1、BRITISH STANDARDBS EN 60318-5:2006Electroacoustics Simulators of human head and ear Part 5: 2 cm coupler for the measurement of hearing aids and earphones coupled to the ear by means of ear insertsThe European Standard EN 60318-5:2006 has the status of a British StandardICS 17.140.50g49g50g3g38g50g5
2、1g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN 60318-5:2006This British Standard was published under the authority of the Standards Policy and Strategy Commi
3、ttee on 31 October 2006 BSI 2006ISBN 0 580 49417 9National forewordThis British Standard was published by BSI. It is the UK implementation of EN 60318-5:2006. It is identical with IEC 60318-5:2006. It supersedes BS 6111:1981 which is withdrawn.The UK participation in its preparation was entrusted to
4、 Technical Committee EPL/29, Electroacoustics.A list of organizations represented on EPL/29 can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British
5、 Standard cannot confer immunity from legal obligations.Amendments issued since publicationAmd. No. Date CommentsEUROPEAN STANDARD EN 60318-5 NORME EUROPENNE EUROPISCHE NORM September 2006 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique
6、 Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 1050 Brussels 2006 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 60318-5:2006 E ICS 17.140.50 English version Electroacoustics - Simu
7、lators of human head and ear Part 5: 2 cm coupler for the measurement of hearing aids and earphones coupled to the ear by means of ear inserts (IEC 60318-5:2006) Electroacoustique - Simulateurs de tte et doreille humaines Partie 5: Coupleur de 2 cm pour la mesure des appareils de correction auditive
8、 et des couteurs coupls loreille par des embouts (CEI 60318-5:2006) Elektroakustik - Simulatoren des menschlichen Kopfes und Ohres Teil 5: 2-cm-Kuppler zur Messung von mittels Ohreinstzen angekoppelten Hrgerten und Ohrhrern (IEC 60318-5:2006) This European Standard was approved by CENELEC on 2006-09
9、-01. CENELEC 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 lists and bibliographical references concerning such national standards may be obta
10、ined on application to the Central Secretariat or to any CENELEC member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Cent
11、ral Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
12、Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. EN 60318-5:2006 2 Foreword The text of document 29/600/FDIS, future edition 1 of IEC 60318-5, prepared by IEC TC 29, Electroacoustics, was submitted to the IEC-CENELEC parallel vote
13、 and was approved by CENELEC as EN 60318-5 on 2006-09-01. The following dates were fixed: latest date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2007-06-01 latest date by which the national standards conflicting wi
14、th the EN have to be withdrawn (dow) 2009-09-01 Annex ZA has been added by CENELEC. _ Endorsement notice The text of the International Standard IEC 60318-5:2006 was approved by CENELEC as a European Standard without any modification. In the official version, for Bibliography, the following notes hav
15、e to be added for the standards indicated: IEC 60118-7 NOTE Harmonized as EN 60118-7:2005 (not modified). IEC 61094-1 NOTE Harmonized as EN 61094-1:1994 (not modified). _ 3 EN 60318-5:2006 CONTENTS 1 Scope 4 2 Normative references .4 3 Terms and definitions .4 4 Construction.5 4.1 General .5 4.2 Cav
16、ity dimensions .5 4.3 Calibrated pressure type microphone .5 4.4 Static pressure equalisation.6 5 Calibration6 5.1 Reference environmental conditions.6 5.2 Calibration procedure 6 6 Coupling of earphones and hearing aids to the coupler7 6.1 Audiometers with insert earphones 7 6.2 Hearing aids of the
17、 in-the-ear type .7 6.3 Hearing aids with insert earphone 7 6.4 Hearing aids of the behind-the-ear type and spectacle hearing aids10 7 Maximum permitted expanded uncertainty of measurements .12 7 Annex ZA (normative) Normative references to international publications with their corresponding Europea
18、n publications.14 Bibliography .13 EN 60318-5:2006 4 ELECTROACOUSTICS SIMULATORS OF HUMAN HEAD AND EAR Part 5: 2 cm3 coupler for the measurement of hearing aids and earphones coupled to the ear by means of ear inserts 1 Scope This part of IEC 60318 describes an acoustic coupler for loading an earpho
19、ne or hearing aid with a specified acoustic impedance when determining its physical performance character-istics, in the frequency range 125 Hz to 8 kHz. It is suitable for air conduction hearing aids and earphones, coupled to the ear by means of ear inserts e.g. ear moulds or similar devices. The s
