IEC TS 62597:2011

IEC/TS 62597 ®
Edition 1.0 2011-10
TECHNICAL
SPECIFICATION
SPÉCIFICATION
TECHNIQUE
Measurement procedures of magnetic field levels generated by electronic and
electrical apparatus in the railway environment with respect to human exposure

Procédures de mesure des niveaux de champ magnétique générés par les
appareils électriques et électroniques dans l'environnement ferroviaire en
regard de l'exposition humaine

IEC/TS 62597:2011
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IEC/TS 62597 ®
Edition 1.0 2011-10
TECHNICAL
SPECIFICATION
SPÉCIFICATION
TECHNIQUE
Measurement procedures of magnetic field levels generated by electronic and
electrical apparatus in the railway environment with respect to human exposure

Procédures de mesure des niveaux de champ magnétique générés par les
appareils électriques et électroniques dans l'environnement ferroviaire en
regard de l'exposition humaine

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX T
ICS 45.060 ISBN 978-2-88912-735-1

– 2 – TS 62597  IEC:2011
CONTENTS
FOREWORD . 4

INTRODUCTION . 6

1 Scope . 7

2 Normative references . 7

3 Terms and definitions . 7

4 Measurement procedure . 9

4.1 General . 9

4.2 Rolling stock . 10
4.2.1 General . 10
4.2.2 Accessible areas for workers inside rolling stock . 10
4.2.3 Public areas inside rolling stock . 10
4.2.4 Areas outside rolling stock (public and workers) . 11
4.3 Fixed installation . 12
4.3.1 General . 12
4.3.2 Open railway route (public and workers) . 12
4.3.3 Areas close to fixed power supply installations (public and workers) . 13
4.3.4 Platform (public and workers) . 13
4.3.5 Simulation/calculation . 13
4.4 Test conditions . 14
4.4.1 Test of rolling stock . 14
4.4.2 Test of fixed installation . 14
4.5 Test environment. 15
5 Measurement technique . 15
5.1 General . 15
5.2 Frequency range . 15
5.3 Measurement equipment . 15
5.3.1 General . 15
5.3.2 Field probes . 15
5.3.3 Summation of spatial components . 15
5.3.4 Data logging . 16
5.3.5 Dynamic range . 16
5.3.6 Isotropy . 16

5.3.7 Linearity . 16
5.3.8 Calibration and accuracy . 16
5.4 Evaluation methods . 16
5.4.1 General . 16
5.4.2 DC magnetic field . 16
5.4.3 AC magnetic field . 16
5.5 Measurement execution . 17
5.5.1 General . 17
5.5.2 Rolling stock . 17
5.5.3 Fixed installation . 18
6 Report . 18
Annex A (informative) Test plan . 20
Bibliography . 24

TS 62597  IEC:2011 – 3 –
Figure 1 – External surface of the rolling stock . 11

Figure 2 – Measuring point of surface method . 12

Table 1 – Location and distances . 13

– 4 – TS 62597  IEC:2011
INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
MEASUREMENT PROCEDURES OF MAGNETIC FIELD LEVELS

GENERATED BY ELECTRONIC AND ELECTRICAL APPARATUS

IN THE RAILWAY ENVIRONMENT WITH RESPECT TO 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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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.
The main task of IEC technical committees is to prepare International Standards. In

exceptional circumstances, a technical committee may propose the publication of a technical
specification when
• the required support cannot be obtained for the publication of an International Standard,
despite repeated efforts, or
• the subject is still under technical development or where, for any other reason, there is the
future but no immediate possibility of an agreement on an International Standard.
Technical specifications are subject to review within three years of publication to decide
whether they can be transformed into International Standards.
IEC 62597, which is a technical specification, has been prepared by IEC technical committee
9: Electrical equipment and systems for railways.
This technical specification is based on EN 50500.

TS 62597  IEC:2011 – 5 –
The text of this technical specification is based on the following documents:

Enquiry draft Report on voting

9/1429/DTS 9/1499A/RVC
Full information on the voting for the approval of this technical specification 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.

