Acoustics - Audiometric test methods - Part 1: Pure-tone air and bone conduction audiometry (ISO 8253-1:2010)

This part of ISO 8253 specifies procedures and requirements for pure-tone air conduction and bone conduction threshold audiometry. For screening purposes, only pure-tone air conduction audiometric test methods are specified. It is possible that the procedures are not appropriate for special populations, e.g. very young children. This part of ISO 8253 does not cover audiometric procedures to be carried out at levels above the hearing threshold levels of the subjects. Procedures and requirements for speech audiometry, electrophysiological audiometry, and where loudspeakers are used as a sound source are not specified.

Akustik - Audiometrische Prüfverfahren - Teil 1: Grundlegende Verfahren der Luft- und Knochenleitungs-Schwellenaudiometrie mit reinen Tönen (ISO 8253-1:2010)

Dieser Teil von ISO 8253 legt Verfahren und Anforderungen für Luft- und Knochenleitungs-Reinton-
Schwellenaudiometrie fest. Für audiometrische Screening-Tests werden nur Reinton-Luftleitungs-Verfahren
beschrieben. Die Verfahren sind möglicherweise für besondere Gruppen, z. B. sehr junge Kinder, nicht
geeignet.
Audiometrische Verfahren, die bei Pegeln über der Hörschwelle der Probanden durchgeführt werden, sind
nicht Gegenstand dieses Teils von ISO 8253.
Verfahren und Anforderungen für die Sprachaudiometrie, elektrophysiologische Audiometrie und Verfahren,
bei denen Lautsprecher als Schallquellen eingesetzt werden, werden nicht festgelegt.

Acoustique - Méthodes d'essais audiométriques - Partie 1: Audiométrie à sons purs en conduction aérienne et en conduction osseuse (ISO 8253-1:2010)

L'ISO 8253-1:2010 spécifie des modes opératoires et des exigences relatives à l'audiométrie liminaire à sons purs en conduction aérienne et en conduction osseuse. En ce qui concerne l'audiométrie de dépistage, seules sont décrites des méthodes audiométriques liminaires tonales en conduction aérienne. Il est possible que les modes opératoires ne conviennent pas à certaines populations, par exemple aux très jeunes enfants.
L'ISO 8253-1:2010 ne traite pas des méthodes audiométriques devant être exécutées à des niveaux dépassant les niveaux liminaires d'audition des sujets testés.
Les modes opératoires et les exigences relatifs à l'audiométrie vocale, à l'audiométrie électrophysiologique et à l'usage de haut-parleurs pour délivrer les sons ne sont pas spécifiés.

Akustika - Avdiometrijske preskusne metode - 1. del: Avdiometrija s čistimi toni za zračno in kostno prevodnost (ISO 8253-1:2010)

Ta del ISO 8253 opredeljuje postopke in zahteve za avdiometrijo s čistimi toni za zračno prevodnost in avdiometrijo pragovnih vrednosti za kostno prevodnost. Za presajanje so opredeljene le metode avdiometrije s čistimi zvoki za zračno prevodnost. Mogoče je, da ti postopki niso primerni za vse prebivalce, npr. zelo majhne otroke. Ta del ISO 8253 ne zajema postopkov avdiometrije, ki se izvajajo na ravneh nad slišnim pragom oseb. Postopki in zahteve za avdiometrijo govora, elektrofiziološko avdiometrijo in pri uporabi zvočnika kot vira hrupa niso opredeljeni.

General Information

Status
Published
Public Enquiry End Date
14-Dec-2008
Publication Date
03-Feb-2011
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
30-Nov-2010
Due Date
04-Feb-2011
Completion Date
04-Feb-2011

