1、BS EN 15803:2009ICS 97.195NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBRITISH STANDARDConservation of cultural property Test methods Determination of water vapour permeability (nullp)This British Standardwas published under theauthority of the StandardsPolicy and StrategyCo
2、mmittee on 28 February2010. BSI 2010ISBN 978 0 580 61877 2Amendments/corrigenda issued since publicationDate CommentsBS EN 15803:2009National forewordThis British Standard is the UK implementation of EN 15803:2009.The UK participation in its preparation was entrusted to TechnicalCommittee B/560, Con
3、servation of tangible cultural heritage.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisionsof a contract. Users are responsible for its correct application.Compliance with a British
4、 Standard cannot confer immunityfrom legal obligations.BS EN 15803:2009EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 15803 December 2009 ICS 97.195 English Version Conservation of cultural property - Test methods - Determination of water vapour permeability (p) Conservation des biens culturel
5、s - Mthodes dessai - Dtermination de la permabilit la vapeur deau (p) Erhaltung des kulturellen Erbes - Prfverfahren - Bestimmung des Wasserdampfleitkoeffizienten (p) This European Standard was approved by CEN on 7 November 2009. CEN members are bound to comply with the CEN/CENELEC Internal Regulati
6、ons 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 on application to the CEN Management Centre or to any CEN member. This Eur
7、opean 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 CEN Management Centre has the same status as the official versions. CEN members are the n
8、ational standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland a
9、nd United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2009 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 15803
10、:2009: EBS EN 15803:2009EN 15803:2009 (E) 2 Contents Page Foreword 3Introduction .41 Scope 52 Normative references 53 Terms and definitions .54 Principle 65 Symbols and abbreviations 66 Test equipment 77 Preparation of test specimens . 107.1 Number and dimensions of test specimens 108 Test procedure
11、 108.1 General . 108.2 Test environmental conditions 108.3 Procedure 119 Expression of results . 119.1 Cumulative mass change and density of water vapour flow rate 119.2 Water vapour permeance . 129.3 Water vapour permeability . 129.4 Water vapour diffusion resistance coefficient . 129.5 Water vapou
12、r diffusion-equivalent air layer thickness . 1210 Test report . 12Bibliography . 14BS EN 15803:2009EN 15803:2009 (E) 3 Foreword This document (EN 15803:2009) has been prepared by Technical Committee CEN/TC 346 “Conservation of cultural property”, the secretariat of which is held by UNI. This Europea
13、n Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by June 2010 and conflicting national standards shall be withdrawn at the latest by June 2010. Attention is drawn to the possibility that some of the elements of t
14、his document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European St
15、andard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. B
16、S EN 15803:2009EN 15803:2009 (E) 4 Introduction This test method can be applied if it does not change the value of the cultural property and follows relevant ethical codes of conservation practice. BS EN 15803:2009EN 15803:2009 (E) 5 1 Scope This European Standard specifies a method for determining
17、the water vapour permeability (WVP) of porous inorganic materials used for and constituting cultural property. The method may be applied to porous inorganic materials either untreated or subjected to any treatment or ageing. 2 Normative references The following referenced documents are indispensable
18、 for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. prEN 15898:2009, Conservation of cultural property Main general terms and definitions concerning cons
19、ervation of cultural property 3 Terms and definitions For the purposes of this document, the terms and definitions given in prEN 15898:2009 and the following apply. 3.1 porous inorganic materials materials including natural stones, e.g. sandstone, limestone, marble, as well as artificial materials,
20、such as mortar, plaster, brick and others 3.2 water vapour flow rate G mass of water vapour transferred through the specimen per time 3.3 density of water vapour flow rate vapour transmission rate g mass of water vapour transferred through the specimen per time and per unit area 3.4 water vapour per
