Space engineering - Environmental control and life support (ECLS)

EN 16603-34 addresses the discipline of environmental control and life support (ECLS) and the interfaces to other disciplines of engineering and to the domains of management and product assurance. It also introduces the structure and applicability of the associated Level 3 Standards. The environmental control and life support systems (ECLSS) covered in this Standard includes those aspects relating to the assurance of a safe and comfortable environment for human beings undertaking a space mission. When other forms of life are accommodated on board, the ECLSS also ensures the appropriate environmental conditions for those living organisms. This Standard applies to all ECLSS for: - all manned space endeavours and manrated space products, and - any other form of life to be maintained on board. This standard may be tailored for the specific characteristics and constrains of a space project in conformance with ECSS-S-ST-00.

Raumfahrttechnik - Umweltkontrolle und Lebenserhaltung (ECLS)

Ingénierie spatiale - Contrôle de l'environnement et support de vie pour les vols habités

Vesoljska tehnika - Nadzorovanje okolja in omogočanje življenja

Standard EN 16603-34 obravnava disciplino nadzorovanja okolja in omogočanja življenja (ECLS) ter povezave do drugih disciplin inženirstva in področij upravljanja ter varnih proizvodov. Uvaja tudi strukturo in uporabnost povezanih standardov 3. ravni. Sistemi za nadzorovanje okolja in omogočanje življenja (ECLSS), zajeti v tem standardu, vključujejo vidike, povezane z zagotavljanjem varnega in udobnega okolja za človeka na vesoljski misiji. Če se na krovu nahajajo tudi druge oblike življenja, sistemi za nadzorovanje okolja in omogočanje življenja zagotavljajo ustrezne okoljske razmere tudi za te žive organizme. Ta standard velja za vse sisteme za nadzorovanje okolja in omogočanje življenja za: - vse vesoljske projekte s človeško posadko in vesoljske izdelke, primerne za ljudi, ter - katero koli drugo obliko življenja, ki bo živela na krovu. Ta standard se lahko prilagodi posameznim lastnostim in omejitvam vesoljskega projekta v skladu s standardom ECSS-S-ST-00.

General Information

Status
Published
Publication Date
22-Oct-2014
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
05-Sep-2014
Due Date
10-Nov-2014
Completion Date
23-Oct-2014

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Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 16603-34:2014
01-november-2014
9HVROMVNDWHKQLND1DG]RURYDQMHRNROMDLQRPRJRþDQMHåLYOMHQMD
Space engineering - Environmental control and life support (ECLS)
Raumfahrttechnik - Umweltkontrolle und Lebenserhaltung (ECLS)
Ingénierie spatiale - Contrôle de l'environnement et support de vie pour les vols habités
Ta slovenski standard je istoveten z: EN 16603-34:2014
ICS:
13.020.99 Drugi standardi v zvezi z Other standards related to
varstvom okolja environmental protection
49.140 Vesoljski sistemi in operacije Space systems and
operations
SIST EN 16603-34:2014 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 16603-34:2014

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SIST EN 16603-34:2014


EUROPEAN STANDARD
EN 16603-34

NORME EUROPÉENNE

EUROPÄISCHE NORM
August 2014
ICS 49.140

English version
Space engineering - Part 34: Environmental control and life
support (ECLS)
Ingénierie spatiale - Partie 34: Contrôle de l'environnement Raumfahrttechnik - Teil 34: Umweltkontrolle und
et support de vie pour les vols habités Lebenserhaltung (ECLS)
This European Standard was approved by CEN on 23 February 2014.

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

CEN and CENELEC members are the national standards bodies and national electrotechnical committees of Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece,
Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia,
Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.






CEN-CENELEC Management Centre:
Avenue Marnix 17, B-1000 Brussels
© 2014 CEN/CENELEC All rights of exploitation in any form and by any means reserved Ref. No. EN 16603-34:2014 E
worldwide for CEN national Members and for CENELEC
Members.

