oSIST prEN 50413:2018

Basic standard on measurement and calculation procedures for human exposure to electric, magnetic and electromagnetic fields (0 Hz - 300 GHz)

European standard establishes the procedures and methodology on measurement and calculation of quantities associated with the assessment of human exposure to electric, magnetic and electromagnetic fields in the frequency range from 0 Hz to 300 GHz. It deals with quantities that can be measured or calculated in free space, notably electric and magnetic field strength and includes the measurement and calculation of quantities inside the body that forms the basis for protection guidelines.
In particular the standard provides information on
− definitions and terminology,
− characteristics of electric, magnetic and electromagnetic fields,
− measurement of exposure quantities,
− instrumentation requirements,
− methods of calibration,
− measurement techniques and procedures for evaluating exposure,
− calculation methods for exposure assessment.
The object of this standard is to establish a common reference for the assessment of electrical equipment in relation to human exposure from non-ionising electromagnetic fields.

Grundnorm zu Mess- und Berechnungsverfahren der Exposition von Personen in elektrischen, magnetischen und elektromagnetischen Feldern (0 Hz bis 300 GHz)

Norme de base pour les procédures de mesures et de calculs pour l'exposition des personnes aux champs électriques, magnétiques et électromagnétiques (0 Hz - 300 GHz)

Osnovni standard za merjenje in izračunavanje izpostavljenosti ljudi električnim, magnetnim in elektromagnetnim poljem (0 Hz–300 GHz)

Standards Content (sample)

SLOVENSKI STANDARD
oSIST prEN 50413:2018
01-marec-2018

2VQRYQLVWDQGDUG]DPHUMHQMHLQL]UDþXQDYDQMHL]SRVWDYOMHQRVWLOMXGLHOHNWULþQLP

PDJQHWQLPLQHOHNWURPDJQHWQLPSROMHP+]±*+]
Basic standard on measurement and calculation procedures for human exposure to
electric, magnetic and electromagnetic fields (0 Hz - 300 GHz)
Grundnorm zu Mess- und Berechnungsverfahren der Exposition von Personen in
elektrischen, magnetischen und elektromagnetischen Feldern (0 Hz bis 300 GHz)
Norme de base pour les procédures de mesures et de calculs pour l'exposition des
personnes aux champs électriques, magnétiques et électromagnétiques (0 Hz - 300
GHz)
Ta slovenski standard je istoveten z: prEN 50413
ICS:
17.200.20 Instrumenti za merjenje Temperature-measuring
temperature instruments
33.100.01 Elektromagnetna združljivost Electromagnetic compatibility
na splošno in general
oSIST prEN 50413:2018 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 50413:2018
EUROPEAN STANDARD DRAFT
prEN 50413
NORME EUROPÉENNE
EUROPÄISCHE NORM
January 2018
ICS 17.200.20; 33.100.01 Will supersede EN 50413:2008
English Version
Basic standard on measurement and calculation procedures for
human exposure to electric, magnetic and electromagnetic fields
(0 Hz - 300 GHz)

Norme de base pour les procédures de mesures et de Grundnorm zu Mess- und Berechnungsverfahren der

calculs pour l'exposition des personnes aux champs Exposition von Personen in elektrischen, magnetischen und

électriques, magnétiques et électromagnétiques (0 Hz - 300 elektromagnetischen Feldern (0 Hz bis 300 GHz)

GHz)
This draft European Standard is submitted to CENELEC members for enquiry.
Deadline for CENELEC: 2018-04-06.
It has been drawn up by CLC/TC 106X.

If this draft becomes a European Standard, 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.

This draft European Standard was established by CENELEC 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 CEN-CENELEC Management Centre has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,

Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,

Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden,

Switzerland, Turkey and the United Kingdom.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are aware and to

provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and

shall not be referred to as a European Standard.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2018 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.

