Measurement procedures for electric and magnetic field levels generated by AC power systems with regard to human exposure

This International Standard establishes measurement procedures for electric and magnetic field levels generated by AC power systems to evaluate the exposure levels of the human body to these fields. This standard is not applicable to DC power transmission systems. This International Standard is applicable to public exposure in the domestic environment and in areas accessible to the public. This standard specifies fundamental procedures for the measurement of fields, and, with regard to human exposure, for obtaining a field value that corresponds to a spatial average over the entire human body. This standard is not applicable to occupational exposure associated with, for example, the operation and/or maintenance of the power systems. Such exposure may occur when working inside a distribution or transmission substation, a power plant, in a manhole or a tunnel for underground cables, or on an overhead line tower or pole.

Magnetische Felder, die von Wechselstrom-Energieversorgungssystemen erzeugt werden - Messverfahren im Hinblick auf die Exposition der Allgemeinbevölkerung

Procédures pour la mesure des champs électriques et magnétiques générés par les réseaux d'énergie électrique CA en rapport avec l'exposition humaine

La CEI 62110:2009 établit des procédures de mesure des niveaux de champs électriques et magnétiques générés par des systèmes d'alimentation à courant alternatif, afin d'évaluer les niveaux d'exposition du corps humain à ces champs. La présente norme ne s'applique pas aux systèmes de transport à courant continu. La CEI 62110:2009 s'applique à l'exposition humaine dans l'environnement domestique et dans les lieux qui sont accessibles augrand public. Elle spécifie les procédures fondamentales destinées à mesurer des champs, et concernant l'exposition humaine, à obtenir une valeur de champ correspondant à la moyenne spatiale sur l'ensemble du corps humain. La CEI 62110:2009 s'applique pas à l'exposition en milieu professionnel associée, par exemple, à l'exploitation et/ou la maintenance des systèmes d'alimentation. Une telle exposition peut avoir lieu lorsqu'on travaille dans un poste électrique de distribution ou de transport, une centrale, dans un puis d'accès ou un tunnel pour câbles souterrains, ou sur un poteau ou un pylône de ligne aérienne.

Merilni postopki za merjenje nivoja električnih in magnetnih polj, ki jih generirajo izmenični napajalni sistemi, z vidika izpostavljenosti ljudi (IEC 62110:2009)

Ta mednarodni standard vzpostavlja merilne postopke za merjenje električnih in magnetnih polj, ki jih generirajo izmenični napajalni sistemi, za vrednotenje ravni izpostavljenosti človeškega telesa tem poljem. Ta standard ne velja za enosmerne sisteme prenosa električne energije. Ta mednarodni standard velja za javno izpostavljenost v domačem okolju in na območjih, dostopnih javnosti. Ta standard določa bistvene postopke za merjenje polj in, z vidika izpostavljenosti ljudi, za pridobivanje vrednosti polja, ki ustreza prostorskemu povprečju za celotno človeško telo.  Ta standard ne velja za izpostavljenost pri delu, povezano na primer z delovanjem in/ali vzdrževanjem napajalnih sistemov. Do takšne izpostavljenosti lahko pride med delom v razdelilni postaji za distribucijo ali prenos električne energije, v elektrarni, vstopnem jašku ali tunelu za podzemne kable ali na nadzemnih električnih stolpih ali drogovih.

