SIST EN IEC 60601-2-37:2025

SLOVENSKI STANDARD
01-januar-2025
Medicinska električna oprema - 2-37. del: Posebne zahteve za osnovno varnost in
bistvene lastnosti ultrazvočne medicinske diagnostične in nadzorovalne opreme
(IEC 60601-2-37:2024)
Medical electrical equipment - Part 2-37: Particular requirements for the basic safety and
essential performance of ultrasonic medical diagnostic and monitoring equipment (IEC
60601-2-37:2024)
Medizinische elektrische Geräte - Teil 2-37: Besondere Festlegungen für die Sicherheit
einschließlich der wesentlichen Leistungsmerkmale von Ultraschallgeräten für die
medizinische Diagnose und Überwachung (IEC 60601-2-37:2024)
Appareils électromédicaux - Partie 2-37: Exigences particulières pour la sécurité de base
et les performances essentielles des appareils de diagnostic et de surveillance médicaux
à ultrasons (IEC 60601-2-37:2024)
Ta slovenski standard je istoveten z: EN IEC 60601-2-37:2024
ICS:
11.040.55 Diagnostična oprema Diagnostic equipment
17.140.50 Elektroakustika Electroacoustics
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 60601-2-37

NORME EUROPÉENNE
EUROPÄISCHE NORM November 2024
ICS 11.040.55; 17.140.50 Supersedes EN 60601-2-37:2008; EN 60601-2-
37:2008/A11:2011; EN 60601-2-37:2008/A1:2015
English Version
Medical electrical equipment - Part 2-37: Particular requirements
for the basic safety and essential performance of ultrasonic
medical diagnostic and monitoring equipment
(IEC 60601-2-37:2024)
Appareils électromédicaux - Partie 2-37: Exigences Medizinische elektrische Geräte - Teil 2-37: Besondere
particulières pour la sécurité de base et les performances Festlegungen für die Sicherheit einschließlich der
essentielles des appareils de diagnostic et de surveillance wesentlichen Leistungsmerkmale von Ultraschallgeräten für
médicaux à ultrasons die medizinische Diagnose und Überwachung
(IEC 60601-2-37:2024) (IEC 60601-2-37:2024)
This European Standard was approved by CENELEC on 2024-10-16. 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 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 CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Türkiye and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2024 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 60601-2-37:2024 E

European foreword
The text of document 62B/1318/CDV, future edition 3 of IEC 60601-2-37, prepared by SC 62B
"Medical imaging equipment, software, and systems" of IEC/TC 62 "Medical equipment, software, and
systems" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2025-11-30
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2027-11-30
document have to be withdrawn
This document supersedes EN 60601-2-37:2008 and all of its amendments and corrigenda (if any).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
Any feedback and questions on this document should be directed to the users’ national committee. A
complete listing of these bodies can be found on the CENELEC website.
Endorsement notice
The text of the International Standard IEC 60601-2-37:2024 was approved by CENELEC as a
European Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standard indicated:
IEC 61157:2007 NOTE Approved as EN 61157:2007 (not modified)
IEC 61157:2007/A1:2013 NOTE Approved as EN 61157:2007/A1:2013 (not modified)
IEC 60601-1-11:2015 NOTE Approved as EN 60601-1-11:2015 (not modified)
IEC 60601-1-11:2015/A1:2020 NOTE Approved as EN 60601-1-11:2015/A1:2021 (not modified)
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
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.
NOTE 1  Where an International Publication has been modified by common modifications, indicated by (mod),
the relevant EN/HD applies.
NOTE 2  Up-to-date information on the latest versions of the European Standards listed in this annex is available
here: www.cencenelec.eu.
Clause 2 of EN 60601-1:2006, EN 60601-1:2006/AC:2010, EN 60601-1:2006/A1:2013, EN 60601-
1:2006/A1:2013/AC:2014, EN 60601-1:2006/A12:2014, EN 60601-1:2006/A2:2021, EN 60601-
1:2006/AC:2022 and EN 60601-1:2006/A13:2024 is applicable, except as follows:
Add the following references:
Publication Year Title EN/HD Year
IEC 60601-1 2005 Medical electrical equipment - Part 1: EN 60601-1 2006
General requirements for basic safety and
essential performance
- - + AC 2010
+ A1 2012 + A1 2013
- - + AC 2014
- - + A12 2014
+ A2 2020 + A2 2021
- - + AC 2022
- - + A13 2024
IEC 60601-1-12 2014 Medical electrical equipment - Part 1-12: EN 60601-1-12 2015
General requirements for basic safety and
essential performance - Collateral Standard:
Requirements for medical electrical
equipment and medical electrical systems
intended for use in the emergency medical
services environment
+ A1 2020 + A1 2020
IEC 60601-2-18 2009 Medical electrical equipment - Part 2-18: EN 60601-2-18 2015
Particular requirements for the basic safety
and essential performance of endoscopic
equipment
IEC 62127-1 2022 Ultrasonics - Hydrophones - Part 1: EN IEC 62127-1 2022
Measurement and characterization of
medical ultrasonic fields
Publication Year Title EN/HD Year
IEC 62359 2010 Ultrasonics - Field characterization - Test EN 62359 2011
methods for the determination of thermal
and mechanical indices related to medical
diagnostic ultrasonic fields
+ A1 2017 + A1 2018
CISPR 11 2024 Industrial, scientific and medical equipment - EN 55011 —
Radio-frequency disturbance characteristics
- Limits and methods of measurement