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
• transformed into an International standard,
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
– 6 – TS 62597  IEC:2011
INTRODUCTION
The intention of this Technical Specification is to summarize existing measuring/calculation

methods for determining the magnetic fields in the space around the equipment mentioned in

the scope.
TS 62597  IEC:2011 – 7 –
MEASUREMENT PROCEDURES OF MAGNETIC FIELD LEVELS

GENERATED BY ELECTRONIC AND ELECTRICAL APPARATUS

IN THE RAILWAY ENVIRONMENT WITH RESPECT TO HUMAN EXPOSURE

1 Scope
This Technical Specification applies to apparatus, systems and fixed installations which are

intended for use in the railway environment. The frequency range covered is 0 Hz to 300 GHz.
Technical considerations and measurements are necessary for frequencies from d.c. to
20 kHz because no relevant field strengths are expected above due to the physical nature of
EMF-sources in the railway environment.
a) The regulations regarding the protection of human beings (also bearing active
implantable medical devices) during exposure to non-ionizing electromagnetic fields in
the railway environment are different according to the countries worldwide.
The object of this Technical Specification is to summarize measurement and
simulation/calculation procedures of magnetic field levels generated by electronic and
electrical apparatus in the railway environment with respect to human exposure (also for
human beings bearing active implantable medical devices).
Transient conditions, such as short circuit, earth fault and transformer inrush are excluded.
Not covered are personal electronic devices (e.g. mobile phones, notebook computers,
wireless communication systems, etc.) of passengers and workers.
Not covered are intentional transmitters with frequencies higher than 20 kHz.
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
IEC 62236 (all parts), Railway applications – Electromagnetic compatibility
IEC 62311, Assessment of electronic and electrical equipment related to human exposure
restrictions for electromagnetic fields (0 Hz – 300 GHz)
ISO/IEC 17025, General requirements for the competence of testing and calibration
laboratories
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 62236, IEC 62311,
IEC 61786 and the following apply.

– 8 – TS 62597  IEC:2011
3.1
workers
drivers, train-staff and all people working in the railway environment. National definition of

“workers” will have a priority if any

3.2
platform
place where passengers can enter, leave and change trains

3.3
fixed installation
infrastructure of railway environment without rolling stock
3.4
electric traction system / feeding system
railway electric distribution network to provide energy for an electrical motive power unit.
EXAMPLE This system may comprise
– contact line systems,
– return circuit systems,
– running rails of non-electric traction systems, which are in the vicinity of, and conductively
connected to the running rails of an electric traction system,
– electrical installations, which are supplied from contact lines either directly or via a
transformer,
– electrical installations in power plants and substations, which are utilized solely for
generation and distribution of power directly to the contact line,
– electrical installations of switching stations
3.5
main line
railway line for passenger and freight trains in regional and long-distances operation
3.6
urban transport
railway line for underground trainsets, trams, LRV (Light Rail Vehicles), trolleybuses to
operate within the boundary of a metropolitan area
3.7
rolling stock
smallest unit which can be operated covering all vehicles with or without motors
3.8
level crossing
crossing of railway line and public way (street or footpath) on the same level
3.9
working area
area for workers without access for general public. National definitions of this area have
priority.
3.10
the railway environment
the surrounding objects or region which may be influenced by electronic and electrical
apparatus of the railway (see IEC 62236-2)

TS 62597  IEC:2011 – 9 –
3.11
public
all people in the railway environment except workers

3.12
open railway route
railway route except station
4 Measurement procedure
4.1 General
In railways three electromagnetic sources can affect human beings: rolling stock, traction
power supply and signalling equipment.
According to generic EMF standard IEC 62311, there are two separate summation regimes for
simultaneous exposure to fields of different frequencies. They depend on the effects of the
exposure. In the frequency range from 1 Hz to 10 MHz the electrical stimulation is relevant. In
the frequency range from 100 kHz to 300 GHz, thermal effects are relevant.
As the detectable emission of rolling stock, traction power supply and signalling equipment is
in the frequency range from d.c. to 100 kHz, measurements, simulation and calculation are
restricted to this range. Accordingly, only one summation regime is applied. In this frequency
range the magnetic field is dominant and the electric field can be neglected.
As power of signalling equipment is low in comparison with other sources of EMF in the
railway environment, its contribution can be neglected.
The load within the railway system can change widely in short times. Emission is related to
load.
The measurement procedure of the whole railway system is divided into two cases.
Case 1: Rolling stock (see 4.2)
– measurements inside rolling stock, and
– measurements outside rolling stock.
Case 2: Fixed installation of existing infrastructure (see 4.3)
– measurement of existing railway infrastructure,
– simulation/calculation of worst case situation (e.g. bridges, level crossing, maximum

