SIST EN ISO 14708-7:2022

SLOVENSKI STANDARD
01-oktober-2022
Vsadki (implantati) za kirurgijo - Aktivni medicinski pripomočki za vsaditev - 7. del:
Posebne zahteve za sisteme s polžkovim vsadkom (ISO 14708-7:2019, popravljena
verzija 2020-05)
Implants for surgery - Active implantable medical devices - Part 7: Particular
requirements for cochlear and auditory brainstem implant systems (ISO 14708-7:2019)
Chirurgische Implantate - Aktive implantierbare medizinische Geräte - Teil 7: Besondere
Anforderungen an Cochlea-Implantat Systeme (ISO 14708-7:2019)
Implants chirurgicaux - Dispositifs médicaux implantables actifs - Partie 7: Exigences
particulières pour les systèmes d'implant cochléaire (ISO 14708-7:2019)
Ta slovenski standard je istoveten z: EN ISO 14708-7:2022
ICS:
11.040.40 Implantanti za kirurgijo, Implants for surgery,
protetiko in ortetiko prosthetics and orthotics
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN ISO 14708-7

NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2022
ICS 11.040.40
English version
Implants for surgery - Active implantable medical devices -
Part 7: Particular requirements for cochlear and auditory
brainstem implant systems (ISO 14708-7:2019)
Implants chirurgicaux - Dispositifs médicaux Chirurgische Implantate - Aktive implantierbare
implantables actifs - Partie 7: Exigences particulières medizinische Geräte - Teil 7: Besondere
pour les systèmes d'implant cochléaire et d'implant Anforderungen an Cochlea-Implantat Systeme (ISO
auditif du tronc cérébral (ISO 14708-7:2019) 14708-7:2019)
This European Standard was approved by CEN on 6 July 2022.

CEN and 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 CEN and 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 CEN and CENELEC member into its own language and notified to the CEN-CENELEC
Management Centre has the same status as the official versions.

CEN and CENELEC members are the national standards bodies and national electrotechnical committees of Austria, Belgium,
Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,
Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia,
Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and United Kingdom.

CEN-CENELEC Management Centre:
Rue de la Science 23, B-1040 Brussels
© 2022 CEN/CENELEC All rights of exploitation in any form and by any means
Ref. No. EN ISO 14708-7:2022 E
reserved worldwide for CEN national Members and for
CENELEC Members.
Contents Page
European foreword . 3

European foreword
This document (EN ISO 14708-7:2022) has been prepared by Technical Committee ISO/TC 150
"Implants for surgery" in collaboration with Technical Committee CEN-CENELEC/ JTC 16 “Active
Implantable Medical Devices” the secretariat of which is held by DKE.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by January 2023, and conflicting national standards shall
be withdrawn at the latest by January 2023.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN-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 standards
body/national committee. A complete listing of these bodies can be found on the CEN and CENELEC
websites.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 14708-7:2019 has been approved by CEN-CENELEC as EN ISO 14708-7:2022 without
any modification.
INTERNATIONAL ISO
STANDARD 14708-7
Second edition
2019-12
Corrected version
2020-05
Implants for surgery — Active
implantable medical devices —
Part 7:
Particular requirements for cochlear
and auditory brainstem implant
systems
Implants chirurgicaux — Dispositifs médicaux implantables actifs —
Partie 7: Exigences particulières pour les systèmes d'implant
cochléaire et d'implant auditif du tronc cérébral
Reference number
ISO 14708-7:2019(E)
©
ISO 2019
ISO 14708-7:2019(E)
© ISO 2019
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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below or ISO’s member body in the country of the requester.
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Fax: +41 22 749 09 47
Email: copyright@iso.org
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Published in Switzerland
ii © ISO 2019 – All rights reserved