Under preparation. Stage at the time of publication: FprEN 55011:2023.
IEC 60601-2-37 ®
Edition 3.0 2024-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Medical electrical equipment –

Part 2-37: Particular requirements for the basic safety and essential performance

of ultrasonic medical diagnostic and monitoring equipment

Appareils électromédicaux –
Partie 2-37: Exigences particulières pour la sécurité de base et les performances

essentielles des appareils de diagnostic et de surveillance médicaux à ultrasons

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 11.040.55, 17.140.50 ISBN 978-2-8322-8920-4

– 2 – IEC 60601-2-37:2024 © IEC 2024
CONTENTS
FOREWORD . 4
INTRODUCTION . 7
201.1 Scope, object and related standards . 8
201.2 Normative references . 10
201.3 Terms and definitions . 10
201.4 General requirements . 17
201.5 General requirements for testing ME EQUIPMENT . 18
201.6 Classification of ME EQUIPMENT and ME SYSTEMS . 18
201.7 ME EQUIPMENT identification, marking and documents . 18
201.8 Protection against electrical HAZARDS from ME EQUIPMENT . 23
201.9 Protection against MECHANICAL HAZARDS of ME EQUIPMENT and ME SYSTEMS . 23
201.10 Protection against unwanted and excessive radiation HAZARDS . 23
201.11 Protection against excessive temperatures and other HAZARDS . 24
201.12 Accuracy of controls and instruments and protection against hazardous
outputs . 29
201.13 HAZARDOUS SITUATIONS and fault conditions for ME EQUIPMENT . 31
201.14 PROGRAMMABLE ELECTRICAL MEDICAL SYSTEMS (PEMS) . 31
201.15 Construction of ME EQUIPMENT . 31
201.16 ME SYSTEMS . 31
201.17 *Electromagnetic compatibility of ME EQUIPMENT and ME SYSTEMS . 31
202 ELECTROMAGNETIC DISTURBANCES – Requirements and tests . 31
212 Requirements for medical electrical equipment and medical electrical
systems intended for use in the emergency medical services environment
(EMS) . 33
Annexes . 34
Annex AA (informative) Particular guidance and rationale . 35
Annex BB (informative) Guidance in classification according to CISPR 11 . 43
Annex CC (informative) Guidance to the MANUFACTURER on the interpretation of TI and
MI to be used to inform the OPERATOR . 44
Annex DD (informative) Example set-up to measure surface temperature of externally
applied TRANSDUCER ASSEMBLIES . 48
Annex EE (informative) Acoustic output table intended for third parties . 51
Bibliography . 54
Index of defined terms . 58

Figure AA.1 – Method a) for an external probe . 38
Figure AA.2 – Method b) for an external probe . 39
Figure AA.3 – Method b) for an external probe . 39
Figure DD.1 – Set-up of an example test object to measure the surface temperature of
externally applied transducers . 50

Table 201.101 – List of symbols . 16
Table 201.102 – Distributed essential performance requirements . 18

IEC 60601-2-37:2024 © IEC 2024 – 3 –
Table 201.103 – Acoustic output reporting table . 22
Table 201.104 – Overview of the tests noted under 201.11.1.3 . 28
Table CC.1 – Relative importance of maintaining low exposure indices in various
scanning situations . 46
Table DD.1 – Acoustic and thermal properties of tissues and materials . 48
Table DD.2 – Weight % pure components . 49
Table EE.1 – Example of acoustic output table for third parties . 52

– 4 – IEC 60601-2-37:2024 © IEC 2024
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MEDICAL ELECTRICAL EQUIPMENT –

