1、BSI Standards PublicationBS 4142:2014Methods for rating andassessing industrial andcommercial soundPublishing and copyright informationThe BSI copyright notice displayed in this document indicates when the documentwas last issued. The British Standards Institution 2014Published by BSI Standards Limi
2、ted 2014ISBN 978 0 580 80051 1ICS 17.140.20; 91.120.20The following BSI references relate to the work on this document:Committee reference EH/1/3Draft for comment 14/30268407 DCPublication historyFirst published March 1967Second edition November 1990Third edition September 1997Fourth edition October
3、 2014Amendments issued since publicationDate Text affectedBS 4142:2014 BRITISH STANDARDContentsForeword iii1 Scope 12 Normative references 23 Terms and definitions 24 Preparation 35 Instrumentation 46 Measurement procedure 47 Specific sound level 68 Background sound level 109 Rating level 1310 Uncer
4、tainty 1511 Assessment of the impacts 1612 Information to be reported 18AnnexesAnnex A (informative) Examples of how to use the standard to obtainratings 20Annex B (informative) Consideration of uncertainty and good practice forreducing uncertainty 47Annex C (normative) Objective method for assessin
5、g the audibility of tones insound: One-third octave method 53Annex D (normative) Objective method for assessing the audibility of tones insound: Reference method 53Annex E (normative) Objective method for measuring the prominence ofimpulsive sounds and for adjustment of LAeq63Bibliography 68List of
6、figuresFigure 1 Selecting the measurement time interval 9Figure 2 Selecting the measurement time interval 9Figure 3 Selecting the measurement time interval 10Figure 4 Example of a statistical analysis to determine the background soundlevel 12Figure A.1 Sound level variation with time 20Figure A.2 Me
7、asurement of the factory sound affected by the residualnoise 23Figure A.3 Sound level variations with time 24Figure A.4 Specific sound cycling on and off 26Figure A.5 Sound level outside bedroom window with intermittent plantoperation: LAeqfor entire period 40 dB, residual LAeqwhen no vehicles passi
8、ng28 dB, background LA9027 dB, ambient LAeqwith plant on 36 dB 34Figure A.6 Sound level on patio in rear garden with intermittent plantoperation: LAeqfor entire period 43 dB, residual LAeqwhen no vehicles passing31 dB, background LA9030 dB, ambient LAeqwith plant on 39 dB 38Figure A.7 Sound level ou
9、tside bedroom window with intermittent plantoperation: LAeqfor entire period 45 dB, residual LAeqwhen no vehicles passing33 dB, background LA9032 dB, ambient LAeqwith plant on 41 dB 42Figure A.8 Sound level variation with time 43Figure A.9 Measurement locations 45Figure A.10 Measurement locations 46
10、Figure D.1 Determination of tonal audibility, Lta,and adjustment, Kt56Figure D.2 Definitions of tones, noise, and noise pause (neither tone nornoise) 58Figure D.3 Example 1 61Figure D.4 Example 2 61Figure D.5 Example 3 62Figure D.6 Example 4 63BRITISH STANDARD BS 4142:2014 The British Standards Inst
11、itution 2014 iFigure E.1 Time history of the A-weighted sound pressure levels with timeweighting F 64List of tablesTable A.1 Example 1: Assessment 21Table A.2 Example 2: Assessment 22Table A.3 Example 3: Assessment 25Table A.4 Example 4: Assessment 27Table A.5 Example 5: Assessment 30Table A.6 Examp
12、le 6: Assessment 32Table A.7 Example 7: Assessment 36Table A.8 Example 8: Assessment 40Table A.9 Example 9: Assessment 44Table A.10 Example 11: Assessment 47Table D.1 Widths of critical bands 55Table E.1 Examples of the prominence P and the adjustment KIfor differentsound sources 66Summary of pagesT
13、his document comprises a front cover, an inside front cover, pages i to iv,pages 1 to 72, an inside back cover and a back cover.BRITISH STANDARDBS 4142:2014ii The British Standards Institution 2014ForewordPublishing informationThis British Standard is published by BSI Standards Limited, under licenc
14、e fromThe British Standards Institution, and came into effect on 31 October 2014. Itwas prepared by Sub-committee EH/1/3, Residential and industrial noise, underthe authority of Technical Committee EH/1, Acoustics. A list of organizationsrepresented on these committees can be obtained on request to
15、their secretary.SupersessionThis British Standard supersedes BS 4142:1997, which is withdrawn.Information about this documentBS 4142 was first published in 1967, and was revised in 1990 to align it withelements of ISO 1996. The 1997 edition clarified aspects of the standard in thelight of comments f
16、rom users.This edition has been prepared under the direction of the Health andEnvironment Sector Board. The general basis for the standard is derived fromthe application of previous editions, together with accumulated experience.Some aspects, including guidance on character corrections, are based up