Project: 63533 Ref. No. prEN 50413 E
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Contents Page

European foreword ............................................................................................................................................ 3

1 Scope ..................................................................................................................................................... 4

2 Normative references ........................................................................................................................... 4

3 Terms and definitions .......................................................................................................................... 5

4 Introduction ........................................................................................................................................... 9

4.1 General remarks.................................................................................................................................... 9

4.2 Exposure assessment approaches .................................................................................................. 10

4.3 Static and low frequency fields ......................................................................................................... 10

4.4 High frequency range ......................................................................................................................... 10

4.5 Multiple frequency fields and multiple sources .............................................................................. 10

5 Assessment of human exposure by measurement ......................................................................... 10

5.1 General remarks.................................................................................................................................. 10

5.2 Characterization of the field source.................................................................................................. 11

5.3 Electromagnetic field measurement ................................................................................................. 11

5.4 Body current measurement ............................................................................................................... 15

5.5 Contact current measurement ........................................................................................................... 15

5.6 SAR measurement .............................................................................................................................. 15

5.7 Uncertainty of measurement ............................................................................................................. 15

5.8 Calibration ........................................................................................................................................... 16

6 Assessment of exposure by calculation .......................................................................................... 16

6.1 Low frequency ..................................................................................................................................... 16

6.2 High frequency .................................................................................................................................... 17

6.3 Uncertainty of calculation .................................................................................................................. 17

7 Assessment report ............................................................................................................................. 17

7.1 General ................................................................................................................................................. 17

7.2 Items to be recorded in the assessment report ............................................................................... 17

Annex A (informative) List of standards ...................................................................................................... 19

Annex B (informative) Uncertainty assessment for the measurement of EMF ........................................ 21

B.1 Steps in establishing an uncertainty budget ................................................................................... 21

B.2 Examples for uncertainty budgets .................................................................................................... 24

Bibliography ..................................................................................................................................................... 26

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European foreword

This document (prEN 50413:2018) has been prepared by CLC/TC 106X “Electromagnetic fields in the human

environment”.
This document is currently submitted to the Enquiry.
The following dates are proposed:
• latest date by which the existence of this (doa) dor + 6 months
document has to be announced at national
level
• latest date by which this document has to be (dop) dor + 12 months
implemented at national level by publication of
an identical national standard or by
endorsement
• latest date by which the national standards (dow) dor + 36 months
conflicting with this document have to be (to be confirmed or
withdrawn modified when voting)
This document will supersede EN 50413:2008.

This document has been prepared under a mandate given to CENELEC by the European Commission and the

European Free Trade Association.
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1 Scope

This document provides general methods for measurement and calculation of quantities associated with human

exposure to electric, magnetic and electromagnetic fields in the frequency range from 0 Hz to 300 GHz. It is intended

specifically to be used for the assessment of emissions from products and comparison of these with the exposure

levels for the general public given in Council Recommendation 1999/519/EC, and those given for workers in Directive

2013/35/EU, as appropriate. It also is intended to be used for assessment of human exposure to electromagnetic fields

in the workplace to determine compliance with the requirements of Directive 2013/35/EU.

This standard deals with quantities that can be measured or calculated external to the body, notably electric and

magnetic field strength or power density, and includes the measurement and calculation of quantities inside the body

that forms the basis for protection guidelines. In particular the standard provides information on

• definitions and terminology,
• characteristics of electric, magnetic and electromagnetic fields,
• measurement of exposure quantities,
• instrumentation requirements,
• methods of calibration,
• measurement techniques and procedures for evaluating exposure,
• calculation methods for exposure assessment.

This standard may be used when no applicable electric, magnetic and electromagnetic field standard specific to a

product or technology exists. Annex A gives a list of relevant standards at the time of writing.

2 Normative references

The following documents are referred to in the text in such a way that some or all of their content constitutes

requirements 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.

EN 62311:2008, Assessment of electronic and electrical equipment related to human exposure restrictions for

electromagnetic fields (0 Hz - 300 GHz)

EN 61786-1:2014, Measurement of DC magnetic, AC magnetic and AC electric fields from 1 Hz to 100 kHz with regard

to exposure of human beings – Part 1: Requirements for measuring instruments

ISO/IEC Guide 98-3, Uncertainty of measurement – Part 3: Guide to the expression of uncertainty in measurement

(GUM:1995)

COUNCIL OF THE EUROPEAN UNION. Council Recommendation of 12 July 1999 on the limitation of exposure of

the general public to electromagnetic fields (0 Hz to 300 GHz) (1999/519/EC). Official Journal of the European

Communities. 1999, 199 (L) pp. 59–70

EUROPEAN PARLIAMENT AND COUNCIL OF THE EUROPEAN UNION. Directive 2013/35/EU of the European

Parliament and of the Council on the minimum health and safety requirements regarding the exposure of workers to

the risks arising from physical agents (electromagnetic fields) (20th individual Directive within the meaning of Article

16(1) of Directive 89/391/EEC) and repealing Directive 2004/40/EC. Official Journal of the European Union. 2013,

