1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN ISO 3741:2010Acoustics Determinationof sound power levels andsound energy levels of noisesources using sound pressure Precision methods forreverberation test rooms (ISO3741
2、:2010)BS EN ISO 3741:2010 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN ISO 3741:2010.It supersedes BS EN ISO 3741:2009 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee EH/1/4, Machinery noise.A list of organizatio
3、ns represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. BSI 2010ISBN 978 0 580 56664 6ICS 17.140.01Compliance with a British Standard cannot c
4、onfer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 October 2010.Amendments issued since publicationDate Text affectedEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 3741 October 2010 ICS 17.140.01
5、Supersedes EN ISO 3741:2009English Version Acoustics - Determination of sound power levels and sound energy levels of noise sources using sound pressure - Precision methods for reverberation test rooms (ISO 3741:2010) Acoustique - Dtermination des niveaux de puissance et des niveaux dnergie acoustiq
6、ues mis par les sources de bruit partir de la pression acoustique - Mthodes de laboratoire en salles dessais rverbrantes (ISO 3741:2010) Akustik - Bestimmung der Schallleistungs- und Schallenergiepegel von Gerusch- quellen aus Schalldruckmessungen - Hallraumverfahren der Genauigkeitsklasse 1 (ISO 37
7、41:2010) This European Standard was approved by CEN on 14 August 2010. 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 bibliograph
8、ical references concerning such national standards may be obtained on application to the CEN 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 translation under the responsibility of a C
9、EN member into its own language and notified to the CEN Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
10、Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marn
11、ix 17, B-1000 Brussels 2010 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 3741:2010: EBS EN ISO 3741:2010EN ISO 3741:2010 (E) 3 Foreword The text of ISO 3741:2010 has been prepared by Technical Committee ISO/TC 43 “Acoustics”
12、 of the International Organization for Standardization (ISO) and has been taken over as EN ISO 3741:2010 by Technical Committee CEN/TC 211 “Acoustics” the secretariat of which is held by DS. This European Standard shall be given the status of a national standard, either by publication of an identica
13、l text or by endorsement, at the latest by April 2011, and conflicting national standards shall be withdrawn at the latest by April 2011. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held respons
14、ible for identifying any or all such patent rights. This document supersedes EN ISO 3741:2009. This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association, and supports essential requirements of EU Directive. For relationship with E
15、U Directive, see informative Annex ZA, which is an integral part of this document. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Repu
16、blic, 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 the United Kingdom. Endorsement notice The text of ISO 3741:2010 has be
17、en approved by CEN as a EN ISO 3741:2010 without any modification. BS EN ISO 3741:2010EN ISO 3741:2010 (E) 4 Annex ZA (informative) Relationship between this European Standard and the Essential Requirements of EU Directive 2006/42/EC This European Standard has been prepared under a mandate given to
18、CEN by the European Commission and the European Free Trade Association to provide one means of conforming to Essential Requirements of the New Approach Directive 2006/42/EC on machinery. Once this standard is cited in the Official Journal of the European Communities under that Directive and has been
19、 implemented as a national standard in at least one Member State, compliance with the normative clauses of this standard confers, within the limits of the scope of this standard, a presumption of conformity with the relevant Essential Requirements of that Directive and associated EFTA regulations. W
20、ARNING Other requirements and other EU Directives may be applicable to the products falling within the scope of this standard. BS EN ISO 3741:2010ISO 3741:2010(E) ISO 2010 All rights reserved iiiContents Page Foreword iv Introduction.v 1 Scope1 2 Normative references2 3 Terms and definitions .2 4 Re
21、ference meteorological conditions .6 5 Reverberation test room.6 6 Instrumentation and measurement equipment 10 7 Definition, location, installation, and operation of noise source under test.10 8 Measurements in the reverberation test room .12 9 Determination of sound power levels and sound energy l
22、evels 19 10 Measurement uncertainty.27 11 Information to be recorded.30 12 Test report31 Annex A (informative) Guidelines for the design of reverberation test rooms 32 Annex B (informative) Guidelines for the design of rotating diffusing vanes 34 Annex C (normative) Reverberation test room qualifica
23、tion procedure for the measurement of broad-band sound .35 Annex D (normative) Reverberation test room qualification procedure for the measurement of discrete-frequency components37 Annex E (informative) Extension of frequency range to frequencies below 100 Hz42 Annex F (normative) Calculation of oc
24、tave band sound power levels and sound energy levels, A-weighted sound power levels and A-weighted sound energy levels from one-third-octave band levels .45 Annex G (informative) Guidelines on the development of information on measurement uncertainty .48 Bibliography60 BS EN ISO 3741:2010ISO 3741:20
25、10(E) iv ISO 2010 All rights reservedForeword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body
26、interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotech
27、nical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by t
28、he technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent right
29、s. ISO shall not be held responsible for identifying any or all such patent rights. ISO 3741 was prepared by Technical Committee ISO/TC 43, Acoustics, Subcommittee SC 1, Noise. This fourth edition cancels and replaces the third edition (ISO 3741:1999), which has been technically revised. It also inc
