IEC 62489-2:2014

IEC 62489-2 ®
Edition 2.0 2014-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Electroacoustics – Audio-frequency induction loop systems for assisted
hearing –
Part 2: Methods of calculating and measuring the low-frequency magnetic field
emissions from the loop for assessing conformity with guidelines on limits for
human exposure
Électroacoustique – Systèmes de boucles d’induction audiofréquences pour
améliorer l'audition –
Partie 2: Méthodes de calcul et de mesure des émissions de champ magnétique
basse fréquence à partir de la boucle pour l’évaluation de la conformité aux
instructions sur les limites d’exposition humaine

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IEC 62489-2 ®
Edition 2.0 2014-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Electroacoustics – Audio-frequency induction loop systems for assisted

hearing –
Part 2: Methods of calculating and measuring the low-frequency magnetic field

emissions from the loop for assessing conformity with guidelines on limits for

human exposure
Électroacoustique – Systèmes de boucles d’induction audiofréquences pour

améliorer l'audition –
Partie 2: Méthodes de calcul et de mesure des émissions de champ magnétique

basse fréquence à partir de la boucle pour l’évaluation de la conformité aux

instructions sur les limites d’exposition humaine

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX P
ICS 17.140.50 ISBN 978-2-8322-1860-0

– 2 – IEC 62489-2:2014 © IEC 2014
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Rated values . 6
4 Situation regarding current standards . 6
5 Configurations of loops . 7
5.1 Main types of configuration . 7
5.2 General considerations . 7
5.3 Large-area loops . 7
5.4 Medium-area loops . 7
5.5 Small-area loops . 8
5.6 Solenoid antennas . 8
6 Calculations . 8
6.1 General . 8
6.2 Solenoid antennas . 9
7 Measurements . 9
7.1 General . 9
7.2 Input signal . 9
7.3 Measuring instrument. 9
8 Comparison of calculated or measured results with guidelines or limits . 10
9 Meeting limits or guidelines . 10
10 Measurement uncertainty . 10
Annex A (informative) Rationale for this product-family magnetic field emission
standard for audio-frequency induction-loop systems (AFILS) in the context of human
exposure to non-ionizing radiation . 11
Bibliography . 14

Figure 1 – An ear-hook induction transducer, with a BTE (behind the ear) hearing aid
body for scale . 8
Figure A.1 – ICNIRP magnetic field reference levels . 11

Table 1 – Basic restrictions . 10
Table A.1 – Application to AFILS of Table 1 of IEC 62311:2007 "Characteristics and
parameters of the equipment to be considered" . 12

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTROACOUSTICS –
AUDIO-FREQUENCY INDUCTION
LOOP SYSTEMS FOR ASSISTED HEARING –

Part 2: Methods of calculating and measuring the low-frequency
magnetic field emissions from the loop for assessing conformity
with guidelines on limits for human exposure

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
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5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
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6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62489-2 has been prepared by IEC technical committee 29:
Electroacoustics.
This second edition cancels and replaces the first edition published in 2011. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition: it reflects several updates to the ICNIRP Guide [1] to which it makes frequent
________________
Numbers in square brackets refer to the Bibliography.

– 4 – IEC 62489-2:2014 © IEC 2014
reference. The most significant change is that the underlying metric in the Guide has been
changed from tissue current density to induced electric field.
The text of this standard is based on the following documents:
FDIS Report on voting
29/847/FDIS 29/854/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of the IEC 62489 series, published under the general title Electroacoustics –
Audio-frequency induction loop systems for assisted hearing, can be found on the IEC
website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
INTRODUCTION
A revision of IEC 62489-2 is necessary because, while the standard does not call up any
particular set of exposure limits, it has numerous references to the ICNIRP Guide, which has
profoundly changed between the 1998 and 2010 editions. This has resulted in a change in the
physical quantity on which the basic restrictions are established, from tissue current density to
induced electric field, resulting in changes to the reference levels and a considerable
simplification of the application of the guidelines.
The recommendations of the new Guide have not yet been adopted at the regulatory level in
the European Union. However, since the references to the Guide in IEC 62489-2 are purely
informative, it does not appear that this revision should be unacceptable in Europe.