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SIST EN 16603-34:2014
EN 16603-34:2014 (E)
Table of contents
Foreword . 5
1 Scope . 6
2 Normative references . 7
3 Terms, definitions and abbreviated terms . 8
3.1 Terms from other standards . 8
3.2 Terms specific to the present standard . 8
3.3 Abbreviated terms. 10
4 Requirements . 11
4.1 Overview . 11
4.2 Mission and system . 11
4.2.1 General . 11
4.2.2 Mission . 11
4.2.3 System . 12
4.3 General . 13
4.3.1 Forms of life . 13
4.3.2 ECLSS engineering . 14
4.3.3 Environmental condition . 14
4.4 Functional . 14
4.4.1 Overview . 14
4.4.2 Maintain environment . 15
4.4.3 Respond to environmental contingencies . 20
4.4.4 Provide resources . 22
4.4.5 Manage waste . 27
4.4.6 Support EVA operations . 30
4.4.7 Provide health related services . 32
4.5 Design . 33
4.5.1 Overview . 33
4.5.2 Data management control . 33
4.6 Interface . 34
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4.6.1 General . 34
4.6.2 Ground support equipment (GSE) . 34
4.6.3 Mission interfaces . 34
4.7 Verification . 36
4.7.1 General . 36
4.7.2 Verification by similarity . 37
4.7.3 Verification by inspection. 37
4.7.4 Verification by analysis . 37
4.8 Product assurance and safety . 37
4.9 Deliverables . 38
4.9.1 Hardware . 38
4.9.2 Documentation . 38
Annex A (informative) Parameters specification and monitoring . 39
A.1 Specification of parameters . 39
A.2 Monitoring of parameters . 42
Annex B (informative) Reference information for parameters . 43
B.1 Previous flight data . 43
B.2 ISS data . 49
B.2.1 Atmosphere. 49
B.2.2 ECLS loads . 50
B.2.3 Water quality . 51
B.2.4 Radiation doses . 52
Annex C (informative) References . 54
Bibliography . 55

Tables
Table 4-1: Classification of pressurized volume . 15

Table A-1 : List of parameters to be specified . 39
Table A-2 : List of parameters to be monitored . 42
Table B-1 : Previous flight data . 44
Table B-2 : American programmes - Requirements . 45
Table B-3 : American programmes - Functions . 46
Table B-4 : Russian programmes - Requirements . 47
Table B-5 : Russian programmes - Functions . 48
Table B-6 : Atmosphere data . 49
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Table B-7 : Metabolic loads . 50
Table B-8 : Water quality specifications . 51
Table B-9 : Current ionizing radiation equivalent dose limits . 52
Table B-10 : Organ dose limits for deterministic effects (all ages) . 52
Table B-11 : Current career exposure limits . 53

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SIST EN 16603-34:2014
EN 16603-34:2014 (E)
Foreword
This document (EN 16603-34:2014) has been prepared by Technical Committee
CEN/CLC/TC 5 “Space”, the secretariat of which is held by DIN.
This standard (EN 16603-34:2014) originates from ECSS-E-ST-34C.
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 February
2015, and conflicting national standards shall be withdrawn at the latest by
February 2015.
Attention is drawn to the possibility that some of the elements of this document
may be the subject of patent rights. CEN [and/or CENELEC] shall not be held
responsible for identifying any or all such patent rights.
This document has been prepared under a mandate given to CEN by the
European Commission and the European Free Trade Association.
This document has been developed to cover specifically space systems and has
therefore precedence over any EN covering the same scope but with a wider
domain of applicability (e.g. : aerospace).
According to the CEN-CENELEC Internal Regulations, the national standards
organizations of the following countries are bound to implement this European
Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic,
Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,
Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United
Kingdom.
5

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SIST EN 16603-34:2014
EN 16603-34:2014 (E)
1
Scope
This Standard addresses the discipline of environmental control and life
support (ECLS) and the interfaces to other disciplines of engineering and to the
domains of management and product assurance.
It also introduces the structure and applicability of the associated Level 3
Standards.
The environmental control and life support systems (ECLSS) covered in this
Standard includes those aspects relating to the assurance of a safe and
comfortable environment for human beings undertaking a space mission.
When other forms of life are accommodated on board, the ECLSS also ensures
the appropriate environmental conditions for those living organisms.
This Standard applies to all ECLSS for:
• all manned space endeavours and man-rated space products, and
• any other form of life to be maintained on board.
This standard may be tailored for the specific characteristics and constrains of a
space project in conformance with ECSS-S-ST-00.

6

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EN 16603-34:2014 (E)
2
Normative references
The following normative documents contain provisions which, through
reference in this text, constitute provisions of this ECSS Standard. For dated
references, subsequent amendments to, or revision of any of these publications,
do not apply. However, parties to agreements based on this ECSS Standard are
encouraged to investigate the possibility of applying the more recent editions of
the normative documents indicated below. For undated references, the latest
edition of the publication referred to applies.