179 (L) p. 21
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3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
action level

operational levels established for the purpose of simplifying the process of demonstrating the compliance with relevant

ELVs or, where appropriate, to take relevant protection or prevention measures specified in this Directive

[SOURCE: Directive 2013/35/EU]
3.2
antenna

device that serves as a transducer between a guided wave for example in a coaxial cable and a free space wave, or

vice versa
3.3
basic restriction

restrictions on exposure to time-varying electric, magnetic, and electromagnetic fields that are based directly on

established health effects
[SOURCE: ICNIRP guidelines]
3.4
contact current

current flowing into the body resulting from contact with a conductive object in an electromagnetic field. This is the

localised current flow into the body (usually the hand, for a light brushing contact)

3.5
current density (J)

current per unit cross-sectional area flowing inside the human body as a result of direct exposure to electromagnetic

fields

Note 1 to entry: The current density is expressed in the unit ampere per square m (A/m ).

3.6
electric flux density (D)

vector quantity obtained at a given point by adding the electric polarization P to the product of the electric field strength

E and the permittivity of free space ε0:
D = ε0 E + P

Note 1 to entry: Electric flux density is expressed in units of coulombs per square m (C/m ).

Note 2 to entry: In vacuum, the electric flux density is at all points equal to the product of the electric field strength and the permittivity

of free space: D = ε E.
3.7
electric field strength (E)

vector quantity obtained at a given point that represents the force (F) on an infinitely small charge (q) divided by the

charge:
E =

Note 1 to entry: Electric field strength is expressed in the unit volt per m (V/m).

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3.8
exposure

exposure occurs when there is an electric, magnetic or electromagnetic field at the same location as the person from

an external source
3.9
exposure level
value of the quantity used to assess exposure
3.10
exposure limit values

values established on the basis of biophysical and biological considerations, in particular on the basis of scientifically

well-established short-term and acute direct effects, i.e. thermal effects and electrical stimulation of tissues.

Compliance with these limits will ensure that workers exposed to electromagnetic fields are protected against all known

adverse health effects
[source: Directive 2013/35/EU]
3.11
far-field region

region of the field of an antenna where the radial field distribution is essentially dependent inversely on the distance

from the antenna. In this region the field has a predominantly plane-wave character, i.e. locally uniform distribution of

electric field and magnetic field in planes transverse to the direction of propagation

Note 1 to entry: In the far-field region the vectors of the electric field E and the magnetic field H are perpendicular to each other and

the quotient between the value of the electric field strength E and the magnetic field strength H is constant and equals the impedance

of free space Z .
3.12
impedance of free space

impedance of free space Z0 is defined as the square root of the free space permeability µ divided by the permittivity

of free space ε
Z=≈≈120π Ω 377 Ω
3.13
isotropic

qualifies a physical medium or technical device where the relevant properties are independent of the direction

3.14
induced current (I)

current induced inside the body as a result of direct exposure to electromagnetic fields, expressed in the unit ampere

(A)
3.15
linearity of measurement instrument

maximum deviation over the measurement range of the measured quantity from the closest linear reference curve

defined over a given interval
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3.16
magnetic flux density (B)

the field vec/tor in a point that results in a force (F) on a charge (q) moving with the velocity (v)

F = q (v × B)

Note 1 to entry: The magnitude of the magnetic flux density is expressed in the unit Tesla (T)

3.17
magnetic field strength (H)

vector quantity obtained at a given point by subtracting the magnetization M from the magnetic flux density B divided

by the permeability of free space μ0:
HM−

Note 1 to entry: Magnetic field strength is expressed in the unit ampere per metre (A/m).

Note 2 to entry: In vacuum, the magnetic field strength is at all points equal to the magnetic flux density divided by the permeability

of free space: H = B / µ0.
3.18
modulation

process of modifying the amplitude, phase and/or frequency of a periodic waveform in order to convey information

3.19
near-field region

region generally in proximity to an antenna or other radiating structure, in which the electric and magnetic fields do not

have a substantially plane-wave character, but vary considerably from point to point. The near-field region is further

subdivided into the reactive near-field region, which is closest to the radiating structure and that contains most or

nearly all of the stored energy, and the radiating near-field region where the radiation field predominates over the

reactive field, but lacks substantial plane-wave character and is complex in structure

3.20
permeability (µ)

property of a material which defines the relationship between magnetic flux density B and magnetic field strength H. It

) and the relative permeability for specific
is commonly used as the combination of the permeability of free space (µ0
materials (µr)
µ µµ
where
µ is the relative permeability of the material
µ0 is the permeability of vacuum
Note 1 to entry: The permeability is expressed in units of henry per metre (H/m)
= =
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3.21
permittivity (ε)

property of a dielectric material, e.g., biological tissue, defined by the electric flux density D divided by the electric field

strength E
ε = ε ε = D / E
r 0
where
ε is the relative permittivity of the material
ε0 is the permittivity of vacuum

Note 1 to entry: The permittivity is expressed in units of farads per metre (F/m).

