IEC 62359:2010/AMD1:2017

Amendment 1 - Ultrasonics - Field characterization - Test methods for the determination of thermal and mechanical indices related to medical diagnostic ultrasonic fields

Amendement 1 - Ultrasons - Caractérisation du champ - Méthodes d'essais pour la détermination d'indices thermique et mécanique des champs d'ultrasons utilisés pour le diagnostic médical

General Information

• Status: Published
• Publication Date: 28-Sep-2017
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 17.140.50 - Electroacoustics
• Technical Committee: TC 87 - Ultrasonics
• Drafting Committee: WG 8 - TC 87/WG 8
• Current Stage: PPUB - Publication issued
• Start Date: 14-Oct-2017
• Completion Date: 29-Sep-2017

Relations

• Amends: IEC 62359:2010 - Ultrasonics - Field characterization - Test methods for the determination of thermal and mechanical indices related to medical diagnostic ultrasonic fields
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 62359 ®
Edition 2.0 2017-09
INTERNATIONAL
STANDARD
AMENDMENT 1
Ultrasonics – Field characterization –
Test methods for the determination of thermal and mechanical indices related
to medical diagnostic ultrasonic fields

IEC 62359:2010-10/AMD1:2017-09(en)

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.

IEC Central Office Tel.: [phone]
3, rue de Varembé Fax: [phone]
CH-1211 Geneva 20 [e-mail]
Switzerland www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.

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Technical Specifications, Technical Reports and other English and French, with equivalent terms in 16 additional
documents. Available for PC, Mac OS, Android Tablets and languages. Also known as the International Electrotechnical
iPad. Vocabulary (IEV) online.

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IEC 62359 ®
Edition 2.0 2017-09
INTERNATIONAL
STANDARD
AMENDMENT 1
Ultrasonics – Field characterization –

Test methods for the determination of thermal and mechanical indices related

to medical diagnostic ultrasonic fields

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 17.140.50 ISBN 978-2-8322-4821-8

– 2 – IEC 62359:2010/AMD1:2017
© IEC 2017
FOREWORD
This amendment has been prepared by IEC technical committee 87: Ultrasonics.
The text of this amendment is based on the following documents:
FDIS Report on voting
87/661/FDIS 87/665/RVD
Full information on the voting for the approval of this amendment can be found in the report
on voting indicated in the above table.
The committee has decided that the contents of this amendment and the base publication will
remain unchanged until the stability date indicated on the IEC website under
"http://webstore.iec.ch" in the data related to the specific publication. At this date, the
publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

_____________
Introduction to Amendment
The second edition of IEC 62359 was published in 2010. Since then,
IEC 60601-2-37:2007/AMD1:2015 has been published and calls for provision of attenuated
spatial peak temporal average intensity, I , and attenuated spatial peak pulse
spta,a
average intensity, I , at specific spatial maximum points in the ultrasonic field on the
sppa,a
beam axis. No IEC standard describes the determination of these quantities at these specific
positions. IEC 62359 for determining the thermal indices currently uses similar values at other
positions, therefore, the determination of attenuated spatial peak temporal average
, and attenuated spatial peak pulse average intensity, I , has been
intensity, I
spta,a sppa,a
added as an annex in this amendment.
Additionally, references to newly published collateral standards have been updated.
_____________
© IEC 2017
2 Normative references
Replace the first reference by the following:
IEC 60601-2-37:2007, Medical electrical equipment – Part 2-37: Particular requirements for
the basic safety and essential performance of ultrasonic medical diagnostic and monitoring
equipment
IEC 60601-2-37:2007/AMD1:2015
Replace the second reference by the following:
IEC 61157:2007, Standard means for the reporting of the acoustic output of medical
diagnostic ultrasonic equipment
IEC 61157:2007/AMD1:2013
Replace, in the third reference, "IEC 61161:2006" by "IEC 61161:2013".
Replace the fifth reference by the following:
IEC 62127-1:2007, Ultrasonics – Hydrophones – Part 1: Measurement and characterization of
medical ultrasonic fields up to 40 MHz
IEC 62127-1:2007/AMD1:2013
3 Terms and definitions
Replace the first existing paragraph by the following new paragraph:
For the purposes of this document, the terms and definitions given in IEC 60601-2-37,
IEC 62127-1, IEC 62127-2, IEC 62127-3, IEC 61157 and IEC 61161 apply. Several of these
are repeated below for convenience and others are listed because they have been modified
for application to this standard.
3.3
acoustic repetition period
Replace the existing definition by the following new definition:
time interval between corresponding points of consecutive cycles, pulses or scans, depending
on the current operating mode
Add the following new NOTES 2 and 3:
NOTE 2 For continuous wave modes, the acoustic repetition period is the time interval between corresponding
points of consecutive cycles
NOTE 3 For combined operating modes where transmit pulsing of the constituent modes may be interrupted,
the arp determination should take into account non-pulsing time to calculate an average period.
Replace "NOTE 2" by NOTE 4".
3.4
acoustic working frequency
Replace, in the existing definition, the words "at the position corresponding to the spatial-
peak temporal-peak acoustic pressure" by "on the beam axis, beyond the break-point
depth, corresponding to depth of maximum pulse-intensity integral z ."
pii
Replace, in existing NOTE 2, the words "at the position of maximum pulse-pressure-squared
integral" by "at the depth for peak pulse-intensity integral".

