Railway applications - Rail defects - Part 1: Rail defect management

This document specifies the defect management system the infrastructure manager uses to control the risk of severe accidents due to degradation of internal or surface defects on rails complying with EN 13674-1, EN 13674-2, EN 13674-4 and EN 15689:2009 (excluding grooved rails EN 14811 - which need alternative systems).

Bahnanwendungen - Schienenfehler - Teil 1: Handhabung von Schienenfehlern

Dieses Dokument legt das Fehlermanagementsystem fest, das Infrastrukturmanager verwenden, um das Risiko schwerer Unfälle aufgrund der Verschlimmerung von inneren oder Oberflächenfehlern an Schienen nach EN 13674 1, EN 13674 2, EN 13674 4 und EN 15689:2009 (mit Ausnahme von Rillenschienen nach EN 14811, die alternative Systeme benötigen) zu kontrollieren.

Applications ferroviaires - Défauts de rails - Partie 1 : Gestion des défauts de rails

Le présent document spécifie le système de gestion des défauts que le gestionnaire d'infrastructure utilise pour maîtriser le risque d'accidents graves dus à la dégradation des défauts internes ou de surface des rails conformes aux normes EN 13674 1, EN 13674 2, EN 13674 4 et EN 15689:2009 (à l'exception des rails à gorge EN 14811 — qui nécessitent d'autres systèmes).

Železniške naprave - Napake na progi - 1. del: Upravljanje železniških napak

General Information

Status
Published
Publication Date
24-Nov-2020
Withdrawal Date
30-May-2021
Current Stage
6060 - Definitive text made available (DAV) - Publishing
Start Date
25-Nov-2020
Due Date
17-Dec-2020
Completion Date
25-Nov-2020
Standard
EN 17397-1:2021 - BARVE
English language
69 pages
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Standards Content (Sample)


SLOVENSKI STANDARD
01-januar-2021
Železniške naprave - Napake na progi - 1. del: Upravljanje železniških napak
Railway applications - Rail defects - Part 1: Rail defect management
Bahnanwendungen - Schienenfehler - Teil 1: Handhabung von Schienenfehlern
Applications ferroviaires - Défauts de rails - Partie 1 : Gestion des défauts de rails
Ta slovenski standard je istoveten z: EN 17397-1:2020
ICS:
93.100 Gradnja železnic Construction of railways
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 17397-1
EUROPEAN STANDARD
NORME EUROPÉENNE
November 2020
EUROPÄISCHE NORM
ICS 93.100
English Version
Railway applications - Rail defects - Part 1: Rail defect
management
Applications ferroviaires - Défauts de rails - Partie 1 : Bahnanwendungen - Schienenfehler - Teil 1:
Gestion des défauts de rails Handhabung von Schienenfehlern
This European Standard was approved by CEN on 28 September 2020.

CEN 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 CEN-CENELEC Management Centre or to any CEN
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 CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 17397-1:2020 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 4
4 Abbreviations . 7
5 Defect management system . 7
5.1 General . 7
5.2 Defect types . 7
5.3 NDT inspection of rails . 7
5.4 Management of NDT inspection results . 8
6 Limits of rail condition . 8
6.1 General . 8
6.2 Definition of limits . 8
6.3 Rail defect immediate action limits L . 10
IA
7 Risk mitigation . 10
Annex A (informative) Description of rail defects . 11
A.1 Definition and description of rail defects . 11
A.2 Characterization of rail defects . 15
A.2.1 Transverse cracking . 15
A.2.2 Horizontal cracking . 19
A.2.3 Longitudinal vertical cracking . 25
A.2.4 Squat . 29
A.2.5 Head checks . 33
A.2.6 Other rail head surface conditions . 35
A.2.7 Corrosion . 50
A.2.8 Wear . 54
A.2.9 Other rail defects . 59
Annex B (informative) Immediate action limits L . 67
IA
Bibliography . 69

