1、BS EN ISO8253-2:2009ICS 13.140; 17.140.50NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBRITISH STANDARDAcoustics Audiometric testmethodsPart 2: Sound field audiometry withpure-tone and narrow-band testsignals (ISO 8253-2:2009)This British Standardwas published under theauthor
2、ity of the StandardsPolicy and StrategyCommittee on 28 February2010. BSI 2010ISBN 978 0 580 64855 7Amendments/corrigenda issued since publicationDate CommentsBS EN ISO 8253-2:2009National forewordThis British Standard is the UK implementation of EN ISO 8253-2:2009.It supersedes BS EN ISO 8253-2:1998
3、 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee EH/1, Acoustics.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisionsof a contract. Use
4、rs are responsible for its correct application.Compliance with a British Standard cannot confer immunityfrom legal obligations.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 8253-2 December 2009 ICS 13.140 Supersedes EN ISO 8253-2:1998English Version Acoustics - Audiometric test methods -
5、Part 2: Sound field audiometry with pure-tone and narrow-band test signals (ISO 8253-2:2009) Acoustique - Mthodes dessais audiomtriques - Partie 2: Audiomtrie en champ acoustique avec des sons purs et des bruits bande troite comme signaux dessai (ISO 8253-2:2009) Akustik - Audiometrische Prfverfahre
6、n - Teil 2: Schallfeld-Audiometrie mit reinen Tnen und schmalbandigen Prfsignalen (ISO 8253-2:2009) This European Standard was approved by CEN on 26 October 2009. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standar
7、d 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 Standard exists in three official versions (English, French,
8、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 national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Cze
9、ch 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 United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUR
10、OPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2009 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 8253-2:2009: EBS EN ISO 8253-2:2009EN ISO 8253-2:2009 (E) 3 Foreword
11、 This document (EN ISO 8253-2:2009) has been prepared by Technical Committee ISO/TC 43 “Acoustics“ in collaboration with the Technical Committee CEN/TC 211 “Acoustics” the secretariat of which is held by DS. This European Standard shall be given the status of a national standard, either by publicati
12、on of an identical text or by endorsement, at the latest by June 2010, and conflicting national standards shall be withdrawn at the latest by June 2010. 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
13、be held responsible for identifying any or all such patent rights. This document supersedes EN ISO 8253-2:1998. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria
14、, 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. Endorsement notice The text of
15、ISO 8253-2:2009 has been approved by CEN as a EN ISO 8253-2:2009 without any modification. BS EN ISO 8253-2:2009ISO 8253-2:2009(E) ISO 2009 All rights reserved iiiContents Page Foreword iv Introduction.v 1 Scope1 2 Normative references1 3 Terms and definitions .2 4 Test signal characteristics .3 4.1
16、 General .3 4.2 Pure tones 3 4.3 FM tones.4 4.4 Narrow bands of noise4 4.5 Harmonic distortion 4 4.6 Signal gating 5 4.7 Signal level control5 4.8 Means and scales for calibration.5 5 Sound field characteristics.6 5.1 General .6 5.2 Free sound field.6 5.3 Diffuse sound field 6 5.4 Quasi-free sound f
17、ield.7 6 Ambient noise levels in the test room.7 7 Preparation and instruction of test subject7 8 Determination of hearing threshold level .8 8.1 General .8 8.2 Monaural testing8 8.3 Binaural testing .8 9 Testing with a hearing aid 8 10 Screening audiometry.8 11 Reporting of data.10 11.1 General .10
18、 11.2 Equipment calibrated by hearing level10 11.3 Equipment calibrated by sound pressure level .10 12 Maintenance and calibration of equipment 10 12.1 General .10 12.2 Intervals between tests.10 12.3 Stage A: routine examination and listening tests11 12.4 Stage B: periodic electroacoustic tests11 1
19、2.5 Stage C: basic calibration tests .12 Annex A (informative) Graphical display of results.13 Annex B (informative) Correction values for 45 and 90 angles of incidence.15 Bibliography16 BS EN ISO 8253-2:2009ISO 8253-2:2009(E) iv ISO 2009 All rights reservedForeword ISO (the International Organizati
20、on 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 interested in a subject for which a technical committee has been established ha
21、s 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 Commission (IEC) on all matters of electrotechnical standardization. Inte
22、rnational Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publica
23、tion as an International Standard requires approval by at least 75 % of the member bodies casting a vote. 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 rig
24、hts. ISO 8253-2 was prepared by Technical Committee ISO/TC 43, Acoustics. This second edition cancels and replaces the first edition (ISO 8253-2:1992), of which it constitutes a minor revision. ISO 8253 consists of the following parts, under the general title Acoustics Audiometric test methods: Part
25、 1: Basic pure-tone air and bone conduction threshold audiometry Part 2: Sound field audiometry with pure-tone and narrow-band test signals Part 3: Speech audiometry BS EN ISO 8253-2:2009ISO 8253-2:2009(E) ISO 2009 All rights reserved vIntroduction ISO 8253-1 covers procedures for the determination
26、of thresholds of hearing using pure tones presented to the subject by means of earphone or bone vibrator. This part of ISO 8253 covers procedures for the determination of thresholds of hearing in a sound field. In general, sound field testing implies binaural Iistening to a test signal, presented by
27、 means of one or more loudspeakers in a test room. The test signal may be a pure tone, a frequency-modulated tone or a narrow band of noise. The acoustical characteristics of the sound field are determined by the choice of test signal, by the number and acoustical properties of the loudspeakers used
28、, as well as by the acoustical characteristics of the test room. Sound field audiometry may be used for various purposes, e.g. the evaluation of hearing acuity in young children and the determination of the functional gain of a hearing aid when worn by a particular listener. BS EN ISO 8253-2:2009BS