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Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 8253-1:2011
01-marec-2011
1DGRPHãþD
SIST EN 26189:1999
SIST EN ISO 8253-1:1999
$NXVWLND$YGLRPHWULMVNHSUHVNXVQHPHWRGHGHO$YGLRPHWULMDVþLVWLPLWRQL]D
]UDþQRLQNRVWQRSUHYRGQRVW ,62
Acoustics - Audiometric test methods - Part 1: Pure-tone air and bone conduction
audiometry (ISO 8253-1:2010)
Akustik - Audiometrische Prüfverfahren - Teil 1: Grundlegende Verfahren der Luft- und
Knochenleitungs-Schwellenaudiometrie mit reinen Tönen (ISO 8253-1:2010)
Acoustique - Méthodes d'essais audiométriques - Partie 1: Audiométrie à sons purs en
conduction aérienne et en conduction osseuse (ISO 8253-1:2010)
Ta slovenski standard je istoveten z: EN ISO 8253-1:2010
ICS:
13.140 Vpliv hrupa na ljudi Noise with respect to human
beings
17.140.01 $NXVWLþQDPHUMHQMDLQ Acoustic measurements and
EODåHQMHKUXSDQDVSORãQR noise abatement in general
SIST EN ISO 8253-1:2011 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 8253-1:2011

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SIST EN ISO 8253-1:2011


EUROPEAN STANDARD
EN ISO 8253-1

NORME EUROPÉENNE

EUROPÄISCHE NORM
November 2010
ICS 13.140 Supersedes EN 26189:1991, EN ISO 8253-1:1998
English Version
Acoustics - Audiometric test methods - Part 1: Pure-tone air and
bone conduction audiometry (ISO 8253-1:2010)
Acoustique - Méthodes d'essais audiométriques - Partie 1: Akustik - Audiometrische Prüfverfahren - Teil 1:
Audiométrie à sons purs en conduction aérienne et en Grundlegende Verfahren der Luft- und Knochenleitungs-
conduction osseuse (ISO 8253-1:2010) Schwellenaudiometrie mit reinen Tönen (ISO 8253-1:2010)
This European Standard was approved by CEN on 25 September 2010.

CEN 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 obtained on application to the CEN-CENELEC Management Centre or to any CEN 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 CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same
status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, 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 United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2010 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 8253-1:2010: E
worldwide for CEN national Members.

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SIST EN ISO 8253-1:2011
EN ISO 8253-1:2010 (E)
Contents Page
Foreword .3

2

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SIST EN ISO 8253-1:2011
EN ISO 8253-1:2010 (E)
Foreword
This document (EN ISO 8253-1:2010) has been prepared by Technical Committee ISO/TC 43 “Acoustics” in
collaboration with 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 publication of an identical
text or by endorsement, at the latest by May 2011, and conflicting national standards shall be withdrawn at the
latest by May 2011.
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 be held responsible for identifying any or all such patent rights.
This document supersedes EN 26189:1991 and EN ISO 8253-1:1998.
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, Croatia, 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 ISO 8253-1:2010 has been approved by CEN as a EN ISO 8253-1:2010 without any modification.

3

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SIST EN ISO 8253-1:2011

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SIST EN ISO 8253-1:2011

INTERNATIONAL ISO
STANDARD 8253-1
Second edition
2010-11-01

Acoustics — Audiometric test methods —
Part 1:
Pure-tone air and bone conduction
audiometry
Acoustique — Méthodes d'essais audiométriques —
Partie 1: Audiométrie à sons purs en conduction aérienne et en
conduction osseuse




Reference number
ISO 8253-1:2010(E)
©
ISO 2010

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SIST EN ISO 8253-1:2011
ISO 8253-1:2010(E)
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All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
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Published in Switzerland

ii © ISO 2010 – All rights reserved

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SIST EN ISO 8253-1:2011
ISO 8253-1:2010(E)
Contents Page
Foreword .v
Introduction.vi
1 Scope.1
2 Normative references.1
3 Terms and definitions .2
4 General aspects of audiometric measurements .4
4.1 General .4
4.2 Standard reference zero for the calibration of audiometric equipment .5
4.3 Requirements on audiometric equipment .5
4.4 Qualified tester .5
4.5 Test time.5
4.6 Conditions for audiometric test environments .5
4.7 Measurement uncertainty.6
5 Preparation and instruction of test subjects before audiometric testing and positioning of
transducers .6
5.1 Preparation of test subjects .6
5.2 Instruction of test subjects.7
5.3 Placement of transducers .7
6 Air conduction hearing threshold level determinations using fixed-frequency audiometry .7
6.1 General .7
6.2 Manually controlled threshold determination .8
6.3 Hearing threshold determination with an automatic recording audiometer.10
6.4 Computer-controlled threshold determination.12
7 Air conduction hearing threshold level determinations using sweep-frequency
audiometry .12
7.1 General .12
7.2 Presentation of test tone .12
7.3 Familiarization .12
7.4 Hearing threshold level measurement .12
7.5 Calculation of hearing threshold level at a specified frequency.12
8 Bone conduction hearing threshold audiometry .13
8.1 Method of audiometry.13
8.2 Occlusion .13
8.3 Airborne sound radiation from the bone vibrator.13
8.4 Vibrotactile sensation .13
8.5 Procedures for testing with masking in bone conduction audiometry .13
9 Screening audiometry.14
9.1 General .14
9.2 Procedure for the screening test .14
10 Audiograms.15
11 Permissible ambient noise .16
11.1 Permissible ambient noise for threshold determinations.16
11.2 Psycho-acoustic check on ambient noise.16
12 Maintenance and calibration of audiometric equipment.20
12.1 General .20
12.2 Intervals between checks .20
© ISO 2010 – All rights reserved iii