3.22
phantom

simplified model of the human body or body part composed of materials with dielectric properties close to the organic

tissue
3.23
power density (S)
power per unit area normal to the direction of electromagnetic wave propagation

Note 1 to entry: The power density is expressed in units of Watts per square m (W/m ).

Note 2 to entry: For plane waves the power density (S), electric field strength (E) and magnetic field strength (H) are related by the

impedance of free space Z0.
S= =Z×=H E× H

Note 3 to entry: Although many survey instruments indicate power density units, the actual quantities measured are E or H, or the

square of those quantities.
3.24
probe

input device of a measuring instrument, generally made as a separate unit, which transforms the measured input value

to a suitable output value
3.25
reference level

these levels are provided for practical exposure assessment purposes to determine whether the basic restrictions are

likely to be exceeded. Some reference levels are derived from relevant basic restrictions using measurement and/or

computational techniques, and some address perception and adverse indirect effects of exposure to EMF (from

ICNIRP guidelines)

Note 1 to entry: In any particular exposure situation, measured or calculated values can be compared with the appropriate reference

level. Compliance with the reference level will ensure compliance with the relevant basic restriction. If the measured or calculated

value exceeds the reference level, it does not necessarily follow that the basic restriction will be exceeded. However, whenever a

reference level is exceeded it is necessary to test compliance with the relevant basic restriction and to determine whether additional

protective measures are necessary.
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3.26
root-mean-square (r.m.s.)

r.m.s. value is obtained by taking the square root of the average of the square of the value of the time-varying function

taken throughout a suitable period of time

Note 1 to entry: For periodic functions a suitable time interval is any multiple of the period of the function. For non-periodic functions

the time interval used shall be recorded.
3.27
specific absorption rate (SAR)

time derivative of the incremental electromagnetic energy (dW) absorbed by (dissipated in) an incremental mass (dm)

contained in a volume element (dV) of given mass density ( ρ)
d dW d dW
SAR
  
dt dm dt ρ dV
 
Note 1 to entry: SAR is expressed in units of watts per kilogram (W/kg)
Note 2 to entry: SAR can be calculated by:
σ E
SAR = c |
SAR =
i at t
where
E r.m.s. value of the electric field strength in the tissue in V/m;
σ conductivity of body tissue in S/m;
ρ density of body tissue in kg/m ;
ci heat capacity of body tissue in J/kg K;
dT / dt time derivative of temperature in body tissue in K/s.
3.28
unperturbed field

field that exists in a space in the absence of a person or an object that could influence the field

Note 1 to entry: The field measured or calculated with a person or object present may differ considerably.

4 Introduction
4.1 General remarks

Electric, magnetic and electromagnetic fields can have direct and indirect effects on the human body. Depending on

the frequency of the fields, these can be effects on the nervous system in the low frequency range and thermal effects

in the high frequency range. Besides these direct effects there exist several indirect effects such as the occurrence of

contact currents or the possible influence on the intended operation of active medical implants. This standard

addresses only effects for which there exists a measurable limit.

The Council Recommendation 1999/519/EC provides basic restrictions and derived reference levels for exposure of

the general public in the areas where they spend significant time.

The Directive 2013/35/EU provides exposure limit values and derived action level for exposures in the workplace.

The basic restrictions given in the Recommendation, and the exposure limit values given in the Directive are in both

cases the actual limits which are expressed in terms of quantities that are mostly not measurable: including induced

currents or internal electric field strength for low frequency, specific absorption rate (SAR) for higher frequency and

power density for the highest frequencies.
= =
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The reference levels given in the Recommendation, and the action levels given in the Directive, are in both cases

derived from the actual limits and are expressed in terms of quantities that are measurable: including electric field

strength, magnetic field strength and contact current.

Exposure assessments may be based either on the reference levels (action levels), or on the basic restriction

(exposure limit value) taking account of specific characteristics of the particular field source or device being assessed.