European foreword
This document (EN 17397-1:2020) has been prepared by Technical Committee CEN/TC 256 “Railway
applications”, the secretariat of which is held by DIN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by May 2021, and conflicting national standards shall be
withdrawn at the latest by May 2021.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
According to the CEN-CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
1 Scope
This document specifies the defect management system the infrastructure manager uses to control the
risk of severe accidents due to degradation of internal or surface defects on rails complying with
EN 13674-1, EN 13674-2, EN 13674-4 and EN 15689:2009 (excluding grooved rails EN 14811 — which
need alternative systems).
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 16729-3:2018, Railway applications - Infrastructure - Non-destructive testing on rails in track - Part 3:
Requirements for identifying internal and surface rail defects
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at https://www.iso.org/obp
3.1
plain rail
zone comprising all parts of the rail located away from the rail ends and the welding zones
3.2
rail end
part of the rail located within the length of the fishplates
3.3
welding zone
weld material itself plus 20 mm from each end of the weld collar (for aluminothermic welding and
electric arc welding) or upset (flash-butt welding)
Note 1 to entry: Any defect occurring in this zone is classified as a welding defect.
3.4
defective rail
rail which, for reasons of integrity or profile (including wear), requires management (examples in
Annex A)
3.5
damaged rail
rail which is neither cracked nor broken, but which has other defects
3.6
cracked area
part of the rail with a localized material discontinuity
3.7
broken rail
rail which has separated into two or more pieces (see Figure 1 and Figure 2) or any rail from which a
piece of metal becomes detached from the rail head, with a gap of more than 50 mm in length and more
than 10 mm in depth resulting in a running band less than 30 mm in width (see Figure 3)

Figure 1 — Example of a broken rail separated in two pieces

Key
l horizontal length
Figure 2 — Example of a broken rail with a gap at the rail end