17、onresearch which has been reported since publication of the previous edition ofthis standard.This edition clarifies the application of the standard. New to this edition is theintroduction of uncertainty, including good practice for reducing uncertainty.The examples in Annex A have been considerably
18、expanded.Response to sound can be subjective and is affected by many factors, bothacoustic and non-acoustic. The significance of its impact, for example, candepend on such factors as the margin by which a sound exceeds the backgroundsound level, its absolute level, time of day and change in the acou
19、sticenvironment, as well as local attitudes to the source of the sound and thecharacter of the neighbourhood. This edition of the standard recognizes theimportance of the context in which a sound occurs. Great care has, therefore,been taken in the use of the words “sound” and “noise”. Sound can beme
20、asured by a sound level meter or other measuring system. Noise is related toa human response and is routinely described as unwanted sound, or sound thatis considered undesirable or disruptive.The documents available as downloads from the sites referenced in theBibliography were last accessed on 30 O
21、ctober 2014.Use of this documentIt has been assumed in the preparation of this British Standard that theexecution of its provisions will be entrusted to appropriately qualified andexperienced people, for whose use it has been produced.Presentational conventionsThe guidance in this standard is presen
22、ted in roman (i.e. upright) type. Anyrecommendations are expressed in sentences in which the principal auxiliaryverb is “should”.Commentary, explanation and general informative material are presented insmaller italic type.BRITISH STANDARD BS 4142:2014 The British Standards Institution 2014 iiiContra
23、ctual and legal considerationsThis publication does not purport to include all the necessary provisions of acontract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legalobligations.BRITISH STANDARDBS 4142:2014iv The British Standards
24、 Institution 20141 Scope1.1 This British Standard describes methods for rating and assessing sound of anindustrial and/or commercial nature, which includes:a) sound from industrial and manufacturing processes;b) sound from fixed installations which comprise mechanical and electricalplant and equipme
25、nt;c) sound from the loading and unloading of goods and materials at industrialand/or commercial premises; andd) sound from mobile plant and vehicles that is an intrinsic part of the overallsound emanating from premises or processes, such as that from forklifttrucks, or that from train or ship movem
26、ents on or around an industrialand/or commercial site.The methods described in this British Standard use outdoor sound levels toassess the likely effects of sound on people who might be inside or outside adwelling or premises used for residential purposes upon which sound is incident.NOTE Examples o
27、f how ratings might be obtained using this standard are given inAnnex A.1.2 This standard is applicable to the determination of the following levels atoutdoor locations:a) rating levels for sources of sound of an industrial and/or commercial nature;andb) ambient, background and residual sound levels
28、,for the purposes of:1) investigating complaints;2) assessing sound from proposed, new, modified or additional source(s) ofsound of an industrial and/or commercial nature; and3) assessing sound at proposed new dwellings or premises used for residentialpurposes.1.3 The determination of noise amountin
29、g to a nuisance is beyond the scope ofthis British Standard.Sound of an industrial and/or commercial nature does not include sound fromthe passage of vehicles on public roads and railway systems.The standard is not intended to be applied to the rating and assessment ofsound from:a) recreational acti
30、vities, including all forms of motorsport;b) music and other entertainment;c) shooting grounds;d) construction and demolition;e) domestic animals;f) people;g) public address systems for speech; andh) other sources falling within the scopes of other standards or guidance.The standard is not intended
31、to be applied to the derivation of indoor soundlevels arising from sound levels outside, or the assessment of indoor soundlevels.BRITISH STANDARD BS 4142:2014 The British Standards Institution 2014 1The standard is not applicable to the assessment of low frequency noise.NOTE Information on the asses
32、sment of low frequency noise is given inNANR45 1, 2.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in thisdocument and are indispensable for its application. For dated references, onlythe edition cited applies. For undated references, the latest editio
33、n of thereferenced document (including any amendments) applies.BS EN 60942, Electroacoustics Sound calibratorsBS EN 61260, Electroacoustics Octave-band and fractional-octave-band filtersBS EN 61672-1, Electroacoustics Sound level meters Part 1: Specifications3 Terms and definitionsFor the purposes o