Part 2-37: Particular requirements for the basic safety
and essential performance of ultrasonic medical
diagnostic and monitoring equipment

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as "IEC Publication(s)"). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
may be required to implement this document. However, implementers are cautioned that this may not represent
the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
IEC 60601-2-37 has been prepared by subcommittee 62B: Medical imaging equipment,
software, and systems, of IEC technical committee 62: Medical equipment, software, and
systems. It is an International Standard.
This third edition cancels and replaces the second edition published in 2007 and
Amendment 1:2015. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) technical and editorial changes resulting from the amended general standard
IEC 60601-1:2005, IEC 60601-1:2005/AMD1:2012 and IEC 60601-1:2005/AMD2:2020 and
its collateral standards IEC 60601-1-xx,

IEC 60601-2-37:2024 © IEC 2024 – 5 –
b) technical and editorial changes as a result of maintenance to normative references;
c) technical and editorial changes resulting from relevant developments in TC 87 Ultrasonics
standards. In particular, Clause 201.11 about protection against excessive temperatures
and other hazards has been fully revised.
The text of this International Standard is based on the following documents:
Draft Report on voting
62B/1318/CDV 62B/1348/RVC
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
In this document, the following print types are used:
– requirements and definitions: roman type.
– test specifications: italic type.
– informative material appearing outside of tables, such as notes, examples and references: in smaller type.
Normative text of tables is also in a smaller type.
– TERMS DEFINED IN CLAUSE 3 OF IEC 60601-1:2005, IEC 60601-1:2005/AMD1:2012 and
IEC 60601-1:2005/AMD2:2020, IN THIS DOCUMENT OR AS NOTED: SMALL CAPITALS.
In referring to the structure of this document, the term
– "clause" means one of the seventeen numbered divisions within the table of contents,
inclusive of all subdivisions (e.g. Clause 7 includes subclauses 7.1, 7.2, etc.);
– "subclause" means a numbered subdivision of a clause (e.g. 7.1, 7.2 and 7.2.1 are all
subclauses of Clause 7).
References to clauses within this document are preceded by the term "Clause" followed by the
clause number. References to subclauses within this document are by number only.
In this document, the conjunctive "or" is used as an "inclusive or" so a statement is true if any
combination of the conditions is true.
The verbal forms used in this document conform to usage described in Clause 7 of the ISO/IEC
Directives, Part 2. For the purposes of this document, the auxiliary verb:
– "shall" means that compliance with a requirement or a test is mandatory for compliance with
this document;
– "should" means that compliance with a requirement or a test is recommended but is not
mandatory for compliance with this document;
– "may" is used to describe a permissible way to achieve compliance with a requirement or
test.
An asterisk (*) as the first character of a title or at the beginning of a paragraph or table title
indicates that there is guidance or rationale related to that item in Annex AA.
A list of all parts of the IEC 60601 series, published under the general title: Medical electrical
equipment, can be found on the IEC website

– 6 – IEC 60601-2-37:2024 © IEC 2024
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
IMPORTANT – The "colour inside" logo on the cover page of this document indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this document using a colour printer.

IEC 60601-2-37:2024 © IEC 2024 – 7 –
INTRODUCTION
In this document, safety requirements additional to those in IEC 60601-1:2005,
IEC 60601-1:2005/AMD1:2012, and IEC 60601-1:2005/AMD2:2020 are specified for
ULTRASONIC DIAGNOSTIC EQUIPMENT.
A general guidance and rationale for the requirements of this document are given in Annex AA.
Knowledge of the reasons for these requirements will not only facilitate the proper application
of this document but will, in due course, expedite any revision necessitated by changes in
clinical practice or as a result of developments in technology.
The approach and philosophy used in drafting this document for safety of ULTRASONIC
DIAGNOSTIC EQUIPMENT are consistent with those in standards of the IEC 60601-2 series that
apply to other diagnostic modalities, such as X-ray equipment and magnetic resonance systems.
In each case, the safety standard is intended to require increasing sophistication of output
display indicators and controls with increasing energy levels in the interrogating field of
diagnosis. Thus, for all such diagnostic modalities, it is the responsibility of the OPERATOR to
understand the risk of the output of the ULTRASONIC DIAGNOSTIC EQUIPMENT, and to act
appropriately in order to obtain the needed diagnostic information with the minimum risk to the
PATIENT.
– 8 – IEC 60601-2-37:2024 © IEC 2024
MEDICAL ELECTRICAL EQUIPMENT –