General Information

Status
Published
Publication Date
18-Apr-2010
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
25-Jan-2010
Due Date
01-Apr-2010
Completion Date
19-Apr-2010

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SLOVENSKI STANDARD
SIST EN 62110:2010
01-maj-2010
0HULOQLSRVWRSNL]DPHUMHQMHQLYRMDHOHNWULþQLKLQPDJQHWQLKSROMNLMLKJHQHULUDMR
L]PHQLþQLQDSDMDOQLVLVWHPL]YLGLNDL]SRVWDYOMHQRVWLOMXGL ,(&
Measurement procedures for electric and magnetic field levels generated by AC power
systems with regard to human exposure
Magnetische Felder, die von Wechselstrom-Energieversorgungssystemen erzeugt
werden - Messverfahren im Hinblick auf die Exposition der Allgemeinbevölkerung
Procédures pour la mesure des champs électriques et magnétiques générés par les
réseaux d'énergie électrique CA en rapport avec l'exposition humaine
Ta slovenski standard je istoveten z: EN 62110:2009
ICS:
17.220.20 0HUMHQMHHOHNWULþQLKLQ Measurement of electrical
PDJQHWQLKYHOLþLQ and magnetic quantities
29.240.01 2PUHåMD]DSUHQRVLQ Power transmission and
GLVWULEXFLMRHOHNWULþQHHQHUJLMH distribution networks in
QDVSORãQR general
SIST EN 62110:2010 en,fr
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 62110:2010

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SIST EN 62110:2010

EUROPEAN STANDARD
EN 62110

NORME EUROPÉENNE
December 2009
EUROPÄISCHE NORM

ICS 17.220.20; 29.240


English version


Electric and magnetic field levels generated by AC power systems -
Measurement procedures with regard to public exposure
(IEC 62110:2009)


Champs électriques et magnétiques Magnetische Felder,
générés par les systèmes d'alimentation die von Wechselstrom-
à courant alternatif - Energieversorgungssystemen erzeugt
Procédures de mesure des niveaux werden -
d'exposition du public Messverfahren im Hinblick
(CEI 62110:2009) auf die Exposition
der Allgemeinbevölkerung
(IEC 62110:2009)




This European Standard was approved by CENELEC on 2009-11-01. 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 obtained 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 Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, 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 Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Central Secretariat: Avenue Marnix 17, B - 1000 Brussels


© 2009 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 62110:2009 E

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SIST EN 62110:2010
EN 62110:2009 - 2 -
Foreword
The text of document 106/177/FDIS, future edition 1 of IEC 62110, prepared by IEC TC 106, Methods for
the assessment of electric, magnetic and electromagnetic fields associated with human exposure, was
submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 62110 on
2009-11-01.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
(dop) 2010-08-01
national standard or by endorsement
– latest date by which the national standards conflicting
(dow) 2012-11-01
with the EN have to be withdrawn
Terms defined in Clause 3 appear in italics throughout the document.
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 62110:2009 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 61000-2-2 NOTE  Harmonized as EN 61000-2-2:2002 (not modified).
__________

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SIST EN 62110:2010
- 3 - EN 62110:2009
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 applies. 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

1)
IEC 61786 - Measurement of low-frequency magnetic and - -
electric fields with regard to exposure of human
beings - Special requirements for instruments
and guidance for measurement




1)
Undated reference.

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SIST EN 62110:2010

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SIST EN 62110:2010

IEC 62110
®
Edition 1.0 2009-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside


Electric and magnetic field levels generated by AC power systems –
Measurement procedures with regard to public exposure

Champs électriques et magnétiques générés par les systèmes d’alimentation à
courant alternatif – Procédures de mesure des niveaux d’exposition du public

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
XA
CODE PRIX
ICS 17.220.20; 29.240 ISBN 2-8318-1059-3
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