ISO 14708-7:2019(E)
Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Symbols and abbreviations . 3
5 General requirements for non-implantable parts . 3
5.1 General requirements for non-implantable parts . 3
5.2 General requirements for software . 3
5.3 Usability of non-implantable parts . 3
5.4 Data security and protection from harm caused by unauthorized information tampering 3
5.5 General requirements for risk management . 3
5.6 Misconnection of parts of the active implantable medical device . 3
5.7 Protection against external electrical hazards for fully implantable systems. 3
6 Inspection and measurement . 4
6.1 General . 4
6.2 Measurement of output signal characteristics . 4
6.3 Measurement of the output signal amplitude and pulse width . 4
6.4 Impedance measurement accuracy . 4
6.5 Inductive link characterization . 4
6.6 Sound processor battery testing . 4
7 General arrangement of the packaging . 4
8 General markings for active implantable medical devices . 4
9 Markings on the sales packaging . 4
10 Construction of the sales packaging . 5
11 Markings on the sterile pack. 5
12 Construction of the non-reusable pack . 5
13 Markings on the active implantable medical device . 5
14 Protection from unintentional biological effects being caused by the active
implantable medical device . 6
15 Protection from harm to the patient or user caused by external physical features of
the active implantable medical device . 6
16 Protection from harm to the patient caused by electricity . 6
17 Protection from harm to the patient caused by heat . 7
18 Protection from ionizing radiation released or emitted from the active implantable
medical device. 8
19 Protection from unintended effects caused by the device . 8
20 Protection of the device from damage caused by external defibrillators .9
21 Protection of the device from changes caused by high power electrical fields
applied directly to the patient . 9
22 Protection of the active implantable medical device from changes caused by
miscellaneous medical treatments .10
23 Protection of the active implantable medical device from mechanical forces .18
ISO 14708-7:2019(E)
24 Protection of the active implantable medical device from damage caused by
electrostatic discharge .22
25 Protection of the active implantable medical device from damage caused by
atmospheric pressure changes .22
26 Protection of the active implantable medical device from damage caused by
temperature changes .23
27 Protection of the active implantable medical device from electromagnetic non-
ionising radiation .23
27.1 Protection from static magnetic fields .23
27.2 Radiated magnetic field test for frequencies 16,6 Hz to 27 MHz .23
27.3 Radiated electric field test for frequencies 10 MHz to 2,7 GHz .25
27.4 General test configuration and setup .25
27.4.1 Test configuration and setup .25
27.4.2 Operating functions, modes and settings .26
27.4.3 Patient physiological simulation .26
27.5 Acceptance Criteria .26
28 Accompanying documentation .27
Annex A (informative) General guidance and rationale .31
Annex B (informative) Relationship between the fundamental principles in ISO/TR 14283
and the clauses of this document .42
Annex C (informative) Notes on EN 45502-2-3 (basis for this document) .61
Annex D (informative) Notes on EMI measurements to demonstrate compliance with Clause 27 .62
Bibliography .66
iv © ISO 2019 – All rights reserved

ISO 14708-7:2019(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).
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 150, Implants for surgery, Subcommittee
SC 6, Active implants.
This second edition cancels and replaces the first edition (ISO 14708-7:2013), which has been technically
revised. The main changes compared to the previous edition are as follows:
— alignment to the revised ISO 14708-1:2014;
— significant changes to Clauses 17, 22 and 27;
— many clauses have been replaced by references to ANSI/AAMI CI86: 2017.
A list of all part in the ISO 14708 series can be found on the ISO website.
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.
This corrected version of ISO 7063:2018 incorporates the following correction: in 16.2, the word
"direct" was added in the following sentence: "The maximum direct current density at the electrode
contact opening shall be no more than 0,75 μA/mm ".
ISO 14708-7:2019(E)
Introduction
This document specifies particular requirements for active implantable medical devices used to
treat hearing impairment via electrical stimulation (for example, cochlear implant systems or auditory
brainstem implant systems), to provide basic assurance of safety for both patients and users.
A cochlear implant system or auditory brainstem implant system is an active implantable medical device
comprising implantable and non-implantable parts (external parts). The power source can be externally
derived or from an internal battery. The implant system is designed to restore hearing via electrical
stimulation of the auditory pathways. Externally or internally processed acoustic information is
converted to electrical stimulation signals which are delivered via one or more electrodes. The working
parameters of the device may be adjusted via a non-implantable accessory.
This document is relevant to all parts of implant systems, including accessories.
The requirements of this document supplement or modify those of ISO 14708-1:2014.
In this document, terms printed in italic letters are used as defined in Clause 3. Where a defined term is
used as a qualifier in another term, it is not printed in italic letters unless the concept thus qualified is
also defined.
Information is also provided in Annex B that explains the relationship between ISO/TR 14283,
ISO 14708-1:2014 and this document.
Notes on EN 45502-2-3 (basis for this document) is provided in Annex C for information.
vi © ISO 2019 – All rights reserved