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SIST EN ISO 8253-1:2011
ISO 8253-1:2010(E)
12.3 Stage A — Routine checking and subjective tests . 20
12.4 Stage B — Periodic objective checks. 21
12.5 Stage C — Basic calibration tests. 22
Annex A (informative) Measurement uncertainty . 23
Bibliography. 28

iv © ISO 2010 – All rights reserved

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SIST EN ISO 8253-1:2011
ISO 8253-1:2010(E)
Foreword
ISO (the International Organization 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 has 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.
International 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. Publication 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 rights.
ISO 8253-1 was prepared by Technical Committee ISO/TC 43, Acoustics.
This second edition cancels and replaces the first edition (ISO 8253-1:1989) and ISO 6189:1983, which have
been technically revised.
ISO 8253 consists of the following parts, under the general title Acoustics — Audiometric test methods:
⎯ Part 1: Pure-tone air and bone conduction audiometry
⎯ Part 2: Sound field audiometry with pure-tone and narrow-band test signals
⎯ Part 3: Speech audiometry
© ISO 2010 – All rights reserved v

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SIST EN ISO 8253-1:2011
ISO 8253-1:2010(E)
Introduction
This International Standard specifies requirements and procedures for carrying out basic audiometric tests in
which pure tones are presented to the test subject using earphones or bone vibrators. Electrophysiological
test methods are not included.
In order to obtain a reliable measure of hearing ability, many factors are involved. IEC 60645-1 specifies
requirements for audiometers. It is essential that audiometric equipment, when in service, be checked and the
calibration maintained. This part of ISO 8253 outlines a calibration scheme. To avoid masking of the test
signal by ambient noise in the audiometric test room, the levels of the ambient noise shall not exceed certain
values, depending upon the method of signal presentation to the test subject, i.e. by different earphones or by
bone vibrator. This part of ISO 8253 gives maximum permissible ambient sound pressure levels which shall
not be exceeded when hearing threshold levels down to 0 dB have to be measured. It indicates the maximum
ambient sound pressure levels which are permissible when other minimum hearing threshold levels require
measurement. It sets out procedures for determining hearing threshold levels by pure-tone air conduction and
bone conduction audiometry. For screening purposes, only methods for air conduction audiometry are
outlined.
Audiometry can be performed by using:
a) a manual audiometer;
b) an automatic recording audiometer;
c) computer-controlled audiometric equipment.
Methods for threshold audiometry are given for these three types of signal presentation. For screening
purposes, only methods using a manual or a computer-controlled audiometer are set out. The procedures are
applicable to the majority of adults and children. Other procedures may yield results equivalent to those
derived by the procedures specified in this part of ISO 8253. For very young, aged or sick people, some
modification of the recommended procedures is likely to be required. This may result in a less accurate
measurement of hearing.

vi © ISO 2010 – All rights reserved

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SIST EN ISO 8253-1:2011
INTERNATIONAL STANDARD ISO 8253-1:2010(E)