29、EN ISO 8253-2:2009INTERNATIONAL STANDARD ISO 8253-2:2009(E) ISO 2009 All rights reserved 1Acoustics Audiometric test methods Part 2: Sound field audiometry with pure-tone and narrow-band test signals 1 Scope This part of ISO 8253 specifies relevant test signal characteristics, requirements for free,
30、 diffuse, and quasi-free sound fields, and procedures for sound field audiometry using pure tones, frequency-modulated tones or other narrow-band test signals presented by means of one or more loudspeakers. The primary purpose is the determination of hearing threshold levels in the frequency range 1
31、25 Hz to 8 000 Hz, but this range can be extended to 20 Hz to 16 000 Hz. This part of ISO 8253 does not include specifications for the use of hand-held loudspeakers. Speech as a test signal is not covered. The purpose of this part of ISO 8253 is to ensure that tests of hearing, using sound field aud
32、iometry, give as high a degree of accuracy and reproducibility as possible. Examples of graphical representations of the results are given in Annex A. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edit
33、ion cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 226, Acoustics Normal equal-loudness-level contours ISO 266, Acoustics Preferred frequencies ISO 389-7, Acoustics Reference zero for the calibration of audiometric equipme
34、nt Part 7: Reference threshold of hearing under free-field and diffuse-field listening conditions ISO 8253-1:1), Acoustics Audiometric test methods Part 1: Basic pure-tone air and bone conduction threshold audiometry IEC 60581-7:1986, High fidelity audio equipment and systems Minimum performance req
35、uirements Part 7: Loudspeakers IEC 60645-1, Electroacoustics Audiometric equipment Part 1: Pure-tone audiometers IEC 61672-1, Electroacoustics Sound level meters Part 1: Specifications 1) To be published. (Revision of ISO 8253-1:1989) BS EN ISO 8253-2:2009ISO 8253-2:2009(E) 2 ISO 2009 All rights res
36、erved3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 air conduction transmission of signal through the external and middle ear to the inner ear 3.2 otologically normal person person in a normal state of health who is free from all signs or sy
37、mptoms of ear disease and from obstructing wax in the ear canal, and who has no history of undue exposure to noise, exposure to potentially ototoxic drugs, or of familial hearing loss 3.3 reference point midpoint of a straight line connecting the ear canal openings of the listener when positioned in
38、 the Iistening position in the sound field 3.4 reference axis axis perpendicular to the radiating surface of the loudspeaker NOTE 1 For single radiator or horn loudspeakers, the axis passes through the geometric centre of the diaphragm or the horn. NOTE 2 For multi-unit loudspeakers, the position of
39、 the axis is defined by the manufacturer. 3.5 threshold of hearing level of a sound at which, under specified conditions, a person gives 50 % of correct detection responses on repeated trials 3.6 threshold sound pressure level for a given listener, a specified signal and a specified manner of signal
40、 presentation, sound pressure level at the reference point (3.3) in the specific sound field, in the absence of the listener, which in the presence of the listener in the test position would correspond to the threshold of hearing (3.5) of the listener 3.7 reference threshold sound pressure level for
41、 a specific signal and a specified manner of signal presentation, median value of the threshold sound pressure levels (3.6) of a sufficiently large number under test of otologically normal persons (3.2), of both genders, aged between 18 years and 25 years inclusive, expressing the threshold of heari
42、ng (3.5) at the reference point (3.3) in the specific sound field 3.8 hearing level for a specified signal and a specified manner of signal presentation, sound pressure level of this signal at the reference point (3.3) in the specific sound field minus the appropriate reference threshold sound press
43、ure level (3.7) 3.9 hearing threshold level for a specified signal and a specified sound field, threshold of hearing (3.5) expressed either as hearing level (3.8) or as sound pressure level BS EN ISO 8253-2:2009ISO 8253-2:2009(E) ISO 2009 All rights reserved 33.10 carrier frequency of a frequency-mo
44、dulated tone average value of the periodically varying tone frequency NOTE The carrier frequency is designated as the nominal test frequency. 3.11 frequency deviation maximum difference between the instantaneous frequency of the frequency-modulated tone and the carrier frequency 3.12 free sound fiel
45、d sound field where the boundaries of the room exert a negligible effect on the sound waves 3.13 quasi-free sound field sound field where the boundaries of the room exert only a moderate effect on the sound waves NOTE The requirements for a quasi-free sound field are specified in 5.4. 3.14 diffuse s
46、ound field sound field which in a given region has statistically uniform energy density, for which the directions of propagation at any point are randomly distributed 3.15 white noise noise whose power spectral density is independent of frequency 3.16 noise bandwidth difference between the upper and
47、 lower band-edge frequencies of a noise band NOTE At these frequencies the power spectral density of the noise is reduced to one-half of its average within the noise band. 3.17 centre frequency of a noise band geometric mean of the band-edge frequencies which define the noise bandwidth (3.16) 3.18 f
48、unctional gain of a hearing aid for a specified test signal, a specified type of sound field, a specified manner of signal presentation, and for a particular listener, difference in thresholds of hearing of the listener with and without the hearing aid 4 Test signal characteristics 4.1 General This
49、part of ISO 8253 covers test signals that are either pure tones, frequency-modulated (FM) tones or narrow bands of noise. 4.2 Pure tones Pure tones shall be used only in a free sound field which is in accordance with the specifications given in 5.2. NOTE In other types of sound field, pure tones may show large spatial variations in sound pressure level due to standing waves. BS EN ISO 8253-2:2009ISO 8253-2:2009(E) 4 ISO 2009 All rights reservedWhen test tones of fixed frequencies are used, they shall be ch