Key
a vertical depth
l horizontal length
c non-cracked area
Figure 3 — Example of a broken rail with a gap
3.8
rail surface defect
defect which initiates on any of the surfaces of the rail
3.9
rail head surface defect
defect which initiates on or within 5 mm from the running surface of the rail
3.10
rail internal defect
defect which initiates from within the rail section but may grow to become visible on the rail surface
3.11
NDT Method
discipline applying a physical principle in non-destructive testing
[SOURCE: EN 13938-5:2004, definition 3.2]
EXAMPLE: Ultrasonic testing.
3.12
wheel/rail interaction
effect of rolling and sliding contact and direct forces from the vehicle wheels which can cause damage to
the rail
3.13
environmental degradation
damage to the rail caused by external environmental factors
3.14
geometrical planes of the rail
see EN 16729-3:2018, 3.10, Figure 4
3.15
infrastructure manager [IM]
body or organisation responsible in particular for establishing and maintaining railway infrastructure,
as well as for operating the control and safety systems
3.16
track maintenance engineer [TME]
engineer with “safety of line” responsibility for a defined track area
4 Abbreviations
For the purposes of this document, the following abbreviations apply.
Abbreviation Definition
RDM rail defect management
S&C switches and crossings
TME track maintenance engineer
IM infrastructure manager
NDT non-destructive testing
CWR continuously welded rail
RAMS reliability, availability, maintainability, safety
LCC life cycle costs
5 Defect management system
5.1 General
An infrastructure manager shall put a framework in place to monitor the condition of its assets. If the
infrastructure becomes deteriorated, it needs to be renewed or repaired. This can be for economic
reasons or, typically at a later state in the development and propagation of the defect, due to safety
reasons.
5.2 Defect types
There are a wide variety of rail defects that lead to damaged or defective rail. These defects can be
grouped and categorized by a system.
The classification of the defect types along with the internationally widely used numbering scheme can
be found in the Annex A of this document.
5.3 NDT inspection of rails
The IM shall implement a testing framework (appropriate NDT methods and inspection frequencies) to
inspect rail to detect the defects considered relevant by the IM. The testing frequency should be
designed to mitigate the risk that a detectable defect propagates to a critical size leading to failure.
The standard EN 16729-3:2018 describes how several of the most relevant defects can be detected
using various methods of NDT.
5.4 Management of NDT inspection results
Actions shall be taken depending on the results of the inspection. Several limits can exist that lead to
different actions. Immediate action has to be taken, if the defect has reached a safety critical size.
Smaller detected defects shall be managed (by repair or removal) to prevent them from reaching a
safety critical size.
The infrastructure manager shall record the lifecycle of each defect from detection, monitoring, to
removal.
6 Limits of rail condition
6.1 General
A methodology to analyse rail condition should take into account the economic optimum of reliability,
availability, maintainability, safety (RAMS) and life cycle costs (LCC). Different infrastructure managers
have different limits for these economic factors, based on various boundary conditions.
The larger a defect grows, the greater becomes the safety risk and this has to be balanced against the
economic limits. The urgent removal of a safety critical defect is usually not the most cost-effective
action with regards to LCC.
6.2 Definition of limits
A typical degradation curve is shown in Figure 4, together with an example of various limits for
intervention.
Key
C Current condition of the rail
C0 Basic condition, this is the condition at which new rail is accepted after the installation in track. Due to
the constant usage of the rail, the condition starts to deteriorate.
L Start of economic maintenance limit, when reaching or exceeding the limit L actions such as rail
E_start E_start
reprofiling or repair welding can be considered to improve the condition of the rail and extend its
service live.
LE_end End of economic maintenance limit, at this condition the economic maintenance of the rail has been
expended. Actions to improve the condition of the rail are no longer feasible. Further use of the rail is
possible. Planning of rail replacement is advised to avoid that the rail reaches a critical condition.
LI Intervention limit, intervention limit refers to the value which, if exceeded, requires corrective
maintenance in order that the immediate action limit shall not be reached before the next inspection.
L Immediate action limit, the condition of the rail has reached the limit of concern with regard to the
IA
structural integrity of the rail. The condition considers an operational risk and the rail does no longer
allow for safe and unlimited traffic. Corrective maintenance actions shall be executed as soon as
practical, normally within a fixed time limit set by the IM. In the meantime, temporary measures shall
be considered to mitigate the risks until the rail can be replaced.
LC Critical limit, rail of this condition is a high risk and rail traffic shall be suspended immediately until a
full risk assessment has been undertaken by the track maintenance engineer or the rail has been
repaired or replaced.
F Failure of the rail (e.g. rupture)
AE Area of economic maintenance
t Time
Figure 4 — Degradation curve of the rail over the service life
6.3 Rail defect immediate action limits L
IA
Informative immediate action limits L for the most common types of rail defects can be found in
IA
Annex B. The IM may define more stringent limits based upon performance and overall risk
management of the infrastructure.
Some defect types do not directly lead to cracks growing in the rail, but will affect the performance of
the track system and need to be removed. For these defect types, end of economic maintenance limits
L is typically used. One example is corrugation, where the values presented in EN 13231-5:2018
E_end
represent end of economic maintenance limits L .
E_end
7 Risk mitigation
Risk management starts with the implementation of the track-testing framework, develops on the
detection of a defect and ends with the actual removal of the defect. Upon detecting a rail defect and
