ASA S12 51-2012 AMERICAN NATIONAL STANDARD Acoustics C Determination of sound power levels and sound energy levels of noise sources using sound pressure C Precision methods for rev.pdf

1、 ANSI/ASA S12.51-2012 / ISO 3741:2010 (a revision of ANSI S12.51-2002 / ISO 3741:1999) AMERICAN NATIONAL STANDARD Acoustics Determination of sound power levels and sound energy levels of noise sources using sound pressure Precision methods for reverberation test rooms (a Nationally Adopted Internati

2、onal Standard) e Accredited Standards Committee S12, Noise Standards Secretariat Acoustical Society of America 35 Pinelawn Road, Suite 114 E Melville, NY 11747-3177ANSI/ASAS12.51-2012/ ISO 3741:2010The American National Standards Institute, Inc. (ANSI) is the national coordinator of voluntary standa

3、rds development and the clearinghouse in the U.S.A. for information on national and international standards. The Acoustical Society of America (ASA) is an organization of scientists and engineers formed in 1929 to increase and diffuse the knowledge of acoustics and to promote its practical applicati

4、ons. ANSI/ASA S12.51-2012 / ISO 3741:2010 AMERICAN NATIONAL STANDARD Acoustics Determination of sound power levels and sound energy levels of noise sources using sound pressure Precision methods for reverberation test rooms (a nationally adopted international standard) Secretariat: Acoustical Societ

5、y of America Approved on February 23, 2012 by: American National Standards Institute, Inc. Abstract This American National Standard specifies methods for determining the sound power level or sound energy level of a noise source from sound pressure levels measured in a reverberation test room. The so

6、und 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 to allow for any differences between the meteorological cond

7、itions 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 and the sound energy level. AMERICAN NATIONAL STANDARDS ON

8、ACOUSTICS The Acoustical Society of America (ASA) provides the Secretariat for Accredited Standards Committees S1 on Acoustics, S2 on Mechanical Vibration and Shock, S3 on Bioacoustics, S3/SC 1 on Animal Bioacoustics, and S12 on Noise. These committees have wide representation from the technical com

9、munity (manufacturers, consumers, trade associations, organizations with a general interest, and government representatives). The standards are published by the Acoustical Society of America as American National Standards after approval by their respective Standards Committees and the American Natio

10、nal Standards Institute (ANSI). These standards are developed and published as a public service to provide standards useful to the public, industry, and consumers, and to Federal, State, and local governments. Each of the Accredited Standards Committees (operating in accordance with procedures appro

11、ved by ANSI) is responsible for developing, voting upon, and maintaining or revising its own Standards. The ASA Standards Secretariat administers Committee organization and activity and provides liaison between the Accredited Standards Committees and ANSI. After the Standards have been produced and

12、adopted by the Accredited Standards Committees, and approved as American National Standards by ANSI, the ASA Standards Secretariat arranges for their publication and distribution. An American National Standard implies a consensus of those substantially concerned with its scope and provisions. Consen

13、sus is established when, in the judgment of the ANSI Board of Standards Review, substantial agreement has been reached by directly and materially affected interests. Substantial agreement means much more than a simple majority, but not necessarily unanimity. Consensus requires that all views and obj

14、ections be considered and that a concerted effort be made towards their resolution. The use of an American National Standard is completely voluntary. Their existence does not in any respect preclude anyone, whether he or she has approved the Standards or not, from manufacturing, marketing, purchasin

15、g, or using products, processes, or procedures not conforming to the Standards. NOTICE: This American National Standard may be revised or withdrawn at any time. The procedures of the American National Standards Institute require that action be taken periodically to reaffirm, revise, or withdraw this

16、 Standard. Acoustical Society of America ASA Secretariat 35 Pinelawn Road, Suite 114E Melville, New York 11747-3177 Telephone: 1 (631) 390-0215 Fax: 1 (631) 390-0217 E-mail: asastdsaip.org 2012 by Acoustical Society of America. This standard may not be reproduced in whole or in part in any form for

17、sale, promotion, or any commercial purpose, or any purpose not falling within the provisions of the U.S. Copyright Act of 1976, without prior written permission of the publisher. For permission, address a request to the Standards Secretariat of the Acoustical Society of America. ANSI/ASA S12.51-2012

18、 / ISO 3741:2010 2012 Acoustical Society of AmericaAll rights reserved iiiContents 1 Scope 1 1.1 General . 1 1.2 Types of noise and noise sources 1 1.3 Reverberation test room 1 1.4 Measurement uncertainty 2 2 Normative references 2 3 Terms and definitions 2 4 Reference meteorological conditions 7 5