---------------------- Page: 7 ----------------------

SIST EN 62110:2010
– 2 – 62110 © IEC:2009
CONTENTS
FOREWORD.5
INTRODUCTION.7
1 Scope.8
2 Normative reference .8
3 Terms and definitions .8
4 Measurement principle for electric and magnetic fields .9
4.1 General .9
4.2 Instruments .9
4.3 Harmonic content .10
4.4 Record of measurement result.10
4.5 Measurement considerations .11
4.5.1 Field orientation.11
4.5.2 Measurement locations.12
4.5.3 Perturbing effects of an operator in electric field measurement.12
4.5.4 Effects from other sources in magnetic field measurement .12
4.5.5 Humidity condition in electric field measurement .12
5 Fundamental measurement procedures for electric and magnetic fields.12
5.1 General procedure .12
5.2 Single-point measurement.13
5.3 Three-point measurement.13
5.4 Five-point measurement .14
6 Measurement procedures for finding the maximum exposure level to an electric
field .15
6.1 Overhead lines .15
6.2 Underground cables .15
6.3 Substations and power system equipment .15
7 Measurement procedures for finding the maximum exposure level to a magnetic
field .16
7.1 Overhead lines .16
7.2 Underground cables .16
7.3 Substations and power system equipment .16
Annex A (informative) Characteristics of electric fields generated by AC overhead
18
lines.
Annex B (informative) Characteristics of magnetic fields generated by AC power
systems .30
Annex C (informative) Concept of the three-point measurement with regard to the
average exposure level.42
Annex D (informative) Example of a reporting form for field measurement .47
Bibliography.50

Figure 1 – Heights of the three-point measurement.13
Figure 2 – Five-point measurement.14
Figure A.1 – Linear charge distribution above ground .19
Figure A.2 – General n-phase system with ground .20
Figure A.3 – Electric field levels under an overhead transmission line.22

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SIST EN 62110:2010
62110 © IEC:2009 – 3 –
Figure A.4 – Electric field levels under an overhead transmission line with bundled
conductors.22
Figure A.5 – Electric field levels and non-uniformity under a 77 kV overhead
transmission line – Effect of heights of conductors.24
Figure A.6 – Electric field levels and non-uniformity under a 500 kV overhead
transmission line – Effects of the heights of conductors .25
Figure A.7 – Electric field levels under a 77 kV overhead transmission line – Effect of
separation between conductors.26
Figure A.8 – Electric field levels and non-uniformity under a 500 kV overhead
transmission line – Effect of separation between conductors.27
Figure A.9 – Vertical and horizontal components of electric field levels under a 77 kV
overhead transmission line .27
Figure A.10 – Vertical and horizontal components of electric field levels under a
500 kV overhead transmission line.28
Figure A.11 – Electric field contour of a 25 kV overhead line.28
Figure A.12 – Electric field profile along the wall of a building and at 1 m above ground
level.29
Figure B.1 – Magnetic field levels under a 77 kV overhead transmission line .32
Figure B.2 – Magnetic field levels under a 500 kV overhead transmission line .33
Figure B.3 – Magnetic field levels and non-uniformity under a 77 kV overhead
transmission line – Effect of heights of conductors.34
Figure B.4 – Magnetic field levels and non-uniformity under a 500 kV overhead
transmission line – Effect of heights of conductors.35
Figure B.5 – Magnetic field levels and non-uniformity under a 77 kV overhead
transmission line – Effect of separation between conductors.36
Figure B.6 – Magnetic field levels under a 500 kV overhead transmission line – Effect
of separation between conductors.37
Figure B.7 – Values of semi-major and semi-minor components (r.m.s.) of magnetic
field levels under a 77 kV overhead transmission line .38
Figure B.8 – Values of semi-major and semi-minor components (r.m.s.) of magnetic
field levels under a 500 kV overhead transmission line .38
Figure B.9 – Magnetic field levels and non-uniformity under an overhead distribution
line (6 600 V / 100 V) .39
Figure B.10 – Magnetic field levels and non-uniformity above underground cables –
Effect of buried depth .40
Figure B.11 – Magnetic field levels and non-uniformity above underground cables –
Effect of separation between conductors.40
Figure B.12 – Measured magnetic field levels and non-uniformity around a 6 600 V
pad-mounted transformer.41
Figure B.13 – Measured magnetic field levels and non-uniformity around 6 600 V
vertical cables.41
Figure C.1 – A spheroidal human model .42
Figure C.2 – The model in the magnetic field generated by a straight cable .43
Figure C.3 – Magnetic field levels generated by a straight cable .43
Figure C.4 – The model in the magnetic field generated by three parallel cables .44
Figure C.5 – Magnetic field levels generated by three balanced parallel cables .44
Figure C.6 – The model in the magnetic field generated by underground cables .45
Figure C.7 – Magnetic field levels generated by underground cables .45
Figure C.8 – The model in the magnetic field generated by overhead wires .46

