ISO 9875:2023

FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 9875
ISO/TC 8/SC 6
Ships and marine technology —
Secretariat: JISC
Marine echo-sounding equipment
Voting begins on:
2023-02-07
Navires et technologie maritime — Appareils de sondage par écho
Voting terminates on:
2023-04-04
RECIPIENTS OF THIS DRAFT ARE INVITED TO
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 9875:2023(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS. © ISO 2023

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ISO/FDIS 9875:2023(E)
FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 9875
ISO/TC 8/SC 6
Ships and marine technology —
Secretariat: JISC
Marine echo-sounding equipment
Voting begins on:
Navires et technologie maritime — Appareils de sondage par écho
Voting terminates on:
COPYRIGHT PROTECTED DOCUMENT
© ISO 2023
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
RECIPIENTS OF THIS DRAFT ARE INVITED TO
ISO copyright office
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
CP 401 • Ch. de Blandonnet 8
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
CH-1214 Vernier, Geneva
DOCUMENTATION.
Phone: +41 22 749 01 11
IN ADDITION TO THEIR EVALUATION AS
Reference number
Email: copyright@iso.org
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO­
ISO/FDIS 9875:2023(E)
Website: www.iso.org
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
Published in Switzerland
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN­
DARDS TO WHICH REFERENCE MAY BE MADE IN
ii
  © ISO 2023 – All rights reserved
NATIONAL REGULATIONS. © ISO 2023