possible current in overhead lines, third rails).
NOTE Compliance of rolling stock can be demonstrated with the first explained case. Compliance of fixed
installation can be demonstrated with the second explained case.
For the apparatus, systems and fixed installations in railway environment there are basic
restrictions for general public and workers specified in ICNIRP and IEEE standards (see
Bibliography).
With compliance of case 1 and case 2, it can be assumed that the whole railway system
complies with the relevant requirements and limits.
Subclause 4.2 defines the measurement points in established areas inside and outside rolling
stock.
Subclause 4.3 defines the measurement points in established areas in fixed installation and
gives details regarding simulation/calculation.

– 10 – TS 62597  IEC:2011
Subclause 4.4 defines the test conditions during the measurement of the magnetic field.

Subclause 4.5 is related to the test environment.

A test plan for rolling stock and fixed installation is given in Annex A.

4.2 Rolling stock
4.2.1 General
The following measurement points are specified inside and outside rolling stock:

4.2.2 Accessible areas for workers inside rolling stock
The measurements indicate the emissions of the train equipment in standstill and dynamic
condition (see 4.4.1).
Measurements shall be carried out where workers are located when seated or accessing
areas in the train during normal operation conditions of train taking into account the sources
of emission within the train. This is defined as the occupied volume.
The occupied volume can be measured either by the surface method or by the volume method.
Surface method:
The enclosing surface of the volume shall be measured at a minimum distance (under the
sensor restriction) and at an agreed number of measuring points (e.g. by measurement on the
floor surface above emission sources and if necessary additional measurement heights above
the floor may be 0,5 m, 1,0 m and 1,5 m).
Failure to satisfy the value of the limits using the surface method does not necessarily mean
the occupied volume limits are exceeded.
Volume method:
The occupied volume shall be measured at typical places where workers can be located. The
measurement heights above the floor shall be 1,0 m and 1,5 m. The horizontal measuring
distance to the walls is 0,3 m or at the minimum distance (> 0,3 m) where workers can be.
4.2.3 Public areas inside rolling stock

The measurements indicate the emissions of the train equipment in standstill and dynamic
condition (see 4.4.1).
Measurements shall be carried out in areas occupied by public during normal operation
conditions of train taking into account the sources of emission within the train. This is defined
as the occupied volume.
The occupied volume can be measured either by the surface method or by the volume method
defined in 4.2.2.
However in the case of the volume method the measurement heights above the floor shall be
0,3 m, 1,0 m and 1,5 m.
TS 62597  IEC:2011 – 11 –
4.2.4 Areas outside rolling stock (public and workers)

The measurements indicate the emissions of the train equipment in standstill condition (see

4.4.1).
Measurements shall be carried out where public or workers are located outside the train

during normal operation conditions of train when stationary taking into account the sources of

emission within the train. This is defined as the occupied volume.

The occupied volume can be measured either by the surface method or by the volume method.

The external surface of the rolling stock is defined as shown in Figure 1. The occupied volume
does not consider places below or above the rolling stock.

Surface of the rolling stock
Height above
rail level  (m)
Rail level
Train equipment that
emits magnetic fields
IEC  2336/11
Figure 1 – External surface of the rolling stock
– Surface method:
The external surface of the train shall be measured at a minimum distance (under the sensor
restriction) and at an agreed number of measuring points (e.g. by measurement at the height
of the centre of the nearest side of the equipment as defined in Figure 2).

– 12 – TS 62597  IEC:2011
Surface of the rolling stock
Height above
rail level  (m)
Measuring point
Rail level
Train equipment that Centre of train
emits magnetic fields equipment
IEC  2337/11
Figure 2 – Measuring point of surface method
Failure to satisfy the value of the limits using the surface method does not necessarily mean
the occupied volume limits are exceeded.
– Volume method:
Measurements shall be carried out at distances of 0,3 m to the train surface taking into
account the sources of emission of the rolling stock (e.g. power converters, power cables and
power inductors) at 0,5 m, 1,5 m and 2,5 m height from the top of the running rails (rail level).
Measurements for public shall not be carried out at the same side of the third rail with respect
to the tracks.
4.3 Fixed installation
4.3.1 General
Demonstration of compliance of the existing fixed installation shall include fixed electric
traction system of railway environment.
Positions where compliance has to be demonstrated are given in 4.3.1 to 4.3.3.