– 4 – IEC 62359:2010/AMD1:2017
© IEC 2017
3.7
attenuated peak-rarefactional acoustic pressure
Replace, in the existing definition, the words "at a specified distance from" by "on a plane
perpendicular to the beam axis at a specified distance z from".
Replace, in the definition list after Equation (2), the words "z is the distance from the external
transducer aperture to the point of interest" by "z is the distance from the external
transducer aperture along the beam axis to the plane containing the point of interest".
3.8
attenuated pulse-intensity integral
Replace, in the definition, the words "at a specified distance from" by "on a plane
perpendicular to the beam axis at a specified distance z from".
Replace, in the definition list after Equation (3), the words "z is the distance from the external
transducer aperture to the point of interest" by "z is the distance from the external
transducer aperture along the beam axis to the plane containing the point of interest".
Replace "NOTE" by "NOTE 1".
Add new NOTE 2:
NOTE 2 For measurement purposes of this standard, pii is equivalent to 1/(ρc) times the attenuated pulse-
α
pressure-squared integral at depth z, with ρc denoting the characteristic acoustic impedance of pure water.
3.9
attenuated spatial-average temporal-average intensity
Replace, in the definition, the words "at a specified distance from" by "on a plane
perpendicular to the beam axis at a specified distance z from".
Replace, in the definition list after Equation (4), the words "z is the distance from the external
transducer aperture to the point of interest" by "z is the distance from the external
transducer aperture along the beam axis to the plane containing the point of interest".
3.10
attenuated spatial-peak temporal-average intensity
Replace, in the definition, the words "at a specified distance from" by "on a plane
perpendicular to the beam axis at a specified distance z from".
Replace, in the definition list after Equation (5), the words "z is the distance from the external
transducer aperture to the point of interest" by "z is the distance from the external
transducer aperture along the beam axis to the plane containing the point of interest".
3.11
attenuated temporal-average intensity
Replace, in the definition, the words "at a specified distance from" by "on a plane
perpendicular to the beam axis at a specified distance z from".
Replace, in the definition list after Equation (6), the words "z is the distance from the external
is the distance from the external
transducer aperture to the point of interest" by "z
transducer aperture along the beam axis to the plane containing the point of interest".
3.13
beam-axis
Replace the term "beam-axis" by "beam axis".

© IEC 2017
3.17
bone thermal index
Delete, in the definition, "or neonatal cephalic (through the fontanelle)".
3.19
break-point depth
Add, after the existing definition, the words "acoustic working frequency and intensity
parameters (such as attenuated spatial-peak temporal-average intensity)"
Add, after "where D is the equivalent aperture diameter" the words "for non-scanning
eq
modes".
Replace the existing NOTE 2 by the following new note:
NOTE 2 For scanning modes, use the non-scanning mode D value calculation [Equation (8)]. Do this using
eq
the output beam area of one ultrasonic scan line; the central scan line, corresponding to the beam axis (i.e. the
line where pii MI, and f are measured).

