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1、| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BRITISH STANDARD BS EN 1822-3:1998 The Eur
2、opean Standard EN 1822-3:1998 has the status of a British Standard ICS 23.120 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW High efficiency air filters (HEPA and ULPA) Part 3: Testing flat sheet filter media Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 09:48:12 GMT
3、+00:00 2006, Uncontrolled Copy, (c) BSI BS EN 1822-3:1998 This British Standard, having been prepared under the direction of the Engineering Sector Committee, was published under the authority of the Standards Committee and comes into effect on 15 December 1998 BSI 1998 ISBN 0 580 29839 6 Amendments
4、 issued since publication Amd. No.DateText affected National foreword This British Standard is the English language version of EN 1822-3:1998. The UK participation in its preparation was entrusted by Technical Committee MCE/21, Filters for gases and liquids, to Subcommittee MCE/21/3, Air filters oth
5、er than for air supply for IC engines and compressors, which has the responsibility to: aid enquirers to understand the text; present to the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international
6、and European developments and promulgate them in the UK. A list of organizations represented on this subcommittee can be obtained 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 th
7、e BSI Standards Catalogue under the section entitled International Standards Correspondence Index, or by using the Find facility 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 respon
8、sible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 14, an inside back cover and a back cover. Licensed Copy: sh
9、effieldun sheffieldun, na, Sun Oct 29 09:48:12 GMT+00:00 2006, Uncontrolled Copy, (c) BSI CEN European Committee for Standardization Comite Europe en de Normalisation Europa isches Komitee fu r Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1998 CEN All rights of exploitation in an
10、y form and by any means reserved worldwide for CEN national Members. Ref. No. EN 1822-3:1998 E EUROPEAN STANDARDEN 1822-3 NORME EUROPE ENNE EUROPA ISCHE NORM May 1998 ICS 23.120 Descriptors: air filters, cleaning equipment for gases, ventilation, air conditioning, tests, effectiveness, aerosol, part
11、icle counters, testing conditions, computation English version High efficiency air filters (HEPA and ULPA) Part 3: Testing flat sheet filter media Filtres a air a tre s haute efficacite et filtres a air a tre s faible pe ne tration (HEPA et ULPA) Partie 3: Essais de medias filtrants plans Schwebstof
12、filter (HEPA and ULPA) Teil 3: Pru fung des planen Filtermediums This European Standard was approved by CEN on 6 March 1998. 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 wi
13、thout any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained 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
14、 made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat 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, Icel
15、and, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 09:48:12 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Page 2 EN 1822-3:1998 BSI 1998 Foreword This European Standard has been prepared b
16、y Technical Committee CEN/TC 195, Air filters for general air cleaning, the Secretariat of which is held by DIN. It deals with the performance testing of high efficiency particulate air filters (HEPA) and ultra low penetration air filters (ULPA). The complete European Standard High efficiency air fi
17、lters (HEPA and ULPA) consists of the following parts: Part 1: Classification, performance testing, marking; Part 2: Aerosol production, measuring equipment, particle counting statistics; Part 3: Testing flat sheet filter media; Part 4: Determining leakage of filter elements (Scan method); Part 5: D
18、etermining the efficiency of filter elements. As decided by CEN/TC 195, this European Standard is based on particle counting methods which actually cover most needs of different applications. The difference between this European Standard and previous national standards lies in the technique used for
19、 the determination of the overall efficiency. Instead of mass relationships, this new technique is based on particle counting at the most penetrating particle size (MPPS; range: 0,15 mm to 0,30 mm). It also allows ultra low penetration air filters to be tested, which is not possible with the previou
20、s test methods because of their inadequate sensitivity. 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 November 1998, and conflicting national standards shall be withdrawn at the latest by Novemb
21、er 1998. According to the CEN/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, No
22、rway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. Contents Page Foreword2 1Scope3 2Normative references3 3Definitions and quantities3 4Description of the test method3 5Sampling of sheet filter media3 6Test apparatus5 6.1Test arrangements for testing with monodisperse test aerosol5 6
23、.2Test arrangements for testing with a polydisperse test aerosol5 6.3Test filter mounting assembly5 6.4Determination of the filter medium face velocity9 7Requirements for the test air9 8Testing procedure9 8.1Preparatory checks9 8.2Procedure10 8.3Reference test method10 9Evaluation10 10Test report10
24、11Maintenance and inspection of the test apparatus11 Annex A (informative) Example of an application with evaluation12 Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 09:48:12 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Page 3 EN 1822-3:1998 BSI 1998 1 Scope This European Standard applies to h
25、igh efficiency particulate air filters and ultra low penetration air filters (HEPA and ULPA) used in the field of ventilation and air conditioning and for technical processes, e.g. for clean room technology or applications in the nuclear and pharmaceutical industry. It establishes a procedure for th
26、e determination of the efficiency on the basis of a particle counting method using a liquid test aerosol, and allows a standardized classification of these filters in terms of their efficiency. This European Standard applies to testing sheet filter media used in high efficiency air filters. The proc
27、edure includes methods, test assemblies and conditions for carrying out the test, and the basis for calculating results. 2 Normative references This European Standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropria
28、te places in the text and the publications are listed hereafter. For dated references, subsequent amendments to, or revisions of, any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references, the latest edition of the publica
