1、BSI Standards PublicationBS EN ISO 6926:2016Acoustics Requirementsfor the performance andcalibration of referencesound sources used for thedetermination of sound powerlevelsBS EN ISO 6926:2016 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN ISO 6926:2016.It supe
2、rsedes BS EN ISO 6926:2001 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee EH/1/4, Machinery noise.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the nece
3、ssaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2016.Published by BSI Standards Limited 2016ISBN 978 0 580 81380 1ICS 17.140.01Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was
4、published under the authority of theStandards Policy and Strategy Committee on 29 February 2016.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 6926 February 2016 ICS 17.140.01 Supersedes EN ISO 6926:2001English Versi
5、on Acoustics - Requirements for the performance and calibration of reference sound sources used for the determination of sound power levels (ISO 6926:2016) Acoustique - Prescriptions relatives aux performances et ltalonnage des sources sonores de rfrence pour la dtermination des niveaux de puissance
6、 acoustique (ISO 6926:2016) Akustik - Anforderungen an die Eigenschaften und die Kalibrierung von Vergleichsschallquellen fr die Bestimmung von Schallleistungspegeln (ISO 6926:2016) This European Standard was approved by CEN on 26 December 2015. CEN members are bound to comply with the CEN/CENELEC I
7、nternal 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 on application to the CEN-CENELEC Management Centre or to
8、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 CEN-CENELEC Management Centre has the same status as the official
9、 versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Nor
10、way, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey andUnited Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2016 CEN All rights of explo
11、itation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 6926:2016 EBS EN ISO 6926:2016EN ISO 6926:2016 (E) 3 European foreword This document (EN ISO 6926:2016) has been prepared by Technical Committee ISO/TC 43 “Acoustics” in collaboration with Technical Com
12、mittee CEN/TC 211 “Acoustics” the secretariat of which is held by DIN. 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 August 2016, and conflicting national standards shall be withdrawn at the lat
13、est by August 2016. 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 responsible for identifying any or all such patent rights. This document supersedes EN ISO 6926:2001. According to the CEN-CE
14、NELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary,
15、Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 6926:2016 has been approved by CEN as EN ISO 6926:2016 without any modifica
16、tion. BS EN ISO 6926:2016ISO 6926:2016(E)Foreword vIntroduction vi1 Scope . 12 Normative references 23 Terms and definitions . 24 Reference meteorological conditions . 45 Performance requirements . 55.1 General . 55.2 Temporal steadiness (stability) of sound power output . 55.3 Total broadband sound
17、 power level . 55.4 Spectral characteristics 55.5 Directivity 65.6 Recalibration . 66 Instrumentation 76.1 General . 76.2 Microphone in a hemi-anechoic room 76.3 Microphone in a reverberation test room . 76.4 Microphone frequency response correction . 76.5 Verification . 86.6 Microphone calibration
18、check . 87 Installation and operation of the reference sound source during calibration 87.1 General . 87.2 Requirements in hemi-anechoic rooms 97.3 Requirements in reverberation rooms . 98 Calibration procedure in hemi-anechoic rooms . 98.1 Test environment 98.2 Microphone positions . 98.2.1 General
19、 98.2.2 Meridional paths 98.2.3 Spiral path 98.2.4 Fixed point array 98.2.5 Coaxial circular paths 98.3 Measurements 108.3.1 General. 108.3.2 Directivity index 108.3.3 Temporal steadiness 108.4 Calculations . 119 Calibration procedure in reverberation test rooms .129.1 Test environment . 129.2 Micro
20、phone positions 129.3 Measurements 129.3.1 General. 129.3.2 Temporal steadiness 139.4 Calculations . 1310 Alternative calibration procedure at low frequencies .1311 Measurement uncertainty .1311.1 General 1311.2 Typical values of the reproducibility standard deviation .1412 Information to be recorde
21、d 15 ISO 2016 All rights reserved iiiContents PageBS EN ISO 6926:2016ISO 6926:2016(E)13 Information to be reported 15Annex A (informative) Guidance on the determination of C216Annex B (normative) Alternative calibration procedure at low frequencies 18Bibliography .19iv ISO 2016 All rights reservedBS
22、 EN ISO 6926:2016ISO 6926:2016(E)ForewordISO (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 inter
23、ested 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 Electrotechnical
24、 Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO docume
25、nts should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives). Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsibl
26、e for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents). Any trade name used in this document is information given for
27、the convenience of users and does not constitute an endorsement.For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL:
28、Foreword - Supplementary informationThe committee responsible for this document is ISO/TC 43, Acoustics, Subcommittee SC 1, Noise.This third edition cancels and replaces the second edition (ISO 6926:1999), which has been technically revised with the following changes: the clause on measurement uncer
29、tainty has been updated with stricter reference to ISO/IEC Guide 98-3 and moved backwards in the standard to be more in line with ISO 3745; the corrections for meteorological conditions have been brought in line with ISO 3745 and a new Annex A on the acoustic radiation impedance correction has been
