Ships and marine technology - Marine echo-sounding equipment (ISO 9875:2000)

Schiffe und Meerestechnik - Echolote für die Schifffahrt (ISO 9875:2000)

Diese Internationale Norm legt die Mindestanforderungen an Leistung und Beschaffenheit von Echolotanlagen für die Seeschifffahrt sowie Prüfverfahren und Prüfergebnisse entsprechend der IMO-Entschließung A.224(VII) fest. Weiterhin berücksichtigt sie die IMO-Entschließung A.694(17) in Verbindung mit IEC 60945.
Wenn eine Anforderung in dieser Internationalen Norm von IEC 60945 abweicht, dann hat die Anforderung in dieser Internationalen Norm Vorrang.
Die Aufgabe einer Echolotanlage ist es, zur Unterstützung der Navigation zuverlässige Informationen über die Wassertiefe unter einem Schiff, insbesondere in flachem Wasser, zu  liefern.
Diese Internationale Norm ist für Schiffsgeschwindigkeiten von 0 kn bis 30 kn anwendbar.
In dieser Internationalen Norm ist jeder Text, dessen Wortlaut mit der IMO-Entschließung A.224(VII) oder IMO-Entschließung A.694(17) übereinstimmt, kursiv gedruckt.
ANMERKUNG   IMO-Entschließung A.224(VII) bedeutet: IMO-Entschließung A.224(VII), mit Änderungen nach IMO-Entschließung MSC.74(69), Anhang 4.

Navires et technologie maritime - Appareils de sondage par écho (ISO 9875:2000)

L'ISO 9875:2000 spécifie les exigences minimales de fonctionnement et de performances, les méthodes d'essai et les résultats d'essais des appareils marins de sondage par écho, exigés pour se conformer aux standards de performance adoptés par la Résolution A.224(VII) de l'OMI. De plus, elle tient compte de la Résolution A.694(17) de l'OMI, et elle est associée à l'IEC 60945.
Lorsqu'une exigence de la présente Norme internationale diffère de l'IEC 60945, c'est l'exigence de la présente Norme internationale qui a priorité.
L'objectif des appareils de sondage par écho est de fournir des informations fiables relatives à la profondeur d'eau en dessous d'un navire pour faciliter la navigation, en particulier dans des eaux peu profondes.
L'ISO 9875:2000 s'applique à des vitesses de navires allant de 0 kn à 30 kn.
L'ensemble du texte de la présente Norme internationale utilisant une terminologie identique à celle de la Résolution A.224(VII) de l'OMI et de la Résolution A.694(17) de l'OMI est imprimé en italique.
NOTE          La Résolution A.224(VII) correspond à la Résolution A.224(VII) amendée par l'Annexe 4 de la Résolution MSC.74(69).

Ladje in pomorska tehnologija – Globinomer/Oprema za merjenje globine (ISO 9875:2000)

General Information

Status
Published
Publication Date
31-Aug-2004
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
01-Sep-2004
Due Date
01-Sep-2004
Completion Date
01-Sep-2004

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SLOVENSKI STANDARD
SIST EN ISO 9875:2004
01-september-2004
Ladje in pomorska tehnologija – Globinomer/Oprema za merjenje globine (ISO
9875:2000)
Ships and marine technology - Marine echo-sounding equipment (ISO 9875:2000)
Schiffe und Meerestechnik - Echolote für die Schifffahrt (ISO 9875:2000)
Navires et technologie maritime - Appareils de sondage par écho (ISO 9875:2000)
Ta slovenski standard je istoveten z: EN ISO 9875:2001
ICS:
47.020.70 Navigacijska in krmilna Navigation and control
oprema equipment
SIST EN ISO 9875:2004 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 9875:2004

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SIST EN ISO 9875:2004
EUROPEAN STANDARD
EN ISO 9875
NORME EUROPÉENNE
EUROPÄISCHE NORM
December 2001
ICS 47.020.70 Supersedes EN ISO 9875:1997
English version
Ships and marine technology - Marine echo-sounding
equipment (ISO 9875:2000)
Navires et technologie maritime - Appareils de sondage par Schiffe und Meerestechnik - Echolote für die Schifffahrt
écho (ISO 9875:2000) (ISO 9875:2000)
This European Standard was approved by CEN on 12 November 2001.
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 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 Management Centre has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,
Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2001 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 9875:2001 E
worldwide for CEN national Members.