– 6 – IEC 62489-2:2014 © IEC 2014
ELECTROACOUSTICS –
AUDIO-FREQUENCY INDUCTION
LOOP SYSTEMS FOR ASSISTED HEARING –

Part 2: Methods of calculating and measuring the low-frequency
magnetic field emissions from the loop for assessing conformity
with guidelines on limits for human exposure

1 Scope
This part of IEC 62489 applies to audio-frequency induction-loop systems for assisted
hearing. It may also be applied to such systems used for other purposes, as far as it is
applicable. The standard is intended for assessment of human exposure to low-frequency
magnetic fields produced by the system, by calculation and by in-situ testing.
This standard does not deal with other aspects of safety, for which IEC 60065 applies, or with
EMC.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60118-4:2006, Electroacoustics - Hearing aids - Part 4: Induction loop systems for
hearing aid purposes - Magnetic field strength
IEC 60268-1:1985, Sound system equipment – Part 1: General
IEC 60268-2:1987, Sound system equipment – Part 2: Explanation of general terms and
calculation methods
IEC 60268-10:1991, Sound system equipment – Part 10: Peak programme level meters
3 Rated values
The term "rated" means "the value stated by the manufacturer". Rated values are of two
kinds: rated conditions, which are fundamental values that cannot be verified by
measurement, and others that can be so verified. For a full explanation, see IEC 60268-2.
4 Situation regarding current standards
Current published and draft IEC standards on EMF exposure can be ambiguous in their
guidance on the approach that should be taken by product committees. The differences
between the signals that are of concern and those considered in depth in EMF exposure
standards are the following:
• wide relative bandwidth, i.e. the ratio of highest to lowest frequency present, 5 kHz and
100 Hz;
• no predominant frequency within the band;

• rapidly varying amplitude;
• high ratio of peak amplitude to average r.m.s. amplitude (at least 4).
5 Configurations of loops
5.1 Main types of configuration
There are four main types of configuration:
a) large area loops, with the smallest dimension larger than 1 m, usually installed at floor
level in a room;
b) medium-area loops, with dimensions of the order of 1 m, often oriented in a vertical plane,
installed at service desks and similar positions;
c) small area loops, with the largest dimension less than 1 m;
d) solenoid antennas, including the ear-hook.
NOTE Examples of small-area loops are portable systems, clipboards, neck loops, cushion loops (including those
for use in vehicles) and chair loops.
5.2 General considerations
All loops produce strong fields close to the loop conductor(s). This is shown by the
relationship between current I in a long, straight wire and the magnetic field strength H
produced at a distance R from the centre of the wire, where R is greater than the radius r of
the wire:
H = I/2πR (1)
NOTE 1 Within the wire, the field strength decreases linearly from I/2πr at the surface to zero at the centre.
NOTE 2 For n parallel conductors very close together (i.e. a multi-turn loop), the magnetic field strength is n times
that produced by a single conductor.
For calculations of field strengths in the high field strength regions, very close to the
conductor(s), the 'long, straight wire' approximation is almost always sufficiently accurate,
except for solenoids, which need a completely different treatment (see 6.2).
5.3 Large-area loops
The occupants of a room are likely to come close to the loop conductor only by stepping on
the floor at a point below which the conductor is installed. Such proximity is normally
transient. However, in places of worship, devotional postures can bring parts of the body
other than the feet into proximity. This can also apply in hospitals, treatment rooms and
gymnasia.
Maintenance staff might come into closer contact and for longer periods, but it is unlikely that
the system would then be operating.
5.4 Medium-area loops
For these, there are three considerations.
a) The hearing-aid user is normally at a distance from the loop comparable to its dimensions.
Thus the loop current required to produce a maximum r.m.s. field strength of 400 mA/m (in
compliance with IEC 60118-4) at the hearing-aid is much larger than the current required
to produce it at the centre of the plane of the loop.
b) Nevertheless, the separation ensures that the hearing-aid user is not exposed to the high
fields strengths near the loop conductor.