21、meance Wpvalue of the mass of water vapour diffused through a specimen, induced by a partial vapour pressure gradient through the specimen, per unit area, time and partial vapour pressure difference 3.5 water vapour permeability pproduct of the water vapour permeance and the thickness of a homogeneo
22、us specimen 3.6 water vapour permeability of air a water vapour permeability of air ais defined by the Schirmer equation: a= 0,000 023 1 (po/(p R T) (T/273 K)1,81kg/(msPa) (1) BS EN 15803:2009EN 15803:2009 (E) 6 where pois the standard barometric pressure (= 1 013,25 hPa); p is the barometric pressu
23、re (hPa); T is the temperature (K); R is the gas constant for water vapour (= 462 Nm/(kgK) 3.7 water vapour diffusion resistance coefficient water vapour permeability of air divided by that of the material concerned 3.8 water vapour diffusion-equivalent air layer thickness sdvalue of a specimen whic
24、h indicates the thickness of a motionless air layer that has the same water vapour resistance as the specimen of thickness D. The sdvalue can be obtained in two ways: i) by multiplication of the -value with the thickness D of the specimen; ii) from the water vapour permeability of air adivided by th
25、e water vapour permeance of the specimen Wp 4 Principle Determination of the water vapour flow through the specimen subjected to different partial water vapour pressures. 5 Symbols and abbreviations For the purposes of this document, the following symbols and abbreviations apply: m mass of specimen
26、and cup assembly, in kg D mean thickness of specimen, in m A test surface area, in m t time, in s G water vapour flow rate through specimen, in kg/s g density of water vapour flow rate, in kg/(ms) pvwater vapour pressure difference across the specimen, in Pa Wpwater vapour permeance with respect to
27、partial vapour pressure, in kg/(msPa) pwater vapour permeability with respect to partial vapour pressure, in kg/(msPa) awater vapour permeability of air, in kg/(msPa) BS EN 15803:2009EN 15803:2009 (E) 7 water vapour diffusion resistance coefficient (-) sdwater vapour diffusion-equivalent air layer t
28、hickness, in m 6 Test equipment 6.1 Test set-ups: two types of cup systems are possible as presented in Figure 1 and Figure 2. The cups weight should be compatible with the measurement method which needs the use of an analytical balance. Test cups shall be resistant to corrosion from the desiccant o
29、r salt solutions. Typically cups are made of glass, metal or PVC. For certain cups and sealing methods, a template, with shape and size corresponding to that of the test cup, is used when applying the sealant to give a sharply defined, reproducible test area. The template shall have an area of at le
30、ast 90 % of the specimen to limit non-linear vapour flow. The sealant, which is impermeable to water vapour, should neither undergo changes during the test nor bring about changes to the test surface of the specimen. NOTE Circular cups can be easier to seal. Transparent cups enable observing the tes
31、t in progress; thus, the saturated state of the salt solutions can be monitored. Examples of suitable sealants: a mixture of 90 % microcrystalline wax and 10 % plasticizer; a mixture of 60 % microcrystalline wax and 40 % refined crystalline paraffin. BS EN 15803:2009EN 15803:2009 (E) 8 Key 1 vessel
32、with sorbent 2 specimen 3 sealing 4 adhesive tape 5 stop ring Figure 1 Examples of schematic cup system type 1 BS EN 15803:2009EN 15803:2009 (E) 9 Key 1 joint rubber 2 aluminium disc 3 higher trimming 4 specimen 5 lower trimming 6 PVC cup Figure 2 Example of a schematic cup system type 2 6.2 An anal
33、ytical balance with an accuracy of 0,001 g, capable of weighing the test assembly. In the case of material with a porosity 1 %, an analytical balance with higher resolution (0,000 1 g) is recommended. 6.3 A test chamber to achieve controlled experimental conditions of temperature and relative humidi
34、ty. The temperature is set at (23 1) C. For the relative humidity, a maximum variation of 3 % of the set point 50 % is allowed. The air velocity above the specimens shall not exceed 0,3 m/s and shall not fall short of 0,02 m/s. 6.4 Suitable sensors to continuously record the temperature, relative hu
35、midity and, if necessary, the barometric pressure in the test chamber. The sensors shall be calibrated at regular intervals. 6.5 A barometer with an accuracy of 0,1 kPa. 6.6 A linear measuring device (calliper) with an accuracy of 0,1 mm. BS EN 15803:2009EN 15803:2009 (E) 10 7 Preparation of test sp