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SIST EN ISO 9875:2004
EN ISO 9875:2001 (E)
CORRECTED  2002-02-06
Foreword
The text of the International Standard from Technical Committee ISO/TC 8 "Ships and marine
technology" of the International Organization for Standardization (ISO) has been taken over as a
European Standard by Technical Committee CEN/TC 300 "Sea-going vessels and marine
technology", the secretariat of which is held by DIN.
This document supersedes EN ISO 9875:1997.
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 June 2002, and conflicting national
standards shall be withdrawn at the latest by June 2002.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of
the following countries are bound to implement this European Standard: Austria, Belgium, Czech
Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg,
Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom.
Endorsement notice
The text of the International Standard ISO 9875:2000 has been approved by CEN as a
European Standard without any modifications.
2

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SIST EN ISO 9875:2004
INTERNATIONAL ISO
STANDARD 9875
Third edition
2000-11-01
Ships and marine technology — Marine
echo-sounding equipment
Navires et technologie maritime — Appareils de sondage par écho
Reference number
ISO 9875:2000(E)
©
ISO 2000

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SIST EN ISO 9875:2004
ISO 9875:2000(E)
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ii © ISO 2000 – All rights reserved

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SIST EN ISO 9875:2004
ISO 9875:2000(E)
Contents Page
Foreword.iv
1 Scope .1
2 Normative references .1
3 Terms and definitions .1
4 Abbreviated terms .3
5 Performance requirements.3
5.1 General.3
5.2 Functionality.3
5.3 Multiple installation .4
5.4 Data storage .4
5.5 Accuracy.4
5.6 Malfunctions, alarms and indications.5
5.7 Ergonomic criteria .5
5.8 Design and installation .5
5.9 Interfacing.5
5.10 Safety precautions.6
5.11 Marking .6
5.12 Information .6
6 Methods of testing and required test results.6
6.1 General.6
6.2 General conditions of measurement .6
6.3 General underwater test conditions .6
6.4 Functionality.7
6.5 Multiple installation .11
6.6 Data storage .12
6.7 Accuracy.12
6.8 Malfunctions, alarm and indications.12
6.9 Ergonomic criteria .13
6.10 Other tests.13
6.11 Interfacing.13
6.12 Safety precautions.13
6.13 Marking .13
6.14 Information .13
Annex A (normative) Sound absorption coefficient.14
Annex B (informative) Equivalent requirements in ISO 9875 and IMO Resolutions .20
Bibliography.21
© ISO 2000 – All rights reserved iii

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SIST EN ISO 9875:2004
ISO 9875:2000(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO
member bodies). The work of preparing International Standards is normally carried out through ISO technical
committees. Each member body interested in a subject for which a technical committee has been established has
the right to be represented on that committee. International organizations, governmental and non-governmental, in
liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical
Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.
Draft International Standards adopted by the technical committees are circulated to the member bodies for voting.
Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this International Standard may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights.
International Standard ISO 9875 was prepared by Technical Committee ISO/TC 8, Ships and marine technology,
Subcommittee SC 6, Navigation.
This third edition cancels and replaces the second edition (ISO 9875:1996), which has been technically revised.
Annex A forms a normative part of ISO 9875. Annex B is for information only.
iv © ISO 2000 – All rights reserved

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SIST EN ISO 9875:2004
INTERNATIONAL STANDARD ISO 9875:2000(E)
Ships and marine technology — Marine echo-sounding equipment
1 Scope
This International Standard specifies the minimum operational and performance requirements, methods of testing
and test results of marine echo-sounding equipment required to comply with the performance standards adopted by
the IMO Resolution A.224(VII). In addition, it takes account of IMO Resolution A.694(17) and is associated with
IEC 60945.
When a requirement in this International Standard is different from IEC 60945, the requirement in this International
Standard takes precedence.
The purpose of echo-sounding equipment is to provide reliable information on the depth of water under a ship to
aid navigation in particular in shallow water.
This International Standard is applicable for ship speeds from 0 kn to 30 kn.
Any text in this International Standard with wording identical to that in the IMO Resolution A.224(VII) and IMO Res.
A.694(17) is printed in italics.
NOTE Resolution A.224(VII) represents Resolution A.224(VII) as amended by Resolution MSC.74(69), annex 4.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of
this International Standard. For dated references, subsequent amendments to, or revisions of, any of these
publications do not apply. However, parties to agreements based on this International Standard are encouraged to
investigate the possibility of applying the most recent editions of the normative documents indicated below. For
undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC
maintain registers of currently valid International Standards.
IEC 60945:1996, Maritime navigation and radiocommunication equipment and systems — General requirements,
methods of testing and required test results.
IEC 61162, Maritime navigation and radiocommunication equipment and systems — Digital interfaces.
IMO Resolution A.224(VII), Performance standards for echo-sounding equipment.
IMO Resolution A.694(17), General requirements for shipborne radio equipment forming part of the global maritime
distress and safety system (GMDSS) and for electronic navigational aids.
International Convention of Safety of Life at Sea (SOLAS) Chapter V, Regulation 12, Shipborne navigational
equipment.
3 Terms and definitions
For the purposes of this International Standard, the following terms and definitions apply.
© ISO 2000 – All rights reserved 1