Part 2-37: Particular requirements for the basic safety
and essential performance of ultrasonic medical
diagnostic and monitoring equipment

201.1 Scope, object and related standards
Clause 1 of IEC 60601-1:2005, IEC 60601-1:2005/AMD1:2012, and
IEC 60601-1:2005/AMD2:2020 applies, except as follows:
201.1.1 *Scope
Replacement:
This document applies to the BASIC SAFETY and ESSENTIAL PERFORMANCE of ULTRASONIC
DIAGNOSTIC EQUIPMENT as defined in 201.3.217, hereinafter referred to as ME EQUIPMENT.
If a clause or subclause is specifically intended to be applicable to ME EQUIPMENT only, or to
ME SYSTEMS only, the title and content of that clause or subclause will say so. If that is not the
case, the clause or subclause applies both to ME EQUIPMENT and to ME SYSTEMS, as relevant.
HAZARDS inherent in the intended physiological function of ME EQUIPMENT or ME SYSTEMS within
the scope of this document are not covered by specific requirements in this document except
in 201.7.2.13.
This document does not cover ultrasonic therapeutic equipment. Equipment used for the
imaging or diagnosis of body structures by ultrasound in conjunction with other medical
procedures is covered.
201.1.2 Object
Replacement:
The object of this document is to establish particular BASIC SAFETY and ESSENTIAL PERFORMANCE
requirements for ULTRASONIC DIAGNOSTIC EQUIPMENT as defined in 201.3.217.
201.1.3 Collateral standards
Addition:
This document refers to those applicable collateral standards that are listed in Clause 2 of
IEC 60601-1:2005, IEC 60601-1:2005/AMD1:2012 and IEC 60601-1:2005/AMD2:2020 and
Clause 201.2 of this document.
IEC 60601-1-2:2014, IEC 60601-1-2:2014/AMD1:2020, IEC 60601-1-12:2014 and
IEC 60601-1-12:2014/AMD1:2020 apply as modified in Clause 202 and Clause 212 respectively.
All other published collateral standards in the IEC 60601-1 series apply as published.