EN reference Reference in text Title
EN 16601-00-01 ECSS-S-ST-00-01 ECSS system— Glossary of terms
EN 16003-10-02 ECSS-E-ST-10-02 Space engineering — Verification

7

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3
Terms, definitions and abbreviated terms
3.1 Terms from other standards
For the purpose of this Standard, the terms and definitions from
ECSS-S-ST-00-01 apply.
3.2 Terms specific to the present standard
3.2.1 anoxic
gas or atmosphere containing no oxygen
3.2.2 closed-loop ECLSS
ECLSS based on recycling, regeneration, and recovery of materials or elements
NOTE The closed-loop ECLSS implies that the use of
significant expendables and consumables is
excluded from the processes.
3.2.3 compression
EVA related action to increase total pressure
3.2.4 decompression
EVA related action to reduce the total pressure
3.2.5 depressurization
action to reduce the total pressure
3.2.6 environmental control and life support (ECLS)
engineering discipline dealing with the physical, chemical and biological
functions to provide humans and other life forms with suitable environmental
conditions
NOTE The objective of ECLS is to create a suitable
environment by controlling the environmental
parameters, providing resources, and managing
waste products.
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3.2.7 environmental control and life support system (ECLSS)
system that includes the hardware and software to perform ECLS functions
3.2.8 hypoxic
gas or atmosphere containing oxygen that provides a partial pressure of oxygen
below the specified range of oxygen partial pressure in the atmosphere of
habitable volumes
3.2.9 open-loop ECLSS
ECLSS based on external resupply of resources
3.2.10 partial pressure
participation of one of the constituents of a gas mixture or an atmosphere in the
total pressure
NOTE 1 Examples include:
• PCO2, stands for partial pressure of carbon
dioxide,
• PH2O, stands for water vapour partial pressure.
NOTE 2 To calculate a partial pressure, the fraction of the
constituent is multiplied by the total pressure. For
example, the partial pressure of oxygen on Earth
is:
6 6
PO2 = 0,21 × 1,013 × 10 Pa = 0,213 × 10 Pa.
NOTE 3 Abbreviation for partial pressure is P followed by
the chemical formula of the constituent.
3.2.11 pressurization
action to increase the total pressure
3.2.12 re-compression

EVA related action to restore the total pressure after decompression or to treat
decompression illness
3.2.13 re-compression

action to restore the total pressure after depressurization
3.2.14 re-pressurization
action to restore the total pressure after depressurization
3.2.15 safe haven
facility capable of sustaining human life under emergency conditions as a
minimum, in the case of a life threatening situation
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3.3 Abbreviated terms
For the purpose of this Standard, the abbreviated terms from ECSS-S-ST-00-01
and the following apply:

Abbreviation Meaning
colony forming unit
CFU
decompression illness
DCI
environmental control and life support
ECSL
ECLS system
ECLSS
engineering model
EM
electromagnetic compatibility
EMC
EVA mobility unit
EMU
extra-vehicular activity
EVA
failure detection, isolation and recovery
FDIR
flight model
FM
field of view
FOV
ground support equipment
GSE
interface control document
ICD
International Space Station
ISS
intra-vehicular activity
IVA
more than 1-g acceleration situation
multi­g
qualification model
QM
spacecraft maximum allowable concentration
SMAC
thermal control system
TCS