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SIST EN ISO 9875:2004
ISO 9875:2000(E)
3.1
source level
S
maximum root mean square (r.m.s) sound pressure level at a point on the principal axis of the transducer, as
measured in the far field but referred to the distance of 1 m
NOTE This value is expressed in decibels.
3.2
receiving directivity index
D
ratio of the acoustic power density at a distant point on the principal axis of the transducer, when used as a
transmitter, to that of an omnidirectional transducer, with the same total radiated acoustic power
NOTE This value is expressed in decibels.
3.3
receiving bandwidth
B
bandwidth at which the response of the overall system, measured through water, is 3 dB below the maximum
response of the system
B =10lg(f � f )
1 2
where f and f are respectively the upper and lower frequencies expressed in hertz
1 2
NOTE This value is expressed in decibels.
3.4
minimum detectable signal-to-noise ratio
E
ratio of the signal level, expressed in decibels, to the background noise level, expressed in decibels, in the
bandwidth of the receiver required to give a minimum detectable signal on the display
3.5
speed of sound in water
1 500 m/s in the context of this International Standard
3.6
transducer
substance or device, such as a piezoelectric element, that converts an input electrical energy into an acoustic
energy and vice versa, installed on the ship’s hull and exposed to the sea water
3.7
performance test
test to confirm full compliance with the requirements of the equipment standard
3.8
performance check
short test to confirm compliance with the essential requirements specified in the equipment standards
NOTE In this International Standard, a performance check means non-quantitative visual check that the system is still
operative for the purpose of IEC 60945.
3.9
inspection
visual check of the equipment or documentation
2 © ISO 2000 – All rights reserved

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SIST EN ISO 9875:2004
ISO 9875:2000(E)
3.10
pre-conditioning
treatment of a specimen with the objective of removing or partly counteracting the effects of its previous history
4 Abbreviated terms
For the purposes of this International Standard, the following abbreviated terms apply.
DPT depth
ECDIS electronic chart display and information system
EMC electromagnetic compatibility
EUT equipment under test
VDR voyage data recorder
5 Performance requirements
5.1 General
Echo-sounding equipment shall comply with the following performance requirements and with the general
requirements of IEC 60945, where applicable.
5.2 Functionality
5.2.1 Range performance
Under normal propagation and sea bed reflectibility conditions, the equipment shall be capable of measuring any
clearance under the transducer between 2 m and 200 m.
5.2.2 Range scales
5.2.2.1 The equipment shall provide a minimum of two range scales one of which, the shallow range, shall
cover a range of 20 m, and the other, the deep range, shall cover a range of 200 m.
5.2.2.2 Where an automatic range is provided, a device to select these ranges manually shall be available to
override the automatic range.
5.2.2.3 Where phased ranges, not starting from zero, are available, an indication shall be provided to show
that such a range is in use.
5.2.2.4 Positive indication of the range in use shall be provided in all cases.
5.2.2.5 Where depth measurement relative to the sea surface is provided, in addition to measurement of the
depth of water under the ship, there shall be a positive indication of an offset (draught) value.
5.2.3 Main display
5.2.3.1 The primary presentation shall be a suitable graphical display which provides the immediate depth and
a visible record of soundings.
5.2.3.2 The displayed record shall show at least 15 minutes of soundings on the deep range scale.
© ISO 2000 – All rights reserved 3