INTERNATIONAL STANDARD ISO 14708-7:2019(E)
Implants for surgery — Active implantable medical
devices —
Part 7:
Particular requirements for cochlear and auditory
brainstem implant systems
1 Scope
This document specifies requirements that are applicable to those active implantable medical devices
that are intended to treat hearing impairment via electrical stimulation of the auditory pathways.
Devices which treat hearing impairment via means other than electrical stimulation are not covered by
this document.
The tests that are specified in this document are type tests and are to be carried out on samples of a
device to show compliance.
This document is also applicable to non-implantable parts and accessories of the devices (see NOTE).
The electrical characteristics of the implantable part are determined by either the appropriate method
detailed in this document or by any other method demonstrated to have an accuracy equal to, or better
than, the method specified. In the case of dispute, the method detailed in this document applies.
NOTE A device that is commonly referred to as an active implantable medical device can in fact be a single
device, a combination of devices, or a combination of a device or devices and one or more accessories. Not all of
these parts are required to be either partially or totally implantable, this document specifies those requirements
of non-implantable parts and accessories which could affect the safety or performance of the implantable part.
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.
ISO/TS 10974, Assessment of the safety of magnetic resonance imaging for patients with an active
implantable medical device
ISO 14708-1:2014, Implants for surgery — Active implantable medical devices — Part 1: General
requirements for safety, marking and for information to be provided by the manufacturer
IEC 60068-2-31, Environmental testing — Part 2-31: Tests — Test Ec: Rough handling shocks, primarily for
equipment-type specimens
IEC 60601-1-2, Medical electrical equipment — Part 1-2: General requirements for basic safety and essential
performance — Collateral standard: Electromagnetic compatibility — Requirements and tests
IEC 61000-4-2, Electromagnetic compatibility (EMC) — Part 4-2: Testing and measurement techniques —
Electrostatic discharge immunity test
EN 1593, Non-destructive testing — Leak testing — Bubble emission techniques
EN 13185, Non-destructive testing — Leak testing — Tracer gas method
ISO 14708-7:2019(E)
ANSI/AAMI CI86: 2017, Cochlear implant systems: Requirements for safety, functional verification, labeling
and reliability reporting
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 14708-1:2014 and the
following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at http:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
cochlear implant system
CIS
active implantable medical device, comprising implantable and non-implantable parts (3.4), intended to
treat hearing impairment via electrical stimulation of the cochlea
3.2
auditory brainstem implant system
ABIS
active implantable medical device, comprising implantable and non-implantable parts (3.4), intended to
treat hearing impairment via electrical stimulation of the auditory brainstem
3.3
implant system
either cochlear implant system (3.1) or auditory brainstem implant system (3.2)
3.4
non-implantable part
external part of the implant system (3.3)
Note 1 to entry: Examples would include, but are not limited to, sound processor, microphone, coil or power source.
3.5
stimulator
implantable part of the implant system (3.3) containing electronic circuitry required to produce
electrical stimulation
3.6
body-worn
non-implantable part (3.4) of the implant system (3.3) and worn on the body (e.g. belt or ear level)
3.7
electrode contact
electrically conducting part which is designed to form an interface with body tissue or body fluid
3.8
electrode array
distal part of a lead containing more than one electrode contact (3.7)
3.9
reference electrode
electrically conducting part designed as return path for electrical stimulation current
3.10
model designation
name and/or a combination of letters and numbers used by a manufacturer to distinguish, by function
or type, one device from another
2 © ISO 2019 – All rights reserved

