1、BSI Standards PublicationBS EN ISO 9295:2015Acoustics Determination of high-frequency sound power levels emitted by machinery and equipmentBS EN ISO 9295:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN ISO 9295:2015. It supersedes BS 7135-2:1989 which is wi
2、thdrawn.The UK participation in its preparation was entrusted to Technical Committee EH/1/4, Machinery noise.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. User
3、s are responsible for its correct application. The British Standards Institution 2015.Published by BSI Standards Limited 2015ISBN 978 0 580 79208 3 ICS 17.140.20; 35.180; 35.260 Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was published under
4、 the authority of the Standards Policy and Strategy Committee on 30 June 2015.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 9295 May 2015 ICS 17.140.20; 35.020 Supersedes EN 29295:1991English Version Acoustics - Det
5、ermination of high-frequency sound power levels emitted by machinery and equipment (ISO 9295:2015) Acoustique - Dtermination des niveaux de puissance acoustique haute frquence mis par les machines et quipements (ISO 9295:2015) Akustik - Bestimmung der hochfrequenten Schallleistungspegel von Maschine
6、n und Gerten (ISO 9295:2015) This European Standard was approved by CEN on 21 February 2015. 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
7、 lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC 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 u
8、nder 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 versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Forme
9、r Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT E
10、UROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2015 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 9295:2015 EBS EN ISO 9295:2015EN ISO 9295:2015 (E) 3 F
11、oreword This document (EN ISO 9295:2015) has been prepared by Technical Committee ISO/TC 43 “Acoustics” incollaboration with Technical Committee 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 publicat
12、ion of an identicaltext or by endorsement, at the latest by November 2015, and conflicting national standards shall be withdrawnat the latest by November 2015. Attention is drawn to the possibility that some of the elements of this document may be the subject of patentrights. CEN and/or CENELEC shal
13、l not be held responsible for identifying any or all such patent rights. This document supersedes EN 29295:1991. According to the CEN-CENELEC Internal Regulations, the national standards organizations of the followingcountries are bound to implement this European Standard: Austria, Belgium, Bulgaria
14、, Croatia, Cyprus, CzechRepublic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece,Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey an
15、d the United Kingdom. Endorsement notice The text of ISO 9295:2015 has been approved by CEN as EN ISO 9295:2015 without any modification. BS EN ISO 9295:2015ISO 9295:2015(E)Foreword vIntroduction vi1 Scope . 12 Normative references 13 Terms and definitions . 14 Conformity requirements . 15 Requireme
16、nts for measurements in a reverberation test room . 15.1 General . 15.2 Meteorological conditions . 25.3 Instrumentation . 25.4 Installation and orientation of microphone 25.5 Installation and orientation of equipment 35.6 Calibration of measurement system . 35.7 Measurement of sound pressure level
17、36 Method using measured reverberation time 46.1 General . 46.2 Measurement of reverberation time 56.3 Calculation of room absorption 56.4 Installation of microphone and equipment . 56.5 Measurement of sound pressure level 56.6 Calculation of sound power level 67 Method using calculated air absorpti
18、on 67.1 General . 67.2 Calculation of room constant 67.3 Installation of microphone and equipment . 67.4 Measurement of sound pressure level 67.5 Calculation of sound power level 78 Method using a reference sound source 88.1 Reference sound source 88.2 Installation of microphone and equipment . 88.3
19、 Installation of reference sound source . 98.4 Measurement of sound pressure level 98.5 Calculation of sound power level 98.5.1 Equipment emitting broad-band noise 98.5.2 Equipment emitting discrete tone(s) 109 Method using a free field over a reflecting plane 109.1 General 109.2 Meteorological cond
20、itions 109.3 Instrumentation 119.4 Installation and orientation of microphone . 119.5 Installation of equipment . 119.6 Calibration of measurement system 119.7 Measurement of sound pressure level . 129.8 Calculation of surface sound pressure level and sound power level .1210 Calculation of sound pow
21、er level under reference meteorological conditions .1310.1 Reverberation rooms 1310.2 Hemi-anechoic rooms 1311 Measurement uncertainty .1312 Information to be recorded 13 ISO 2015 All rights reserved iiiContents PageBS EN ISO 9295:2015ISO 9295:2015(E)12.1 General 1312.2 Equipment under test 1312.3 A
22、coustic environment 1412.4 Instrumentation 1412.5 Acoustical data . 1413 Information to be reported 14Annex A (normative) Calculation of air absorption coefficient .16Bibliography .18iv ISO 2015 All rights reservedBS EN ISO 9295:2015ISO 9295:2015(E)ForewordISO (the International Organization for Sta
23、ndardization) 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 interested in a subject for which a technical committee has been established has the righ
24、t 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 Commission (IEC) on all matters of electrotechnical standardization.The procedures
25、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 documents should be noted. This document was drafted in accordance with the editorial rule
26、s 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 responsible for identifying any or all such patent rights. Details of any patent rights identif
27、ied 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 the convenience of users and does not constitute an endorsement.For an explanation on
28、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: Foreword Supplementary information .The committee responsible for this document is IS