IEC 60601-2-37:2024 © IEC 2024 – 9 –
201.1.4 Particular standards
Replacement:
In the IEC 60601 series, particular standards may modify, replace or delete requirements
contained in IEC 60601-1:2005, IEC 60601-1:2005/AMD1:2012 and
IEC 60601-1:2005/AMD2:2020 as appropriate for the particular ME EQUIPMENT under
consideration, and may add other BASIC SAFETY and ESSENTIAL PERFORMANCE requirements.
A requirement of a particular standard takes priority over IEC 60601-1:2005,
IEC 60601-1:2005/AMD1:2012 and IEC 60601-1:2005/AMD2:2020.
The numbering of sections, clauses and subclauses of this document corresponds to that of
IEC 60601-1:2005, IEC 60601-1:2005/AMD1:2012 and IEC 60601-1:2005/AMD2:2020 with the
prefix "201" (e.g. 201.1 in this document addresses the content of Clause 1 of
IEC 60601-1:2005, IEC 60601-1:2005/AMD1:2012 and IEC 60601-1:2005/AMD2:2020) or
applicable collateral standard with the prefix "20x" where x is the final digit(s) of the collateral
standard document number (e.g. 202.6 in this document addresses the content of Clause 6 of
the IEC 60601-1-2 collateral standard, 203.4 in this document addresses the content of Clause
4 of the IEC 60601-1-3 collateral standard, etc.). The changes to the text of IEC 60601-1:2005,
IEC 60601-1:2005/AMD1:2012 and IEC 60601-1:2005/AMD2:2020 are specified by the use of
the following words:
"Replacement" means that the clause or subclause of IEC 60601-1:2005,
IEC 60601-1:2005/AMD1:2012 and IEC 60601-1:2005/AMD2:2020 or applicable collateral
standard is replaced completely by this document.
"Addition" means that the text of this document is additional to the requirements of
IEC 60601-1:2005, IEC 60601-1:2005/AMD1:2012 and IEC 60601-1:2005/AMD2:2020 or
applicable collateral standard.
"Amendment" means that the clause or subclause of IEC 60601-1:2005,
IEC 60601-1:2005/AMD1:2012 and IEC 60601-1:2005/AMD2:2020 or applicable collateral
standard is amended as indicated by the text of this document.
Subclauses, figures or tables which are additional to those of the general standard are
numbered starting from 201.101. However, due to the fact that definitions in the general
standard are numbered 3.1 through 3.154, additional definitions in this document are numbered
beginning from 201.3.201. Additional annexes are lettered AA, BB, etc., and additional items
aa), bb), etc.
Subclauses or figures which are additional to those of a collateral standard are numbered
starting from 20x, where "x" is the number of the collateral standard, e.g. 202 for IEC 60601-1-2,
203 for IEC 60601-1-3, etc.
The term "this document" is used to make reference to the IEC 60601-1:2005,
IEC 60601-1:2005/AMD1:2012 and IEC 60601-1:2005/AMD2:2020, any applicable collateral
standards and this document taken together.
Where there is no corresponding section, clause or subclause in this document, the section,
clause or subclause of IEC 60601-1:2005, IEC 60601-1:2005/AMD1:2012 and
IEC 60601-1:2005/AMD2:2020 or applicable collateral standard, although possibly not relevant,
applies without modification; where it is intended that any part of IEC 60601-1:2005,
IEC 60601-1:2005/AMD1:2012 and IEC 60601-1:2005/AMD2:2020 or applicable collateral
standard, although possibly relevant, is not to be applied, a statement to that effect is given in
this document.
– 10 – IEC 60601-2-37:2024 © IEC 2024
201.2 Normative references
Clause 2 of IEC 60601-1:2005, IEC 60601-1:2005/AMD1:2012 and
IEC 60601-1:2005/AMD2:2020 applies except as follows:
Addition:
IEC 60601-1:2005, Medical electrical equipment – Part 1: General requirements for basic safety
and essential performance
IEC 60601-1:2005/AMD1:2012
IEC 60601-1:2005/AMD2:2020
IEC 60601-1-12:2014, Medical electrical equipment – Part 1-12: General requirements for basic
safety and essential performance – Collateral Standard: Requirements for medical electrical
equipment and medical electrical systems intended for use in the emergency medical services
environment
IEC 60601-1-12:2014/AMD1:2020
IEC 60601-2-18:2009, Medical electrical equipment – Part 2-18: Particular requirements for the
basic safety and essential performance of endoscopic equipment
IEC 62127-1:2022, Ultrasonics – Hydrophones – Part 1: Measurement and characterization of
medical ultrasonic fields
IEC 62359:2010, Ultrasonics – Field characterization – Test methods for the determination of
thermal and mechanical indices related to medical diagnostic ultrasonic fields
IEC 62359:2010/AMD1:2017
CISPR 11:2024, Industrial, scientific and medical equipment – Radio-frequency disturbance
characteristics – Limits and methods of measurement
201.3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60601-1:2005,
IEC 60601-1:2005/AMD1:2012 and IEC 60601-1:2005/AMD2:2020 and in IEC 62359 and the
following apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
NOTE 1 An index of defined terms is given after the Bibliography.
NOTE 2 A list of symbols used in this document is found in Table 201.101.

IEC 60601-2-37:2024 © IEC 2024 – 11 –
Addition:
201.3.201
BONE THERMAL INDEX
TIB
THERMAL INDEX for applications such as foetal (second and third trimester), in which the
ultrasound beam passes through soft tissue and a focal region is in the immediate vicinity of
bone
Unit: None
[SOURCE: IEC 62359:2010 and IEC 62359:2010/AMD1:2017, 3.17, modified – The original
notes have been deleted.]
201.3.202
COMBINED-OPERATING MODE
mode of operation of ULTRASONIC DIAGNOSTIC EQUIPMENT that combines more than one DISCRETE-
OPERATING MODE
201.3.203
CRANIAL-BONE THERMAL INDEX
TIC
THERMAL INDEX for applications, in which the ultrasound beam passes through bone near the
beam entrance into the body, such as paediatric and adult cranial or neonatal cephalic
applications
Unit: None
[SOURCE: IEC 62359:2010 and IEC 62359:2010/AMD1:2017, 3.21, modified – The original
notes have been deleted.]
201.3.204
DEFAULT SETTING
specific state of control the ULTRASONIC DIAGNOSTIC EQUIPMENT will enter upon power-up, new
PATIENT select, or change from non-foetal to foetal applications
201.3.205
DISCRETE-OPERATING MODE
mode of operation of ULTRASONIC DIAGNOSTIC EQUIPMENT in which the purpose of the excitation
of the ULTRASONIC TRANSDUCER or ULTRASONIC TRANSDUCER element group is to utilise only one
diagnostic methodology
201.3.206
FULL SOFTWARE CONTROL OF ACOUSTIC OUTPUT
means by which the ULTRASONIC DIAGNOSTIC EQUIPMENT manages the acoustic output
independent of direct OPERATOR control
201.3.207
INVASIVE TRANSDUCER ASSEMBLY
transducer which, in whole or in part, penetrates inside the body, either through a body orifice
or through the surface of the body