30、introduced; an alternative method using sound intensity for low frequency calibration in hemi-anechoic rooms not fully qualified for low frequencies has been introduced in a new Annex B. ISO 2016 All rights reserved vBS EN ISO 6926:2016ISO 6926:2016(E)IntroductionReference sound sources are used ext
31、ensively in “comparison methods” for determining the noise emissions of physically stationary sound sources. A reference sound source, of known sound power output, is used to establish the numerical relationship between the sound power level of a source, in a given location in a given acoustic envir
32、onment and the space- and time-averaged sound pressure level at a set of microphone positions. Once that relationship is established, it is straightforward to measure the average sound pressure level produced by an “unknown source” and to determine the sound power level produced by that source.This
33、International Standard defines the important physical and performance characteristics of reference sound sources and specifies procedures for their calibration, primarily to determine the sound power level of other sound sources.This International Standard supplements a group or family of Internatio
34、nal Standards, the ISO 3740 group, which describes various methods for determining the sound power levels of machines and equipment. This group of International Standards specifies the acoustical requirements for measurements that are appropriate for different test environments.Five International St
35、andards in the ISO 3740 group include procedures in which a reference sound source is used: ISO 3741, ISO 3743-1, ISO 3744, ISO 3746 and ISO 3747. ISO 3740 gives guidelines for the use of all the International Standards in the group.Note that the sound power output of reference sound sources will va
36、ry, in particular at low frequencies, with the distance from the source to nearby reflecting planes. Sound power data of reference sound sources are thus valid only for the position used during the calibration.In addition to being useful for determining sound power levels by the comparison method, r
37、eference sound sources can be used for qualification tests on an acoustic environment and to estimate the influence of an acoustic environment on the sound pressure levels produced by one or more sound sources located in that environment. Examples of International Standards referring to reference so
38、und sources with these applications are ISO/TR 11690-3 and ISO 14257. Requirements other than those of this International Standard can be applicable in these cases.vi ISO 2016 All rights reservedBS EN ISO 6926:2016Acoustics Requirements for the performance and calibration of reference sound sources
39、used for the determination of sound power levels1 ScopeThis International Standard specifies the acoustical performance requirements for reference sound sources: temporal steadiness (stability) of the sound power output; spectral characteristics; directivity.Temporal steadiness is defined in terms o
40、f the standard deviation of repeatability (see 5.2). The spectral characteristics can be verified in either a hemi-anechoic room or a reverberation test room from measurements of the frequency band sound power levels in accordance with this International Standard (see 5.4). The performance requireme
41、nts on directivity index can only be verified in a hemi-anechoic room (see 5.5.)This International Standard also specifies procedures for providing level calibration data and uncertainty on a sound source intended for use as a reference sound source in terms of its sound power level under reference
42、meteorological conditions as defined in Clause 4 in octave and in one-third-octave bands, and with frequency weighting A.This International Standard is titled as a calibration standard even though the method is conducted in a testing laboratory and the level calibration results are not directly trac
43、eable to national standards of measure in a strict metrological sense. Testing laboratories performing this method are not expected to meet all requirements normally associated with a calibration laboratory.NOTE ISO/IEC 1702515specifies different requirements for the competence of testing laboratori
44、es and calibration laboratories respectively. Laboratories testing reference sound sources in accordance with this International Standard would typically comply with the requirements for testing laboratories but not necessarily with those for calibration laboratories.This International Standard spec
45、ifies methods to calibrate reference sound sources not only in a free field over a reflecting plane but also in reverberation test rooms at different distances from the boundary surfaces. For the position of the reference sound source on one reflecting plane, the two different test environments ment
46、ioned above are considered equivalent for frequency bands above or equal to 200 Hz. At 160 Hz and below, some systematic differences can occur (see 11.2). For frequencies below 100 Hz, an alternative calibration method using sound intensity is given.The sound source can either be placed directly on
47、the floor or mounted on a stand to be used at a certain elevation above the floor. According to this International Standard, stand-mounted sources are calibrated in reverberation test rooms. Floor-mounted sources are either calibrated in hemi-anechoic or in reverberation test rooms. For floor-mounte
48、d sources in hemi-anechoic rooms, this International Standard is valid only for sources whose maximum vertical dimension is less than 0,5 m and whose maximum horizontal dimension is less than 0,8 m. According to this International Standard, only floor-mounted reference sound sources can be used when
49、 carrying out measurements on a measurement surface. For reference sound sources to be used or calibrated under reverberant conditions, no such restrictions on maximum dimensions apply.INTERNATIONAL STANDARD ISO 6926:2016(E) ISO 2016 All rights reserved 1BS EN ISO 6926:2016ISO 6926:2016(E)2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the re