34、f this British Standard, the following terms and definitionsapply.NOTE All the measurements and values used throughout this standard are“A”-weighted. Where “A” weighting is not explicit in the descriptor, it is to beassumed in all cases, except where it is clearly stated that it is not applicable, a
35、s inthe case of tones.3.1 acoustic environmentsound from all sound sources as modified by the environmentBS ISO 12913-1:20133.2 ambient soundtotally encompassing sound in a given situation at a given time, usuallycomposed of sound from many sources near and farNOTE The ambient sound comprises the re
36、sidual sound and the specific soundwhen present.3.3 ambient sound level, La=LAeq,Tequivalent continuous A-weighted sound pressure level of the totallyencompassing sound in a given situation at a given time, usually from manysources near and far, at the assessment location over a given time interval,
37、 TNOTE The ambient sound level is a measure of the residual sound and the specificsound when present.3.4 background sound level, LA90,TA-weighted sound pressure level that is exceeded by the residual sound at theassessment location for 90% of a given time interval, T, measured using timeweighting F
38、and quoted to the nearest whole number of decibels3.5 equivalent continuous A-weighted sound pressure level, LAeq,Tvalue of the A-weighted sound pressure level in decibels of continuous steadysound that, within a specified time interval, T = t2 t1, has the samemean-squared sound pressure as a sound
39、that varies with time, and is given bythe following equation:BRITISH STANDARDBS 4142:20142 The British Standards Institution 2014LAeq,T510lg10H(1TH20850et1t2pA(t)2/p02dtJ(1)where:p0is the reference sound pressure (20 Pa); andpA(t) is the instantaneous A-weighted sound pressure (Pa) at time tNOTE The
40、 equivalent continuous A-weighted sound pressure level is quoted to thenearest whole number of decibels.3.6 measurement time interval, Tmtotal time over which measurements are takenNOTE This may consist of the sum of a number of non-contiguous, short-termmeasurement time intervals.3.7 rating level,
41、LAr,Trspecific sound level plus any adjustment for the characteristic features of thesound3.8 reference time interval, Trspecified interval over which the specific sound level is determinedNOTE This is 1 h during the day from 07:00 h to 23:00 h and a shorter period of15 min at night from 23:00 h to
42、07:00 h.3.9 residual soundambient sound remaining at the assessment location when the specific soundsource is suppressed to such a degree that it does not contribute to the ambientsound3.10 residual sound level, Lr=LAeq,Tequivalent continuous A-weighted sound pressure level of the residual sound att
43、he assessment location over a given time interval, T3.11 specific sound level, Ls=LAeq,Trequivalent continuous A-weighted sound pressure level produced by the specificsound source at the assessment location over a given reference time interval, Tr3.12 specific sound sourcesound source being assessed
44、4 PreparationThe assessor should gain a sufficient understanding of the situation (context) tobe rated and assessed by conducting an appraisal, as appropriate, in order to:a) identify and understand all the sounds that can be heard, and identify theirsources;b) identify which measurement methods, in
45、struments and metrics (seeClause 5) would be most appropriate for the assessment;c) identify potential measurement locations;d) identify the necessary measurement frequencies, durations and timings; ande) where a new development is to be assessed, understand what kind of sounda new industrial source
46、 would introduce, or what potential impact would beimposed from an existing source on a new sensitive receptor.BRITISH STANDARD BS 4142:2014 The British Standards Institution 2014 35 Instrumentation5.1 GeneralSelect systems for measuring sound pressure levels, including microphone(s),cable(s), winds
47、creen(s), recording devices and other accessories which conform toBS EN 61672-1, Class 1, for free-field application, as appropriate. Filters, whereused, should conform to BS EN 61260, Class 1, and sound calibrators toBS EN 60942, Class 1.NOTE It is also acceptable to use measuring systems conformin
48、g to BS EN 60804,Type 1, and BS EN 60651, Type 1.5.2 VerificationDemonstrate conformity of the measuring system, filters where appropriate andsound calibrators with the provisions of 5.1 by means of valid certificatesshowing conformity to each relevant standard following testing according to theappr
49、opriate part of that standard.NOTE 1 It is recommended that sound calibrators are calibrated at intervals notexceeding 1 year, conformity of the measuring systems to BS EN 61672-1 is verifiedat intervals not exceeding 2 years, and the conformity of filters to BS EN 61260 isverified at intervals not exceeding 2 years.NOTE 2 It is also acceptable to verify measuring systems conforming toBS EN 60804, Type 1, and BS EN 60651, Type 1, in accordance with BS 7580-1.6 Measurement procedure6.1 F