Acoustics — Audiometric test methods —
Part 1:
Pure-tone air and bone conduction audiometry
1 Scope
This part of ISO 8253 specifies procedures and requirements for pure-tone air conduction and bone
conduction threshold audiometry. For screening purposes, only pure-tone air conduction audiometric test
methods are specified. It is possible that the procedures are not appropriate for special populations, e.g. very
young children.
This part of ISO 8253 does not cover audiometric procedures to be carried out at levels above the hearing
threshold levels of the subjects.
Procedures and requirements for speech audiometry, electrophysiological audiometry, and where
loudspeakers are used as a sound source are not specified.
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.
ISO 389-1, Acoustics — Reference zero for the calibration of audiometric equipment — Part 1: Reference
equivalent threshold sound pressure levels for pure tones and supra-aural earphones
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
ISO 389-3:1994, Acoustics — Reference zero for the calibration of audiometric equipment — Part 3:
Reference equivalent threshold force levels for pure tones and bone vibrators
ISO 389-5, Acoustics — Reference zero for the calibration of audiometric equipment — Part 5: Reference
equivalent threshold sound pressure levels for pure tones in the frequency range 8 kHz to 16 kHz
ISO 389-8, Acoustics — Reference zero for the calibration of audiometric equipment — Part 8: Reference
equivalent threshold sound pressure levels for pure tones and circumaural earphones
IEC 60645-1:2001, Electroacoustics — Audiological equipment — Part 1: Pure-tone audiometers
IEC 61260, Electroacoustics — Octave-band and fractional-octave-band filters
IEC 61672-1, Electroacoustics — Sound level meters — Part 1: Specifications
ISO/IEC Guide 98-3, Uncertainty of measurement — Part 3: Guide to the expression of uncertainty in
measurement (GUM:1995)
© ISO 2010 – All rights reserved 1

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SIST EN ISO 8253-1:2011
ISO 8253-1:2010(E)
3 Terms and definitions
For the purposes of this part of ISO 8253, the following definitions apply.
3.1
air conduction
transmission of sound through the external and middle ear to the inner ear
3.2
ear simulator
device for measuring the acoustic output of sound sources where the sound pressure is measured by a
calibrated microphone coupled to the source so that the overall acoustic impedance of the device
approximates that of the normal human ear at a given location and in a given frequency band
[4] [6]
NOTE An ear simulator is specified in IEC 60318-1 and IEC 60318-4 .
3.3
acoustic coupler
device for measuring the acoustic output of sound sources where the sound pressure is measured by a
calibrated microphone coupled to the source by a cavity of predetermined shape and volume which does not
necessarily approximate the acoustic impedance of the normal human ear
[5] [7]
NOTE An acoustic coupler is specified in IEC 60318-3 and IEC 60318-5 .
3.4
bone conduction
transmission of sound to the inner ear primarily by means of mechanical vibration of the cranial bones
3.5
bone vibrator
electromechanical transducer intended to produce the sensation of hearing by vibrating the cranial bones
3.6
mechanical coupler
device designed to present a specified mechanical impedance to a vibrator applied with a specified static
force and equipped with a mechano-electrical transducer to measure the vibratory force level at the surface of
contact between vibrator and mechanical coupler
[8]
NOTE A mechanical coupler is specified in IEC 60318-6 .
3.7
otologically normal person
person in a normal state of health who is free from all signs and symptoms 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 familial hearing loss
3.8
hearing threshold
lowest sound pressure level or vibratory force level at which, under specified conditions, a person gives a
predetermined percentage of correct detection responses on repeated trials
3.9
equivalent threshold sound pressure level
for a given ear, at a specified frequency, for a specified type of earphone and for a stated force of application
of the earphone to the human ear, the sound pressure level set up by the earphone in a specified acoustic
coupler or ear simulator when the earphone is actuated by that voltage which, with the earphone applied to
the ear concerned, would correspond to the hearing threshold
2 © ISO 2010 – All rights reserved

