 1 In the absence of a product standard or any other European technical specification the temperature may be agreed between parties. w 0 is the initial moisture content; w 98 is t
45、he moisture content at upper limit of hygroscopic range; w e is the moisture content in equilibrium with atmosphere 23/50. Figure 1 Moisture content versus time during step 1 and step 2Page 5 EN 12429:1998 BSI 1998 At preselected intervals of time, depending on the product tested and the atmosphere
46、used, remove and weigh the test specimens to determine any mass changes. Continue until the change in moisture content is less than the limiting value, i.e. Dw Dw 1 where: Dw is the change in moisture content during a period of d 2 hours (d being the numerical value of the test specimen thickness in
47、 centimetres), in kilograms per cubic metre; Dw 1 is the appropriate limiting value of moisture content change, determined in accordance with annex A, in kilograms per cubic metre. NOTE 2 The limiting value of moisture content change may be determined following the procedures in annex B. A suitable
48、time interval is normally 24 h. Constant mass is considered to have been established when the change in the mass of the test specimen over a 24 h period is less than 0,05 % of the total mass. NOTE 3 For products with a thickness greater than 10 cm, extra drying out time may be required. The acceptab
49、le rate of drying is inversely proportional to the square of the thickness, i.e. a 20 cm product would require a change in mass less than 0,013 % per 24 h. NOTE 4 A temperature as high as possible is desirable because this will minimize the conditioning period, but the temperature should not be so high as to cause changes in the material properties. NOTE 5 The effect of moulded skins should be taken into account by increasing the thickness, d, in the expression “d 2 hours”. The increase should be
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