29、tion referred to applies. EN 1822-1:1998, High efficiency air filters (HEPA and ULPA) Part 1: Classification, performance testing, marking. EN 1822-2:1998, High efficiency air filters (HEPA and ULPA) Part 2: Aerosol production, measuring equipment, particle counting statistics. 3 Definitions and qua
30、ntities 3.1 Definitions For the purposes of this standard, the definitions according to EN 1822-1 and EN 1822-2 apply. 3.2 Quantities Table 1 contains the quantities (terms and symbols) used in this standard to represent measurement variables and calculated values. The values inserted in the equatio
31、n given for these calculations should be in the units specified. 4 Description of the test method When testing the sheet filter medium, the particle size efficiency is determined using a particle counting method. The testing can use a monodisperse or a polydisperse test aerosol. The methods differ i
32、n terms of both the production of the aerosol and the particle counter used. Furthermore, the measurement of the pressure drop is made at the prescribed filter medium velocity. Specimens of the sheet filter medium are fixed in a test filter assembly and subjected to the test air flow corresponding t
33、o the prescribed filter medium velocity. The test aerosol from the aerosol generator shall be conditioned (e.g. vaporization of a solvent) then neutralized, mixed homogeneously with filtered test air and led to the test filter assembly. In order to determine the efficiency, partial flows of the test
34、 aerosol are sampled upstream and downstream of the filter medium. Using a particle counting instrument, the number concentration of the particles contained is determined for various particle sizes. The results of these measurements are used to draw a graph of efficiency against particle size for th
35、e filter medium, and to determine the particle size for which the efficiency is a minimum. This particle size is known as the most penetrating particle size (MPPS). When measuring the particles on the upstream side of the filter medium it may be necessary to use a dilution system in order to reduce
36、the concentration of particles down to the measuring range of the particle counter used. Additional equipment is required to measure the absolute pressure, temperature and relative humidity of the test aerosol and to measure and control the test volume flow rate. 5 Sampling of sheet filter media The
37、 testing of the sheet filter medium shall be carried out on at least five samples. The samples shall be handled with care; the area to be tested shall be free from all folds, kinks, holes or other irregularities. All samples shall be clearly and permanently marked with the following details: a) the
38、designation of the filter medium; b) the upstream side of the filter medium. Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 09:48:12 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Page 4 EN 1822-3:1998 BSI 1998 Table 1 Quantities TermSymbolUnitEquation for the calculation Measured variables Expo
39、sed areaAcm2 Test volume flow rateV cm3/s Pressure dropDpPa Mean particle diameterdpmm Particle numberN Sampling volume flow rateV s cm3/s Sampling durationts Calculated quantities Filter medium velocityucm/s u = V A Mean pressure differenceDpPa Dp =Dpi 1 n i = 1 n Particle number concentrationcNcm2
40、3 cN= N V S3 t Penetration for particles in size range iPi 1) 2) Pi= cN,d,i cN,u,i Mean penetrationP 1) P =Pi 1 n i = 1 n Mean efficiencyE 1) E = 1 2 P Number of particles for the upper or lower limit of the 95 % level of confidence N95%See clause 7 of EN 1822-2:1998 Penetration as upper limit value
41、 for the 95 % level of confidence P95%,i 1) 2) P95%,i= cN,d,95%,i cN,u,95%,i Mean penetration as upper limit value for the 95 % level of confidence P95% 1) P95%=P95%,i 1 n i = 1 n Mean efficiency as lower limit value for the 95 % level of confidence E95% 1) E95%=1 2 P95% 1) These quantities are usua
42、lly given as a percentage. 2) The index u refers to upstream particle counts, and the index d refers to downstream particle counts. Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 09:48:12 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Page 5 EN 1822-3:1998 BSI 1998 1) Actually, the adjustment gi
43、ves the mode of number distribution. This can be taken as equal to the median value with sufficient accuracy. 6 Test apparatus The test apparatus to be used and the arrangement of the components and measuring equipment are shown in Figure 1 of EN 1822-1:1998. The basic details for the aerosol genera
44、tion and the aerosol neutralization, together with the details of suitable types of apparatus are contained in EN 1822-2. 6.1 Test arrangements for testing with monodisperse test aerosol When testing sheet filter media with a monodisperse test aerosol, the particle number concentration is determined
45、 using a total count method with a condensation nucleus counter. The arrangement of the test apparatus is shown in Figure 1. The monodisperse test aerosol is created in a number of steps. Firstly a polydisperse primary aerosol is produced using a jet nebulizer with, for example, a DEHS/iso-propanol
46、solution. The particles are reduced to a convenient size for the following process by evaporation of the solvent. The aerosol is then neutralized and passed to a differential mobility analyser. The quasi-monodisperse test aerosol available at the output of the differential mobility analyser is once
47、again neutralized, and then mixed homogeneously with filtered test air in order to achieve at the test volume flow rate required for the filter medium velocity. The mean particle diameter of the number distribution is varied by adjusting the voltage between the electrodes of the differential mobilit
48、y analyser1). In order to achieve a sufficiently high particle number concentration over the entire test range from 0,04 mm to 0,8 mm, it may prove necessary to use several jet nebulizers with differing concentrations of the aerosol substances in the solvent. Numerical concentrations which are too h
49、igh can be adjusted by diluting the test aerosol before the test filter mounting assembly. The number concentration in the test aerosol shall be selected so that no dilution is necessary for the measurements made downstream from the filter. A pump positioned downstream draws the test aerosol through the test filter mounting assembly. This ensures that the differential mobility analyser can always operate under nearly the same conditions, independent of the pressure drop across the tested filter medium. In c
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