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ISO/FDIS 9875:2023(E)
Contents Page
Foreword .v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Abbreviated terms . 3
5 Performance requirements . .4
5.1 General . 4
5.2 Functionality . 4
5.2.1 Range performance . . . 4
5.2.2 Range scales . 4
5.2.3 Main display . 4
5.2.4 Other displays . 4
5.2.5 Pulse repetition rate . 4
5.2.6 Roll and pitch . 5
5.3 Multiple installation . 5
5.4 Data storage . 5
5.5 Accuracy . 5
5.5.1 Accuracy of measurement. 5
5.5.2 Discrimination . . . 5
5.6 Malfunctions and alert and indications . 5
5.6.1 General . 5
5.6.2 Depth alarm . 6
5.6.3 Failure or reduction in power supply ("power fail" alert) . 6
5.6.4 System failure . 6
5.7 Ergonomic criteria . 7
5.7.1 Operational controls . 7
5.7.2 Presentation of information . 7
5.8 Design and installation . 7
5.9 Interfacing . 7
6 Methods of testing and required test results . 7
6.1 General . 7
6.2 General conditions of measurement . 8
6.3 General underwater test conditions . 8
6.4 Functionality . 8
6.4.1 Range performance . . . 8
6.4.2 Receiver sensitivity . . . 11
6.4.3 Performance checks .12
6.4.4 Range scales . 13
6.4.5 Main display . 13
6.4.6 Other display . .13
6.4.7 Pulse repetition rate .13
6.4.8 Roll and pitch . . .13
6.5 Multiple installation .13
6.6 Data storage . 13
6.6.1 Method of test . 13
6.6.2 Required result . 13
6.7 Accuracy . . 14
6.7.1 Method of test . 14
6.7.2 Required result . 14
6.7.3 Discrimination . . 14
6.8 Malfunctions, alert and indications . 14
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ISO/FDIS 9875:2023(E)
6.8.1 General . 14
6.8.2 Depth alarm . 14
6.8.3 Failure or reduction in power supply . 16
6.8.4 System failure . 16
6.9 Ergonomic criteria . 16
6.9.1 Operational controls . 16
6.9.2 Presentation of information . 17
6.10 Design and installation (test of environment and interference) . 17
6.11 Interfacing . 17
Annex A (informative) Sound absorption coefficient .18
Annex B (normative) Alerts definition for echo-sounding equipment .24
Annex C (normative) IEC 61162 interfaces .25
Bibliography .27
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ISO/FDIS 9875:2023(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 non­governmental, 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.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 8, Ships and marine technology,
Subcommittee SC 6, Navigation and ship operations.
This fourth edition cancels and replaces the third edition (ISO 9875:2000), which has been technically
revised. It also incorporates the Technical Corrigendum ISO 9875:2000/Cor 1:2006.
The main changes are as follows:
— the normative references have been updated;
— bridge alert management requirements have been added in 5.6 and the test method in 6.8;
— interface requirements have been added in 5.9;
— Annex B has been replaced with a new Annex on alerts definition, including alert identifiers
— added new Annex C on IEC 61162 interfaces overview.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
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ISO/FDIS 9875:2023(E)
Introduction
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 document is aligned with IMO Resolutions, in particular IMO Resolution A.694(17), IMO Resolution
A.224(VII), IMO Resolution MSC.74(69) and IMO Resolution MSC.302(87).
Any text in this document which is a citation from the IMO Resolution MSC.74(69), Annex 4, appears in
italics. Within these citations, any changes to the original wording of the IMO Resolution MSC.74(69),
Annex 4, are written in upright font.
In this document, the following verbal forms are used:
— “shall” indicates a requirement;
— “should” indicates a recommendation;
— “may” indicates a permission;
— “can” indicates a possibility or a capability.
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FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 9875:2023(E)
Ships and marine technology — Marine echo-sounding
equipment
1 Scope
This document 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) as amended by IMO Resolution MSC.74(69),
Annex 4.
This document is intended to be used in conjunction with IMO Resolution A.694(17) and with IEC 60945.
For bridge alert management, IMO Resolution MSC.302(87) supersedes IMO Resolution MSC.74(69),
Annex 4. Accordingly, this document incorporates references to IEC 62923-1 and IEC 62923-2 which are
associated with Resolution MSC.302(87) for requirements and tests where applicable.
In accordance with IMO Resolution MSC.74(69), Annex 4, Articles 1 and 2, 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 document is applicable for ship speeds from 0 kn to 30 kn.
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.
IEC 60945, Maritime navigation and radiocommunication equipment and systems — General requirements
— Methods of testing and required test results
IEC 61162­1, Maritime navigation and radiocommunication equipment and systems — Digital interfaces —
Part 1: Single talker and multiple listeners
IEC 61162­2, Maritime navigation and radiocommunication equipment and systems — Digital interfaces —
Part 2: Single talker and multiple listeners, high-speed transmission
IEC 61162­450, Maritime navigation and radiocommunication equipment and systems — Digital interfaces
— Part 450: Multiple talkers and multiple listeners — Ethernet interconnection
IEC 62288, Maritime navigation and radiocommunication equipment and systems — Presentation of
navigation-related information on shipborne navigational displays — General requirements, methods of
testing and required test results
IEC 62923­1:2018, Maritime navigation and radiocommunication equipment and systems — Bridge alert
management — Part 1: Operational and performance requirements, methods of testing and required test
results
IEC 62923­2, Maritime navigation and radiocommunication equipment and systems — Bridge alert
management — Part 2: Alert and cluster identifiers and other additional features