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SIST EN 62110:2010
– 4 – 62110 © IEC:2009
Figure C.9 – Magnetic field levels generated by balanced overhead wires .46

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SIST EN 62110:2010
62110 © IEC:2009 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

ELECTRIC AND MAGNETIC FIELD LEVELS GENERATED BY AC POWER
SYSTEMS – MEASUREMENT PROCEDURES
WITH REGARD TO PUBLIC 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
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and
non-governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates
closely with the International Organization for Standardization (ISO) in accordance with conditions determined
by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
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
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
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 62110 has been prepared by IEC technical committee 106:
Methods for the assessment of electric, magnetic and electromagnetic fields associated with
human exposure.
The text of this standard is based on the following documents:
FDIS Report on voting
106/177/FDIS 106/185/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.
Terms defined in Clause 3 appear in italics throughout the document.

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SIST EN 62110:2010
– 6 – 62110 © IEC:2009
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result 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 publication using a colour printer.

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SIST EN 62110:2010
62110 © IEC:2009 – 7 –
INTRODUCTION
All populations of the world are now exposed to electric and magnetic fields and the levels will
continue to increase with developing industry and technology. A number of countries have
implemented regulations on public exposure to these fields. Therefore, in order to evaluate
human exposure levels to these fields adequately, common measurement procedures are
required by not only professionals of national authorities and electric power industries, but
also the general public.
This standard is applied to the measurement of fields generated by AC power systems in
areas accessible to the public. It establishes a common measurement procedure to evaluate
the exposure levels of the human body to electric and magnetic fields among the general
public.
The values obtained are for use to determine whether the fields comply with exposure limits
by comparing them with the field limits for general public exposure such as the reference
levels from the ICNIRP (International Commission on Non-Ionizing Radiation Protection)
1)
Guidelines [1] , MPE (maximum permissible exposure) from the IEEE (Institute of Electrical
and Electronics Engineers) [2] or in national regulations. If the values obtained are higher
than the reference level or MPE, it does not necessarily mean that the basic restriction has
been exceeded, in which case other methods must be used to ensure that basic restriction is
not exceeded.
The values obtained by using the procedures in this standard are for the load conditions
occurring at the time of measurement. Therefore, in the case of magnetic field, in order to
check compliance with some exposure guidelines or regulations these values may need to be
extrapolated to take account of the maximum load of the circuits.
This standard is not applicable to occupational exposure associated with, for example, the
operation and/or maintenance of the power systems. Such exposure may occur when working
inside a distribution or transmission substation, a power plant, in a manhole or a tunnel for
underground cables, or on an overhead line tower or pole.
___________
1)
 Numbers in square brackets refers to the Bibliography.

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SIST EN 62110:2010
– 8 – 62110 © IEC:2009
ELECTRIC AND MAGNETIC FIELD LEVELS GENERATED BY AC POWER
SYSTEMS – MEASUREMENT PROCEDURES
WITH REGARD TO PUBLIC EXPOSURE