Simulation/calculation can give worst case figures (see 4.3.4).
A test plan is given in Annex A.
For measurement of fixed installation, measurement should take into account coherency and
compatibility with the measurement procedures for electric power systems.The international
EMF standard for electric power systems IEC 62110 should be referenced.
4.3.2 Open railway route (public and workers)
Measurements and/or simulation/calculation regarding public shall be carried out at the
distances measured from the centre of the nearest track of the considered system as given in
Table 1, or at higher distances within the nearest accessible area for public, at 1,0 m or 1,5 m
above ground level (standing area) where people can be at the detected location, see Table 1.

TS 62597  IEC:2011 – 13 –
Measurements for workers on open railway routes shall be carried out at the closest possible

(not restricted) position to the sources of emission where workers can be located.

NOTE 1 A measurement height of 1,0 m is a common practice for electric power systems in Japan

and a measurement height of 1,5 m is common in Europe.

Table 1 – Location and distances

Location Horizontal distance from centre Remark

of track
m
Main line 10 (for public) If not regulated by legislative

requirements
Urban transport 3 (for public) If not regulated by legislative
requirements
Trams, trolley buses, etc. 0
Level crossings 0
Bridges 0
Underpass 0
Combined systems (main line and urban line close together) have to be regarded individually
which may lead to other distances.
NOTE 2 There may be cases where the location of maximum field strength is different from the centre of the track.
In these cases the place with the maximum field strength has to be considered.
4.3.3 Areas close to fixed power supply installations (public and workers)
Measurements and/or simulation/calculation shall be carried out at the closest possible (not
restricted) position to the sources of emission from fixed power supply installations where
public and workers can be located (e.g. as marked on the floor or given by fences).
There are two sets of measurement heights:
0,5 m, 1,0 m and 1,5 m and
0,3 m, 0,9 m and 1,5 m.
Only one set has to be chosen.
NOTE Measurement heights of 0,5 m, 1,0 m and 1,5 m are a common practice for electric power systems in
Japan and the horizontal distance is in these cases 0,2 m or at the minimum distance (> 0,2 m) where public and
workers can be. If the field to be measured is considered to be uniform, measurements at heights of 0,5 m and

1,5 m can be omitted (same as single-point measurement at a height of 1,0 m).
Measurement heights of 0,3 m, 0,9 m and 1,5 m are common practice in Europe for public areas – without the
height of 0,3 m for worker areas as it is not expected to have children as workers. The horizontal measuring
distance to the walls or fences is 0,3 m or at the minimum distance (> 0,3 m) where public and workers can be.
4.3.4 Platform (public and workers)
On platforms three measurement heights above the platform level are given: 0,5 m, 1,0 m and
1,5 m.
The horizontal distance shall be 0,3 m or the closest possible horizontal distance (>0,3 m)
from the edge of the platform where public and workers can be.
4.3.5 Simulation/calculation
If measurements cannot cover the worst case conditions, simulation/calculation with maximum
expected current values (to be set by the infrastructure manager) shall be carried out.

– 14 – TS 62597  IEC:2011
Harmonics known to be lower than a threshold value of 10 % of the limit value at the

corresponding frequency can be neglected.

Validation of the calculation/simulation shall be performed by comparison between

calculated/simulated results and measured values for known conditions.

NOTE Expected maximum current values may be extrapolated from notch curve for rolling stock and from the

maximum allowable load of electric power equipment for substations.

4.4 Test conditions
4.4.1 Test of rolling stock
Tests are to be done under normal operating conditions, only.
The condition of the rolling stock during the magnetic field measurements is described below:
– Standstill condition (S)
The rolling stock is not moving.
The traction circuits shall be under voltage but not operating. The auxiliary circuits shall
operate and all the relevant appliances shall be active (e.g. air conditioning/heating, lights,
window heater, electric generators).
– Dynamic condition (D)
The rolling stock starts from the standstill with maximum acceleration to maximum speed,
coasting and maximum electrical brake to stop.
The traction circuits shall be under voltage and operating. The auxiliary circuits shall
operate and the load shall be active.
The maximum value of the field strength shall be recorded together with the line current.
There may be rolling stock (e.g. urban transport) which cannot accelerate with maximum line
current under test conditions, or supply systems that cannot be deliberately set such that the
rolling stock will draw the maximum line current for the purposes of the test. In these cases
the maximum emission shall be calculated based on the measurement results and monitored
line current using an appropriate method (e.g. linear extrapolation).
NOTE 1 Attention also should be paid to the emissions of car borne equipment, and the emissions of the third rail
or catenary. While individual fields from car borne equipment will vary as a function of the current in the device,
catenary or third rail field will vary as a function of number of cars and current.
The test has, as far as possible, to be done without the influence of other rolling stock.
If different circuits are used in the electrical brake systems they have to be tested separately.