– 12 – IEC 60601-2-37:2024 © IEC 2024
201.3.208
MECHANICAL INDEX
Indicator of the risk for bioeffects due to mechanical or nonthermal mechanisms, such as
cavitation
Symbol: MI
Unit: None
Note 1 to entry: See IEC 62359 for methods of determining the MECHANICAL INDEX.
201.3.209
MULTI-PURPOSE ULTRASONIC DIAGNOSTIC EQUIPMENT
ULTRASONIC DIAGNOSTIC EQUIPMENT that is intended for more than one clinical application
201.3.210
NON-SCANNING MODE
mode of operation of ULTRASONIC DIAGNOSTIC EQUIPMENT that involves a sequence of ultrasonic
pulses that give rise to ultrasonic scan lines that follow the same acoustic path
201.3.211
PRUDENT USE STATEMENT
affirmation of the principle that only necessary clinical information should be acquired and that
high exposure levels and long exposure times should be avoided
[SOURCE: IEC 62359:2010 and IEC 62359:2010/AMD1:2017, 3.40]
201.3.212
SCANNING MODE
mode of operation of ULTRASONIC DIAGNOSTIC EQUIPMENT that involves a sequence of ultrasonic
pulses that give rise to scan lines that do not follow the same acoustic path
201.3.213
SOFT TISSUE THERMAL INDEX
TIS
THERMAL INDEX related to soft tissues
Unit: None
[SOURCE: IEC 62359:2010, 3.52, modified – The original notes have been deleted.]
201.3.214
THERMAL INDEX
TI
indicator of the risk of bioeffect due to thermal mechanisms expressed as the ratio of
ATTENUATED OUTPUT POWER at a specified point to the ATTENUATED OUTPUT POWER required to
raise the temperature at that point in a specific tissue model by 1 °C
Unit: None
[SOURCE: IEC 62359:2010 and IEC 62359:2010/AMD1:2017, 3.56, modified – Addition of
“indicator of the risk of bioeffect due to thermal mechanisms expressed as the”, and the original
note has been deleted.]
IEC 60601-2-37:2024 © IEC 2024 – 13 –
201.3.215
TRANSDUCER ASSEMBLY
those parts of ULTRASONIC DIAGNOSTIC EQUIPMENT comprising either the ULTRASONIC TRANSDUCER
and the ULTRASONIC TRANSDUCER ELEMENT GROUP, or both, together with any integral
components, such as an acoustic lens or integral stand-off
Note 1 to entry: The TRANSDUCER ASSEMBLY is usually separable from the ultrasound instrument console.
[SOURCE: IEC 62359:2010 and IEC 62359:2010AMD1:2017, 3.57, modified – "medical
diagnostic ultrasound equipment" has been replaced by "ULTRASONIC DIAGNOSTIC EQUIPMENT" in
the definition.]
201.3.216
TRANSMIT PATTERN
combination of a specific set of transducer beam-forming characteristics (determined by the
transmit aperture size, apodisation shape, and relative timing/phase delay pattern across the
aperture, resulting in a specific focal length and direction), and an electrical drive waveform of
a specific fixed shape but variable amplitude
[SOURCE: IEC 62359:2010, 3.58]
201.3.217
ULTRASONIC DIAGNOSTIC EQUIPMENT
MEDICAL ELECTRICAL EQUIPMENT that is intended for ultrasonic medical examination
201.3.218
ULTRASONIC TRANSDUCER
device capable of converting electrical energy to mechanical energy within the ultrasonic
frequency range and reciprocally of converting mechanical energy to electrical energy
[SOURCE: IEC 62127-1:2022, 3.88]
201.3.219
ATTENUATED PULSE-AVERAGE INTENSITY
I
pa,α
value of the acoustic PULSE-AVERAGE INTENSITY after attenuation and at a specified point, and
given by
−αzf /10dB
( )
awf
(1)
I zI= z 10
( ) ( )
pa,α pa
where
α is the ACOUSTIC ATTENUATION COEFFICIENT as defined in IEC 62359:2010, definition 3.1;