,
awf
3.21
cranial-bone thermal index
Replace the existing definition by the following new definition:
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
3.22
default setting
Replace, in the definition, "ultrasonic diagnostic equipment" by "medical diagnostic
ultrasonic equipment".
3.23
depth for mechanical index
Replace, in the definition, the words "to the plane of maximum attenuated pulse-intensity
integral (pii )" by "to the plane of maximum attenuated pulse-pressure-squared-integral
a
(ppsi )".
a
Add new NOTE 1:
NOTE 1 Because z may occur closer to the transducer than the break-point depth z , use of ppsi rather than
MI bp α
pii is technically more appropriate. If z is larger than z , then z and z are equal.

α ppsi,α bp ppsi,α pii,α
Replace "NOTE" by "NOTE 2".
3.24
depth for peak pulse-intensity integral
Replace the existing term, definition and note by the following new term, definition and notes:
3.24
depth for maximum pulse intensity integral
depth z on the beam axis and beyond the break-point depth z from the external
bp
transduscer aperture to the plane of maximum pulse-intensity integral (pii) as
approximated by the pulse-pressure-squared integral (ppsi)
NOTE 1 Depth for maximum pii is expressed in metres (m).
NOTE 2 Depth for maximum pii is termed "depth for peak pulse-intensity integral" in
IEC 60601-2-37:2007/AMD1:2015.

– 6 – IEC 62359:2010/AMD1:2017
© IEC 2017
NOTE 3 At this depth the acoustic working frequency is determined.
3.27
Discrete-perating mode
Replace the term "Discrete-perating mode" by "discrete-operating mode".
Replace, in the definition, "ultrasonic diagnostic equipment" by "medical diagnostic
ultrasonic equipment".
3.28
equivalent aperture diameter
Replace the existing definition and equation by the following new definition and equation:
diameter of a circle the area A of which is the –12 dB output beam area A for non-
ob
scanning modes and the –12 dB scanned aperture area A for scanning modes, given by
sa
D = A
(8)
eq
π
Replace the existing NOTE 1 by the following new note:
NOTE 1 Equation (8) is used in the calculation of the cranial-bone thermal index; for non-scanning modes with
A = A and for scanning modes with A = A .
ob sa
Add new NOTE 2:
NOTE 2 Equation (8) with A = A is also used in calculating the break-point depth.
ob
Replace "NOTE 2" by "NOTE 3".
3.33
medical diagnostic ultrasonic equipment
Replace "NOTE" by "NOTE 1".
Add new NOTE 2:
NOTE 2 IEC 60601-2-37:2007 uses the term "ultrasonic diagnostic equipment" instead of medical diagnostic
ultrasonic equipment.
3.34
non-scanning mode
Replace, in the definition, the words "ultrasonic diagnostic equipment" by "medical
diagnostic ultrasonic equipment".
3.37
output power
Replace, in the source, "IEC 61161:2006" by "IEC 61161:2013".
3.40
prudent-use statements
Replace the existing definition by the following new definition:
affirmations of the principle that only necessary clinical information should be acquired and
that high exposure levels and long exposure times should be avoided

© IEC 2017
3.44
pulse repetition period
Add new NOTE 1:
NOTE 1 In general, for non-scanning
...

IEC 62359 ®
Edition 2.0 2017-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
A MENDMENT 1
AM ENDEMENT 1
Ultrasonics – Field characterization – Test methods for the determination of
thermal and mechanical indices related to medical diagnostic ultrasonic fields

Ultrasons – Caractérisation du champ – Méthodes d'essai pour la détermination
d'indices thermique et mécanique des champs d'ultrasons utilisés pour le
diagnostic médical
IEC 62359:2010-10/AMD1:2017-09(en-fr)

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
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Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.

