SIST HD 450.3 S1:2004

SLOVENSKI STANDARD
SIST HD 450.3 S1:2004
01-januar-2004
[Not translated]
Hearing aids - Part 3: Hearing aid equipment not entirely worn on the listener
Hörgeräte - Teil 3: Hörhilfen-Systeme, die nur zum Teil vom Benutzer getragen werden
Appareils de correction auditive - Partie 3: Systèmes de correction auditive non
entièrement portés par l'auditeur
Ta slovenski standard je istoveten z: HD 450.3 S1:1984
ICS:
11.180.15 3ULSRPRþNL]DJOXKHRVHEHLQ Aids for deaf and hearing
RVHEH]RNYDURVOXKD impaired people
SIST HD 450.3 S1:2004 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST HD 450.3 S1:2004

NORME CEI


INTERNATIONALE IEC



60118-3
INTERNATIONAL

Deuxième édition

STAN DARD
Second edition

1983-01




Appareils de correction auditive
Troisième partie:
Systèmes de correction auditive non entièrement
portés par l'auditor
Hearing aids
Part 3:
Hearing aid equipment not entirely worn
on the listener

© IEC 1983 Droits de reproduction réservés — Copyright - all rights reserved
Aucune partie de cette publication ne peut être reproduite ni No part of this publication may be reproduced or utilized in
utilisée sous quelque forme que ce soit et par aucun any form or by any means, electronic or mechanical,
procédé, électronique ou mécanique, y compris la photo- including photocopying and microfilm, without permission in
copie et les microfilms, sans l'accord écrit de l'éditeur. writing from the publisher.
International Electrotechnical Commission 3, rue de Varembé Geneva, Switzerland
Telefax: +41 22 919 0300 e-mail: inmail@iec.ch IEC web site http: //www.iec.ch
CODE PRIX
Commission Electrotechnique Internationale
G
PRICE CODE
International Electrotechnical Commission
IEC McHSAyHaponHaR 3fleNTpoTexHwiecKaR HOMNCCNfi
Pour prix, voir catalogue en vigueur
• • For price, see current catalogue

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INTERNATIONAL ELECTROTECHNICAL COMMISSION




HEARING AIDS


Part 3: Hearing aid equipment not entirely worn on the listener




FOREWORD
1) The formal decisions or agreements of the IEC on technical matters, prepared by Technical Committees on which all the
National Committees having a special interest therein are represented, express, as nearly as possible, an international
consensus of opinion on the subjects dealt with.
2) They have the form of recommendations for international use and they are accepted by the National Committees in that
sense.
3) In order to promote international unification, the IEC expresses the wish that all National Committees should adopt the text
of the IEC recommendation for their national rules in so far as national conditions will permit. Any divergence between the
IEC recommendation and the corresponding national rules should, as far as possible, be clearly indicated in the latter.
PREFACE TO THE FIRST EDITION
This standard has been prepared by IEC Technical Committee No.29: Electroacoustics.
The first draft was discussed at the meeting held in Gaithersburg in 1976. As a result of this meeting, a draft, Document
29(Central Office)108, was submitted to the National Committees for approval under the Six Months' Rule in June 1977.
The following countries voted explicitly in favour of publication:
Austria Germany Spain
Sweden
Belgium Japan
Brazil Netherlands Switzerland
Czechoslovakia Norway Turkey
Denmark United Kingdom
Poland
Egypt Romania United States of America
France South Africa (Republic of)
PREFACE TO THE SECOND EDITION
This second edition comprises the first edition, issued in 1979, and editorial amendments which are due to the issuing of IEC
Publication 118-0 (1983).

Other IEC publications quoted in this standard:
Publications Nos. 65: Safety Requirements for Mains Operated Electronic and Related Apparatus for Household and
Similar General Use.
118-0: Hearing Aids, Part 0: Measurement of Electroacoustical Characteristics.
268-3: Sound System Equipment, Part 3: Sound System Amplifiers.
268-4: Sound System Equipment, Part 4: Microphones.
303: IEC Provisional Reference Coupler for the Calibration of Earphones Used in Audiometry.
318: An IEC Artificial Ear, of the Wideband Type, for the Calibration of Earphones Used in
Audiometry.
711: Occluded-ear Simulator for the Measurement of Earphones Coupled to the Ear by Ear Inserts.

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118-3 © IEC 1983 5



HEARING AIDS


Part 3: Hearing aid equipment not entirely worn on the listener








INTRODUCTION
In the rehabilitation of persons having impaired hearing, use is made of two types of electroacoustic
amplification systems:
a) Hearing aids entirely worn on the listener.
b)
Hearing aid equipment in which the microphone or microphones are not worn on the listener.
IEC Publication 118-0: Hearing Aids, Part 0: Measurement of Electroacoustical Characteristics, gives
details of methods of measurements on hearing aids and in general covers the requirements for other hearing
aid equipment.
However, measurements on hearing aid equipment involve certain test differences which are detailed in
this standard. Reference is made wherever possible to IEC Publication 268: Sound System Equipment, for
measurements not covered in IEC Publication 118-0.
1. Scope
The purpose of this standard is to describe a method of determining the overall electroacoustic
performance of hearing aid equipment not entirely worn on the listener, used in the rehabilitation of
persons having impaired hearing.
2. Object

The methods specified in this publication give information on the measurement of those parameters
that are not fully covered in IEC Publication 118-0; i.e.:
Frequency response.
Air to air gain.
Acoustic output.
Gain and output controls.
Internal noise of the equipment.
Electrical input sensitivity and output power.
Overall effect of transmission paths in systems where the microphone(s) is (are) not connected by
wire to the earphone(s).
Measurements other than the above are specified in IEC publications, for example IEC Publication
118-0 and IEC Publication 268.

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3. Test equipment


3.1 General


Throughout this standard, all sound pressure levels specified are referred to 20 µPa. All voltage level

measurements are referred to 1 V. All results can be given as r.m.s. values.



Note.– With non-sinusoidal signals appreciable measuring errors can arise when using instruments which measure mean
values but are calibrated in r.m.s. terms.


3.2 Acoustic requirements for testing microphones


The microphone shall be placed in an acoustic test field in accordance with IEC Publication 268-4:
Part 4: Microphones, under the stated conditions appropriate to the microphone used and connected to
the amplifying system. Where the microphone is separate from the amplifier, only the microphone shall
be placed in the acoustic test field. Where the microphone is an integral part of a main unit, the whole
unit shall be placed in the sound field.
The method of measurement shall be described in the test report.
3.3 Acoustic couplers
IEC Publication 318: An IEC Artificial Ear, of the Wideband Type, for the Calibration of
Earphones Used in Audiometry, describes the preferred device for measuring the acoustic output of
supra-aural earphones.
IEC Publication 303: IEC Provisional Reference Coupler for the Calibration of Earphones Used in
Audiometry, describes an acoustic coupler for supra-aural earphones which may be used if a device
conforming to IEC Publication 318 is not available.
Note. – Until specifications are available for an agreed method and device for measuring the performance of ci
...