ISO 14708-7:2019(E)
3.11
serial number
unique combination of letters and/or numbers, selected by the manufacturer, intended to distinguish a
device from other devices with the same model designation (3.10)
3.12
output signal
electrical output, either pulsatile or analogue, of an implant system (3.3) intended to stimulate the
auditory pathways
3.13
use-before-date
date after which the manufacturer recommends that the implant system (3.3) should not be implanted
4 Symbols and abbreviations
There are no requirements specified in this document. However, this does not preclude the use of
symbols defined in other standards nor special symbols defined in the accompanying documentation.
5 General requirements for non-implantable parts
5.1 General requirements for non-implantable parts
The text in ISO 14708-1:2014, 5.1 applies.
5.2 General requirements for software
The text in ISO 14708-1:2014, 5.2 applies.
5.3 Usability of non-implantable parts
The text in ISO 14708-1:2014, 5.3 applies.
5.4 Data security and protection from harm caused by unauthorized information
tampering
The text in ISO 14708-1:2014, 5.4 applies.
5.5 General requirements for risk management
The text in ISO 14708-1:2014, 5.5 applies.
5.6 Misconnection of parts of the active implantable medical device
The text in ISO 14708-1:2014, 5.6 applies.
5.7 Protection against external electrical hazards for fully implantable systems
The text in ANSI/AAMI CI86: 2017, 5.7 applies.
ISO 14708-7:2019(E)
6 Inspection and measurement
6.1 General
If this document refers to inspection of design analysis documentation provided by the manufacturer, it
shall include an inspection of the risk management file as required by ISO 14971.
6.2 Measurement of output signal characteristics
The text in ANSI/AAMI CI86: 2017, 8.1 applies.
NOTE This ANSI/AAMI CI86 subclause is not a measurement step but describes the test configuration for
the measurement steps in 6.3 to 6.5.
6.3 Measurement of the output signal amplitude and pulse width
The text in ANSI/AAMI CI86: 2017, 8.2 applies.
6.4 Impedance measurement accuracy
The text in ANSI/AAMI CI86: 2017, 8.3 applies.
6.5 Inductive link characterization
The text in ANSI/AAMI CI86: 2017, 8.4 applies.
6.6 Sound processor battery testing
The text in ANSI/AAMI CI86: 2017, 8.5 applies.
7 General arrangement of the packaging
The text in ISO 14708-1:2014, Clause 7 applies.
8 General markings for active implantable medical devices
The text in ISO 14708-1:2014, Clause 8 applies.
9 Markings on the sales packaging
9.1 The text in ISO 14708-1:2014, 9.1 applies.
9.2 The sales packaging shall bear the name and full address of the manufacturer.
The sales packaging shall also bear the name and address of the authorized representative, if the
manufacturer does not have a registered place of business in the European Community.
Compliance is checked by inspection.
9.3 Where an implant system is supplied in separate sub-assembly packaging, each individual sales
packaging shall bear a description of the contents of the packaging, the model designation or part number
and, if applicable the batch number or the serial number.
Compliance is checked by inspection.
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ISO 14708-7:2019(E)
9.4 The text in ISO 14708-1:2014, 9.4 applies.
9.5 The text in ISO 14708-1:2014, 9.5 applies.
9.6 The text in ISO 14708-1:2014, 9.6 applies.
9.7 The text in ISO 14708-1:2014, 9.7 applies.
10 Construction of the sales packaging
10.1 The text in ISO 14708-1:2014, 10.1 applies.
10.2 The text in ISO 14708-1:2014, 10.2 applies.
10.3 The text in ISO 14708-1:2014, 10.3 applies.
NOTE Removable stickers, which provide supplementary information exceeding the information specified
in Clause 9, need not be subjected to the test specified in 10.3.
11 Markings on the sterile pack
11.1 The text in ISO 14708-1:2014, 11.1 applies.
11.2 The text in ISO 14708-1:2014, 11.2 applies.
12 Construction of the non-reusable pack
12.1 The text in ISO 14708-1:2014, 12.1 applies.
12.2 The text in ISO 14708-1:2014, 12.2 applies.
12.3 The text in ISO 14708-1:2014, 12.3 applies.