– 8 – IEC 62489-2:2014 © IEC 2014
c) However, staff can come into close proximity of the loop conductor while the system is
working unless steps are taken to maintain a minimum separation.
NOTE These loops often have more than one turn, so that the loop current can be kept reasonably small.
5.5 Small-area loops
For these, again, there are three considerations.
a) The separation for portable loops is very much greater than the loop dimensions, but for
other types, the separation distance can be small or very small unless steps are taken to
maintain a minimum separation.
b) The current apparently required is quite large, because of the large separation.
c) Both users and staff can come into close proximity of the loop, even that of a portable
system.
NOTE These loops usually have many turns, so that the actual current is not so large.
5.6 Solenoid antennas
One example that is commercially available is the ear-hook. This device is typically as shown
in Figure 1. A very small solenoid is incorporated in the stem of the device.
IEC
Figure 1 – An ear-hook induction transducer, with
a BTE (behind the ear) hearing aid body for scale
6 Calculations
6.1 General
Calculation of the field strength can be reliably made using Equation (1) in almost all cases,
except where the loop is very small or is a solenoid of length which is not very small
compared with its plan dimensions, such as for the ear-hook device. It is necessary to
calculate the current required in the loop to produce a field strength of 400 mA/m at the
hearing-aid position, taking into account the orientation of the pick-up coil in the hearing-aid
relative to the plane of the loop. In general, this calculation is not easy, but simple,
approximate methods give sufficiently accurate results when used with insight. Proprietary
calculation software, based on published mathematical analyses, exists. General-purpose
mathematics software can also be used.
Translating the calculated field strengths into a form comparable with exposure guidelines or
limits is considered in Clause 8.

6.2 Solenoid antennas
There is no simple expression for the field strength at a point outside a cylindrical solenoid. A
solenoid may be treated as a stack of loops, or as a magnetic dipole, or the field strength can
be calculated by means of a rather complex equation (see [2]).
7 Measurements
7.1 General
In the audio-frequency range, exposure time is irrelevant, because the predominant
physiological effect, if it occurs, is nerve stimulation, which operates over a time-scale of a
few milliseconds. It is therefore appropriate to use a quasi-peak measurement of field
strength. Furthermore, exposure limits and guidelines are given in r.m.s. values, so the quasi-
peak meter should be scaled to read r.m.s. values with a sinusoidal signal. This type of meter,
the peak programme meter (PPM), is further described in IEC 60118-4 and IEC 60268-10
(type II) already.
It is also necessary to consider the type of magnetic field pick-up coil or sensor. Sensors may
be single-axis, with just one coil, or three-axis, with three orthogonal coils. For use with a
PPM, the single-axis sensor is most convenient, and if it is properly constructed, it is not
difficult to orient it for maximum reading, especially as the likely direction of the field can
usually be predicted from text-book field patterns.
The first measurement that shall be made is that the field strength is correct at the point or
points where it is intended to be 400 mA/m (or the agreed lower value if adjusted to reduce
loudness, as specified in IEC 60118-4).
NOTE IEC 60118-4 specifies the use of either a PPM or an r.m.s. meter with a 125 ms integration time for the
measurement of magnetic field strength. However, for the purpose of this standard, the 125 ms integration time is
incompatible with the requirement to measure field strengths over times of the order of a few milliseconds.
The instrument specified for measurements on other equipment and systems, such as in IEC 62233 [3], has an
averaging time specified only as an upper limit of 1 s, which is also too slow for the assessment of fields due to
audio-frequency signals.
7.2 Input signal
The input signal for the amplifier shall be the simulated programme signal described in
IEC 60268-1, with additional filtering, –3 dB at 100 Hz and 5 kHz relative to the 1 kHz level,
with ultimate attenuation slopes of at least 12 dB/octave.
7.3 Measuring instrument
It is unlikely that a suitable complete instrument is commercially available at present, since
the application is extremely specialized. However, the design of an adapter for use with
widely-available audio test equipment, or that itself provides the PPM function, is not very
difficult. The elements are the following.
• The pick-up coil, which, because the field strengths of interest are high, needs few turns
and no magnetic core material. Because the fields are highly inhomogeneous, the coil
should be of small dimensions to minimize averaging. A coil covering four faces of a 1 cm
cube of insulating material is convenient.
• A frequency-response correction circuit, which produces a constant output from a
magnetic field that varies with frequency in the same way as the guidelines or limits, with
bandwidth control so as to discard out-of band interference signals.
• Amplification of the signal such that the maximum permissible field strength produces an
output voltage of 0,775 V for connection to the audio test equipment.
• Optionally, a quasi-peak detector substantially as specified in IEC 60268-10 (type II) and
means to display its output with a resolution of 1 dB.

