Railway applications - Rolling stock - Protective provisions relating to electrical hazards

This European Standard offers a set of rules that are applied in the design and manufacture of electrical installations and equipment to be used on rolling stock so as to protect the persons from electric shocks.
The methods used to satisfy the rules may differ, in accordance with the procedures and practices of the operating organization.
This European Standard is applicable to vehicles of rail transport systems, road vehicles powered by an external supply (e.g. trolley buses), magnetic levitated vehicles and to the electrical equipment installed in these vehicles.
This European Standard does not apply to
   mine railways in underground mines,
   crane installations, moving platforms and similar transport systems on rails,
   funicular railways,
   temporary constructions.
Testing of vehicles against the requirements of this European Standard is not included. For this, refer to EN 50215.

Bahnanwendungen - Fahrzeuge - Schutzmaßnahmen in Bezug auf elektrische Gefahren

Applications ferroviaires - Matériel roulant - Mesures de protection vis-à-vis des dangers d'origine électrique

Železniške naprave – Vozna sredstva – Zaščitni ukrepi proti nevarnostim električne napetosti

General Information

Status
Withdrawn
Publication Date
30-Apr-2003
Withdrawal Date
15-Jul-2020
Current Stage
9900 - Withdrawal (Adopted Project)
Start Date
16-Jul-2020
Due Date
08-Aug-2020
Completion Date
16-Jul-2020

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SLOVENSKI STANDARD
SIST EN 50153:2003
01-maj-2003
1DGRPHãþD
SIST EN 50153:1998
äHOH]QLãNHQDSUDYH±9R]QDVUHGVWYD±=DãþLWQLXNUHSLSURWLQHYDUQRVWLP
HOHNWULþQHQDSHWRVWL
Railway applications - Rolling stock - Protective provisions relating to electrical hazards
Bahnanwendungen - Fahrzeuge - Schutzmaßnahmen in Bezug auf elektrische Gefahren
Applications ferroviaires - Matériel roulant - Mesures de protection vis-à-vis des dangers
d'origine électrique
Ta slovenski standard je istoveten z: EN 50153:2002
ICS:
13.260 9DUVWYRSUHGHOHNWULþQLP Protection against electric
XGDURP'HORSRGQDSHWRVWMR shock. Live working
45.060.01 Železniška vozila na splošno Railway rolling stock in
general
SIST EN 50153:2003 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 50153:2003

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SIST EN 50153:2003
EUROPEAN STANDARD EN 50153
NORME EUROPÉENNE
EUROPÄISCHE NORM June 2002
ICS 45.060.00 Supersedes EN 50153:1996
English version
Railway applications -
Rolling stock -
Protective provisions relating to electrical hazards
Applications ferroviaires - Bahnanwendungen -
Matériel roulant - Fahrzeuge -
Mesures de protection vis-à-vis Schutzmaßnahmen in Bezug auf
des dangers d'origine électrique elektrische Gefahren
This European Standard was approved by CENELEC on 2002-05-01. 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, Czech Republic,
Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Luxembourg, Malta,
Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerland and United Kingdom.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
Central Secretariat: rue de Stassart 35, B - 1050 Brussels
© 2002 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 50153:2002 E

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SIST EN 50153:2003
EN 50153:2002 - 2 -
Foreword
This European Standard was prepared by SC 9XB, Electromechanical material on board of
rolling stock, of Technical Committee CENELEC TC 9X, Electrical and electronic
applications for railways.
This European Standard represents the second edition of the standard and is technically
based on the International Standard IEC 61991 which is the adaptation of EN 50153:1996
into IEC format. IEC 61991 was submitted successfully to a parallel vote in 1999. The
European references, special national conditions and A-deviations have been restored in this
European Standard.
The text of the draft was submitted to the Unique Acceptance Procedure and was approved
by CENELEC as EN 50153 on 2002-05-01.
This European Standard supersedes EN 50153:1996.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2003-05-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2005-05-01
Annexes designated “normative” are part of the body of the standard.
Annexes designated “informative” are given for information only.
In this standard, annexes A and B are normative and annex C is informative.
__________

