1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationElectroacoustics Audiometric equipment Part 7: Instruments for the measurement of auditory brainstem responsesBS EN 60645-7:2010National forewordThis British Standard is the UK i
2、mplementation of EN 60645-7:2010. It isidentical to IEC 60645-7:2009.The UK participation in its preparation was entrusted to Technical CommitteeEPL/29, Electroacoustics.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport
3、 to include all the necessary provisions of acontract. Users are responsible for its correct application. BSI 2010 ISBN 978 0 580 60926 8 ICS 13.140; 17.140.50Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was published under the authority of t
4、he Standards Policy and Strategy Committee on 28 February 2010Amendments issued since publicationAmd. No. Date Text affectedBRITISH STANDARDBS EN 60645-7:2010EUROPEAN STANDARD EN 60645-7 NORME EUROPENNE EUROPISCHE NORM January 2010 CENELEC European Committee for Electrotechnical Standardization Comi
5、t Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: Avenue Marnix 17, B - 1000 Brussels 2010 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 60645-7:2010 E ICS 17.140.5
6、0 English version Electroacoustics - Audiometric equipment - Part 7: Instruments for the measurement of auditory brainstem responses (IEC 60645-7:2009) Electroacoustique - Appareillage audiomtrique - Partie 7: Instruments pour la mesure des rponses du tronc crbral une stimulation auditive (CEI 60645
7、-7:2009) Akustik - Audiometer - Teil 7: Gerte zur Messung von akustisch evozierten Potentialen (IEC 60645-7:2009) This European Standard was approved by CENELEC on 2009-12-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
8、 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 Central Secretariat or to any CENELEC member. This European Standard exists in three official versions
9、 (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 Central Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Aus
10、tria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United
11、Kingdom. EN 60645-7:2010 - 2 - Foreword The text of document 29/674/FDIS, future edition 1 of IEC 60645-7, prepared by IEC TC 29, Electroacoustics, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 60645-7 on 2009-12-01. The following dates were fixed: latest date by w
12、hich the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2010-09-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2012-12-01 Annex ZA has been added by CENELEC. _ Endorsement notice T
13、he text of the International Standard IEC 60645-7:2009 was approved by CENELEC as a European Standard without any modification. In the official version, for Bibliography, the following note has to be added for the standard indicated: IEC 60601-2-40 NOTE Harmonized as EN 60601-2-40 (not modified). _
14、BS EN 60645-7:2010- 3 - EN 60645-7:2010 Annex ZA (normative) Normative references to international publications with their corresponding European publications The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited appli
15、es. For undated references, the latest edition of the referenced document (including any amendments) applies. NOTE When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD applies. Publication Year Title EN/HD Year IEC 60601-1 - Medical elec
16、trical equipment - Part 1: General requirements for basic safety and essential performance EN 60601-1 - IEC 60645-1 2001 Electroacoustics - Audiological equipment - Part 1: Pure-tone audiometers EN 60645-1 2001 IEC 60645-3 2007 Electroacoustics - Audiometric equipment - Part 3: Test signals of short
17、 duration EN 60645-3 2007 ISO 389 Series Acoustics - Reference zero for the calibration of audiometric equipment - - ISO/IEC Guide 98-3 - Uncertainty of measurement - Part 3: Guide to the expression of uncertainty in measurement (GUM:1995) - - BS EN 60645-7:2010 2 60645-7 IEC:2009 CONTENTS INTRODUCT
18、ION.5 1 Scope.6 2 Normative references .6 3 Terms and definitions .6 4 Requirements for specific instruments 7 5 General specifications 8 5.1 Measuring system .8 5.1.1 Units of measurement8 5.1.2 Measurement range.8 5.1.3 Time resolution8 5.2 Stimulus system 8 5.2.1 General requirements 8 5.2.2 Stim
19、ulus types.8 5.3 Test quality assuring system .8 5.3.1 Recording conditions .8 5.3.2 Response detection.9 5.3.3 Quality estimates.9 5.3.4 Reference values.9 5.4 Presentation of results 9 6 Demonstration of conformity with specifications9 6.1 General .9 6.2 Signal-to-noise ratio improvement .9 6.3 Ma