– 10 – IEC 62489-2:2014 © IEC 2014
8 Comparison of calculated or measured results with guidelines or limits
The basic restrictions are based on the induced electric field. Table 1 gives the values for the
100 Hz to 5 kHz frequency range of audio-frequency induction-loop systems, where the head
is exposed to the magnetic field.
Table 1 – Basic restrictions
Frequency (f) Internal electric field strength
Hz mV/m
Occupational General public
100 to 400 2f –
100 to 1 000 – 0,4f
400 to 3 000 800 –
1 000 to 3 000 – 400
3 000 to 5 000 0,27f 0,135f
The reference levels for exposure to magnetic fields given in the ICNIRP Guide are based on
conversion factors between electric field strength and magnetic flux density established by
research. They are shown in Figure A.1.
9 Meeting limits or guidelines
The field strength near the loop conductor is fixed by the current, which in turn is fixed by the
field strength required at the hearing-aid position. It is clearly not possible to meet exposure
requirements by reducing the current. It is also obvious that any form of shielding is unlikely
to be practicable in most cases.
However, what can be done is to insert a physical barrier between the loop conductor and the
person who might otherwise come too close to it. This barrier can be of any non-magnetic,
non electrically conducting material.
10 Measurement uncertainty
The total measurement uncertainty includes sensor position and orientation, operating
conditions and, for in-situ measurements, magnetic background noise (although if the system
complies with IEC 60118-4, the effect of noise is negligible).

Annex A
(informative)
Rationale for this product-family magnetic field emission standard
for audio-frequency induction-loop systems (AFILS) in the context
of human exposure to non-ionizing radiation