36、ecimens 7.1 Number and dimensions of test specimens The number of specimens is related to the heterogeneity of the material. At least 3 specimens are recommended for the test. In case of anisotropy, each series shall be tested according to the same orientation. The specimens shall be prepared in a w
37、ay that the parallel test faces are perpendicular to the direction of water vapour flow. Specimens shall be cut as to correspond with the dimensions of the chosen test assembly (see 6.1). The thickness of the specimens will influence the time to reach the equilibrium as well as the precision of the
38、test method. For compact and homogeneous materials it is recommended to use specimens of a thickness D of maximum 20 mm. In the case of heterogeneous materials, such as mortars containing coarse aggregates, the thickness of the specimens shall be at least two times the largest particle size. The dia
39、meter of the test area (A) shall be at least two times the specimens thickness. In the case of heterogeneous materials, such as mortars containing coarse aggregates, the diameter of the test area shall be at least five times the largest grain size. The test area shall be the arithmetic mean between
40、the free lower tested surface and its opposite face area. The test area of the two opposite faces shall not deviate more than 10 %. The number and dimension of the specimens can be different in cases when there could be difficulties in sampling the required amount of material. 7.2 Pre-conditioning o
41、f test specimens Before testing, the specimen shall be stored at (23 1) C and (50 3) % relative humidity for a period long enough for their weight to stabilize with the test climatic conditions. Constant mass is reached when the difference between two successive weighings at an interval of 24 h is n
42、ot greater than 0,1 % of the mass of the specimen. 8 Test procedure 8.1 General The test specimen shall be mounted in the cup with the test face up and sealed to the open side of a test cup containing either a desiccant (dry cup) or an aqueous saturated salt solution (wet cup). The assembly shall th
43、en be placed in the pre-conditioned test chamber. Because of the different partial water vapour pressure between the inside of the test cup and the test chamber, a water vapour flow through the specimen occurs. In order to measure the water vapour permeability in the steady state, the mass of the cu
44、p system is periodically determined by means of weighing. 8.2 Test environmental conditions The procedure is based on the “dry cup” or the “wet cup” system and can use the cups shown in Figure 1 or Figure 2. One of the cup systems presented in Table 1 shall be selected. Only results obtained from te
45、sts using the same cup system can be compared. BS EN 15803:2009EN 15803:2009 (E) 11 Table 1 Test conditions Cup system Boundary condition for temperature (internal and external) (C) Internal relative humidity RH (%) External relative humidity RH (%) Dry cup 23 1 0 to 3 50 3 Wet cup 23 1 93 3 50 3 Dr
46、y cup tests give information about the performance of materials at low humidities when moisture transfer is dominated by vapour diffusion. Wet cup tests give guidance about the performance of materials under high humidity conditions. At high humidity (93 %), the specimen pores start to fill with wat
47、er which increases transport of liquid water and reduces vapour transport. Consequently, test results obtained under these conditions give some information about liquid water transport properties in porous materials. Adequate saturated salt solutions or gels are examples of suitable sorbents. The fo
48、llowing desiccants and saturated aqueous solutions produce the specified relative air humidity at 23 C: Silica gel: 0 to 3 %; Magnesium nitrate Mg(NO3)2: 53 %; Calcium nitrate Ca(NO3)2: 50 %; Ammonium dihydrogen phosphate NH4H2PO4: 93 %; Potassium nitrate KNO3: 93 %. NOTE Ammonium phosphate is not c
49、ompatible with metal. 8.3 Procedure Prepare the test specimens as specified in 6.1 for the selected test assembly. The thickness of the specimens is measured with an accuracy of 0,1 mm at four positions equally spaced around the circumference. Calculate the mean thickness D. Place the desiccant or aqueous solution with minimum of 15 mm in the bottom of each cup so that the air space between the desiccant or