20、ound pressure developed by an earphone is not, in general, the same in the coupler as in a persons ear. However, it can be used as a simple and ready means for the exchange of specifications and of physical data on hearing aids and for the calibration of specified insert earphones used in audiometry
21、. 2 Normative references The following 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. IEC 61094-4, Measurement
22、 microphones Part 4: Specifications for working standard microphones ISO 389-2, Acoustics Reference zero for the calibration of audiometric equipment Part 2: Reference equivalent threshold sound pressure levels for pure tones and insert earphones BIPM/IEC/ISO/IUPAC/IUPAP/OIML:1995, Guide to the expr
23、ession of uncertainty in measurement (GUM) 3 Terms and definitions For the purposes of this part of IEC 60318, the following terms and definitions apply: 3.1 acoustic coupler cavity of predetermined shape and volume which is used for the calibration of an earphone in conjunction with a microphone to
24、 measure the sound pressure developed within the cavity 3.2 effective volume equivalent volume of air of the acoustical compliance of the coupler formed by the cavity and the microphone at a frequency of 250 Hz 5 EN 60318-5:2006 4 Construction 4.1 General The coupler consists essentially of a cylind
25、rical cavity whose effective volume is nominally 2 000 mm3. The base of the cylindrical cavity contains the diaphragm of a microphone, or a microphone with an adapter. A protection grid may or may not be fitted. The microphone measures the sound pressure level in the coupler. The coupler shall be co
26、nstructed of hard, dimensionally stable, non-porous and non-magnetic material. The general construction of the coupler and mounting of the microphone shall aim to minimise the response of the microphone to vibration (for example from an earphone) or to extraneous sound outside the cavity. NOTE The e
27、xternal diameter of the coupler should be kept as small as possible in order to minimise diffractional errors which might affect the measurements when the coupler has to be placed in a free sound field. Where tolerances are specified in this part of IEC 60318, these shall be reduced by an amount equ
28、al to the actual expanded measurement uncertainty of the test laboratory before deciding if a device conforms with the stated requirement. 4.2 Cavity dimensions 4.2.1 The critical dimensions of the coupler are those which determine the shape and volume of the cavity terminated by a measurement micro
29、phone, and the capillary leak. 4.2.2 The effective volume of the coupler shall be: 2 000 mm3 70 mm3. The contributions of any front cavity associated with the microphone and of the finite diaphragm impedance, etc., shall be included in the effective volume of the coupler. Therefore, the height of th
30、e cylindrical cavity should be designed such that the effective volume of the coupler conforms to the requirement for all models of microphone intended for use with the coupler. 4.2.3 The diameter d1of the cylindrical cavity shall be within 18,0 mm d1 21,0 mm. 4.3 Calibrated pressure type microphone
31、 4.3.1 General A coupler configuration using a WS1P microphone shall be used for the calibration of audiometers equipped with an insert earphone. The overall pressure sensitivity level of the microphone and the associated measuring system shall be known by calibration with an expanded measurement un
32、certainty (k = 2) of no more than 0,2 dB, over the frequency range covered by the audiometer. For other purposes for instance for hearing aid measurements other microphones, including those with smaller dimensions, can be used provided that the specified volume is preserved. The use of an alternativ
33、e microphone and the associated measurement uncertainty of the pressure sensitivity level shall be stated by the user. EN 60318-5:2006 6 4.3.2 Microphone type WS1P The diameter of the free portion of the diaphragm of the microphone shall not exceed the diameter of the cylindrical cavity. The interna
34、l shape of the base of the coupler shall enable a microphone type WS1P (as specified in IEC 61094-4), without its protecting grid, to be fitted into the base. The microphone used shall have a high acoustical impedance such that its equivalent volume shall be less than 200 mm3at frequencies between 1
35、25 Hz and 8 000 Hz. NOTE A measurement microphone that conforms to the requirements of IEC 61094-1 for laboratory standard microphones also conforms to the requirements of IEC 61094-4 for working standard microphones. 4.3.3 Alternative microphone If it is necessary to use a microphone for which the
