1、September 2008DEUTSCHE NORM English price group 13No part of this standard may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 91.120.20!$QtW“14681
2、52www.din.deDDIN EN ISO 3382-2Acoustics Measurement of room acoustic parameters Part 2: Reverberation time in ordinary rooms (ISO 3382-2:2008)English version of DIN EN ISO 3382-2:2008-09Akustik Messung von Parametern der Raumakustik Teil 2: Nachhallzeit in gewhnlichen Rumen (ISO 3382-2:2008)Englisch
3、e Fassung DIN EN ISO 3382-2:2008-09Partially supersedesDIN EN ISO 3382:2000-03www.beuth.deDocument comprises 25 pages DIN EN ISO 3382-2:2008-09 2 National foreword This standard has been prepared by Technical Committee ISO/TC 43/SC 2 “Building acoustics” (Secretariat: DIN, Germany), in collaboration
4、 with Technical Committee CEN/TC 126 “Acoustic properties of building elements and of buildings” (Secretariat: AFNOR, France). The responsible German body involved in its preparation was the Normenausschuss Materialprfung (Materials Testing Standards Committee), Technical Committee NA 062-02-31 AA S
5、challdmmung und Schallabsorption, Messung und Bewertung. ISO 3382 consists of the following parts, under the general title Acoustics Measurement of room acoustic parameters: Part 1: Performance rooms Part 2: Reverberation time in ordinary rooms The following part is in preparation: Part 3: Open plan
6、 spaces The DIN Standards corresponding to the International Standards referred to in this document are as follows: ISO 3382-1 DIN EN ISO 3382-1 ISO 18233 DIN EN ISO 18233 IEC 61260 DIN EN 61260 Amendments This standard differs from DIN EN ISO 3382:2000-03 as follows: a) The title of the standard ha
7、s been changed. b) Auditoria and concert halls or other rooms intended for speech and music have been excluded from the scope. c) The options “Survey method” (4.3.2), “Engineering method” (4.3.3) and “Precision method” (4.3.4) have been introduced for measurements. d) Annexes A and B relating to aud
8、itorium and binaural auditorium measures have been deleted. e) Annex A “Measurement uncertainty” has been added. f) The evaluation of non-linear decay curves has been given in more detail and has been transferred into Annex B. g) Annex C “Formulas for the least-squares fit method” has been added. h)
9、 Information has been added about technical details specified in DIN EN ISO 3382-1, which is in preparation. Previous editions DIN 52216: 1965-08 DIN EN ISO 3382: 2000-03 DIN EN ISO 3382-2:2008-09 3 National Annex NA (informative) Bibliography DIN EN 61260, Electroacoustics Octave-band and fractiona
10、l-octave-band filters DIN EN ISO 3382-1, Acoustics Measurement of room acoustic parameters Part 1: Performance rooms DIN EN ISO 18233, Acoustics Application of new measurement methods in building and room acoustics DIN EN ISO 3382-2:2008-09 4 This page is intentionally blank EUROPEAN STANDARD NORME
11、EUROPENNE EUROPISCHE NORM EN ISO 3382-2 June 2008 ICS 91.120.20 Supersedes EN ISO 3382:2000English Version Acoustics - Measurement of room acoustic parameters - Part 2: Reverberation time in ordinary rooms (ISO 3382-2:2008) Acoustique - Mesurage des paramtres acoustiques des salles - Partie 2: Dure
12、de rverbration des salles ordinaires (ISO 3382-2:2008) Akustik - Messung von Parametern der Raumakustik - Teil 2: Nachhallzeit in gewhnlichen Rumen (ISO 3382-2:2008) This European Standard was approved by CEN on 22 May 2008. CEN members are bound to comply with the CEN/CENELEC Internal Regulations w
13、hich 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 Management Centre or to any CEN member. This European
14、 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 Management Centre has the same status as the official versions. CEN members are the nation
15、al standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, 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 Uni
16、ted Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: rue de Stassart, 36 B-1050 Brussels 2008 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 3382-