30、orporates the Technical Corrigendum ISO 3741:1999/Cor.1:2001. BS EN ISO 3741:2010ISO 3741:2010(E) ISO 2010 All rights reserved vIntroduction This International Standard is one of the series ISO 37402to ISO 37478, which specify various methods for determining the sound power levels and sound energy l
31、evels of noise sources including machinery, equipment and their sub-assemblies. The selection of one of the methods from the series for use in a particular application depends on the purpose of the test to determine the sound power level or sound energy level and on the facilities available. General
32、 guidelines to assist in the selection are provided in ISO 37402. ISO 37402to ISO 37478give only general principles regarding the operating and mounting conditions of the machinery or equipment for the purposes of the test. It is important that test codes be established for individual kinds of noise
33、 source, in order to give detailed requirements for mounting, loading, and operating conditions under which the sound power levels or sound energy levels are to be obtained. The methods given in this International Standard require the source under test to be mounted in a reverberation test room havi
34、ng specified acoustical characteristics. The methods are then based on the premise that the sound power or sound energy of the source under test is directly proportional to the mean-square sound pressure averaged in space and time, and otherwise depends only on the acoustical and geometric propertie
35、s of the room and on the physical constants of air. For a source emitting sound in narrow bands of frequency or at discrete frequencies, a precise determination of the radiated sound power level or sound energy level in a reverberation test room requires greater effort than for a source emitting sou
36、nd more evenly over a wide range of frequencies, because: a) the space- and time-averaged sound pressure along a short microphone path, or as determined with an array of a small number of microphones, is not always a good estimate of the space- or time-averaged mean-square pressure throughout the ro
37、om; b) the sound power or sound energy radiated by the source is more strongly influenced by the normal modes of the room and by the position of the source within the room. The increased measurement effort in the case of a source emitting narrow bands of sound or discrete tones consists of either th
38、e optimization and qualification of the test room or the use of a greater number of source locations and microphone positions (or increased path length for a moving microphone). The addition of low-frequency absorbers or the installation of rotating diffusers in the test room can help to reduce the
39、measurement effort. The methods specified in this International Standard permit the determination of the sound power level and the sound energy level in one-third-octave frequency bands, from which octave band data, A-weighted frequency data, and total unweighted sound can be computed. This Internat
40、ional Standard describes methods of accuracy grade 1 (precision grade) as defined in ISO 12001. The resulting sound power levels and sound energy levels include corrections to allow for any differences that might exist between the meteorological conditions under which the tests are conducted and ref
41、erence meteorological conditions. For applications in reverberant environments where reduced accuracy is acceptable, reference can be made to ISO 3743-13, ISO 3743-24or ISO 37478. BS EN ISO 3741:2010BS EN ISO 3741:2010INTERNATIONAL STANDARD ISO 3741:2010(E) ISO 2010 All rights reserved 1Acoustics De
42、termination of sound power levels and sound energy levels of noise sources using sound pressure Precision methods for reverberation test rooms 1 Scope 1.1 General This International Standard specifies methods for determining the sound power level or sound energy level of a noise source from sound pr
43、essure levels measured in a reverberation test room. The sound power level (or, in the case of noise bursts or transient noise emission, the sound energy level) produced by the noise source, in frequency bands of width one-third-octave, is calculated using those measurements, including corrections t
44、o allow for any differences between the meteorological conditions at the time and place of the test and those corresponding to a reference characteristic impedance. Measurement and calculation procedures are given for both a direct method and a comparison method of determining the sound power level
45、and the sound energy level. In general, the frequency range of interest includes the one-third-octave bands with mid-band frequencies from 100 Hz to 10 000 Hz. Guidelines for the application of the specified methods over an extended frequency range in respect to lower frequencies are given in Annex
46、E. This International Standard is not applicable to frequency ranges above the 10 000 Hz one-third-octave band. NOTE For higher frequencies, the methods specified in ISO 9295 can be used. 1.2 Types of noise and noise sources The methods specified in this International Standard are suitable for all t
47、ypes of noise (steady, non-steady, fluctuating, isolated bursts of sound energy, etc.) defined in ISO 12001. The noise source under test can be a device, machine, component or sub-assembly. This International Standard is applicable to noise sources with a volume not greater than 2 % of the volume of
48、 the reverberation test room. For a source with a volume greater than 2 % of the volume of the test room, it is possible that the achievement of results as defined in ISO 12001:1996, accuracy grade 1 (precision grade) is not feasible. NOTE In specific cases, the source volume can be increased to a m
49、aximum of 5 % of the room volume. In such cases, the relevant noise test code indicates the possible consequences on the measurement uncertainty. 1.3 Reverberation test room The test rooms that are applicable for measurements made in accordance with this International Standard are reverberation test rooms meeting specified requirements (see Clause 5). 1.4 Measurement uncertainty Information is given on the uncertainty of the sound power levels and sound energy levels determined in accordance with this International Standard, for me