20、ximum permitted expanded uncertainty of measurements Umax.9 7 General requirements.10 7.1 Marking .10 7.2 Instruction manual.10 7.3 Safety requirements 10 7.3.1 General .10 7.3.2 Immunity to power and radiofrequency fields .10 7.4 Warm-up time10 7.5 Voltage supply variation and environmental conditi
21、ons 11 7.5.1 Mains operation.11 7.5.2 Battery operation .11 7.5.3 Environmental conditions.11 8 Routine calibration .11 Bibliography12 Table 1 Instrumentation requirements 7 Table 2 Documentation of test conditions, parameters and results .9 Table 3 Values of Umaxfor basic measurements 10 BS EN 6064
22、5-7:201060645-7 IEC:2009 5 INTRODUCTION Developments in the field of diagnostic hearing measurement have resulted in a number of instruments designed to evaluate the auditory evoked potentials of the human hearing system which can be evoked by acoustic or vibratory signals having different spectral
23、and temporal characteristics. The practical use of such instruments concerns the measurement of these electric potentials and their separation from electric signals emerging from other physiological or artificial sources. BS EN 60645-7:2010 6 60645-7 IEC:2009 ELECTROACOUSTICS AUDIOMETRIC EQUIPMENT P
24、art 7: Instruments for the measurement of auditory brainstem responses 1 Scope This part of IEC 60645 applies to instruments designed for the measurement of auditory evoked potentials from the inner ear, the auditory nerve and the brainstem, evoked by acoustic and/or vibratory stimuli of short durat
25、ion. This part of IEC 60645 defines the characteristics to be specified by the manufacturer, specifies performance requirements for two types of instrument, screening and diagnostic, and specifies the functions to be provided on these types. The purpose of this part of IEC 60645 is to ensure that me
26、asurements made under comparable test conditions with different instruments complying with this standard will be consistent. This part of IEC 60645 is not intended to restrict development or incorporation of new features, nor to discourage innovative approaches. The application of electric stimuli f
27、or special purposes is beyond the scope of this standard. 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 (inc
28、luding any amendments) applies. IEC 60601-1, Medical electrical equipment Part 1: General requirements for basic safety and essential performance IEC 60645-1:2001, Electroacoustics Audiological equipment Part 1: Pure-tone audiometers IEC 60645-3:2007, Electroacoustics Audiometric equipment Part 3: T
29、est signals of short duration ISO 389 (all parts), Acoustics Reference zero for the calibration of audiometric equipment ISO/IEC Guide 98-3, Uncertainty of measurement Part 3: Guide to the expression of uncertainty in measurement (GUM:1995) 3 Terms and definitions For the purposes of this document,
30、the following terms and definitions apply. 3.1 auditory evoked potentials AEP electric potentials which can be evoked by acoustic or vibratory stimulation of the auditory system and recorded by means of electrodes BS EN 60645-7:201060645-7 IEC:2009 7 3.2 electric response audiometry ERA method for r
31、ecording the AEPs 3.3 auditory brainstem response ABR transient AEPs generated in the inner ear, the auditory nerve and the brainstem after stimulation of the ear with an acoustic or vibratory force stimulus of short duration NOTE A method for recording the ABRs is also known as BERA (brainstem elec
32、tric response audiometry). 3.4 automated auditory brainstem response AABR automatic detection of auditory brainstem responses 4 Requirements for specific instruments Two different types of ERA instrument are specified by the requirements for minimum mandatory functions (see Table 1). Other functions
33、 are not precluded. The two types relate to their presumed primary application (diagnostic/clinical and screening). Table 1 Instrumentation requirements Type Feature 1 Diagnostic/clinical 2 Screening Stimulus Stimulus according to IEC 60645-3 x x1Adjustable stimulus level, level control x Contra-lat
34、eral masking facility x2Signal processing Artefact rejection x x User adjustable averaging x Automatic response detection x Presentation of results Display of result x Display of PASS/REFER x Display of a quality measure x Documentation Display, internal/external storage, and export of test results/
35、parameters x 1 If a different test signal is used, it shall be described by the manufacturer. 2 Usually a white noise signal is used for contra-lateral masking. BS EN 60645-7:2010 8 60645-7 IEC:2009 5 General specifications 5.1 Measuring system 5.1.1 Units of measurement SI units or derived SI units