17、2:2008: E2 DIN EN ISO 3382-2:2008-09 EN ISO 3382-2:2008 (E) Contents Page Foreword3 Introduction .4 1 Scope 5 2 Normative references 5 3 Terms and definitions .5 4 Measurement conditions 6 4.1 General6 4.2 Equipment 7 4.3 Measurement positions.8 5 Measurement procedures .9 5.1 General9 5.2 Interrupt
18、ed noise method .9 5.3 Integrated impulse response method. 10 6 Evaluation of decay curves . 11 7 Measurement uncertainty 11 7.1 Interrupted noise method 11 7.2 Integrated impulse response method. 12 7.3 Lower limits for reliable results caused by filter and detector 12 8 Spatial averaging 12 9 Stat
19、ement of results . 13 9.1 Tables and curves 13 9.2 Test report . 13 Annex A (informative) Measurement uncertainty . 14 Annex B (informative) Evaluation of non-linear decay curves 18 Annex C (informative) Formulas for the least-squares fit method 20 Bibliography. 21 Foreword 3 This document (EN ISO 3
20、382-2:2008) has been prepared by Technical Committee ISO/TC 43 “Acoustics“ in collaboration with Technical Committee CEN/TC 126 “Acoustic properties of building elements and of buildings” the secretariat of which is held by AFNOR. This European Standard shall be given the status of a national standa
21、rd, either by publication of an identical text or by endorsement, at the latest by December 2008, and conflicting national standards shall be withdrawn at the latest by December 2008. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights
22、. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN ISO 3382:2000. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standar
23、d: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, 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. En
24、dorsement notice The text of ISO 3382-2:2008 has been approved by CEN as a EN ISO 3382-2:2008 without any modification. DIN EN ISO 3382-2:2008-09 EN ISO 3382-2:2008 (E) Introduction This part of ISO 3382 specifies three levels of measurement accuracy: survey; engineering; and precision. The main dif
25、ference concerns the number of measurement positions and thus the time required for the measurements. Annex A contains some additional information about the measurement uncertainty of the reverberation time. The introduction of the option of a survey measurement is intended to promote more frequent
26、measurement of reverberation time in rooms where it is relevant. It is obvious that a very simple measurement is better than no measurement. There are several reasons to measure reverberation time. First, the sound pressure level from noise sources, the intelligibility of speech, and the perception
27、of privacy in a room are strongly dependent on reverberation time. Rooms may include domestic rooms, stairways, workshops, industrial plants, classrooms, offices, restaurants, exhibition centres, sports halls, and railway and airport terminals. Second, reverberation time is measured to determine the
28、 correction term for room absorption inherent in many acoustic measurements, such as sound insulation measurements according to ISO 140 (all parts) and sound power measurements according to ISO 3740. In some countries, building codes specify the required reverberation times in classrooms and other c
29、ategories of room. However, in the vast majority of rooms, it is left to the design team to specify and design for a reverberation time that is reasonable for the purpose of a room. This part of ISO 3382 is intended to contribute to the general understanding and acceptance of reverberation time for
30、room quality and usability. Two different evaluation ranges are defined in this part of ISO 3382, 20 dB and 30 dB. However, a preference has been given to the 20 dB evaluation range for several reasons: a) the subjective evaluation of reverberation is related to the early part of the decay; b) for t
31、he estimation of the steady-state sound level in a room from its reverberation time, it is appropriate to use the early part of the decay: and c) the signal-to-noise ratio is often a problem in field measurements, and it is often difficult or impossible to get a evaluation range of more than 20 dB.