Why is such a standard needed? Because the European Low Voltage Directive includes
"radiation" in its essential requirements, and although that was probably originally thought of
as "ionizing radiation" from cathode-ray tubes, it is now interpreted to include non-ionizing
radiation as well. There are also exposure limits in place in the USA and probably other
countries, or there will be in the foreseeable future. Consequently, the manufacturer of any
product that emits electric or magnetic fields or electromagnetic energy must be able to
demonstrate that its emissions are not hazardous. In practice, if there is any doubt, this is
very difficult to prove, and very costly, without a standard to apply. The CE mark may not
legally be applied to the product, and it may not be marketed in the EU, unless it satisfies all
the essential requirements of the low voltage directive.
In the case of AFILS, a person can be able to approach the loop conductor arbitrarily closely,
in fact this is inherent in the function of neck loops, looped cushions, pillow-pads and looped
chairs. But it can also occur with portable AFILS and floor-level area-coverage loops. The
magnetic field strength close to a loop conductor is always very high indeed. Table A.1 shows
the assessment of a typical AFILS in the context of IEC 62311 [4].
For complex reasons, the European exposure limits are included in a council
recommendation, and will be in future directives, rather than in harmonized standards. They
come from a published paper by the International Commission on Non-Ionizing Radiation
Protection (ICNIRP), the latest edition of which was published in 2010. The limits are of two
kinds: reference levels and basic restrictions. Reference levels are intended to simplify the
determination of compliance, but they may be exceeded if it can be shown that the basic
restrictions are met. For low-frequency magnetic fields, the reference levels for occupational
and general public are shown in the figure below.
Magnetic field strength
1 000
100 1 000 10 000
Frequency  Hz
Occupational 2010 General public 2010
IEC
Figure A.1 – ICNIRP magnetic field reference levels
Field strength  A/m
– 12 – IEC 62489-2:2014 © IEC 2014
Example
Where there are critical high field strength regions, the influence of the magnetic fields of
other conductors than the one nearest to the measuring point is normally negligible. The field
distribution can thus be assumed to be that of a single conductor, with a field strength falling
in inverse proportion to the radial distance from the centre of the conductor. This allows a vast
simplification of the assessment procedure.
The ICNIRP Guide indicates that a quasi-peak measurement, substantially in accordance with
the peak programme meter type II of IEC 60268-10, is appropriate and convenient.
For a neck loop, the current required to produce a magnetic field strength of 400 mA/m at the
hearing aid is very difficult to calculate and is best measured as described in IEC 60118-4.
This current need not normally be maintained at frequencies above 1,6 kHz, due to the shape
of the spectrum of speech signals. The reference level value of the magnetic field strength at
1,6 kHz for the general public is H = 40 A/m. For a maximum r.m.s. loop conductor current, I,
normally occurring for less than 5 s, of 0,5 A (this is the actual current multiplied by the
number of turns, which can be from 1 to approximately 30, depending on design), this value of
H is exceeded within a distance of
r=I/2πH
which is 2,0 mm in this case. Compliance with the reference level can therefore be achieved if
the diameter of the loop cable, over the insulation, exceeds the diameter of the loop
conductor bundle by at least 4,0 mm.
Table A.1 – Application to AFILS of Table 1 of IEC 62311:2007 "Characteristics
and parameters of the equipment to be considered"
Information Further detailed description Applied to AFILS
needed of the information needed
Frequency Frequency of emissions Nominally 100 Hz to 5 kHz
Waveform Waveform and other information such as duty Speech and music. Very complex: needs
factor for establishment of peak-and/or special attention.
average emission
Multiple frequency Does the equipment produce fields at more Yes
sources than one frequency or fields with a high
harmonic content?
Are the emissions simultaneous? Yes
Emission of Voltage differences and any coupling parts None
electric fields e.g. metallic surfaces charged at a voltage
potential
Emission of Current flow and any coupling parts e.g. The magnetic field is generated by a loop, in
magnetic fields coils, transducers or loops which the audio-frequency current flows.
Emission of Generation or transmission of high frequency Not significant (EMC considerations ensure
electromagnetic signals and any radiating parts e.g. that)
fields antennas, loops, transducers and external
cables
Contact currents Possibility of touching conducting surfaces No appreciable contact currents can be
when either the surface or the person is generated
exposed to electromagnetic fields?
Whole body Fields produced by equipment extend over In some cases
exposure region occupied by the whole body
Partial body Fields produced by equipment extend over In some cases
exposure only part of region occupied by the body, or
over region occupied by limbs
Information Further detailed description Applied to AFILS
needed of the information needed
Duration/time Duty cycle of emissions, on/off time of power Very variable; minutes to hours
variation used or emitted by equipment. Variation of
power use or emissions during production
process
Homogeneity Extent to which the strength of the fields Very great
varies over the body or region of the body
that is exposed. Shall be measured without
the presence of a body
Far/near field Are exposures in near field? Propagating Near field only
near field? Far field?
Pulsed/transient Are the emissions pulse-modulated or true No
fields pulses?
Are there occasional or periodic transients in Yes
the field?
Physical size Is the equipment so small that any significant In some cases
exposure will be to part of the body only?
In relation to the wavelength (operating Very small compared with the wavelength
frequency)
Is it so big that different parts will contribute In some cases
to exposures "independently"?
Power What is the emitted power? Very low indeed. The emission is a magnetic
induction field from a loop antenna much
smaller than the wavelength of the highest
frequency concerned, 5 kHz
What is the power consumption? Varies from a few Watts to several hundred
Watts. This power is dissipated in the
amplifier and the resistance of the loop
antenna conductor
If there is an antenna system, what is the Very low indeed: see above
effective radiated power?
Distance (source What is the spatial relationship between the Very variable, close contact to many metres
to user) equipment and the operator or user when it of separation
is used normally? The distance used for the
assessment shall be specified by the
manufacturer and be consistent with the
intended usage of the equipment
Intended usage How is the equipment commonly used? An audio-frequency magnetic field (speech or
music or both) is produced in a volume of
space in which users of hearing aids
equipped with telecoils can receive the audio
information
Operating conditions? See IEC 60118-4
Conditions of intended usage producing the Proximity of the user to the loop antenna.
highest emission or absorption? Hearing aids with telecoils typically fail to
reproduce signals from magnetic fields much
stronger than 1 A/m without unacceptable
distortion
How does the intended usage affect the Very variable, they can be very close or very
spatial relationship between the equipment distant
and the user?
Can the usage affect the emission Yes, if there are large metal objects in the
characteristics of the equipment? vicinity of a portable system
Can the equipment be part of a system? It IS a system
Interaction Do the emitted fields change if the equipment No
sources/user is close to the body?
Does the equipment couple to the body Yes
during use?
– 14 – IEC 62489-2:2014 © IEC 2014
Bibliography
[1] ICNIRP Guidelines for limiting exposure to time-varying electric, magnetic, and
electromagnetic fields (1 Hz - 100 kHz), International Commission on Non-Ionizing
Radiation Protection (ICNIRP), published in Health Physics 99(6);818-836; 2010
[2] GROVER, F.W., Inductance Calculations, New York, Dover Publications, re-published
[3] IEC 62233, Measurement methods for electromagnetic fields of household appliances
and similar apparatus with regard to human exposure
[4] IEC 62311:2007, Assessment of electronic and electrical equipment related to human
exposure restrictions for electromagnetic fields (0 Hz – 300 GHz)