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Table of contents
Page
Introduction . 4
1 Scope . 4
2 Normative references. 4
3 Definitions. 5
3.1 Definitions concerning persons. 5
3.2 Other definitions . 6
4 Classification of voltage bands . 8
4.1 General principles . 8
4.2 Connections between circuits . 8
4.3 Exceptions. 9
5 Protective provisions against direct contact. 9
5.1 Protection by insulation . 9
5.2 Protection by prevention of access . 9
5.3 Protection by the use of band I . 12
5.4 Warning labels. 13
6 Protective provisions against indirect contact. 13
6.1 General principles . 13
6.2 Protective bonding . 13
6.3 Disconnection of the supply. 14
6.4 Vehicle protective bonding. 14
6.5 Clarifications and exceptions . 15
7 Power circuits . 16
7.1 General principles . 16
7.2 Power circuit insulated from the vehicle body or bogie. 17
7.3 Power circuit using the vehicle body or bogie . 17
8 Additional requirements . 17
8.1 Current collectors. 17
8.2 Capacitors . 18
8.3 Plug and socket devices. 18
8.4 Special sources . 19
Annex A (normative) Special national conditions. 20
Annex B (normative) List of items where contracting parties
shall choose either a procedure or a mechanical device. 21
Annex C (informative) A-deviations. 22

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EN 50153:2002 - 4 -
Introduction
It is generally accepted that safety depends on human factors, based on the normal
behaviour of the operators involved, as well as upon technical factors.
For these reasons, this European Standard, in several instances, leaves a choice to the
contracting parties between two alternatives. These alternatives consist either in the
provision of operating rules, regulations and procedures, or in the application of technical
measures such as mechanical or electrical interlocking devices.
A list of the cases for which the contracting parties (e.g. user and manufacturer) should
reach agreement before signing the contract is included in annex B.
1 Scope
This European Standard offers a set of rules that are applied in the design and manufacture
of electrical installations and equipment to be used on rolling stock so as to protect the
persons from electric shocks.
The methods used to satisfy the rules may differ, in accordance with the procedures and
practices of the operating organization.
This European Standard is applicable to vehicles of rail transport systems, road vehicles
powered by an external supply (e.g. trolley buses), magnetic levitated vehicles and to the
electrical equipment installed in these vehicles.
This European Standard does not apply to
− mine railways in underground mines,
− crane installations, moving platforms and similar transport systems on rails,
− funicular railways,
− temporary constructions.
Testing of vehicles against the requirements of this European Standard is not included. For
this, refer to EN 50215.
2 Normative references
This European Standard incorporates, by dated or undated references, provisions from other
publications. These normative references are cited at the appropriate place in the text and
the publications are listed hereafter. For dated references, subsequent amendments to or
revisions of any of these publications apply to this European Standard only when
incorporated in it by amendment or revision. For undated references the latest edition of the
publication referred to applies (including amendments).
EN 50122-1 1997 Railway applications - Fixed installations
Part 1: Protective provisions relating to electrical safety and
earthing
EN 50124-1 2001 Railway applications - Insulation coordination
Part 1: Basic requirements - Clearances and creepage
distances for all electrical and electronic equipment
EN 50126 1999 Railway applications - The specification and demonstration of
Reliability, Availability, Maintainability and Safety (RAMS)

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EN 50163 1995 Railway applications - Supply voltages of traction systems
EN 50215 1999 Railway applications - Testing of rolling stock after completion
of construction and before entry into service
EN 60439 Series Low-voltage switchgear and controlgear assemblies
(IEC 60439 series, modified)
EN 60529 1991 Degrees of protection provided by enclosures (IP code)
+ corr. May 1993 (IEC 60529:1989)
EN 61310-1 1995 Safety of machinery - Indication, marking and actuation
Part 1: Requirements for visual, auditory and tactile signals
(IEC 61310-1:1995)
HD 366 S1 1977 Classification of electrical and electronic equipment with regard
to protection against electric shock
(IEC 60536: 1976)
HD 384 Series Electrical installations of buildings
(IEC 60364 series, modified)
HD 384.4.41 S2 1996 Electrical installations of buildings
Part 4: Protection for safety
Chapter 41: Protection against electric shock
(IEC 60364-4-41:1992, modified)
IEC 60050-191 1990 International Electrotechnical Vocabulary (IEV)
Chapter 191: Dependability and quality of service
IEC 60050-441 1984 Chapter 441: Switchgear, controlgear and fuses
IEC 60050-811 1991 Chapter 811: Electric traction
IEC 60050-826 1982 Electrical installations of buildings (harmonized as HD 384.2)
IEC 60479-1 1994 Effects of current on human beings and livestock
Part 1: General aspects
3 Definitions
For the purpose of this European Standard, the following definitions apply. For more
information relating to definitions of parts of the fixed installations, refer to
EN 50122-1 from which these definitions are derived.
NOTE  In order to avoid risks of misunderstanding, definitions used in the text are written in italics.
3.1 Definitions concerning persons
3.1.1
skilled person
a person who can judge the work assigned to him and recognize possible dangers on the
basis of his professional training, knowledge and experience and of his knowledge of the
relevant requirements [IEV 826-09-01]