36、diameter of the free part of the diaphragm is less than the diameter of the coupler cavity, the microphone shall be located concentrically in the base of the coupler cavity. Preferably a microphone type WS2P (as specified in IEC 61094-4), either with or without protection grid, should be used. NOTE
37、1 When a type WS2P microphone is used in place of a type WS1P, differences in the coupler output levels of up to 1 dB for frequencies up to 6 kHz, and 2 dB for frequencies between 6 kHz and 8 kHz, may be expected. Similar data for other types of microphone for instance for electret microphones are n
38、ot available. NOTE 2 A measurement microphone that conforms to the requirements of IEC 61094-1 for laboratory standard microphones also conforms to the requirements of IEC 61094-4 for working standard microphones. NOTE 3 Measurements performed with a WS2P microphone equipped with a protection grid a
39、nd with an LS2P microphone should not differ by more than 0,3 dB at frequencies up to 8 kHz. 4.4 Static pressure equalisation Any change in the static pressure within the cavity caused by assembly of the earphone to the coupler and microphone shall decay toward the static ambient pressure with a tim
40、e constant of less than 1,5 seconds. If this necessitates the introduction of a controlled leak in the coupler, it shall have the following characteristics. a) It shall not alter the cavity volume by more than 20 mm3. b) It shall attenuate external sound reaching the cavity, with the entrance blocke
41、d, by at least 16 dB at 100 Hz, increasing by 6 dB per octave for increasing frequency. NOTE Equalisation can be realised, for example, by a capillary tube with a diameter of 0,6 mm and a length of 12,5 mm containing a wire with a diameter of 0,5 mm. 5 Calibration 5.1 Reference environmental conditi
42、ons Reference ambient pressure: 101,325 kPa Reference temperature: 23 C Reference relative humidity: 50 %. 5.2 Calibration procedure The manufacturer shall describe a calibration method for the microphone system used in the coupler in an instruction manual. 7 EN 60318-5:2006 Ideally, the calibration
43、 should be performed at the reference environmental conditions given in 5.1 with the following tolerances: Ambient pressure: 3,000 kPa Temperature: 3 C Relative humidity: 20 %. If it is not possible to fulfil these requirements, the actual environmental conditions shall be stated. 6 Coupling of earp
44、hones and hearing aids to the coupler 6.1 Audiometers with insert earphones Insert earphones with standardised reference equivalent threshold sound pressure levels shall be connected to the acoustic coupler as specified in the relevant ISO standard. For other earphones the manufacturer of the audiom
45、eter shall describe the method of connection. NOTE Reference equivalent threshold sound pressure levels of an insert earphone for audiometers and its connection to the 2 cm3coupler are standardised in ISO 389-2. 6.2 Hearing aids of the in-the-ear type The hearing aid shall be connected directly to t
46、he cavity of the coupler as indicated in Figure 1. The connection between the hearing aid and the coupler shall be made airtight by using a suitable seal. In doing so care shall be taken not to introduce additional volume to the cavity which can affect the measured performance of the hearing aid. 6.
47、3 Hearing aids with insert earphone Where possible, the ear insert used with the human ear shall be replaced by an ear mould substitute consisting essentially of a rigid tube, connected coaxial with the cavity, of length 18,00 mm 0,20 mm and internal diameter 3,00 mm 0,06 mm representing the tubular
48、 portion of an average ear mould. The connection between the nub of the earphone and the ear mould substitute shall be made airtight by using a suitable seal. In doing so care shall be taken not to introduce additional volume to the cavity which can affect the measured performance of the earphone. A
49、n example of an earphone connected to the 2 cm3 coupler with an ear mould substitute is shown in Figure 2. It illustrates the principle features of the connection method. However other forms may also be used, provided that they conform to the above specifications. If it is inappropriate to disconnect the ear insert used with the human ear from the receiver, the ear insert shall be connected directly to the entrance of the cylindrical cavity and shall be coaxial with it. An airtight
