ISO 22013:2021

INTERNATIONAL ISO
STANDARD 22013
First edition
Marine environment sensor
performance — Specifications,
testing and reporting — General
requirements
Navires et technologie maritime — Performances des capteurs marins
PROOF/ÉPREUVE
Reference number
ISO 22013:2020(E)
©
ISO 2020

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ISO 22013:2020(E)

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© ISO 2020
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ISO 22013:2020(E)

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3  Terms and definitions . 1
4  Specifications .14
4.1 General .14
4.2 Calibration .14
4.3 Range .15
4.3.1 Calibrated range .15
4.3.2 Measuring range.15
4.3.3 Maximum range .15
4.4 Accuracy .15
4.5 Resolution .15
4.6 Response time.15
4.7 Depth and pressure .15
4.7.1 Maximum depth rating .15
4.7.2 Crush depth rating . . .15
4.8 Sample rate .15
4.9 Mechanical .15
4.9.1 Wetted materials .15
4.9.2 Exterior dimensions.16
4.9.3 Mass or weight in air .16
4.9.4 Weight in freshwater .16
4.9.5 Weight in seawater . .16
4.9.6 Operating temperature range .16
4.10 Electrical .16
4.10.1 Input voltage range .16
4.10.2 Operating power consumption .17
4.10.3 Startup power consumption .17
4.11 Interface .17
4.11.1 Electrical connections .17
4.11.2 Communications protocol.17
4.12 Stability .17
4.13 Shelf-life .18
5 Test methods .18
5.1 Overview .18
5.2 General experimental design .18
5.2.1 General.18
5.2.2 Sensor settings.18
5.2.3 Reference .18
5.2.4 Re-calibration .18
5.3 Calibration .18
5.3.1 General.18
5.3.2 Calibration method .19
5.3.3 Experimental design — Layout of the calibration .19
5.3.4 Calibration curve .19
5.3.5 Post-calibration operations .20
5.4 Accuracy .20
5.4.1 General.20
5.4.2 Modifications to ISO 5725 .20
5.4.3 Statistical model .21
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ISO 22013:2020(E)