IMO Resolution MSC 74(69), Adoption of New and Amended Performance Standards, Annex 4, Amendments
to Resolution A.224(VII) — Performance standard for echo sounding equipment, May 1998
IMO Resolution MSC 302(87), Adoption of Performance standards for bridge alert management, May 2010
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
1
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ISO/FDIS 9875:2023(E)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
source level
S
maximum root mean square sound pressure level at a point on the principal axis of the transducer (3.5),
as measured in the far field but referred to the distance of 1 m
Note 1 to entry: 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 (3.5), when
used as a transmitter, to that of an omnidirectional transducer, with the same total radiated acoustic
power
Note 1 to entry: 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 = 10 lg( f − f )
1 2
where f and f are respectively the upper and lower frequencies, expressed in hertz.
1 2
Note 1 to entry: 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
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
3.6
performance check
short test to confirm compliance with the essential requirements specified in the equipment standards
Note 1 to entry: In this document, a performance check is a non-quantitative visual check confirming that the
system is still operative for the purpose of IEC 60945.
3.7
inspection
visual check of the equipment or documentation
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ISO/FDIS 9875:2023(E)
3.8
pre-conditioning
treatment of a specimen with the objective of removing or partly counteracting the effects of its
previous history
3.9
bridge alert management
BAM
overall concept for management, handling and harmonized presentation of alerts on the bridge
3.10
central alert management
CAM
functionality for the management of the presentation of alerts on the central alert management
human machine interface (CAM-HMI) (3.11), the communication of alert states between CAM­HMI and
navigational systems and sensors
[SOURCE: IMO Resolution MSC.302(87), Appendix 1]
Note 1 to entry: The functions can be centralized or partly centralized in subsystems and interconnected via a
standardized alert­related communication.
3.11
central alert management human machine interface
CAM-HMI
human machine interface for centralized presentation and handling of alerts on the bridge
[SOURCE: IMO Resolution MSC.302(87), Appendix 1]
3.12
central alert management system
CAM system
combined functionality of central alert management (3.10) and central alert management human machine
interface (3.11)
[SOURCE: IEC 62923-1:2018, 3.1.18]
4 Abbreviated terms
DPT depth
ECDIS electronic chart display and information system
ES echo-sounding equipment
EUT equipment under test
BAM bridge alert management
CAM central alert management
CAM­HMI central alert management human machine interface
VDR voyage data recorder
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ISO/FDIS 9875:2023(E)
5 Performance requirements
5.1 General
Echo-sounding equipment shall comply with IMO Resolution MSC.74(69), Annex 4 and with the general
requirements of IEC 60945, where applicable.
Echo-sounding equipment shall comply with IEC 62288.
5.2 Functionality
5.2.1 Range performance
In accordance with IMO Resolution MSC.74(69), Annex 4, Article 5.1.1, 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
In accordance with IMO Resolution MSC.74(69), Annex 4, Article 5.1.2, 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.
Where an automatic range is provided, a device to select these ranges manually shall be available to
override the automatic range.
Where phased ranges, not starting from zero, are available, an indication shall be provided to show that
such a range is in use.
Positive indication of the range in use shall be provided in all cases.
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 a draught value.
5.2.3 Main display
In accordance with IMO Resolution MSC.74(69), Annex 4, Article 5.1.3, the primary presentation shall be
a suitable graphical display which provides the immediate depth and a visible record of soundings.
The displayed record shall show at least 15 min of soundings on the deep range scale.
Multi-colour display may be used. In this case, the colour assignment shall be clearly explained in the
manual.
5.2.4 Other displays
In accordance with IMO Resolution MSC.74(69), Annex 4, Article 5.1.4, 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
In accordance with IMO Resolution MSC.74(69), Annex 4, Article 5.1.5, 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.
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ISO/FDIS 9875:2023(E)
5.2.6 Roll and pitch
In accordance with IMO Resolution MSC.74(69), Annex 4, Article 5.1.6, the performance of the equipment
shall be such that it will meet the requirements of this document when the ship is rolling ±10° and/or
pitching ±5°.
5.3 Multiple installation
In accordance with IMO Resolution MSC.74(69), Annex 4, Article 5.1.7, more than one transducer and
associated transmitter-receiver may be fitted.
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
In accordance with IMO Resolution MSC.74(69), Annex 4, Article 5.1.8, it shall be possible to record on
paper recording or other means the information about:
— the depth(s), and
— the associated time for 12 h.
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
In accordance with IMO Resolution MSC.74(69), Annex 4, Article 5.2.1, 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 ±5 m 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
In accordance with IMO Resolution MSC.74(69), Annex 4, Article 5.2.2, 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.
5.6 Malfunctions and alert and indications
5.6.1 General
The general presentation, handling and communication for alerts shall comply with the requirements
stated in IMO Resolution MSC.302(87); IEC
...