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SIST EN ISO 9875:2004
ISO 9875:2000(E)
5.2.3.3 Multi-colour display may be used. In this case, the colour assignment shall be clearly explained in the
manual.
5.2.4 Other displays
Other forms of display may be added, but these shall not affect the normal operation of the main display.
5.2.5 Pulse repetition rate
The pulse repetition rate shall not be slower than 12 pulses per minute on the deep range and 36 pulses per
minute on the shallow range.
5.2.6 Roll and pitch
The performance of the equipment shall be such that it will meet the requirements of this International Standard
when the ship is rolling � 10° and/or pitching� 5°.
5.3 Multiple installation
5.3.1 More than one transducer and associated transmitter-receiver may be fitted.
5.3.2 If more than one transducer is used:
� means shall be available to display the depths from the different transducers separately; and
� a clear indication of the transducer(s) in use shall be provided.
5.4 Data storage
It shall be possible to record on paper recording or other means the information about:
� the depth(s), and
� the associated time for 12 hours.
There shall be means to retrieve the recorded information. The information may be recorded and retrieved in the
form of graphics or digital readouts at intervals of 1 min.
5.5 Accuracy
5.5.1 Accuracy of measurement
Based on a sound speed in water of 1 500 m/s, the tolerance of the indicated depth shall be either:
� � 0,5 m on the shallow range scale, respectively � 5m on the deep range scale; or
� � 2,5 % of the indicated depth,
whichever is the greater.
NOTE These tolerances take no account of the ship’s roll and pitch.
5.5.2 Discrimination
The scale of display shall not be smaller than 5,0 mm per metre depth on the shallow range scale and 0,5 mm per
metre depth on the deep range scale.
4 © ISO 2000 – All rights reserved

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SIST EN ISO 9875:2004
ISO 9875:2000(E)
5.6 Malfunctions, alarms and indications
5.6.1 Depth alarm
An alarm signal — both visual and audible with mute function — shall be provided when the water depth is below a
pre-set value. If the pre-set alarm depth is not referenced to the transducer position, there shall be an indication of
the reference position.
5.6.2 Failure or reduction in power supply
Alarm signals, both visual and audible (with mute function) to the navigator on the watch, shall be provided to
indicate failure or a reduction in the power supply to the echo sounder which would affect the safe operation of the
equipment. This facility may be integrated into a switchboard or elsewhere; it need not necessarily be an integral
part of the equipment.
5.7 Ergonomic criteria
5.7.1 Operational controls
The function of range scale selection shall be directly accessible. Other functions shall be directly accessible and
immediately effected by dedicated controls or primary access in an associated menu.
The settings for the following functions shall be recognizable in all light conditions:
� range scale; and
� preset depth alarm.
5.7.2 Presentation of information
5.7.2.1 Marks
The graphical display shall be capable of showing:
� depth marks at intervals not larger than one-tenth of the range/scale in use; and
� time marks at intervals not exceeding 5 min.
5.7.2.2 Paper recording
If paper is used for recording either by marks on the recording paper or by other means, there shall be a clear
indication when the paper remaining is less than 1 m.
5.8 Design and installation
The equipment shall comply with IMO resolution A.694(17).
5.9 Interfacing
Output(s) shall be available from which depth information may be supplied to other equipment such as remote
digital displays, voyage data recorder and a track control system.
These outputs shall include depth under keel, the depth scale currently being displayed, the transducer in use in
multiple installations and other status information where available.
© ISO 2000 – All rights reserved 5