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EN 16603-34:2014 (E)
4
Requirements
4.1 Overview
Requirements defined in this Standard are specific to ECLSS, including
requirements for functional objectives of the system or requirements for the
safety of life.
Requirements are not quantified with values for the parameters. Quantified
specifications are established on a case-by-case basis for project dependent
items. Examples of parameters to be specified are listed in Annex A
4.2 Mission and system
4.2.1 General
a. The ECLSS shall be designed for a specific mission and all phases within
that mission as defined in 4.2.2, up to the end of the operational lifetime.
4.2.2 Mission
4.2.2.1 Overview
Basic requirements on the ECLSS vary according to the mission scenarios and
the mission phases of the selected mission. The most important parameters
affecting the requirements are the mission duration, the size of the crew, the
type and quantity of living organisms, the availability of a source of resupply
(e.g. Earth and space cargo) and the feasibility or duration of any saving, rescue
or evacuation procedure.
The longer the mission duration and the larger the distance from the source of
resupply (e.g. Earth) are the more difficult the rescue becomes and the higher
the dependence is on ECLSS closed loops.
4.2.2.2 Identification of requirements
a. ECLSS requirements related to each mission phase shall be identified in
project Phase A.
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EN 16603-34:2014 (E)
NOTE For project phases and planning, see
ECSS-M-ST-10.
4.2.2.3 Mission phases
a. The applicable conditions for the following mission phases shall be
included in the ECLSS definition:
1. ground and pre-launch operations;
(a) storage, transport;
(b) functional check out;
(c) waiting on launch pad.
2. launch and ascent;
(a) launch time;
(b) external environment;
(c) specific requirements during multi-g phases;
(d) impact of depressurization and re-pressurization (IVA);
(e) launch abort situation.
3. planetary orbital phase;
4. transfer phase;
5. docking, docked and separation phases, rendezvous and parking;
6. extra-vehicular activity: pre-breathing
7. planetary phase;
(a) landing, mission on planet;
(b) planetary walk;
(c) excursion, rover, supported excursion.
8. return to Earth, descent, reentry and landing;
9. post landing phases, quarantine.
NOTE Manned and unmanned phases can be part of a
given mission.
b. The storage and transport conditions for supplies shall be specified.
c. External environmental conditions, both on ground and in space shall be
taken into account.
4.2.3 System
4.2.3.1 Multi-ECLSS phases
4.2.3.1.1 Applicability
The requirements in 4.2.3.1.2 apply to each of the several pressurized volumes
that can be involved in a given mission, each with its own ECLSS to work
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independently during some phases of the mission, for the duration of the
independent operations (example EVA suit).
4.2.3.1.2 Requirements
a. Interfaces shall be defined for the period of time when several
pressurized volumes having independent ECLSSs are mated.
b. When an ECLSS is not in operation during a given phase of the mission,
standby mode conditions shall be defined.
c. When docking to another spacecraft, the various ECLSSs involved shall
be compatible.
4.2.3.2 Reusable systems
a. When a vehicle is used for several missions, the following issues shall be
addressed during the design phase (project Phase B):
1. standby, storage and parking conditions between missions;
2. recommissioning procedure before next mission.
4.3 General
4.3.1 Forms of life
4.3.1.1 Humans
The ECLSS can be designed for a mixed or an unmixed crew.
For human factors such as metabolism and anthropometrics, see
ECSS-E-ST-10-11.
4.3.1.2 Forms of life other than humans
4.3.1.2.1 Metabolism
a. Requirements for energy and for overall intake and output of
consumables shall be defined at the beginning of the ECLSS development
programme (project Phase A).
4.3.1.2.2 Environmental conditions
a. Environmental conditions for the forms-of-life to support shall be defined
at the beginning of the programme (project Phase A).
NOTE It is important to define such environmental
condition because it is usually form of life
dependent.
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4.3.2 ECLSS engineering
4.3.2.1 Humans
a. In engineering of the ECLSS for human missions, the following system
modes of operation shall be defined:
1. nominal,
2. degraded, and
3. emergency.
NOTE Environmental conditions for each mode are based
on the threshold limit values of the concerned
parameters.
b. In the case that, in emergency mode, the mission cannot be aborted to
ensure a safe return to Earth, the crew shall have the capability to restore
(at least) the state of degraded mode without external resources for the
remaining duration of the mission eventually by entering safe haven.
NOTE Some missions can include low orbital flights
where abortion of the mission is a feasible scenario
for emergency rescue.
4.3.2.2 Forms of life other than humans
a. For forms of life other than human, requirements shall
1. define the environment suitable for the forms of life to be
supported, and
2. take into account the potential interference with the human
mission requirements.
4.3.3 Environmental condition
a. The variation in the parameters defining the human natural and imposed
environment, shall be taken into account during project Phase A.
NOTE Examples of such parameters are gravity, pressure,
atmosphere composition and ionizing radiation.