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ISO TC 8/SC 6
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Secretariat: JISC
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Ships and marine technology — Marine echo-sounding equipment
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Navires et technologie maritime — Appareils de sondage par écho
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ISO/FDIS 9875:202#(E)
© ISO 202# 2023
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All rights reserved. Unless otherwise specified, or required in the context of its implementation, no
part of this publication may be reproduced or utilized otherwise in any form or by any means,
electronic or mechanical, including photocopying, or posting on the internet or an intranet, without
prior written permission. Permission can be requested from either ISO at the address below or
ISO’sISO's member body in the country of the requester.
ISO copyright officeCopyright Office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: + 41 22 749 01 11
Email: copyright@iso.org
Email: copyright@iso.org
Website: www.iso.orgwww.iso.org
Published in Switzerland.
ii © ISO 202# – All rights reserved

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ISO/FDIS 9875:202#(E)
Contents

Foreword . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Abbreviated terms . 4
5 Performance requirements . 4
5.1 General . 4
5.2 Functionality . 5
5.2.1 Range performance . 5
5.2.2 Range scales . 5
5.2.3 Main display . 5
5.2.4 Other displays . 5
5.2.5 Pulse repetition rate . 5
5.2.6 Roll and pitch . 5
5.3 Multiple installation . 6
5.4 Data storage . 6
5.5 Accuracy . 6
5.5.1 Accuracy of measurement . 6
5.5.2 Discrimination . 6
5.6 Malfunctions and alert and indications . 6
5.6.1 General . 6
5.6.2 Depth alarm . 7
5.6.3 Failure or reduction in power supply (‘power fail’ alert) . 7
5.6.4 System failure . 7
5.7 Ergonomic criteria . 8
5.7.1 Operational controls . 8
5.7.2 Presentation of information . 8
5.8 Design and installation . 8
5.9 Interfacing . 8
6 Methods of testing and required test results . 9
6.1 General . 9
6.2 General conditions of measurement . 9
6.3 General underwater test conditions . 9
6.4 Functionality . 10
6.4.1 Range performance (see 5.2.1) . 10
6.4.2 Receiver sensitivity . 13
6.4.3 Performance checks . 13
6.4.4 Range scales (see 5.2.2) . 14
6.4.5 Main display . 14
6.4.6 Other display . 15
6.4.7 Pulse repetition rate (see 5.2.5) . 15
6.4.8 Roll and pitch (see 5.2.6) . 15
6.5 Multiple installation . 15
6.6 Data storage (see 5.4) . 15
6.6.1 Method of test . 15
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ISO/FDIS 9875:202#(E)
6.6.2 Required result . 15
6.7 Accuracy (see 5.5) . 16
6.7.1 Method of test . 16
6.7.2 Required result . 16
6.7.3 Discrimination . 16
6.8 Malfunctions, alert and indications(see5.6) . 16
6.8.1 General . 16
6.8.2 Depth alarm . 17
6.8.3 Failure or reduction in power supply . 19
6.8.4 System failure . 20
6.9 Ergonomic criteria (see 5.7) . 20
6.9.1 Operational controls . 20
6.9.2 Presentation of information. 20
6.10 Design and installation (test of environment and interference) (see 5.8) . 21
6.11 Interfacing (see 5.9 and Annex C) . 21
Annex A (informative) Sound absorption coefficient . 22
Annex B (normative) Alerts definition for echo-sounding equipment . 33
Annex C (normative) IEC 61162 interfaces . 34
Bibliography . 37
Foreword . v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Abbreviated terms . 4
5 Performance requirements . 4
5.1 General . 4
5.2 Functionality . 5
5.2.1 Range performance . 5
5.2.2 Range scales . 5
5.2.3 Main display . 5
5.2.4 Other displays . 5
5.2.5 Pulse repetition rate . 5
5.2.6 Roll and pitch . 5
5.3 Multiple installation . 6
5.4 Data storage . 6
5.5 Accuracy . 6
5.5.1 Accuracy of measurement . 6
5.5.2 Discrimination . 6
5.6 Malfunctions and alert and indications . 6
5.6.1 General . 6
5.6.2 Depth alarm . 7
5.6.3 Failure or reduction in power supply ("power fail" alert) . 7
5.6.4 System failure . 7
5.7 Ergonomic criteria . 8
5.7.1 Operational controls . 8
5.7.2 Presentation of information. 8
5.8 Design and installation . 8
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ISO/FDIS 9875:202#(E)
5.9 Interfacing . 8
6 Methods of testing and required test results . 9
6.1 General . 9
6.2 General conditions of measurement . 9
6.3 General underwater test conditions . 9
6.4 Functionality . 10
6.4.1 Range performance . 10
6.4.2 Receiver sensitivity . 13
6.4.3 Performance checks . 13
6.4.4 Range scales . 14
6.4.5 Main display . 14
6.4.6 Other display . 15
6.4.7 Pulse repetition rate . 15
6.4.8 Roll and pitch . 15
6.5 Multiple installation . 15
6.6 Data storage . 15
6.6.1 Method of test . 15
6.6.2 Required result . 15
6.7 Accuracy . 16
6.7.1 Method of test . 16
6.7.2 Required result . 16
6.7.3 Discrimination . 16
6.8 Malfunctions, alert and indications . 16
6.8.1 General . 16
6.8.2 Depth alarm . 17
Figure 1 — Example of EUT and test configuration . 19
6.8.3 Failure or reduction in power supply . 19
6.8.4 System failure . 20
6.9 Ergonomic criteria . 20
6.9.1 Operational controls . 20
6.9.2 Presentation of information . 20
6.10 Design and installation (test of environment and interference) . 21
6.11 Interfacing . 21
Annex A (informative) Sound absorption coefficient . 22
Table A.1 — Temperature and salinity values versus depth for the seven areas . 25
Table A.2 — Values of sound absorption coefficient . 27
Figure A.1 — Operating frequency vs figure of merit . 32
Annex B (normative) Alerts definition for echo-sounding equipment . 33
Table B.1 — Classification of echo-sounding equipment alerts . 33
Annex C (normative) IEC 61162 interfaces . 34
Figure C.1 — Echo-sounding equipment logical interface . 34
Table C.1 — Sentences from IEC 61162-1 transmitted by the echo-sounding equipment . 34
Table C.2 — Sentences from IEC 61162-1 received by the echo-sounding equipment . 36
Bibliography . 37
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ISO/FDIS 9875:202#(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.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives 2 (see
www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any
patent rights identified during the development of the document will be in the Introduction and/or on
the ISO list of patent declarations received (see www.iso.org/patentswww.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the World
Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.htmlwww.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 8, Ships and marine technology,
Subcommittee SC 6, Navigation and ship operations.
This fourth edition cancels and replaces the third edition (ISO 9875:2000 and ISO 9875:2000/Cor
1:2006), which has been technically revised. It also incorporates the Technical Corrigendum
ISO 9875:2000/Cor 1:2006.
The main changes compared to the previous edition are as follows:
— in Clause 2, replaced IEC 61162 with IEC 61162-1, IEC 61162-2 and IEC 61162-450;, and added
IEC 62288, IEC 62923-1, IEC 62923-2 and IMO Resolution MSC.302(87);
— in 5.6 and the test method in 6.8, added — the normative references have been updated;
— bridge alert management requirements have been added in 5.6 and the test method in 6.8;
— in 5.9, added interface requirements have been added in 5.9;
— former Annex B has been replaced with a new Annex B on alerts definition, including alert identifiers
— added new Annex C on IEC 61162 interfaces overview.
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Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at
www.iso.org/members.htmlwww.iso.org/members.html.
vi © ISO 202# – All rights reserved