32、This requires a signal-to-noise level of at least 35 dB. The traditional measuring technique is based on visual inspection of every single decay curve. With modern measuring equipment, the decay curves are normally not displayed and this may introduce a risk that abnormal decay curves are used for t
33、he determination of the reverberation time. For this reason, Annex B introduces two new measures that quantify the degree of non-linearity and the degree of curvature of the decay curve. These measures may be used to give warnings when the decay curve is not linear, and consequently the result shoul
34、d be marked as less reliable and not having a unique reverberation. The use of rotating microphones during the measurement of decay curves has been considered by the working group, and this procedure is found to be without a clear physical meaning and thus it is only accepted for the interrupted noi
35、se method and only when the result is used for a correction term. For other reverberation time measurements, ISO 3382-1 covers auditoria and performance spaces, and ISO 354 absorption coefficient measurements in a reverberation room. Neither ISO 3382-1 nor ISO 354 is suitable for measurements in roo
36、ms like those mentioned above. Thus, this part of ISO 3382 fills a gap among measurement standards for acoustic properties of buildings. This part of ISO 3382 does not repeat the technical details of ISO 3382-1, but deals with the measurement of reverberation time, only, in any kind of room. 4 DIN E
37、N ISO 3382-2:2008-09 EN ISO 3382-2:2008 (E) 1 Scope This part of ISO 3382 specifies methods for the measurement of reverberation time in ordinary rooms. It describes the measurement procedure, the apparatus needed, the required number of measurement positions, and the method for evaluating the data
38、and presenting the test report. The measurement results can be used for correction of other acoustic measurements, e.g. sound pressure level from sound sources or measurements of sound insulation, and for comparison with requirements for reverberation time in rooms. 2 Normative references The follow
39、ing referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 3382-1:1), Acoustics Measurement of room acoustic param
40、eters Part 1: Performance rooms ISO 18233, Acoustics Application of new measurement methods in building and room acoustics IEC 61260, Electroacoustics Octave-band and fractional-octave-band filters 3 Terms and definitions For the purposes of this document, the following terms and definitions apply.
41、3.1 decay curve graphical representation of the decay of the sound pressure level in a room as a function of time after the sound source has stopped ISO 354:2003, 3.1 NOTE It is possible to measure this decay either after the actual cut-off of a continuous sound source in the room or derived from th
42、e reverse-time integrated squared impulse response of the room, see Clause 5. 1) To be published. (Revision of ISO 3382:1997) 5 DIN EN ISO 3382-2:2008-09 EN ISO 3382-2:2008 (E) 3.2 interrupted noise method method of obtaining decay curves by direct recording of the decay of sound pressure level afte
43、r exciting a room with broadband or band-limited noise ISO 354:2003, 3.3 3.3 integrated impulse response method method of obtaining decay curves by reverse-time integration of squared impulse responses ISO 354:2003, 3.4 3.4 impulse response temporal evolution of the sound pressure observed at a poin
44、t in a room as a result of the emission of a Dirac impulse at another point in the room ISO 354:2003, 3.5 NOTE It is impossible in practice to create and radiate true Dirac delta functions but short transient sounds (e.g. from gunshots) can offer close enough approximations for practical measurement
45、. An alternative measurement technique, however, is to use a period of maximum-length sequence (MLS) type signal or other deterministic, flat-spectrum signal like a sine sweep and transform the measured response back to an impulse response. 3.5 reverberation time T room acoustic parameters duration
46、required for the space-averaged sound energy density in an enclosure to decrease by 60 dB after the source emission has stopped NOTE 1 The reverberation time is expressed in seconds. NOTE 2 T can be evaluated based on a smaller dynamic range than 60 dB and extrapolated to a decay time of 60 dB. It i
47、s then labelled accordingly. Thus, if T is derived from the time at which the decay curve first reaches 5 dB and 25 dB below the initial level, it is labelled T20. If decay values of 5 dB to 35 dB below the initial level are used, it is labelled T30. 3.6 large room volume an enclosed space of volume
48、 greater than 300 m34 Measurement conditions 4.1 General In many rooms, the number of people present can have a strong influence on the reverberation time. Reverberation time measurements should be made in a room containing no people. However, a room with up to two persons present may be allowed to
49、represent its unoccupied state, unless otherwise specified. If the measurement result is used for correction of a measured sound pressure level, the number of persons present in the room should be the same for that measurement. In large rooms, attenuation by air can contribute significantly to sound absorption at high frequencies. For precision measurements, the temperature and relative humidity of the air in the room shall normally be measured. The contribution from air absorption is negligible if the reverberation time is sho