1 Scope
This International Standard establishes measurement procedures for electric and magnetic
field levels generated by AC power systems to evaluate the exposure levels of the human
body to these fields. This standard is not applicable to DC power transmission systems.
This International Standard is applicable to public exposure in the domestic environment and
in areas accessible to the public.
This standard specifies fundamental procedures for the measurement of fields, and, with
regard to human exposure, for obtaining a field value that corresponds to a spatial average
over the entire human body.
This standard is not applicable to occupational exposure associated with, for example, the
operation and/or maintenance of the power systems. Such exposure may occur when working
inside a distribution or transmission substation, a power plant, in a manhole or a tunnel for
underground cables, or on an overhead line tower or pole.
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 61786, Measurement of low-frequency magnetic and electric fields with regard to
exposure of human beings – Special requirements for instruments and guidance for
measurements
3 Terms and definitions
For the purposes of this document, the following terms and definitions given below apply.
Internationally accepted SI-units are used throughout the standard.
NOTE The distinction between “magnetic flux density” and “magnetic field strength” is only relevant when
considering magnetic fields in magnetic materials. In air it is common to use “magnetic fields” as a generic term to
cover both of these two quantities.
3.1
single-point measurement
procedure to measure the field level at a specified height, used for uniform fields
NOTE The conditions under which the field can be considered as uniform or non-uniform are given in section 5.1.
3.2
three-point measurement
procedure to measure the field levels at three specified heights at a single location, used for
non-uniform fields

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SIST EN 62110:2010
62110 © IEC:2009 – 9 –
3.3
five-point measurement
procedure to measure the field levels at five points at a specified height, used for non-uniform
fields generated by field sources below the floor or the ground
3.4
average exposure level
spatial average over the entire human body of fields to which the individual is exposed
3.5
three-point average exposure level
arithmetic mean of the three values obtained from the three-point measurement or of the
largest three values obtained from the five-point measurement
NOTE This arithmetic mean is used as an estimate of the average exposure level at a single location.
3.6
maximum exposure level
the maximum of the single-point measurements or average exposure levels over the area of
interest
3.7
power system
system consisting of overhead lines and underground cables, substations and other power
distribution and transmission equipment. Railway systems are covered by a specific standard
and therefore are excluded from the present standard.
4 Measurement principle for electric and magnetic fields
4.1 General
Detailed generic information and requirements regarding measurement of electric and
magnetic fields are given in IEC 61786 and in other technical documents such as CIGRE
technical brochures [6][8] and IEEE guides [7][9].
4.2 Instruments
Instruments for measuring electric and magnetic fields shall meet the requirements regarding
calibration and specification given in IEC 61786 or another appropriate national or
international standard. These instruments should be used under appropriate conditions,
particularly with regard to electromagnetic immunity, temperature, and humidity,
recommended by the manufacturer.
A three-axis instrument measures r.m.s. values of resultant field F . A single-axis instrument
r
can be used to obtain F by measuring F , F , and F using Equation (1).
r x y z,
2 2 2
F = F + F + F (1)
r x y z
where
F , F , and F are r.m.s. values of the orthogonal three-axis components of electric or
x y z
magnetic fields.
When the field has no harmonics, F can also be obtained by measuring F and F , and
r max min
then using Equation (2).

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SIST EN 62110:2010
– 10 – 62110 © IEC:2009
2 2
F = F + F (2)
r max min
where
F is the maximum r.m.s. value of the semi-major axis of the field ellipse;

max
F is the minimum r.m.s. value of the semi-minor axis of the field ellipse.
min
4.3 Harmonic content
Harmonics are generally caused by non-linear equipment. Harmonics may be present on
transmission lines and on distribution lines. Generally, the total harmonic voltage distortion of
AC power distribution systems (see [3][4]) is low enough to not significantly affect the
exposure, and so it is normally not necessary to quantify the harmonic content. AC
transmission systems have lower harmonic contents.
Where there is significant concern that the harmonic content of fields cannot be ignored,
existing methods of assessing the field harmonic content should be used following IEC 61786
for measurement. The assessment of the fields taking account of the harmonic frequencies
should be evaluated according to the procedure specified in the safety standard (e.g. [5]) to
be applied.
4.4 Record of measurement result
In the measurement report, the following information should be recorded:
– date, time, and weather conditions (e.g. sunny, rain, snow and wind conditions) when the
meas
...

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