4.2 Exposure assessment approaches

In general, either calculation or measurement procedures can be used for the assessment of exposure. In specific

circumstances there may be advantages of using one or the other of these. Whichever is used, it shall be applied in

such a way that it ensures compliance with limits under all reasonably foreseeable exposure scenarios.

4.3 Static and low frequency fields

The static and low frequency (up to 100 kHz) electric and magnetic fields are effectively independent from each other

and shall – if necessary – both be assessed. For a given exposure scenario the electric field strength depends on the

voltage used; the magnetic field strength or magnetic flux density depends on the electric current.

4.4 High frequency range

There exist several field types which should be assessed differently depending on the distance r from and the

dimension D of the radiating source. Table 1 indicates whether to measure E or H or both at different distances from

the field source.

For unintentional radiators, if it is not known whether the conditions for far field or radiating near field apply, then it is

necessary to measure both E and H.
Table 1 – Evaluation parameters
Reactive near field Radiating near field Far field
a 2 2
Distance r r < λ λ < r < 2D / λ λ < 2D / λ < r
E,H approximately 1/r No No Yes
Z = E/H ≠ Z0 approximately Z0 = Z0
To measure E and H E or H E or H

Strongly depending on type of radiating structure (D: biggest dimension of the radiating structure; i.e. diameter of

a parabolic antenna).
4.5 Multiple frequency fields and multiple sources

All relevant frequency component and field sources shall be taken into account when assessing exposure. In general,

low frequency and high frequency fields shall not be added together because their effects are different but at

intermediate frequencies (100 kHz to 10 MHz) where both types of effect are possible, it is necessary to consider both

effects. Proper summation procedures are given for the low frequency range (stimulation effects) in IEC 61786-2:2014,

4.2. Proper summation procedures are given for the high frequency and intermediate frequency ranges in EN 62311.

5 Assessment of human exposure by measurement
5.1 General remarks

Measurements of human exposure to electric, magnetic and electromagnetic fields can be classified as follows:

• measurement of electric, magnetic or electromagnetic field quantities (i.e. B, E, H, S);

• measurement of the limb induced current;
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• measurement of the contact current;
• measurement of the Specific Absorption Rate (SAR);
• measurement of the temperature.

EM field measurements have to differentiate between low- and high-frequency field measurements.

The range for low frequency measurements is from 0 Hz up to 10 MHz and the range for high frequency measurements

is from 100 kHz up to 300 GHz.

NOTE The underlying physiological effects of electromagnetic fields on the human body have no sharp frequency limit value

to distinguish between stimulation and thermal effects; this also shows up in the selection of the measurement equipment

necessary.
5.2 Characterization of the field source

To make meaningful measurements, the behaviour and characteristics (for example frequency, time-variability of

emission, input power) of the source of exposure (field or current) shall be determined and the operation of the

measurement equipment understood. Irrespective of the type of signal, time domain measurement may be used. This

can be especially helpful for non-sinusoidal, very fast, and pulsed signals. Also, the exposure quantities measured

should include all those needed to assess the extent of human exposure arising from the operation of the source.

What shall be measured is the maximum level to which someone is exposed under the operating conditions of the

source that are used when a person is permitted access.

The expected emission characteristics of the source should be understood, and it should be confirmed that these

match the results of measurements. Sometimes the source will be well documented, in which case the predicted

emissions may be comparatively simple to establish. Sometimes the source will be undocumented and its

characteristics shall be determined mostly by measurement. There will also be influences on the behaviour of the

source, such as ground conductivity, presence of reflecting objects etc. and these shall be considered.

More information is given in EN 62311:2008, Table 2.
5.3 Electromagnetic field measurement
5.3.1 Measurement instrumentation
5.3.1.1 Low frequency range

Electric and magnetic field meters shall be compliant with the requirements of EN 61786-1.

Magnetic flux density measurements shall be made with three-axis instruments and shall be of the resultant magnetic

field,

NOTE 1 Using single-axis instruments is possible in some cases, e.g. to know the direction of the field and the maximum magnetic

field, or in order to investigate the orientation and shape of the magnetic field ellipse, and in cases when the direction of a linearly

polarized field is already known.

NOTE 2 Some three-axis instrumentation can also determine the field parameters mentioned above.

The size of the probe or sensing elements shall be appropriate to the spatial variation of the field that is measured.

The sensing elements should be of area 0,01 m or smaller (5.8.2 of EN 61786-1:2014).

The pass-band of the instrument shall be appropriate to the frequency content of the field being measured. Where the

field is such that the pass-b
...