IEC TR 62630:2010

Guidance for evaluating exposure from multiple electromagnetic sources

IEC/TR 62630:2010(E) describes exposure evaluation concepts and techniques for the overall exposure level in spatial regions and occupants caused by the simultaneous exposure to multiple narrowband electromagnetic (EM) sources. Throughout this Technical Report, it is assumed that the exposure evaluation occurs under static conditions, i.e., the source position and transmit-mode characteristics (e.g. emitted power, modulation scheme, etc.) of the device(s) under test do not vary significantly over the time required to carry out the evaluation using the chosen evaluation technique (e.g., field measurements). IEC/TR 62630:2010 provides guidance to IEC TC 106 project teams on how to evaluate the combined exposures from multiple electromagnetic (EM) sources in the frequency range 100 kHz to 300 GHz when specific absorption rate (SAR) and equivalent power density (S) are the relevant exposure metrics, as defined by the main international guidelines recommending limits on human exposure to EM fields.

General Information

• Status: Published
• Publication Date: 09-Mar-2010
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 17.220.20 - Measurement of electrical and magnetic quantities
• ICS: 33.050.10 - Telephone equipment
• Technical Committee: TC 106 - Methods for the assessment of electric, magnetic and electromagnetic fields associated with human exposure
• Drafting Committee: WG 4 - TC 106/WG 4
• Current Stage: PPUB - Publication issued
• Start Date: 30-Jun-2010
• Completion Date: 10-Mar-2010

Standards Content (Sample)

IEC/TR 62630 ®
Edition 1.0 2010-03
TECHNICAL
REPORT
colour
inside
Guidance for evaluating exposure from multiple electromagnetic sources

IEC/TR 62630:2010(E)
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IEC/TR 62630 ®
Edition 1.0 2010-03
TECHNICAL
REPORT
colour
inside
Guidance for evaluating exposure from multiple electromagnetic sources

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
X
ICS 17.220.20; 33.050.10 ISBN 978-2-88910-776-6
– 2 – TR 62630 © IEC:2010(E)
CONTENTS
FOREWORD.4
INTRODUCTION.6
1 Scope.7
2 Normative references .7
3 Terms, definitions and abbreviations .8
3.1 Terms and definitions .8
3.2 Physical quantities .16
3.3 Constants.16
3.4 Abbreviations .16
3.5 Vector notations .17
4 Overview .17
5 Classification of devices and EM sources .20
5.1 General aspects .20
5.2 Device classification based on the intended use: user-centric versus node-
centric .20
5.3 EM source classification: single-channel versus band-wide transmitters .21
6 Combined exposure from multiple narrowband EM sources .23
6.1 Guidance on the selection of the exposure summation approach.23
6.2 Correlation between signals emitted by different EM sources .24
6.3 Relevant exposure metrics .24
6.4 Combined exposure from uncorrelated EM sources .25
6.5 Combined exposure evaluation of correlated EM sources.25
6.5.1 Accurate estimate of the true field vector sum .25
6.5.2 Conservative combined exposure evaluation using scalar sensors .26
Annex A (informative) Frequency allocations for some common wireless services .29
Annex B (informative) Supporting analytical details.32
Annex C (informative) Examples of combined exposure evaluations .39
Bibliography.46

Figure 1 – Electrical paths from the radiating elements of each panel in a dual-panel
antenna system to a field-point P on the ρ-z symmetry plane .18
Figure 2 – True vector sum of the complex field envelopes produced at the field-point
P by the individual antenna panels in Figure 1 at two different measurement times.19
Figure 3 – Simultaneous exposure at the location X by multiple sector-antennas
belonging to adjacent tri-sector cellular masts (labelled #1 and #2).21
Figure 4 – Different approaches yielding distinct upper-bounds of the field vector-sum .28
Figure B.1 – Vectorial interpretation of inequality (B25), yielding an upper-bound of the
true field vector-sum (red arrow) .37
Figure C.1 – CAD model of the antenna system for a mobile phone, including a
GSM/UMTS antenna and a Bluetooth antenna .39
Figure C.2 – Qualitative description of the individual and combined SAR distributions
for a mobile phone transmitting simultaneously GSM and Wi-Fi signals .40
Figure C.3 – Communications tower shared by different network operators.41
Figure C.4 – Smart antenna formed by 8 vertical 5-element ground-backed dipole
arrays. .42

TR 62630 © IEC:2010(E) – 3 –
Figure C.5 – Power density distributions on the surface Σ (ρ = 1 m) derived via
ρ
Equations (6), (10), and (12) for the 3,5 GHz smart antenna shown in Figure C.4 .44
Figure C.6 – Overestimations produced by Equations (10) and (12) over the exposure
evaluation area Σ (ρ = 1 m) for the 3,5 GHz smart antenna shown in Figure C.4.45
ρ
Table 1 – Source classes: characteristics and examples of source classification .22
Table 2 – Guidance on the selection of suitable evaluation techniques .23
Table A.1 – Frequency allocations and bandwidths for common wireless technologies .29

– 4 – TR 62630 © IEC:2010(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
GUIDANCE FOR EVALUATING EXPOSURE
FROM MULTIPLE ELECTROMAGNETIC SOURCES

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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The main task of IEC technical committees is to prepare International Standards. However, a
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data of a different kind from that which is normally published as an International Standard, for
example "state of the art".
IEC/TR 62630, which is a technical report, 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 technical report is based on the following documents:
Enquiry draft Report on voting
106/173/DTR 106/196/RVC
Full information on the voting for the approval of this technical report can be found in the
report on voting indicated in the above table.

TR 62630 © IEC:2010(E) – 5 –
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
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.
A bilingual version of this publication may be issued at a later date.

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.
– 6 – TR 62630 © IEC:2010(E)
INTRODUCTION
This Technical Report provides guidance to IEC TC 106 project teams on how to evaluate the
combined exposures from multiple electromagnetic (EM) sources in the frequency range
100 kHz to 300 GHz when specific absorption rate (SAR) and equivalent power density (S)
are the relevant exposure metrics, as defined by the main international guidelines
recommending limits on human exposure to EM fields.
SAR and power density are energy-intensive exposure metrics related to tissue heating. Other
metrics have been defined in some exposure guidelines to regulate different effects, e.g.,
electro-stimulation. Guidance on evaluating exposure from multiple EM sources based on
these other exposure metrics requires separate further study
This Technical Report considers the combination of exposures from multiple EM sources
a) which reside on the same electronic device (e.g. multi-band mobile phone);
b) arising from multiple devices (e.g. mult
...