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SIST EN ISO 8253-1:2011
ISO 8253-1:2010(E)
3.10
reference equivalent threshold sound pressure level
RETSPL
at a specified frequency, the median value of the equivalent threshold sound pressure levels of a sufficiently
large number of ears of otologically normal persons of both sexes aged from 18 years to 25 years inclusive,
expressing the hearing threshold in a specified acoustic coupler or ear simulator for a specified type of
earphone
NOTE ISO 389-1 refers to an age range of 18 years to 30 years inclusive, and specifies modal values.
3.11
equivalent threshold vibratory force level
for a given ear, at a specified frequency, for a specified configuration of bone vibrator and for a stated force of
application of the bone vibrator to the human mastoid or forehead, the vibratory force level set up by the bone
vibrator on a specified mechanical coupler when the bone vibrator is actuated by that voltage which, with the
bone vibrator applied to the mastoid or forehead concerned, would correspond to the hearing threshold
3.12
reference equivalent threshold vibratory force level
RETVFL
at a specified frequency, the median value of the equivalent threshold vibratory force levels of a sufficiently
large number of ears of otologically normal persons of both sexes aged from 18 years to 25 years inclusive,
expressing the hearing threshold in a specified mechanical coupler for a specified type of bone vibrator
NOTE ISO 389-3 refers to an age range of 18 years to 30 years inclusive, and specifies an arithmetic mean.
3.13
hearing level of a pure tone
HL of a pure tone
at a specified frequency, for a specific type of transducer and for a specified manner of application, sound
pressure level or vibratory force level of a pure tone, produced by a transducer in a specific ear simulator or
mechanical coupler, minus the appropriate reference equivalent threshold sound pressure level or reference
equivalent threshold vibratory force level
3.14
hearing threshold level of a given ear
at a specified frequency and for a specific type of transducer, hearing threshold at that frequency, expressed
as hearing level
3.15
occlusion effect
change (usually an increase) in level of a bone-conducted signal reaching the inner ear when an earphone or
an earplug is placed over or at the entrance of the ear canal, thereby forming an enclosed air volume in the
external ear
NOTE The effect is greatest at low frequencies.
3.16
masking
process by which the hearing threshold of a given ear for a particular sound is raised by the presence of
another (masking) sound
3.17
effective masking level of a noise band
level equal to that hearing level of a pure tone, the frequency of which coincides with the geometric centre
frequency of the noise band, to which the threshold of hearing of the pure tone is raised by the presence of
the masking noise band
NOTE IEC 60645-1:2001, 8.5.2 a), specifies that masking levels for narrow-band noise be calibrated in terms of
effective masking level.
© ISO 2010 – All rights reserved 3

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SIST EN ISO 8253-1:2011
ISO 8253-1:2010(E)
3.18
vibrotactile threshold level
level of the vibratory force or sound pressure at which a person gives 50 % of correct detection responses on
repeated trials due to the sensation of vibration on the skin
3.19
pure-tone audiometer
electroacoustic instrument, equipped with earphone(s), that provides pure tones of specified frequencies at
known sound pressure levels
NOTE In addition, it may be equipped with bone vibrator(s) and/or masking facilities.
3.20
manual audiometer
audiometer in which the signal presentations, frequency and hearing level selection and recording of the
results are performed manually
3.21
automatic-recording audiometer
audiometer in which signal presentations, hearing level variation, frequency selection or frequency variation,
and recording of the responses of the test subject are implemented automatically
NOTE Hearing level change is under the control of the test subject and is recorded automatically.
3.22
automatic fixed-frequency audiometry
audiometry in which hearing level variations are under the control of the test subject and are recorded
automatically for specific frequencies
3.23
automatic sweep-frequency audiometry
audiometry in which hearing level variations are under the control of the test subject and where the frequency
is varied continuously or in steps much smaller than one-third octave
3.24
screening audiometry
pass-fail procedure where pure tones of a fixed level, the screening level, are presented
3.25
audiogram
presentation, in graphical or tabular form, of the hearing threshold levels of the ears of the test subject,
determined under specified conditions and by a specified method, as a function of frequency
4 General aspects of audiometric measurements
4.1 General
Hearing threshold levels can be determined by air conduction and bone conduction audiometry. In air
conduction audiometry, the test signal is presented to the test subject by earphones. In bone conduction
audiometry, the test signal is presented by a bone vibrator placed on the mastoid or forehead of the test
subject. It is recommended that threshold level determinations be started with air conduction measurements
followed by bone conduction measurements. Hearing threshold levels can be determined using test tones with
fixed frequencies (fixed-frequency audiometry) or a test signal with frequency varying with time according to a
predetermined rate of change (sweep-frequency audiometry). Methods for fixed-frequency audiometry are
given in Clause 6 and sweep-frequency audiometry is described in Clause 7. In air and bone conduction
measurements, the hearing threshold levels of both ears shall be determined separately. Under specified
conditions, masking noise shall be applied to the ear not under test (contralateral ear). The masking noise is
presented to that ear through a supra-aural, circumaural or insert-type earphone.
4 © ISO
...

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