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SIST EN ISO 9875:2004
ISO 9875:2000(E)
These outputs shall be digital, serial communication, facilities which shall comply with the relevant International
Standards (IEC 61162).
5.10 Safety precautions
In the case of equipment using a high voltage electrosensitive recording medium and/or a moving writing
mechanism, and where access to the record is possible while the echo-sounding equipment is operating, the
equipment shall provide for operator safety.
5.11 Marking
The equipment shall be provided with an indication of the manufacturer, type and serial number.
Each unit of equipment normally to be installed in the vicinity of a standard compass or a magnetic steering
compass shall be clearly marked with the safe distance at which it may be mounted from such compasses.
5.12 Information
Information shall be provided to enable competent members of a ship’s crew to operate and maintain the
equipment efficiently.
6 Methods of testing and required test results
6.1 General
Any requirement in clause 5 for which no test is specified in this clause or in IEC 60945, shall be checked by
inspection of the equipment, the manufacturer’s drawing or the relevant documents. The results of the inspection
shall be stated in the test report.
6.2 General conditions of measurement
All the general requirements of IEC 60945 shall be carried out before tests to verify whether the Equipment Under
Test (EUT) meets these technical requirements. The equipment shall comply with those requirements of IEC 60945
appropriate to its category, that is “protected” (from the weather), “exposed” (to the weather), or “submerged” (in
continuous contact with sea water).
The manufacturer shall declare which equipment or units are “protected”, “exposed” or “submerged”.The
manufacturer shall declare the “pre-conditioning” required before environmental checks.
Where pre-conditioning is called for, it is the first process in the test procedure. It may be effected by subjecting the
specimen to climatic, electrical, or any other conditions required by the relevant specification in order that the
properties of the specimen may be stabilized before measurements and test.
6.3 General underwater test conditions
The equipment transducer in its housing, complete with acoustic window if provided, shall be attached underwater
to a clamp calibrated in degrees to enable the transducer to be rotated to any required angle about the major axis
of the face of its element (that is about the longer axis, which will run parallel to the ship fore-and-aft line) and about
the minor axis (the athwartships axis) where the element is rectangular or elliptical, or about any facial axis where
the element is circular.
A calibrated hydrophone, which can be replaced by a calibrated projector (or, alternatively, a single instrument
capable of being used in either role as required) shall be mounted under the water at a suitable known distance, d,
from the transducer and directed towards it. Initially, the transducer shall be directed towards the calibrated
hydrophone.
6 © ISO 2000 – All rights reserved

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SIST EN ISO 9875:2004
ISO 9875:2000(E)
NOTE See [5], [6] and [7] in the bibliography for details.
In order to minimize near-field effects, distance d, in metres, shall not be less than
2
1, 25af c
where
a is the largest active dimension of the transducer element, in metres, appropriate to the mode of use, that
is transmission or reception (usually the same figure for either);
f is the highest operation frequency of the echo-sounding equipment, in hertz;
c is the speed of sound in water, equal to 1 500 m/s (see 3.5).
Precautions shall be taken to minimize the effects of reverberation in the water. These precautions shall include the
use of gated pulse measurement techniques. These techniques are essential in the case of some echo-sounding
equipment receivers that operate in a non-linear mode.
6.4 Functionality
6.4.1 Range performance
6.4.1.1 Minimum depth test method
The transducer in its housing, complete with an acoustic window if provided, shall be immersed in water with its
axis of maximum response directed towards a test target such as the bottom or side of the tank holding the water. It
shall be possible to adjust the physical distance between the transducer and the target.
The test shall be conducted such that no other object or discontinuity shall be capable of affecting the result
significantly.
The equipment shall be set to the shallow scale with the longest pulse length available on that scale, and the
physical distance between the transducer and the test target shall be adjusted until the echo from the target is
displayed separately and distinctly. This physical distance shall be measured and noted as the minimum depth
indication.
6.4.1.2 Result required
The minimum depth shall not be greater than 2 m.
6.4.1.3 Maximum required measurable depth detection using the figure of merit system
The equipment shall be tested by the assessment, under laboratory conditions, of the system figure of merit for a
water depth of 200 m.
The figure of merit, L�, expressed in decibels, is defined as
LS��� 2r�D�B�E (1)
and shall exceed L as indicated by the following relationship:
0
LL�� 2�R�K�N�x�y�z (2)
0
© ISO 2000 – All rights reserved 7

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SIST EN ISO 9875:2004
ISO 9875:2000(E)
where
S is the source level, in decibels relative to 1µPa at 1 m;
r is the one-way loss figure due to roll and pitch, in decibels;
D is the receiving directivity index, in decibels;
B is the receiving bandwidth, in decibels relative to 1 Hz;
E is the minimum detectable signal-to-noise ratio, in decibels;
L is the spreading loss due to divergence, equal to 20 lg(2 000R);
R is the depth, in kilometres;
� is the sound absorption coefficient of sea water in decibels per kilometre (see annex A):
combining R and � gives 2�R, as the total water attenuation loss, in decibels;
K is the bottom reflection loss at normal incidence and is taken to be 25 dB;
N is the background noise level, in decibels relative to 1µPa in a 1 Hz bandwidth, equal to 82,5 � (50/3)
lgf, f in kHz ;
x is the transmission loss in the case when the transducer is mounted inside the hull, in decibels;
y is a signal excess of 10 dB above the minimum
...

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