19、 Reverberation test room 7 5.1 General . 7 5.2 Volume and shape of test room 7 5.3 Sound absorption of test room 7 5.4 Criteria for background noise 8 5.5 Atmospheric temperature, humidity and pressure 10 6 Instrumentation and measurement equipment . 11 6.1 General . 11 6.2 Calibration . 11 7 Defini

20、tion, location, installation, and operation of noise source under test . 12 7.1 General . 12 7.2 Auxiliary equipment . 12 7.3 Noise source location 12 7.4 Installation and mounting conditions . 12 7.5 Operation of source during test . 13 8 Measurements in the reverberation test room 14 8.1 General .

21、 14 8.2 Initial location of the noise source under test 14 8.3 Microphone positions 14 8.4 Measurement of sound pressure levels 16 8.5 Measurement of single event time-integrated sound pressure levels 19 8.6 Measurement of sound pressure levels from the reference sound source for the comparison meth

22、od 20 8.7 Measurement of reverberation time 21 8.8 Measurement of meteorological conditions 21 9 Determination of sound power levels and sound energy levels 21 9.1 Determination of sound power levels 21 9.2 Determination of sound energy levels . 26 9.3 A-weighted sound power level and sound energy l

23、evel 30 10 Measurement uncertainty 30 10.1 Methodology 30 10.2 Determination of omc31 10.3 Determination of R032 10.4 Typical upper bound values of R033 10.5 Total standard deviation totand expanded measurement uncertainty, U . 34 11 Information to be recorded 34 11.1 General . 34 11.2 Noise source

24、under test 34 ANSI/ASA S12.51-2012 / ISO 3741:2010 iv 2012 Acoustical Society of AmericaAll rights reserved11.3 Test environment 35 11.4 Instrumentation . 35 11.5 Acoustical data 35 12 Test report . 36 Annex A (informative) Guidelines for the design of reverberation test rooms 37 A.1 General . 37 A.

25、2 Volume of reverberation test room 37 A.3 Shape of reverberation test room . 37 A.4 Absorption of reverberation test room . 38 Annex B (informative) Guidelines for the design of rotating diffusing vanes 39 Annex C (normative) Reverberation test room qualification procedure for the measurement of br

26、oad-band sound . 40 C.1 Introduction . 40 C.2 Instrumentation and equipment 40 C.3 Test procedure 40 C.4 Calculation 41 C.5 Qualification 41 Annex D (normative) Reverberation test room qualification procedure for the measurement of discrete-frequency components 42 D.1 Introduction . 42 D.2 General .

27、 43 D.3 Instrumentation and measurement equipment . 43 D.4 Loudspeaker test . 43 D.5 Room test 44 D.6 Computational procedure 44 D.7 Qualification 45 D.8 Multiple source locations . 45 Annex E (informative) Extension of frequency range to frequencies below 100 Hz . 47 E.1 Additional frequency range

28、. 47 E.2 Supplement to Table 6 47 E.3 Supplement to Table 1 (Minimum volume of the reverberation test room as a function of the lowest frequency band of interest) 47 E.4 Supplement to Table 4 (Minimum number of microphone positions for the measurement of sound pressure level) and Table 5 (Minimum nu

29、mber of source locations for the measurement of sound pressure level) . 47 E.5 Supplement to Table C.1 48 E.6 Supplement to Tables D.1 and D.2 . 48 Annex F (normative) Calculation of octave band sound power levels and sound energy levels, A-weighted sound power levels and A-weighted sound energy lev

30、els from one-third-octave band levels 50 F.1 Sound power levels . 50 F.2 Sound energy levels 51 F.3 Values of k and Ckfor use in calculations . 52 Annex G (informative) Guidelines on the development of information on measurement uncertainty 54 G.1 General . 54 G.2 Considerations on the total standar

31、d deviation tot. 54 G.3 Considerations on omc. 55 G.4 Considerations on R0. 56 G.5 Combined standard uncertainty 67 G.6 Measurement uncertainty based on reproducibility data 67 ANSI/ASA S12.51-2012 / ISO 3741:2010 2012 Acoustical Society of AmericaAll rights reserved vTables Table 2 Absolute maximum

32、 background noise levels in test room . 10 Table 3 Allowable limits in the variation of atmospheric temperature and relative humidity during measurements in the reverberation test room . 11 Table 4 Minimum number of microphone positions for the measurement of sound pressure levels 18 Table 5 Minimum