based on the actual circumstances in the track, a variety of measures should be considered in order to
mitigate the risk of failure before the rail can be changed:
— reducing line speed;
— mounting fishplates, if feasible for that type of defect;
— increase the frequency of inspection, up to constant surveillance;
— restriction of the use for special types of railway vehicles;
— closing the track.
Several factors other than defect type and size shall be taken into account when assessing the risks that
defects have on the structural integrity of the rail:
— line speed, category and type of traffic;
— multiple isolated defects within a short distance or cluster density of defects over longer length;
— expected crack growth until removal;
— location of the defect site in the track;
— track condition including geometry;
— rail profile and current condition such as wear and corrosion;
— steel grade;
— manufacturing process;
— accumulated tonnage;
— site history;
— low rail temperatures causing tensile stress in the rail of continuously welded track.
Annex A
(informative)
Description of rail defects
A.1 Definition and description of rail defects
The general coding system for rail defects and the classification of the different types of defect are
shown in Table A.1.
The codes in Table A.1 apply to vignole rail only.
Table A.1 — Rail defect coding system
1st digit 2nd digit 3rd digit 4th digit
Situation Location Pattern, nature
0. Unknown origin
1. Transverse
2. Horizontal
0. Full section
3. Longitudinal vertical
1. Rail head
4. Corrosion
3. Web
5. Passing through a
5. Foot hole
6. Not passing through
Additional
a hole
characteristics and
9. Lap
1. Rail ends
differentiations
0. Wear
2. Plain rails
1. Rolling Surface
defects
2. Gauge corner defects
3. Crushing
2. Surface of rail head
4. Local batter
5. Wheel burns
7. Cracking and local
subsidence of the
running surface
8. Dripping water
Situation Location Origin, cause (No 4th digit)
1. Bruising
3. Defects caused by
2. Faulty machining
0. Full section
damage to rail
3. Permanent
deformation
1st digit 2nd digit 3rd digit 4th digit
Situation Welding method Pattern, nature
1. Electric flash-butt
welding
2. Aluminothermic
welding
1. Transverse
3. Electric arc welding
2. Horizontal or Additional
4. Welding and 4. Oxyacetylene shelling
characteristics
resurfacing (autogenous) welding
5. Wheel burns
and differentiations
defects 5. Pressurized gas
7. Cracking and local
welding
subsidence of the
6. Induction welding running surface
7. Resurfacing
8. Other welding
methods
Numbering of rail defects.
Each rail defect is assigned a number shown in Table A.2.
Table A.2 — Numbering of rail defects
1 Defects in rail ends
11/12 Head
111 Transverse cracking
112 Horizontal cracking
113 Longitudinal vertical cracking
114 Corrosion
121 Surface defects
1211 Spalling
1212 Long groove
1213 Rolling lap
122 Shelling of running surface
1221 Flaking
1222 Shelling
1223 Head checking
123 Crushing
124 Local batter of running surface
125 Isolated wheel burn
127 Squat, cracking and local depression of the running surface
13 Web
132 Horizontal cracking
1321 at the web-head fillet radius
1322 at the web-foot fillet radius
133 Longitudinal vertical cracking (piping)
134 Corrosion
135 Cracking of fishbolt holes
139 Lap
15 Foot
153 Longitudinal vertical cracking
154 Corrosion
2 Defects in plain rails
20 Full section
200 Transverse break without identified origin
21/22 Head
211 Transverse cracking
212 Horizontal cracking
213 Longitudinal vertical cracking
214 Corrosion
220 Wear
2201 Short-pitch corrugation
2202 Short-wave and long-wave corrugation
2203 Excessive lateral wear
2204 Excessive vertical wear
221 Running surface defects
2211 Spalling
2212 Long groove
2213 Rolling lap
222 Gauge corner defects
2221 Flaking
2222 Shelling
2223 Head checking
223 Crushing
224 Local batter of the running surface
225 Wheelburn
2251 Isolated wheelburn
2252 Multiple wheelburns
227 Squat, cracking and local depression of the running surface
Local depression of the running surface caused by dripping water in
tunnels
23 Web
232 Horizontal cracking
2321 at the web-head fillet radius
2322 at the web-foot fillet radius
233 Longitudinal vertical cracking (piping)
234 Corrosion
235 Cracking around holes other than fishbolt holes
236 Diagonal cracking
239 Lap
25 Foot
251 Transverse fracture of machined rail
253 Longitudinal vertical cracking
254 Corrosion
3 Defects caused by damage to the rail
30 Full section
301 Bruising
302 Faulty machining
303 Permanent deformation
4 Welding and resurfacing defects
41 Electric flash-butt welding
411 Transverse cracking of the profile
412 Horizontal cracking of the web
417 Squat, cracking and local depression of the running surface
42 Alumino-thermic welding
421 Transverse cracking of the profile
422 Horizontal cracking of the web
427 Squat, cracking and local depression of the running surface
43 Electric arc welding
431 Transverse cracking of the profile
432 Horizontal cracking of the web
437 Squat, cracking and local depression of the running surface
47 Resurfacing
471 Transverse cracking of the rail head
472 Detachment or shelling of the resurfaced portion
48 Other welding methods
481 Transverse cracking in rail from electrical connection
A.2 Characterization of rail defects
A.2.1 Transverse cracking
A.2.1.1 General
Table A.3 — Transverse cracking
Defect type
Transverse cracking
Code-numbers and names
111 Transverse cracking
211 Transverse cracking
411 Transverse cracking in electric flash-butt welds
421 Transverse cracking in alumino-thermic welds
431 Transverse cracking in electric arc welds
A.2.1.2 Appearance, causes and location - Transverse cracking
Table A.4 — Transverse cracking
Transverse cracking (111 / 211)
Transverse cracking initiates in the central of the rail head or in the gauge corner area.
It is a manufacturing defect caused by internal inclusions or hydrogen micro cracks. Impact loads are
crack developing factors.
When a rail break occurs before the defect becomes visible, a smooth, shiny kidney-shaped patch can
be observed.
When the crack reaches the surface of the railhead the surface of the crack starts to oxidize. Railbreak
is imminent at this stage.
Not to be confused with transverse cracking from the rail head surface, e.g. head checks or shelling, or
with transverse cracking under resurfacing (471), or with transverse crack on welds (411).
Figure A.1 — 211 – Central origin