____________
– 16 – IEC 62489-2:2014 © IEC 2014
SOMMAIRE
AVANT-PROPOS . 17
INTRODUCTION . 19
1 Domaine d’application . 20
2 Références normatives . 20
3 Valeurs assignées . 20
4 Situation concernant les normes actuelles . 20
5 Configurations des boucles . 21
5.1 Principaux types de configuration . 21
5.2 Considérations générales . 21
5.3 Boucles de grande surface . 21
5.4 Boucles de surface moyenne . 22
5.5 Boucles de petite surface . 22
5.6 Antennes solénoïdes. 22
6 Calculs . 23
6.1 Généralités . 23
6.2 Antennes solénoïdes. 23
7 Mesures . 23
7.1 Généralités . 23
7.2 Signal d’entrée . 24
7.3 Instrument de mesure . 24
8 Comparaison des résultats calculés ou mesurés avec les indications ou les
limites . 24
9 Respect des limites ou des indications . 24
10 Incertitude de mesure . 25
Annexe A (informative) Justifications pour cette norme de famille de produits relative
aux émissions de champ magnétique, concernant les systèmes de boucle d’induction
audiofréquences (AFILS) dans un contexte d’exposition humaine au rayonnement non
ionisant . 26
Bibliographie . 30

Figure 1 – Un transducteur d’induction auriculaire, avec un corps d'appareil de
correction auditive contour d’oreille pour fournir une échelle . 22
Figure A.1 – Niveaux de référence du champ magnétique ICNIRP . 27

Tableau 1 – Restrictions de base . 24
Tableau A.1 – Tableau 1 de l'IEC 62311:2007, "Caractéristiques et paramètres de
l’équipement à considérer", appliqués à l’AFILS . 28

COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
ÉLECTROACOUSTIQUE –
SYSTÈMES DE BOUCLES D’INDUCTION
AUDIOFRÉQUENCES POUR AMÉLIORER L'AUDITION –

Partie 2: Méthodes de calcul et de mesure des émissions de champ
magnétique basse fréquence à partir de la boucle pour l’évaluation
de la conformité aux instructions sur les limites d’exposition humaine

AVANT-PROPOS
1) La Commission Electrotechnique Internationale (IEC) est une organisa
...