NOTE 2 The line receptivity may be between zero and maximum and is not controlled for the purposes of this test.
4.4.2 Test of fixed installation
– Open railway route and platform
The actual line current of the open railway route/platform as the significant source of
emission shall be noted during emission tests.
Maximum emission shall be calculated based on the measurement results and monitored
line current using an appropriate method (e.g. extrapolation).
– Fixed power supply installation
The actual loading of the fixed power supply installation shall be noted during emission
tests.
Maximum emission shall be calculated based on the measurement results and monitored
line current using an appropriate method (e.g. extrapolation).

TS 62597  IEC:2011 – 15 –
4.5 Test environment
Any magnetic induction sources outside the rolling stock and along the trackside can

influence the measurements carried out. In order to be able to correlate particular magnetic

induction values it is necessary, beforehand and during the measurements, to indicate the

positions of any possible external sources on a plan of the line run.

5 Measurement technique
5.1 General
This clause defines the frequency range and the measurement equipment, evaluation
methods and measurement execution.
5.2 Frequency range
Measurements and/or calculation and simulation shall be performed from d.c. up to 20 kHz.
NOTE 1 There may be measurement instrumentation with a gap between 1 Hz and 5 Hz which can be used also.
This can be justified by the fact that the limit decreases from 1 Hz to 5 Hz by a factor 1/f². In matching the limit at
5 Hz it is assumed that the limit is matched at lower frequencies too.
NOTE 2 Measurements are necessary for frequencies up to 20 kHz because no relevant field strengths are
expected above.
NOTE 3 The frequency range of measurement can be reduced if no relevant field strengths are expected above.
See A.1.3.
5.3 Measurement equipment
5.3.1 General
The measurement equipment shall meet the requirements as defined in the relevant
regulations and shall be in accordance with the following technical requirements as a
minimum.
The centre of each field probe shall be the reference point for the given measuring distances
in this Technical Specification.
5.3.2 Field probes
The field probes should be compatible to IEC 61786 and shall meet the following
requirements:
• measurement of the d.c. magnetic field: tri-axial isotropic probe;
• measurement of the a.c. magnetic field:
– tri-axial probe with three orthogonal loops, loop with maximum 100 cm area with a
minimum frequency range of 5 Hz to 20 kHz, or
– tri-axial probe fluxgate sensor with a minimum frequency range of d.c. to 20 kHz.
NOTE For measurements in the railway environment the magnetic flux density B is the magnitude of a field vector
that is equal to the magnetic field H multiplied by the permeability µ .
B=µ ⋅H
5.3.3 Summation of spatial components
Three measurements shall be performed at the same time in three orthogonal planes to obtain
the different components of the field. The resultant H-field would be given by the following
formula:
– 16 – TS 62597  IEC:2011
2 2 2
H= H +H +H
x y z
For a.c. fields the summation has to be performed either in the time domain after filtering or in

the frequency domain after FFT (Fast Fourier Transform) of the measured components of the

field.
NOTE The formula for H will give worst case values for summation in the frequency domain as the phase relation

between the components is lost. More accurate methods may be used.

5.3.4 Data logging
It is recommended to use data logging equipment to make the measurement data available for
further offline evaluation.
5.3.5 Dynamic range
The dynamic range of the measurement chain shall cover the range at the appropriate applicable
limit.
5.3.6 Isotropy
The isotropy deviation of the complete system shall be 5 % or less.
5.3.7 Linearity
The linearity deviation of the complete system regarding measured field strength values shall
be not more than ± 5 % in the required dynamic range.
5.3.8 Calibration and accuracy
All relevant measurement equipment shall be calibrated for the used frequency range. The
uncertainty of the complete measurement chain from the field probes to the final display unit
shall be not more than designated range (typical values may be 20 %).
The complete measurement chain shall be checked to verify its performance and accuracy.
5.4 Evaluation methods
5.4.1 General
The methods used for the evaluation and assessment of measurement data should be in line
with the relevant regulations.