IEC Catalogue - webstore.iec.ch/catalogue Electropedia - www.electropedia.org
The stand-alone application for consulting the entire The world's leading online dictionary of electronic and
bibliographical information on IEC International Standards, electrical terms containing 21 000 terms and definitions in
Technical Specifications, Technical Reports and other English and French, with equivalent terms in 16 additional
documents. Available for PC, Mac OS, Android Tablets and languages. Also known as the International Electrotechnical
iPad. Vocabulary (IEV) online.

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The advanced search enables to find IEC publications by a 67 000 electrotechnical terminology entries in English and
variety of criteria (reference number, text, technical French extracted from the Terms and Definitions clause of
committee,…). It also gives information on projects, replaced IEC publications issued since 2002. Some entries have been
and withdrawn publications. collected from earlier publications of IEC TC 37, 77, 86 and

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IEC 62359 ®
Edition 2.0 2017-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
A MENDMENT 1
AM ENDEMENT 1
Ultrasonics – Field characterization – Test methods for the determination of

thermal and mechanical indices related to medical diagnostic ultrasonic fields

Ultrasons – Caractérisation du champ – Méthodes d'essai pour la détermination

d'indices thermique et mécanique des champs d'ultrasons utilisés pour le

diagnostic médical
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 17.140.50 ISBN 978-2-8322-5301-4

– 2 – IEC 62359:2010/AMD1:2017
© IEC 2017
FOREWORD
This amendment has been prepared by IEC technical committee 87: Ultrasonics.
This bilingual version (2018-01) corresponds to the monolingual English version, published in
2017-09.
The text of this amendment is based on the following documents:
FDIS Report on voting
87/661/FDIS 87/665/RVD
Full information on the voting for the approval of this amendment can be found in the report
on voting indicated in the above table.
The French version of this amendment has not been voted upon.
The committee has decided that the contents of this amendment and the base publication will
remain unchanged until the stability date indicated on the IEC website under
"http://webstore.iec.ch" in the data related to the specific publication. At this date, the
publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
_____________
Introduction to Amendment
The second edition of IEC 62359 was published in 2010. Since then,
IEC 60601-2-37:2007/AMD1:2015 has been published and calls for provision of attenuated
spatial peak temporal average intensity, I , and attenuated spatial peak pulse
spta,a
, at specific spatial maximum points in the ultrasonic field on the
average intensity, I
sppa,a
beam axis. No IEC standard describes the determination of these quantities at these specific
positions. IEC 62359 for determining the thermal indices currently uses similar values at other
positions, therefore, the determination of attenuated spatial peak temporal average
intensity, I , and attenuated spatial peak pulse average intensity, I , has been
spta,a sppa,a
added as an annex in this amendment.
Additionally, references to newly published collateral standards have been updated.
_____________
© IEC 2017
2 Normative references
Replace the first reference by the following:
IEC 60601-2-37:2007, Medical electrical equipment – Part 2-37: Particular requirements for
the basic safety and essential performance of ultrasonic medical diagnostic and monitoring
equipment
IEC 60601-2-37:2007/AMD1:2015
Replace the second reference by the following:
IEC 61157:2007, Standard means for the reporting of the acoustic output of medical
diagnostic ultrasonic equipment
IEC 61157:2007/AMD1:2013
Replace, in the third reference, "IEC 61161:2006" by "IEC 61161:2013".
Replace the fifth reference by the following:
IEC 62127-1:2007, Ultrasonics – Hydrophones – Part 1: Measurement and characterization of
medical ultrasonic fields up to 40 MHz
IEC 62127-1:2007/AMD1:2013
3 Terms and definitions
Replace the first existing paragraph by the following new paragraph:
For the purposes of this document, the terms and definitions given in IEC 60601-2-37,
IEC 62127-1, IEC 62127-2, IEC 62127-3, IEC 61157 and IEC 61161 apply. Several of these
are repeated below for convenience and others are listed because they have been modified
for application to this standard.
3.3
acoustic repetition period
Replace the existing definition by the following new definition:
time interval between corresponding points of consecutive cycles, pulses or scans, depending
on the current operating mode
Add the following new NOTES 2 and 3:
NOTE 2 For continuous wave modes, the acoustic repetition period is the time interval between corresponding
points of consecutive cycles
NOTE 3 For combined operating modes where transmit pulsing of the constituent modes may be interrupted,
the arp determination should take into account non-pulsing time to calculate an average period.
Replace "NOTE 2" by NOTE 4".
3.4
acoustic working frequency
Replace, in the existing definition, the words "at the position corresponding to the spatial-
peak temporal-peak acoustic pressure" by "on the beam axis, beyond the break-point
depth, corresponding to depth of maximum pulse-intensity integral z "
pii
Replace, in existing NOTE 2, the words "at the position of maximum pulse-pressure-squared
integral" by "at the depth for peak pulse-intensity integral".