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3.1.2
instructed person
a person adequately advised or supervised by skilled persons to enable him or her to avoid
dangers and to prevent risks which electricity may create [IEV 826-09-02]
3.1.3
ordinary person
a person who is neither a skilled person nor an instructed person [IEV 826-09-03]
3.2 Other definitions
3.2.1
closed electrical operating area
any room or location which serves exclusively for the operation of electrical equipment and is
kept secure by a means appropriate to the voltage and location
NOTE 1  Access to such areas is permitted only to skilled persons and instructed persons.
NOTE 2  The definition of closed electrical operating area can be suitable for underfloor or upperroof cabinets.
Generally speaking, it is any location (inside or outside the car body) which is kept secured because of the
voltage that can assume the equipment inside it. Access to such areas is not allowed to ordinary persons.
3.2.2
contact line
conductor system for supplying electrical energy to vehicles through current-collecting
equipment [IEV 811-33-01]
3.2.3
contact wire
electric conductor of an overhead contact line with which the current collectors make contact
[IEV 811-33-15]
3.2.4
direct contact
contact of persons or livestock with live parts [IEV 826-03-05]
3.2.5
earth
conductive mass of the earth, whose electrical potential at any point is conventionally taken
as equal to zero [IEV 826-04-01]
3.2.6
electrical operating area
any room or location which serves primarily for the operation of electrical equipment and is
normally entered only by skilled persons or instructed persons
NOTE  Generally speaking, an electrical operating area is any location (mainly inside the car body) where
electrical equipments operate. The above is the main function of this area but not the only one. In fact, normally
the area is not kept secured and the protection against direct contact is achieved by other means (e.g.
obstacles).
3.2.7
electric shock
dangerous physiological effect resulting from the passing of an electric current through a
human or animal body [IEV 826-03-04, mod.]

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3.2.8
exposed conductive part
any metallic or other form of conductive material which is not energized except in case of
failure, and which may be accessible to touch
3.2.9
failure
termination of the ability of an item to perform a required function
3.2.10
hazard
a physical situation with a potential of human injury [EN 50126, 3.17]
3.2.11
indirect contact
contact of persons or livestock with exposed conductive parts which have become live under
fault conditions [IEV 826-03-06]
3.2.12
interlocking device
a device which makes the operation of a switching device dependent upon the position or
operation of one or more other pieces of equipment [IEV 441-16-49]
3.2.13
live part
conductor or conductive part intended to be energized in normal use, including a neutral
conductor [IEV 826-03-01, mod.]
3.2.14
nominal voltage
voltage by which an installation or part of an installation is designated [IEV 826-02-01]
NOTE 1  The voltages are expressed by the value between poles, ripple-free for D.C. and by the r.m.s. value
between phases for A.C.
NOTE 2  The actual voltage may differ from the nominal voltage by a quantity within permitted tolerances. For
further information about traction systems supply voltages, see EN 50163.
3.2.15
obstacle
a part preventing unintentional direct contact, but not preventing direct contact by deliberate
action [IEV 826-03-14]
3.2.16
power circuit
a circuit carrying the current of the machines and equipment, such as convertors and traction
motors, which transmit the traction output [IEV 811-25-03]
3.2.17
protective bonding
equipotential connection for protective purposes

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3.2.18
protective conductor
conductor used for some protective measures for protection against electric shock for
electrically connecting any of the following parts:
− exposed conductive parts;
− main earthing terminal;
− earth electrode;
− earthed point of the source or artificial neutral [IEV 826-04-05, mod.]
4 Classification of voltage bands
4.1 General principles
This European Standard is based on the maximum supply voltages at which the equipment
or electrical circuits are subjected.
The voltages are classified into bands according to the nominal value as shown in Table 1.
Different installation rules apply to each of these bands.
The power supply of the various circuits installed in railway rolling stock are of different types
such as
− batteries,
− transformers,
− voltage dividers,
− rotating machines,
− static converters,
− capacitors,
− special sources.
Table 1 - Voltage bands
Band Nominal voltage
U
n
A.C. D.C.
V V
I
      U ≤ 25    U ≤ 60
II
25 < U ≤ 50 60 < U ≤ 120
III 50 < U ≤ 1 000 120 < U ≤ 1 500
IV    U > 1 000    U > 1 500
4.2 Connections between circuits
Circuits operating at different nominal voltages connected by power conversion equipment
which does not provide a conducting path between them, or circuits which are linked only by
a connection direct to the vehicle body external to the power conversion circuitry, shall be
individually classified at the nominal voltage of each circuit.