5.4.4 Determination of precision .21
5.4.5 Experimental design — Layout of the precision experiment .22
5.4.6 Reference .23
5.4.7 Determination of trueness (bias) .23
5.4.8 Statistical analysis . .23
5.5 Resolution .23
5.5.1 General.23
5.5.2 Experimental design .24
5.5.3 Calculation of s .24
noise
5.5.4 Calculation of s .24
noise
ij
5.6 Response time.24
5.6.1 General.24
5.6.2 Experimental design .24
5.6.3 Response curve .25
5.7 Depth and pressure .26
5.7.1 Maximum depth rating .26
5.7.2 Crush depth rating . . .27
5.7.3 Pressure case void .27
5.8 Mechanical .27
5.8.1 Wetted materials .27
5.8.2 Weight in freshwater .27
5.8.3 Weight in seawater . .28
5.8.4 Operating temperature range .28
5.9 Electrical .28
5.9.1 Input voltage range .28
5.9.2 Operating power consumption .28
5.9.3 Startup power consumption .29
5.10 Interface .29
5.10.1 General.29
5.10.2 Power on/standby .29
5.10.3 Galvanic isolation test . .29
5.11 Stability .29
5.11.1 General.29
5.11.2 Experimental design .29
5.11.3 Calculation of d .30
5.11.4 Field stability .31
5.12 Shelf-life .31
5.12.1 General.31
5.12.2 Experimental design .31
5.12.3 Calculation of d . 31
6 Publication .31
6.1 General .31
6.2 Data sheets .32
6.2.1 General.32
6.2.2 Test reports.33
6.3 Calibration certificates .33
Annex A (informative) Determination of the accuracy (precision and trueness) — Example .35
Annex B (informative) Determination of the response time — Examples .39
Annex C (informative) Data sheet for a sound velocity sensor — Example .43
Bibliography .44
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ISO 22013:2020(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. 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. 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 13, Marine technology.
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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Introduction
Oceans are intertwined with many of humanity’s priorities, including trade, food, energy, climate
and security. Understanding what’s going on below the sea surface is important for making decisions
around maritime boundaries, exploiting energy and mineral resources, expanding waterways, and
monitoring aquaculture. All depend on the availability of data produced by marine environment sensors
that measure physical, ecological and chemical parameters of seawater, such as salinity, temperature,
oxygen, carbon dioxide and acidity.
As an example of the growing importance of these data, marine business is increasingly mandated
by law to record them to meet environmental regulations. But common definitions for even basic
performance specifications of these sensors, such as accuracy or stability, don't exist. This weakens
the utility of the laws and diminishes confidence in sensor performance. It also acts to dampen the
market forces driving sensor innovation, as it is difficult for end-users to compare and reward true
breakthroughs from existing manufacturers, or to trust new entrants. This document aims to address
this by establishing a set of performance specifications common to all marine environment sensors,
including terms, definitions and test methods.
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INTERNATIONAL STANDARD ISO 22013:2020(E)
Marine environment sensor performance — Specifications,
testing and reporting — General requirements
1 Scope
This document defines terms, specifies test methods and provides reporting requirements for marine
sensor specifications to ensure a consistent reporting by manufacturers.
It is applicable to those devices known as conductivity-temperature-depth (CTDs), sound velocity
probes, multi-parameter sondes and dissolved gas sensors, that measure parameters such as
conductivity, temperature, pressure, sound speed, dissolved oxygen, turbidity, pH, and chlorophyll in
seawater.
It is also generally applicable to all marine environment instruments.
NOTE 1 A ‘CTD’ directly measures conductivity, temperature, and pressure. Depth is derived from pressure
using an equation.
NOTE 2 The term ‘sound velocity probe’ is widely used to describe instruments that measure sound speed. In
this document the term ‘sound velocity’ is used when describing the type of sensor, and the term ‘sound speed’ is
used when describing the parameter or measurand, but these terms can be used interchangeably.
2 Normative references
The following documents are referred to in the text in such a way that some or all 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.
ISO 5725-2:2019, Accuracy (trueness and precision) of measurement methods and results — Part 2: Basic
method for the determination of repeatability and reproducibility of a standard measurement method
ISO/IEC 17025:2017, General requirements for the competence of testing and calibration laboratories
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:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
quantity
parameter
property of a phenomenon, body, or substance, where the property has a magnitude that can be
expressed as a number and a reference
Note 1 to entry: A reference can be a measurement unit, a measurement procedure, a reference material, or a
combination of such.
EXAMPLE Pressure, P
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[SOURCE: ISO/IEC Guide 99:2007, 1.1, modified — The admitted term “parameter” has been added.
All Notes have been removed except Note 2 to entry, renumbered as Note 1 to entry. The Example has
been added.]
3.2
derived quantity
quantity (3.1) that has been calculated from one or more measurements of other quantities
[8]
EXAMPLE Absolute salinity, S , is calculated from conductivity, temperature and pressure (IOC 56:2010) .
A
3.3
quantity value
value
number and reference together, expressing magnitude of a quantity (3.1)
EXAMPLE 1 Conductivity of a volume of seawater: 35 mS/cm or 3, 5 S/m
EXAMPLE 2 Sound speed of a volume of seawater: 1 500 m/s
[SOURCE: ISO/IEC Guide 99:2007, 1.19, modified — All Examples and Notes have been removed. New
Examples 1 and 2 have been added.]
3.4
measurand
quantity (3.1) intended to be measured
Note 1 to entry: The specification of a measurand requires knowledge of the kind of quantity, description of the
state of the phenomenon, body, or substance carrying the quantity, including any relevant component, and the
chemical entities involved.
Note 2 to entry: In the second edition of the VIM and in IEC 60050-300:2001, the measurand is defined as the
'particular quantity subject to measurement'.
Note 3 to entry: The measurement, including the measuring system and the conditions under which the
measurement is carried out, might change the phenomenon, body, or substance such that the quantity being
measured may differ from the measurand as defined. In this case, adequate correction is necessary.
EXAMPLE 1 The conductivity of a volume of seawater with the ambient Celsius temperature of 23 °C will be
different from the conductivity at the specified temperature of 20 °C, which is the measurand. In this case, a
correction is necessary.
EXAMPLE 2 The length of a steel rod in equilibrium with the ambient Celsius temperature of 23 °C will be
different from the length at the specified temperature of 20 °C, which is the measurand. In this case, a correction
is necessary.
[SOURCE: ISO/IEC Guide 99:2007, 2.3, modified — Note 4 has been removed. Example 2 has been
changed.]
3.5
measurement
process of experimentally obtaining one or more quantity values (3.3) that can reasonably be attributed
to a quantity (3.1)
[SOURCE: ISO/IEC Guide 99:2007, 2.1, modified — All Notes have been removed.]
3.6
measurement unit
unit
real scalar quantity (3.1), defined and adopted by convention, with which any other quantity of the same
kind can be compared to express the ratio of the two quantities as a number
Note 1 to entry: Measurement units are designated by conventionally assigned names and symbols.
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Note 2 to entry: Measurement units of quantities of the same quantity dimension may be designated by the
same name and symbol even when the quantities are not of the same kind. For example, joule per kelvin and
J/K are respectively the name and symbol of both a measurement unit of heat
...