29、O/TC 43, Acoustics, Subcommittee SC 1, Noise.This second edition cancels and replaces the first edition (ISO 9295:1988), which has been technically revised. ISO 2015 All rights reserved vBS EN ISO 9295:2015ISO 9295:2015(E)IntroductionSome machinery and equipment emit high-frequency noise which might
30、 be broad-band noise (e.g. paper noise of high-speed printing) or narrow-band noise and discrete tones (e.g. noise of switching power supplies and video display units or medical devices).This International Standard specifies methods for the determination of the sound power levels in the frequency ra
31、nge covered by the octave band centred at 16 kHz. The measured levels are not frequency-weighted. The principal objective of this International Standard is to prescribe methods for determining the sound power levels and frequencies of tones which are contained within the 16 kHz octave band.vi ISO 20
32、15 All rights reservedBS EN ISO 9295:2015Acoustics Determination of high-frequency sound power levels emitted by machinery and equipment1 ScopeThis International Standard specifies four methods for the determination of the sound power levels of high-frequency noise emitted by machinery and equipment
33、 in the frequency range covered by the octave band centred at 16 kHz, which includes frequencies between 11,2 kHz and 22,4 kHz. They are complementary to the methods described in ISO 3741 and ISO 3744. The first three methods are based on the reverberation test room technique. The fourth method make
34、s use of a free field over a reflecting plane.The test conditions which prescribe the installation and operation of the equipment are those specified in ISO 3741 or ISO 3744 as applicable.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document
35、and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 3741, Acoustics Determination of sound power levels and sound energy levels of noise sources u
36、sing sound pressure Precision methods for reverberation test roomsISO 3744, Acoustics Determination of sound power levels and sound energy levels of noise sources using sound pressure Engineering methods for an essentially free field over a reflecting planeISO 6926, Acoustics Requirements for the pe
37、rformance and calibration of reference sound sources used for the determination of sound power levelsISO 9613-1, Acoustics Attenuation of sound during propagation outdoors Part 1: Calculation of the absorption of sound by the atmosphere3 Terms and definitionsFor the purpose of this document, the ter
38、ms and definitions given in ISO 3741 and ISO 3744 apply.4 Conformity requirementsA method for the measurement of high-frequency noise is in conformance with this International Standard if it satisfies all the mandatory requirements of one of the four methods described herein specified in Clauses 6 t
39、o 9, and if the information recorded and reported is as specified in Clauses 12 and 13, respectively.5 Requirements for measurements in a reverberation test room5.1 GeneralThis International Standard describes three methods using the reverberation test room technique of ISO 3741. The first and the s
40、econd methods are usually called “direct methods” because they use directly measured or calculated reverberation times. The third method is a so-called “comparison method”. A calibrated reference sound source is used from which the sound power levels of the equipment are determined by comparison.INT
41、ERNATIONAL STANDARD ISO 9295:2015(E) ISO 2015 All rights reserved 1BS EN ISO 9295:2015ISO 9295:2015(E)All three methods require a determination of the mean time-averaged sound pressure level in the reverberant field.As instrumentation and basic measurement techniques are the same for all three metho
42、ds, they are summarized in 5.3 to 5.7. Additional requirements specific to each method are given separately. For additional requirements on instrumentation, see ISO 3741.5.2 Meteorological conditionsThe air absorption in the reverberation test room varies with temperature and humidity, particularly
43、at frequencies above 1 000 Hz. The temperature, , in degrees Celsius (C) and the relative humidity, hr, expressed as a percentage, shall be controlled during the sound pressure level measurements.The product, hr ( + 5 C), shall not vary by more than 10 % during the measurements.For equipment whose n
44、oise emissions intentionally vary with ambient temperature (e.g. by varying the speeds of air moving devices), the room temperature during the test measurement shall be 23 C 2 C or, if the room temperature is outside these limits, the fan shall be adjusted to the speed for an ambient temperature of
45、23 C 2 C.The following conditions are recommended: Static pressure: 86 kPa to 106 kPa; Temperature: 15 C to 30 C; Relative humidity: 40 % to 70 %.NOTE As indicated in Tables 1 and 2 for the temperature range of 18 C to 27 C, higher temperatures and higher humidity will tend to minimize the effects o
46、f atmospheric absorption.5.3 InstrumentationThe sound measuring system, including the microphone, should have a flat frequency response for random incident sound in the 16 kHz octave band. The microphone response shall be corrected to give a flat frequency response within in the 16 kHz octave band.
47、The tolerances after correction shall be within 1,0 dB in the frequency range of 11,2 kHz to 22,4 kHz.NOTE 1 To meet this requirement, a microphone with a diameter of 13,2 mm or less is usually required.When the noise of the equipment under test is broad-band in character without any significant dis
48、crete tone, an analyser with a bandwidth of one-third-octave or less shall be used. When the noise of the equipment under test contains discrete tone(s), a narrow-band analyser, which provides bandwidths of less than one-third-octave in width, shall be used to determine the frequency of the tone(s).
49、NOTE 2 For narrow-band analysis, an analyser with a bandwidth equal to, or less than, one twelfth octave is appropriate. Digital analysers using fast Fourier transform (FFT) or equivalent techniques can be useful, particularly when the analyser combines narrow-band analysis and averaging.5.4 Installation and orientation of microphoneThe microphone shall be mounted at the end of a rotating boom traversing a circle with a diameter of at least 2 m. In order to reduce the influence of the direct field on the measured sou