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If the conducting paths referred in this subclause include capacitive or inductive connections,
whose impedance is low enough to induce hazardous voltages into any circuit under either
normal or fault conditions, then all the circuits so connected shall be classified at the nominal
voltage of the highest voltage circuit.
NOTE  This condition can apply to circuits connected, for example, by means of a chopper converter with
impedance coupling.
Where circuits are linked conductively to a higher voltage source other than simply by circuit
bonds connected to the vehicle body (for example by an auto-transformer or potential
divider), all circuits in the group shall be treated as if energized at the nominal voltage of the
source, unless the conditions of 4.3 have been met.
4.3 Exceptions
If voltage conversion from one band to another involves overvoltage detection resulting in
disconnection of the primary or the secondary circuit, or having other means capable of
preventing excessive voltage in the secondary circuit, then the secondary circuit shall be
classified according to the highest voltage at which the detection equipment will operate.
NOTE 1  The integrity of the detection equipment should be taken into account.
Circuits not connected to the vehicle body, for example floating supplies, shall be classified
as appropriate in order to ensure that the requirements of this European Standard are met,
taking due account of the potentials possible in such circuits under normal or fault
conditions.
The limit between bands III and IV is allowed to be lowered to take account of special
national conditions.
NOTE 2  The above mentioned conditions are listed in annex A.
5 Protective provisions against direct contact
Live parts capable of causing an electric shock shall be protected against direct contact. All
types of equipment shall be capable of being operated without loss of protection against
direct contact. Protection against direct contact shall be provided by at least one of the
means described in 5.1 to 5.3, supplemented as necessary by warning labels as described
in 5.4.
5.1 Protection by insulation
In addition to the requirements of EN 50124-1, the insulating materials used to cover live
parts shall be appropriate to the nominal equipment operating voltage and the conditions of
use. Further provisions should be considered in order to minimize the consequences of
damage.
5.2 Protection by prevention of access
Access to live parts shall be prevented by placing them within closed electrical operating
areas or by placing them out of reach. The rest of this clause explains the measures
required.

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5.2.1 Voltages in bands I to III
5.2.1.1 Protection by the use of closed electrical operating areas
Live parts within the vehicle, energized with voltages in bands I to III shall be contained
within closed electrical operating areas.
Access to closed electrical operating areas containing energized live parts is permitted as
follows:
− band I and II: access is permitted to instructed persons and skilled persons;
− band III: access is only permitted to instructed persons and skilled persons provided that
all reasonably practicable precautions are taken against direct contact.
Prevention of access can be achieved either by mechanical locking or by physical
separation, supported by labels or procedures appropriate to the location and the equipment
enclosed.
Means of preventing access shall comply with the following:
− in areas within vehicles, accessible to ordinary persons, screens and covers shall conform
to the degree of protection IP4X as per EN 60529, or, where these are electrically
connected to the vehicle body, to the degree of protection IP2XD as per EN 60529. The
requirements of this subclause do not apply to plug connectors, lampholders without
lamps, fuse sockets for screw-in type fuses without inserts;
− in other areas where grid or mesh screens are used, these shall be placed at a sufficient
distance to prevent any direct contact, taking into account possible buckling or warping.
5.2.1.2 Protection by the use of electrical operating areas
Where the conditions of 5.2.1.1 do not apply, then live parts shall be contained within
electrical operating areas and the following shall apply:
− protection against direct contact is not required for live parts energized within bands I and
II, provided that these meet the requirements of clause 8;
− the use of obstacles to afford a limited protection against direct contact with live parts at
band III voltages may be acceptable in electrical operating areas inaccessible to ordinary
persons by their location (such as underframe cases, roofs, interiors of motor units,
excluding driver's cabs), provided that the hazard is readily identifiable. For example, it is
acceptable for fuses and isolating links of equipment at band III voltages, whose grips are
protected with an insulating material, not to be protected. Such units shall only be situated
in electrical operating areas.
5.2.1.3 Protection by clearance
For live parts on the outside of the vehicle (e.g. current collectors, roof conductors, resistors)
which are potentially accessible to persons in a straight line from any standing surface in, on
or by vehicles, protection against direct contact by means of clearance shall be provided if
no other protective measures as defined in this European Standard are used.
NOTE  Accessible in a straight line implies that live parts can be touched from a standing surface without use of
specially shaped objects.