– 4 – IEC 62359:2010/AMD1:2017
© IEC 2017
3.7
attenuated peak-rarefactional acoustic pressure
Replace, in the existing definition, the words "at a specified distance from" by "on a plane
perpendicular to the beam axis at a specified distance z from".
Replace, in the definition list after Equation (2), the words "z is the distance from the external
transducer aperture to the point of interest" by "z is the distance from the external
transducer aperture along the beam axis to the plane containing the point of interest".
3.8
attenuated pulse-intensity integral
Replace, in the definition, the words "at a specified distance from" by "on a plane
perpendicular to the beam axis at a specified distance z from".
Replace, in the definition list after Equation (3), the words "z is the distance from the external
transducer aperture to the point of interest" by "z is the distance from the external
transducer aperture along the beam axis to the plane containing the point of interest".
Replace "NOTE" by "NOTE 1".
Add new NOTE 2:
NOTE 2 For measurement purposes of this standard, pii is equivalent to 1/(ρc) times the attenuated pulse-
α
pressure-squared integral at depth z, with ρc denoting the characteristic acoustic impedance of pure water.
3.9
attenuated spatial-average temporal-average intensity
Replace, in the definition, the words "at a specified distance from" by "on a plane
perpendicular to the beam axis at a specified distance z from".
Replace, in the definition list after Equation (4), the words "z is the distance from the external
transducer aperture to the point of interest" by "z is the distance from the external
transducer aperture along the beam axis to the plane containing the point of interest".
3.10
attenuated spatial-peak temporal-average intensity
Replace, in the definition, the words "at a specified distance from" by "on a plane
perpendicular to the beam axis at a specified distance z from".
Replace, in the definition list after Equation (5), the words "z is the distance from the external
transducer aperture to the point of interest" by "z is the distance from the external
transducer aperture along the beam axis to the plane containing the point of interest".
3.11
attenuated temporal-average intensity
Replace, in the definition, the words "at a specified distance from" by "on a plane
perpendicular to the beam axis at a specified distance z from".
Replace, in the definition list after Equation (6), the words "z is the distance from the external
is the distance from the external
transducer aperture to the point of interest" by "z
transducer aperture along the beam axis to the plane containing the point of interest".
3.13
beam-axis
Replace the term "beam-axis" by "beam axis".

© IEC 2017
3.17
bone thermal index
Delete, in the definition, "or neonatal cephalic (through the fontanelle)".
3.19
break-point depth
Add, after the existing definition, the words "acoustic working frequency and intensity
parameters (such as attenuated spatial-peak temporal-average intensity)"
Add, after "where D is the equivalent aperture diameter" the words "for non-scanning
eq
modes".
Replace the existing NOTE 2 by the following new note:
NOTE 2 For scanning modes, use the non-scanning mode D value calculation [Equation (8)]. Do this using
eq
the output beam area of one ultrasonic scan line; the central scan line, corresponding to the beam axis (i.e. the
line where pii MI, and f are measured).

,
awf
3.21
cranial-bone thermal index
Replace the existing definition by the following new definition:
thermal index fo
...