z is the distance from the EXTERNAL TRANSDUCER APERTURE to the point of interest;
f is the ACOUSTIC WORKING FREQUENCY as defined in IEC 62359:2010 and
awf
IEC 62359:2010/AMD1:2017, definition 3.4;
I (z) is the PULSE-AVERAGE INTENSITY measured in water as defined in IEC 62127-1:2022,
pa
3.53.
–2
Unit: W m
– 14 – IEC 60601-2-37:2024 © IEC 2024
201.3.220
NUMBER OF PULSES PER ULTRASONIC SCAN LINE
n
pps
number of acoustic pulses travelling along a particular ULTRASONIC SCAN LINE
Note 1 to entry: Here ULTRASONIC SCAN LINE refers to the path of acoustic pulses on a particular BEAM AXIS in
SCANNING and NON-SCANNING MODES.
Note 2 to entry: This number can be used in the calculation of any ultrasound temporal average value from
HYDROPHONE measurements.
Note 3 to entry: The following shows an example of the NUMBER OF PULSES PER ULTRASONIC SCAN LINE and the
NUMBER OF ULTRASONIC SCAN LINES (";" indicates the end of a frame):
1 2 3 4; 1 2 3 4; 1 2 3 4… n = 1; n = 4
pps sl
1 1 2 2 3 3 4 4; 1 1 2 2 3 3 4 4; … n = 2; n = 4
pps sl
1 1 1 1 2 2 2 2 3 3 3 3 4 4 4 4; 1 1 1 1 2 2 2 2 3 3 3 3 4 4 4 4; … n = 4; n = 4
pps sl
1 1 2 2 3 3 4 4 1 1 1 2 2 2 3 3 3 4 4 4; 1 1 2 2 3 3 4 4 1 1 1 2 2 2 3 3 3 4 4 4; … n = 5; n = 4 (within one frame
pps sl
the pulses down each line may not occur contiguously).
Within one frame, all scan lines may not have the same n value. An example is: 1 2 2 3 3 4; 1 2 2 3 3 4; … avg
pps
n = 1,5; max n = 2; n = 4
pps pps sl
[SOURCE: IEC 61157:2007/AMD1:2013, 3.45, modified – The fourth example in the Note 3 to
entry has been corrected.]
201.3.221
ULTRASOUND ENDOSCOPE
ENDOSCOPE with built-in ULTRASOUND TRANSDUCERS
201.3.222
ENDOSCOPE
medical instrument having viewing means, with or without optics, introduced into a body cavity
through a natural or surgically created body opening for examination, diagnosis or therapy
Note 1 to entry: ENDOSCOPES may be of rigid, flexible or capsule type, each of which may have different image
pick-up systems (e.g. via lenses or electronic/ultrasonic sensors) and different image transmission systems (e.g.
optical (via lenses or fibre bundles), or electrical/electronic).
Note 2 to entry: Note 1 to entry differs from NOTE 1 of definition 3.1 in ISO 8600-1 in order to include 'capsule'
endoscopes.
[SOURCE: IEC 60601-2-18:2009, 201.3.203]
201.3.223
DEPTH FOR PEAK PULSE-INTENSITY INTEGRAL
z
pii
depth z on the BEAM AXIS and beyond the BREAK-POINT DEPTH z from the external transducer
bp
aperture to the plane of maximum PULSE-INTENSITY INTEGRAL (pii) as approximated by the PULSE-
PRESSURE-SQUARED INTEGRAL (ppsi)
[SOURCE: IEC 62359:2010 and IEC 62359:2010/AMD1:2017, 3.24, modified ─ Notes to entry
1, 2 and 3 deleted.]
IEC 60601-2-37:2024 © IEC 2024 – 15 –
201.3.224
DEPTH FOR PEAK ATTENUATED PULSE-INTENSITY INTEGRAL
z
pii, α
depth z on the BEAM AXIS and beyond the BREAK-POINT DEPTH z of peak ATTENUATED PULSE-
bp
INTENSITY INTEGRAL
Unit: m
Note 1 to entry: BEAM-AXIS and BREAK-POINT DEPTH are defined in IEC 62359.
[SOURCE: IEC 62359:2010 and IEC 62359:2010/AMD1:2017, 3.71, modified ─ Main term
“depth for maximum ” replaced with “depth for peak attenuated pulse-intensity integral”,
pii, α
Notes to entry 1, 2 and 3 deleted and addition of a new Note to entry. ]
201.3.225
DEPTH FOR PEAK SUM OF PULSE-INTENSITY INTEGRALS
z
sii
depth z on the BEAM AXIS and beyond the BREAK-POINT DEPTH z of peak SCAN-INTENSITY
bp
INTEGRAL