36、 shall be used. The units of measurement shall be indicated. 5.1.2 Measurement range The minimum measurement ranges for AEP shall be from 10 nV to 2 V for instruments of Type 1. 5.1.3 Time resolution The time resolution shall be 0,1 ms or better for instruments of Type 1. NOTE The minimum time resol
37、ution is determined by the sampling rate of the device. The amplitude accuracy limit is given by the internal noise. 5.2 Stimulus system 5.2.1 General requirements Specifications for the stimulus system are as given in the relevant parts of Clauses 6, 8 and 10 of IEC 60645-1:2001, and Clause 5 of IE
38、C 60645-3:2007 with the exceptions specified below. 5.2.2 Stimulus types 5.2.2.1 General The general properties and temporal characteristics of the stimulus signal are specified in IEC 60645-3. Other stimulus types shall be specified by the manufacturer, if applicable. 5.2.2.2 Masking signal The man
39、ufacturer shall provide the frequency characteristics and levels of the masking signal. 5.2.2.3 Stimulus levels For instruments of Type 1, stimulus levels shall cover a hearing level range of at least 30 dB to 80 dB. For instruments of Type 2, the stimulus level range shall be specified by the manuf
40、acturer. 5.3 Test quality assuring system 5.3.1 Recording conditions A facility for checking the test conditions shall be provided, for example, by checking the electrical impedance between the electrodes. The system shall be able to improve the initial signal-to-noise ratio by at least 30 dB in the
41、 relevant frequency range, for example, by an averaging procedure. An artefact rejection system shall be provided. BS EN 60645-7:201060645-7 IEC:2009 9 5.3.2 Response detection If an algorithm is used for automatic detection (mandatory for Type 2 instruments), its statistical significance shall be v
42、alidated by the manufacturer. 5.3.3 Quality estimates The efficiency of the method used for estimation of residual noise shall be documented by the manufacturer. 5.3.4 Reference values Reference hearing threshold values are given in the ISO 389 series. If other reference values are used, these data
43、shall be validated and documented by the manufacturer. 5.4 Presentation of results All relevant information concerning stimulus, recording conditions and results according to Table 2 shall be stored and be available on demand. The information shall be presented on display of the instrument and/or as
44、 paper printout. Table 2 Documentation of test conditions, parameters and results Type 1 Diagnostic/clinical 2 Screening Stimulus level x x Contra-lateral masking x Test conditions1x Number of rejected and accepted records x Artefact rejection limit x Graphic display of full result x Display of PASS
45、/REFER x Test quality x 1 For example, artefacts during test, EEG level, electrode impedance, etc. 6 Demonstration of conformity with specifications 6.1 General The following procedures shall be used for ensuring that an instrument meets the specifications given in this part of IEC 60645. 6.2 Signal
46、-to-noise ratio improvement The improvement of the signal-to-noise ratio by at least 30 dB in the relevant frequency range shall be verified by a suitable procedure as specified by the manufacturer. 6.3 Maximum permitted expanded uncertainty of measurements UmaxTable 3 specifies the maximum permitte
47、d expanded uncertainty Umaxcalculated with a coverage factor of k = 2 to give a level of confidence of approximately 95 %, associated with the measurements undertaken in this part of IEC 60645, according to ISO/IEC Guide 98-3. One set of values for Umaxis given for basic type approval measurements.
48、BS EN 60645-7:2010 10 60645-7 IEC:2009 The expanded uncertainties of measurements given in Table 3 are the maximum permitted for demonstration of conformance to the requirements of this standard. If the actual expanded uncertainty of a measurement performed by the test laboratory exceeds the maximum
49、 permitted value in Table 3, the measurement shall not be used to demonstrate conformance to the requirements of this part of IEC 60645. Table 3 Values of Umaxfor basic measurements Measured quantity Relevant subclause number Basic Umax(k = 2) Measurement range 5.1.2 3 nV Time resolution 5.1.3 0,03 ms Stimulus levels 5.2.2.3 1,0 dB Signal-to-noise ratio 5.3.1 1,0 dB Temperature 7.5.3 0,5 C Relative humidity 7.5.3 5 % Ambient pressure 7.5.3 0,1 kPa 7 General re