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Protection by clearance is considered to be provided, if at least the clearances from standing
surfaces to live parts depicted in EN 50122-1, Figure 2 are maintained.
This protection is considered to be present, if contact with live parts is possible but clearance
is afforded by virtue of the movement of the vehicle (e.g. on road and foot-crossings). Where
only instructed persons and skilled persons have access and where operation of the system
makes protection by clearance impossible (e.g. systems using third and/or third and fourth
rail power supplies) protection shall be afforded by procedure.
5.2.1.4 Protection against hazards from power supply bus line
Access to live parts that may be energized with voltage band III when the supply system is
likely to be energized from an external source (e.g. another vehicle, preheating equipment,
shed supply, etc.) shall be prevented by an interlocking device or a procedure.
Connectors in the power supply bus line shall be fitted with warning labels in accordance
with 5.4.
5.2.2 Voltages in band IV
5.2.2.1 Protection by the use of closed electrical operating areas
Access to live parts energized with voltages in band IV shall be excluded to all persons
including skilled persons.
Access to live parts normally energized with voltages in band IV shall only be possible to
instructed persons and skilled persons after the live parts have been de-energized and made
safe by one or more of the following methods:
− procedure;
− interlocking devices;
− protective bonding;
− safety or monitoring devices.
Means of preventing access shall comply with the following:
− covers in areas accessible to ordinary persons in vehicles shall conform to the degree of
protection IP4X as per EN 60529;
− protection of equipment requiring infrequent intervention may consist of screwed or bolted
panels. It shall only be possible to remove these panels by use of a tool. No specific
locking system is thus required in these cases;
− for equipment requiring frequent intervention, interlocking devices shall be provided to
ensure that live parts become accessible only after their power supply has been cut off
and the live parts have been made safe by protective bonding. Locks and interlocking
devices shall allow off-load tests to be performed on control equipment.
In cases where band III voltages are not eliminated after band IV live parts have been de-
energized, the precautions of 5.2.1 shall be taken to prevent direct contact with live parts
which remain energized with voltages in band III.

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5.2.2.2 Protection by clearance
For live parts on the outside of the vehicle (e.g. current collectors, roof conductors, resistors)
as well as those of overhead line systems, which are potentially accessible to persons in a
straight line from fixed platforms as well as from any standing surface in, on or by vehicles,
protection against direct contact by means of clearance shall be provided if no other
protective measures as defined in this European Standard are used.
NOTE  Accessible in a straight line implies that live parts can be touched from a standing surface without use of
specially shaped objects.
Protection by clearance is considered to be provided, if at least the clearances from standing
surfaces to live parts depicted in EN 50122-1, Figure 14 are maintained.
5.2.2.3 Protection against hazards from power supply bus line
Access to live parts when the supply system is likely to be energized from an external source
(e.g. another vehicle, preheating equipment, shed supply, etc.) shall be prevented by an
interlocking device or procedure.
For equipment requiring frequent intervention, such as electric train supply jumpers,
interlocking devices or procedures shall be provided to ensure that the live parts of the
equipment become accessible only after their power supply has been cut off and the live
parts have been made safe by protective bonding.
Connectors in the power supply bus line shall be fitted with warning labels in accordance
with 5.4.
5.3 Protection by the use of band I
Where protective provisions in accordance with 5.1 or 5.2 are not possible, then protection
by the use of band I voltage can be provided in accordance with the conditions of 5.3.1 or
5.3.2 below.
5.3.1 Unbonded from a safe source
Where a circuit at a voltage in band I is not bonded to the vehicle body, no further protective
provision is required provided that the circuit meets the requirements of 411.1.2 (Sources for
SELV and PELV), 411.1.3 (Arrangements of circuits) and 411.1.4 (Requirements for
unearthed circuits) of HD 384.4.41 S2, as well as the requirements of clause 8 of this
European Standard.
5.3.2 Bonded from a safe source
Where a circuit at a voltage in band I is bonded to the vehicle body, no further protective
provision is required provided that the nominal voltage does not exceed 6 V A.C. or 15 V
D.C. and the circuit meets the requirements of 411.1.2 (Sources for SELV and PELV),
411.1.3 (Arrangements of circuits) and 411.1.5 (Requirements for earthed circuits) of
HD 384.4.41 S2. If the voltage exceeds 6 V A.C. or 15 V D.C., protection in accordance with
411.1 of HD 384.4.41 S2 is required only where ordinary persons have access.

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5.4 Warning labels
Warning labels especially for electrical hazards shall be in accordance with EN 61310-1
(WARNING: risk of electric shock).
If a hazard is considered to exist, after all interlocking devices or design features have been
operated to gain access to equipment, then warning labels shall be fitted to identify the
hazard and provide any supplementary information necessary to avoid danger to persons.
The labels shall be fitted in positions that ensure that they are clearly visible and will remain
so throughout the life of the equipment.
Access to elevated vehicle standing surfaces, from which live parts of a contact line system
can be reached, shall be marked by mean
...

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