Figure A.2 — 211 – Origin in the gauge corner area
Table A.5 — Transverse cracking in welds
Transverse cracking in welds (411 / 421 / 431)
Transverse cracking in welds initiates in electric flash-butt welds, in aluminothermic welds and
electric arc welds.
It is a manufacturing defect caused by welding design and process or by internal inclusions.
Not to be confused with sudden arcing near the weld, e.g. bruising (301).

Figure A.3 — 411 – Internal defect of the head in the weld

Figure A.4 — 421 – Internal defect of the foot in the weld
Figure A.5 — 421 – Crack located largely in the vertical plane

Figure A.6 — 421 – Break from crack in the vertical plane in the weld
Figure A.7 — 431 – Transverse cracking of the profile in electric arc joint weld
A.2.2 Horizontal cracking
A.2.2.1 General
Table A.6 —Horizontal cracking
Defect type
Horizontal cracking
Code-numbers and names
112 Horizontal cracking in the head at rail end
132 Horizontal cracking in the web at rail end
1321 Horizontal cracking in the web-head fillet radius at rail end
1322 Horizontal cracking in the web-foot fillet radius at rail end
212 Horizontal cracking in the head in plain rail
232 Horizontal cracking in the web in plain rail
2321 Horizontal cracking in the web-head fillet radius in plain rail
2322 Horizontal cracking in the web-foot fillet radius in plain rail
412 Horizontal cracking in the web in electric flash-butt weld
422 Horizontal cracking in the web in alumino-thermic weld
432 Horizontal cracking in the web in electric arc weld
A.2.2.2 Appearance, causes and location
A.2.2.2.1 Horizontal cracking in the head
Table A.7 — Horizontal cracking in the head
Horizontal cracking in the head (112 / 212)
Horizontal cracking in the head initiates in the railhead and progresses parallel to the running
surface.
Development is accelerated by impact loads at joints of poor conditions.
It may result in local depression of the running surface, which may be characterized by a dark patch
contrasting with the shiny surface of the running band.
A small crack appears on one or both faces of the head and on the end face in the gap of the expansion
joint.
It may be accompanied by a vertical crack or progress into a transverse crack. At a later stage, a piece
of metal may break away.
Not to be confused with longitudinal vertical cracking or with shelling (2222) of running surface.

Figure A.8 — 212 – Horizontal cracking in the head of plain rails
Figure A.9 — 212 – Horizontal cracking in the head of plain rails with a transverse crack growth

Figure A.10 — 212 – Horizontal cracking in the head in plain rail
A.2.2.2.2 Horizontal cracking in the web
Table A.8 — Horizontal cracking in the web
Horizontal cracking in the web (132 / 1321 / 1322 / 232 / 2321 / 2322)
Horizontal cracking in the web initiates at any position of the web.
It is a manufacturing defect if initiation in plain rail.
Initiation at rail end is caused by stresses between the fishplate and the rail due to the vertical
movement of the joint under passing trains caused by poor track geometry, joint quality or incorrect
fish plating and will separate the head or the foot from the web.
It progresses parallel to the running surface and may curve either upwards or downwards causing
the head or the foot to break away or fragmentation of the rail.
Not to be confused with Cracking of holes (135, 235) in the cases where it develops through a hole.

Figure A.11 — 1321 – Horizontal cracking in the web-head fillet

Figure A.12 — 1321 – Horizontal cracking in the web – head fillet
Figure A.13 — 2321 – Horizontal cracking at the web-head fillet radius
A.2.2.2.3 Horizontal cracking of the web in welds
Table A.9 — Horizontal cracking of the web in welds
Horizontal cracking of the web in welds (412 / 422 / 432)
Horizontal cracking of the web in welds initiates at any position of the web in welds.
It is a manufacturing defect caused by welding design and process or by internal inclusions. It can be
influenced by boltholes too close to the weld.
It progresses parallel to the running surface and may curve either upwards and/or downwards
causing the head or the foot to break away or fragmentation of the rail.

Figure A.14 — 422 – Horizontal cracking of the web in an alumino-thermic weld
Figure A.15 — 422 – Horizontal cracking of the web in an alumino-thermic weld

Figure A.16 — 422 – Horizontal cracking in the web in an alumino-thermic weld
A.2.3 Longitudinal vertical cracking
A.2.3.1 Longitudinal vertical cracking of the head
Table A.10 — Longitudinal vertical cracking of the head
Defect type
Longitudinal vertical cracking of the head
Code-numbers and names
113 Longitudinal vertical cracking of the head in rail ends
213 Longitudinal vertical cracking of the head in plain rails
Appearance, causes and location
Longitudinal vertical cracking of the head (113 / 213)
Longitudinal vertical cracking of the head initiates at several locations throughout the length of the
rail and may propagate through a weld.
It is a manufacturing defect, caused by inclusions rolled into the rail predominantly made by the ingot
casting process. It progresses parallel to the rail web and tends to divide the rail head gradually into
two parts. As it progress it may be visible on different locations: as a black line on the surface when it
reaches the running surface, a depression of the running surface and a widening of the rail head
corresponding to the opening of the crack, or as a bright line or a crack in the web-head fillet radius
on either side of the web.
Not to be confused with rolling lap (1213, 2213).

Figure A.17 — 213 – Longitudinal vertical crack visible along the rail top surface a)
Figure A.18 — 213 – Longitudinal vertical crack
...

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