Unit: m
Note 1 to entry: BEAM-AXIS and BREAK-POINT DEPTH are defined in IEC 62359.
Note 2 to entry: The subscript 'sii' indicates the scan intensity integral (sii). The sii for SCANNING MODE components
at a particular point is determined from the sum over a complete scan frame of the PULSE-INTENSITY INTEGRALS of the
ULTRASONIC SCAN LINES that make up the scanning components of a combined mode. Non-scanned components are
excluded from the sum. See IEC 62359 and IEC 62127-1 for more details.
[SOURCE: IEC 62359:2010 and IEC 62359:2010/AMD1:2017, 3.74, modified ─ Main term
“depth for maximum sii” replaced with “depth for peak sum of pulse-intensity integrals”, Notes
to entry 1, 2 and 3 deleted and addition of new Notes 1 and 2 to entry.]
201.3.226
DEPTH FOR PEAK SUM OF ATTENUATED PULSE-INTENSITY INTEGRALS
z
sii,α
depth z on the BEAM AXIS and beyond the BREAK-POINT DEPTH z of peak ATTENUATED SCAN-
bp
INTENSITY INTEGRAL
Unit: m
Note 1 to entry: BEAM-AXIS and BREAK-POINT DEPTH are defined in IEC 62359.
Note 2 to entry: The subscript "sii" indicates the "scan intensity integral" that is the sum at a particular point of the
PULSE-INTENSITY INTEGRALS of the ULTRASONIC SCAN LINES comprising a SCANNING MODE component. See IEC 62359
and IEC 62127-1 for additional details.
[SOURCE: IEC 62359:2010 and IEC 62359:2010/AMD1:2017, 3.75, modified ─ Main term
“depth for maximum sii ” replaced with “depth for peak sum of attenuated pulse-intensity
α
integrals”, addition of “peak” in the definition, Notes to entry 1, 2 and 3 deleted and addition of
new Notes 1 and 2 to entry.]
– 16 – IEC 60601-2-37:2024 © IEC 2024
201.3.227
DEPTH FOR MECHANICAL INDEX
z
MI
depth on the BEAM-AXIS from the EXTERNAL TRANSDUCER APERTURE to the plane of maximum
ATTENUATED PULSE-PRESSURE-SQUARED-INTEGRAL (ppsi )
α
Unit: m
[SOURCE: IEC 62359:2010 and IEC 62359:2010/AMD1:2017, 3.23]
201.3.228
THERMAL OFFSET
∆T
offset
difference between a) the temperature of the APPLIED PART of the TRANSDUCER ASSEMBLY at
steady-state in the measurement setting before transmitting begins and b) the steady-state
TRANSDUCER ASSEMBLY
temperature at the same location in the measurement setting when the
was not present
Note 1 to entry: The value of the THERMAL OFFSET can be positive, negative or zero.
201.3.229
ULTRASOUND
acoustic oscillation whose frequency is above the high-frequency limit of audible sound (about
20 kHz)
[SOURCE: IEC 60050-802:2011, 802-01-01]
Table 201.101 – List of symbols
Symbol Term Reference
A = –12 dB OUTPUT BEAM AREA IEC 62359
aprt
d = EQUIVALENT BEAM DIAMETER IEC 62359
eq
f = ACOUSTIC WORKING FREQUENCY IEC 62359
awf
I = ATTENUATED PULSE-AVERAGE INTENSITY
pa,α
pii = PULSE-INTENSITY INTEGRAL IEC 62359
pii = ATTENUATED PULSE-INTENSITY INTEGRAL IEC 62359
α
I = ATTENUATED SPATIAL-PEAK PULSE-AVERAGE INTENSITY IEC 62359
sppa,α
I = SPATIAL-PEAK TEMPORAL-AVERAGE INTENSITY IEC 62359
spta
I = ATTENUATED SPATIAL-PEAK TEMPORAL-AVERAGE INTENSITY IEC 62359
spta,α
I (z) = ATTENUATED TEMPORAL-AVERAGE INTENSITY IEC 62359
ta,α
MI = MECHANICAL INDEX IEC 62359
n = NUMBER OF PULSES PER ULTRASONIC SCAN LINE IEC 61157
pps
P = OUTPUT POWER IEC 62359
P = BOUNDED-SQUARE OUTPUT POWER IEC 62359
1x1
P = ATTENUATED OUTPUT POWER IEC 62359
α
p = ATTENUATED PEAK-RAREFACTIONAL ACOUSTIC PRESSURE IEC 62359
r,α
p = PEAK-RAREFACTIONAL ACOUSTIC PRESSURE IEC 62359
r
prr = PULSE REPETITION RATE
...