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ISO/FDIS 9875:2023 (E)

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ISO/FDIS 9875:2023 (E)
Introduction
The purpose of echo-sounding equipment is to provide reliable information on the depth of water under
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a ship to aid navigation in particular in shallow water.
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This document is aligned with IMO Resolutions, in particular IMO Resolution A.694(17), IMO Resolution
A.224(VII), IMO Resolution MSC.74(69) and IMO Resolution MSC.302(87).
Any text in this document which is a citation from the IMO Resolution MSC.74(69), Annex 4, appears in
italics. Within these citations, any changes to the original wording of the IMO Resolution MSC.74(69),
Annex 4, are written in upright font.
In this document, the following verbal forms are used:
— “shall” indicates a requirement;
— “should” indicates a recommendation;
— “may” indicates a permission;
— “can” indicates a possibility or a capability.
viii © ISO 2023– All rights reserved

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FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 9875:202#(2023(E)
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Ships and marine technology — Marine echo-sounding equipment
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1 Scope
This document 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) as amended by IMO Resolution MSC.74(69), Annex 4.
In addition, it takes account of This document is intended to be used in conjunction with IMO Resolution
A.694(17) and is associated with IEC 60945.
When a requirement in this document differs from IEC 60945, the requirement in this document takes
precedence.
For bridge alert management, IMO Resolution MSC.302(87) supersedes IMO Resolution MSC.74(69),
Annex 4. Accordingly, this document incorporates references to IEC 62923-1 and IEC 62923-2 which are
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associated with Resolution MSC.302(87) for requirements and tests where applicable.
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[In accordance with IMO Resolution MSC.74(69), Annex 4, Articles 1]The purpose of echo-sounding
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equipment is to provide reliable information on the depth of water under a ship to aid navigation in
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particular in shallow water.
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[IMO Resolution MSC.74(69), Annex 4, and 2], 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. Formatted: std_docPartNumber
This document is applicable for ship speeds from 0 kn to 30 kn.
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Any text in this document with wording identical to that in IMO Resolution MSC.74(69), Annex 4 is
printed in italics and the resolution and paragraph numbers and indicated in brackets. Formatted: Font: Not Italic
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32 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.
IEC 60945:2002, Maritime navigation and radiocommunication equipment and systems — General
...