4.4 Functional
4.4.1 Overview
The functions defined in this clause 4.4 are part of the general tailoring of the
ECLSS requirements for a given project.
The functional requirements defined in 4.4.2 to 4.4.6 are applicable to human
missions. For other forms of life, relevant requirements can be obtained by
tailoring them.
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4.4.2 Maintain environment
4.4.2.1 General
a. To support and maintain health, safety and well being, the ECLSS shall
maintain the nominal environmental conditions in the pressurized
volume.
NOTE Classification of pressurized volume is given in
Table 4-1.
Table 4­1: Classification of pressurized volume
Accessible volume
Non­accessible Non­habitable
volume Habitable volume volume
Definition Volume that humans Volume that humans Volume that humans
cannot enter, even can freely enter can enter, only with
with dismounting preventive
operations dismounting
operations.
Examples Within a component Cabin Behind racks, panels,
Crew quarter floor or ceiling which
can be removed
4.4.2.2 Control atmosphere total pressure
4.4.2.2.1 Total atmospheric pressure
a. The nominal value and the limit values for the total atmospheric pressure
in the pressurized volume shall be specified.
4.4.2.2.2 Monitor atmosphere total pressure
a. The range and the accuracy to monitor the atmosphere total pressure in
the pressurized volume shall be specified.
4.4.2.2.3 Means for adjusting pressure
a. Means for adjusting pressure at the selected value (up or down) inside
the specified range applicable for each type of pressurized volume shall
be provided.
4.4.2.2.4 Prevent over-pressurization
a. Over-pressurization shall be prevented.
4.4.2.2.5 Equalize atmosphere pressure
a. The capability to equalize the maximum pressure differential, as defined
by the pressure control range, between adjacent, isolated pressurized
volumes shall be provided.
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4.4.2.2.6 Add inert diluent gas to atmosphere
a. Addition of inert diluent gas (for example nitrogen) into the pressurized
volume shall be provided at a rate capable of maintaining the
atmospheric pressure within the control range.
b. Addition of inert diluent gas (for example nitrogen) into the atmosphere
shall be provided at a rate capable of atmospheric restoration after
decompression of the habitable volume.
c. When adding inert diluent gas (for example nitrogen) into the
atmosphere the levels of anoxic or hypoxic zones in the accessible
volume shall be specified.
d. The limits for pressure adjustments, decompression, compression and
re-compression shall be specified.
e. Means to manage pressure change rates within the specified limits shall
be provided.
4.4.2.2.7 Add oxygen to atmosphere
a. Addition of gaseous oxygen into the atmosphere shall be provided at a
rate capable of maintaining the oxygen partial pressure in the accessible
volume within the specified range.
b. Addition of gaseous oxygen into the atmosphere shall be provided at a
rate capable of restoring the atmospheric condition after decompression
of the accessible volume.
c. Addition of oxygen shall not create risk of fire.
4.4.2.3 Control thermal nominal condition
4.4.2.3.1 Maintain thermal nominal condition:
a. The limits of the atmosphere effective temperature in the habitable
volume shall be specified.
NOTE The atmosphere effective temperature is a
combination of dry bulb temperature, wet bulb
temperature and ventilation.
4.4.2.3.2 Maintain temperature
a. The atmosphere dry bulb temperature in the habitable volume shall be
selectable within the operational range.
b. The accuracy for the stabilized dry bulb temperature in the habitable
volume shall be specified.
c. Removal of excess sensible heat from the atmosphere or addition of
sensible heat into the atmosphere shall be provided at a rate capable of
maintaining the atmosphere temperature within the specified range.
d. The points of measurement for the dry bulb temperature shall be
representative for the habitable volume situation.
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4.4.2.3.3 Maintain atmosphere humidity
a. The range for the atmosphere relative humidity in the habitable volume
shall be specified.
b. The range for the atmosphere dew point in the pressurized volume shall
be specified.
NOTE Relative humidity is in relation to human comfort
evaluation; dew point limits are intended to
prevent condensation. Both measurements indicate
the water vapour content of the atmosphere.
4.4.2.3.4 Monitor atmosphere humidity
a. The range and the accuracy to monitor the atmosphere relative humidity
in the habitable volumes shall be specified.
b. The range and accuracy of the atmosphere dew point temperature to be
monitored in the pressurized volumes shall be specified.
c. Water vapour shall be removed from or added to the pressurized volume
atmosphere at a rate capable of maintaining the specified range.
4.4.2.3.5 Circulate atmosphere
a. Ventilate habitable volume: atmosphere velocities in the habitable
volume shall be maintained within the specified air velocity ranges,
adapted to total atmospheric pressure situation.
b. Gas velocity ranges can differ between habitable and non-habitable
volume.
c. Exchange of atmosphere between pressurized volumes: atmosphere
exchange between connected pressurized volumes shall be specified.
d. Monitor ventilation and atmosphere exchange: Location of ventilation
and atmosphere exchange monitoring shall be specified.
NOTE Since atmosphere circulation in the habitable
...

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