5.4.2 DC magnetic field
The evaluation of DC magnetic fields shall be done by using the formula stated in 5.3.3.
5.4.3 AC magnetic field
5.4.3.1 General
For a.c. magnetic fields, two basic methods for data evaluation and assessment are
applicable. The method defined by ICNIRP guidelines (see Bibliography) is FFT (see below).
This is the basic method. Further methods can be found in IEEE standards (see bibliography).
As the FFT overestimates magnetic fields in comparison with the results of time domain
method (the railway environment is characterized by pulsed and complex non-sinusoidal
waveforms) the application of the second method (as mentioned in ICNIRP statement (see
Bibliography)) may be more realistic in some cases.

TS 62597  IEC:2011 – 17 –
In case of exceeding the limit because of transients they should be identified. Transients with

a duration of less then 1 s, e.g. during switching events, can be disregarded.

5.4.3.2 Frequency domain
Evaluation in the frequency domain with FFT-analyser, digital signal processor or equivalent

equipment (online or offline of recorded data) and followed by spectral weighting and

summation of spectral components as required by particular relevant requirements/standards

and as necessary for conversion of the measured signals to values in terms of magnetic flux
density (B(f)).
Record length of FFT-data (i.e. observation time and bandwidth of spectral signal) and
sampling frequency should be in accordance with the relevant requirements/standards.
Recommendations/typical parameters (not mandatory):
Time window: Hanning (no overlap)
Record length: 0,5 s (realtime FFT)
Sampling frequency: > 40 kHz
Summation of spectral components: linear, spectral lines under a threshold value of 10 % of
the limit value are not taken into account.
NOTE Evaluation of transients and variables frequencies by FFT analysis may cause wrong results. If peak hold
result complies with limit values, a detailed analysis of each time step is not necessary. Changes in load (e.g.
change from accelerating to coasting) may cause errors in FFT analysis. Therefore a separate investigation of
different operating conditions without the transition is allowed.
5.4.3.3 Time domain
Evaluation in the time domain (dB(t)/dt or B(t)) with digital or analogue filters with appropriate
filter characteristics in order to perform the spectral weighting and conversion of the
measured signals to values in terms of magnetic flux density (B(t)), if necessary followed by
evaluation as required by particular basic requirements/standards (example is given in
ICNIRP statement (see Bibliography)).
Sampling frequency: > 40 kHz
NOTE The two methods
– will produce identical results for sinusoidal magnetic fields (assuming that the weighting functions are the

same for both methods);
– will produce comparable results for periodic magnetic fields;
– may produce different results for impulse shaped magnetic fields (for multi frequency signals the FFT method
overestimates the exposure).
5.5 Measurement execution
5.5.1 General
Measure all three axis of the magnetic field at the same time.
For each point of every measurement area, magnetic fields are measured in the following way:
5.5.2 Rolling stock
– Inside rolling stock:
Measuring all 3 axis of the magnetic field in static condition for a duration of (30 – 60) s.

– 18 – TS 62597  IEC:2011
Measuring all 3 axis of the magnetic field in dynamic condition from the standstill with

maximum acceleration to maximum speed, coasting for a duration of at least 10 s and

maximum electrical break to stop.

For each measuring point and each condition one measurement is sufficient.

– Outside rolling stock:
Measuring all 3 axis of the magnetic field in static condition for a duration of (30 – 60) s.

5.5.3 Fixed installation
Monitor the current affecting the magnetic field at the same time of magnetic field

measurement.
During measurement different railway related and other magnetic field sources may contribute
to measuring result.
Measurement arrangements should be such that a correlation between line current and field
strength is possible to find the maximum value of field strength.
6 Report
Guidelines to the report can be found in ISO/IEC 17025.
The following information pertaining to the instrumentation and measurements should also be
provided in all cases:
– date of measurements;
– post processing method;
– time of measurements;
– test set-up (e.g. heights and location of the measurement);
– environmental conditions (e.g. weather conditions, other field sources, magnetizing
materials);
– measurement uncertainty;
– evaluation results (e.g. ICNIRP value of each performed assessment);
– spectrum analysis for selected places (e.g. with high emission or requested from third
party);
– any dev
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