33、 number of source locations and value, KS, for the measurement of sound pressure levels 19 Table 6 Typical upper bound values of the standard deviation of reproducibility of the method, R0, for A-weighted sound power levels and sound energy levels determined in accordance with this American National

34、 Standard 34 Table A.1 Recommended room dimension ratios for right cuboid rooms 38 Table C.1 Maximum allowable standard deviation of Lpi. 41 Table D.1 Maximum allowable sample standard deviations, sf42 Table D.2 Test frequencies for alternative qualification of reverberation test room for measuring

35、sound power levels and sound energy levels of noise sources emitting significant discrete-frequency components . 46 Table E.1 Standard deviations of reproducibility and typical total standard deviations of sound power levels and sound energy levels below 100 Hz . 47 Table E.2 Maximum allowable stand

36、ard deviation of Lpi. 48 Table E.3 Maximum allowable sample standard deviations, sf. 48 Table E.4 Test frequencies for alternative qualification of reverberation test room for measuring sound power levels and sound energy levels of noise sources emitting significant discrete-frequency components . 4

37、9 Table F.1 Values of k and Ckfor mid-band frequencies of one-third-octave bands . 53 Table G.1 Examples of calculated total standard deviations totfor three different cases . 56 Table G.2 Uncertainty budget for determinations of R0for sound power level and sound energy level using the direct method

38、, valid for A-weighted measurements of a source with a relatively flat frequency spectrum . 60 ANSI/ASA S12.51-2012 / ISO 3741:2010 vi 2012 Acoustical Society of AmericaAll rights reservedForeword This Foreword is for information only, and is not a part of the American National Standard ANSI/ASA S12

39、.51-2012 / ISO 3741:2010 American National Standard Acoustics Determination of sound power levels and sound energy levels of noise sources using sound pressure Precision methods for reverberation test rooms. This standard comprises a part of a group of definitions, standards, and specifications for

40、use in noise. It was developed and approved by Accredited Standards Committee S12, Noise, under its approved operating procedures. Those procedures have been accredited by the American National Standards Institute (ANSI). The Scope of Accredited Standards Committee S12 is as follows: Standards, spec

41、ifications, and terminology in the field of acoustical noise pertaining to methods of measurement, evaluation, and control, including biological safety, tolerance, and comfort, and physical acoustics as related to environmental and occupational noise. This standard is a revision of ANSI S12.51-2002

42、(R 2007) / ISO 3741:1999, which has been technically revised. This Standard is identical to International Standard ISO 3741, Acoustics Determination of sound power levels and sound energy levels of noise sources using sound pressure Precision methods for reverberation test rooms, which was prepared

43、by Technical Committee ISO/TC 43 Subcommittee SC 1, Noise. However, in conformance with ANSI and ISO rules, the words “American National Standard“ replace the words “International Standard“ where they appear in the ISO document, decimal points were substituted in place of the decimal commas used in

44、ISO documents, and American English spelling is used in place of British English spelling. The ANSI or ANSI/ASA equivalents for the ISO standards in the ISO 3740 series and other referenced nationally adopted standards are given below: ANSI S12.5 / ISO 6926 is an identical national adoption of ISO 6

45、926; ANSI/ASA S12.50/ISO 3740 is an identical national adoption of ISO 3740; ANSI/ASA S12.51/ISO 3741 is an identical national adoption of ISO 3741; ANSI/ASA S12.53/Part 1/ISO 3743-1 is an identical national adoption of ISO 3743-1; ANSI/ASA S12.53/Part 2/ISO 3743-2 is an identical national adoption

46、of ISO 3743-2; ANSI/ASA S12.54/ISO 3744 is an identical national adoption of ISO 3744; ANSI S12.55/ISO 3745 is an identical national adoption of ISO 3745; ANSI/ASA S12.56/ISO 3746 is an identical national adoption of ISO 3746; and ANSI/ASA S12.57/ISO 3747 is an identical national adoption of ISO 374

47、7. At the time this Standard was submitted to Accredited Standards Committee S12, Noise for approval, the membership was as follows: W.J. Murphy, Chair R.D. Hellweg, Vice-Chair S.B. Blaeser, Secretary 3M Occupational Health FAX: 631-390-0217; E-mail: asastdsaip.org. ANSI/ASA S12.51-2012 / ISO 3741:2

48、010 x 2012 Acoustical Society of AmericaAll rights reservedIntroduction This American National Standard is one of the series ISO 37402to ISO 37478, which specify various methods for determining the sound power levels and sound energy levels of noise sources including machinery, equipment and their s

49、ub-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 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 es