13 Markings on the active implantable medical device
13.1 The text in ISO 14708-1:2014, 13.1 applies.
13.2 The text in ISO 14708-1:2014, 13.2 applies.
13.3 Implantable parts of an implant system shall be unequivocally identifiable (particularly with regard
to the model designation of the device), when necessary, without the need for a surgical intervention.
Compliance shall be confirmed by inspection of the procedure defined by the manufacturer in the
instructions for use (see 28.6).
NOTE Annex A provides additional context for this and other subclauses.
13.4 The text in ISO 14708-1:2014, 13.4 applies.
ISO 14708-7:2019(E)
14 Protection from unintentional biological effects being caused by the active
implantable medical device
14.1 The text in ISO 14708-1:2014, 14.1 applies.
14.2 Any implantable part of the active implantable medical device, intended in normal use to be in
contact with body fluids, shall cause no unacceptable release of particulate matter when the device is
used as intended by the manufacturer.
Test: The implantable part of the implant system shall be removed aseptically from the non-reusable
pack. The implantable part shall be immersed in a bath of saline solution, approximately 9 g/l and
suitable for injection in a neutral glass container. The volume of the saline in millilitres (ml) shall be
5 ± 0,5 times the numerical value of the surface area of the implantable part expressed in cm . The
container shall be covered with a glass lid and maintained at 37 ± 2 °C for between 8 h and 18 h, the
bath being agitated throughout the period. A reference sample of similar volume shall be prepared
from the same batch of saline, maintained and agitated in a similar way to the specimen. A sample of
liquid from the specimen bath and from the reference bath shall be compared using apparatus suitable
for measurement of particle size, such as apparatus operating on the light blockage principle (see
method V.5.7.1 of the European Pharmacopoeia) or the electrical zone sensing principle (the Coulter
principle, see Appendix XIII of the British Pharmacopoeia).
Compliance shall be confirmed if the excess average count of unintentional particles from the specimen
compared to the reference sample does not exceed 100 per ml greater than 5,0 µm and does not exceed
5 per ml greater than 25 µm.
14.3 The text in ISO 14708-1:2014, 14.3 applies.
14.4 The text in ISO 14708-1:2014, 14.4 applies.
15 Protection from harm to the patient or user caused by external physical
features of the active implantable medical device
15.1 The text in ISO 14708-1:2014, 15.1 applies.
15.2 The text in ANSI/AAMI CI86:2017, 6.4 applies.
16 Protection from harm to the patient caused by electricity
16.1 The text in ANSI/AAMI CI86:2017, 17.1 applies.
16.2 Except for its intended function, a cochlear implant system pulse generator, when in use, shall be
electrically neutral.
The maximum direct current density at the electrode contact opening shall be no more than 0,75 μA/mm .
In addition, the net direct current shall not exceed 0,1 μA.
NOTE The electrode contact opening is the area exposed to tissue and is not covered by insulation. In the
case of recessed electrodes, the electrode contact opening is the opening in the outer surface of the insulating
part of the electrode that might expose the tissue to the electric current.
16.3 The text in ISO 14708-1:2014, 16.3 applies.
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ISO 14708-7:2019(E)
16.4 Charge and charge density limits for biphasic, charge-balanced pulses
The text in ANSI/AAMI CI86: 2017, 17.3 applies.
16.5 Phase duration requirements
The text in ANSI/AAMI CI86: 2017, 17.4 applies.
16.6 Stimulation waveform requirements
The text in ANSI/AAMI CI86: 2017, 17.5 applies.
17 Protection from harm to the patient caused by heat
17.1 In the absence of external influence, an implantable part of the implant system, not intended to
supply heat to the patient, shall be in accordance with at least one of the following conditions [a), b) or
c)] when implanted, and whether in normal operation, including recharge:
NOTE Examples of external influences include exposure to MRI, electrosurgery, external defibrillation,
ultrasound and electromagnetic fields.
a) no outer surface greater than 39 °C,
b) no tissue receives a thermal dose greater than the CEM43 dose thresholds in Table 1, or
c) manufacturer’s evidence that a transient higher temperature rise is justified for a particular
application based upon an analysis of the risk.
Because the values in Table 1 represent tissue dose thresholds, the manufacturer’s risk assessment
shall include an analysis of any effects to the patient due to the time/temperature relationship.
Table 1 — CEM43 dose thresholds for various tissues
Tissue CEM43 dose threshold
muscle 40
fat 40
peripheral nerve 40
skin 21
bone 16
brain 2
BBB (blood brain barrier) 15
The CEM43 value is calculated using the following formula:
n
43−T
()
i
CEM43≅⋅tR
i
∑
i=1
where
t is the i-th time interval in minutes;
i
T is the average temperature of the tissue in degrees Celsius during the interval t ;
i i
R is 0,25 for T < 43 °C and 0,5 for T ≥ 43 °C;
n is the number of samples taken during the heating duration.
ISO 14708-7:2019(E)
NOTE 1 The above CEM43 formula is an approximation of the integral form.
This formula is valid for temperatures between 39 °C and 57 °C.
Compliance is checked by inspection of a design analysis provided by the manufacturer, supported by
the manufacturer’s calculations and data from test studies as appropriate.
NOTE 2 For the purpose of design verification, a body temperature of 37 °C can be assumed.
NOTE 3 A future edition of this document might include examples of acceptable calculations, analyses and/or
test methods.
17.2 The text in ISO 14708-1:2014, 17.2 does not apply.
18 Protection from ionizing radiation released or emitted from the active
implantable medical device
18.1 The text in ISO 14708-1:2014, 18.1 applies.
18.2 The text in ISO 14708-1:2014, 18.2 applies.
18.3 The text in ISO 14708-1:2014, 18.3 applies.
19 Protection from unintended effects caused by the device
NOTE See also 28.20.
19.1 The text in ISO 14708-1:2014, 19.1 applies.
19.2 The text in ISO 14708-1:2014, 19.2 applies.
19.3 The text in ISO 14708-1:2014, 19.3 applies.
19.4 The text in ISO 14708-1:2014, 19.4 applies.
19.5 The text in ISO 14708-1:2014, 19.5 applies.
19.6 The text in ISO 14708-1:2014, 19.6 applies.
19.7 The physical, biological and geometric properties of the implantable parts of an implant system
shall, as far as necessary, be designed to ensure that device removal and replacement with a device from
the same manufacturer is not compromised.
Compliance shall be confirmed by inspection of a design analysis provided by the manufacturer and
where available supported by appropriate test and clinical data, for example, post market surveillance
data relating to device replacement.
19.8 The implantable stimulator case of an implant system intended in normal use to be in contact with
body fluids shall provide sufficient hermeticity so that no fluid can infiltrate the stimulator case.
Tests: Fine and gross leak tests shall be conducted on the hermetic casing of the stimulator of an implant
system in accordance with EN 13185 and EN 1593. Alternatively, testing may be conducted as specified
8 © ISO 2019 – All rights reserved

ISO 14708-7:2019(E)
in MIL STD 883 Method 1014. If a group A technique is used from EN 13185 then a gross leak test is not
required; if a group B technique is used then the gross leak test shall follow the fine leak test.
NOTE The manufacturer can include adequate hermeticity testing in their manufacturing process.
Compliance shall be confirmed by inspection of test procedures and results provided by the
−9 3
manufacturer and by the device leak rate not exceeding 5 × 10 Pa m /s for the fine leak test and
no definite stream of bubbles, or two or more large bubbles, originating from the same point of the
stimulator case for the gross leak test.
19.9 Implantable device internal moisture content
The text in ANSI/AAMI CI86: 2017, 20.7 applies.
20 Protection of the device from damage caused by external defibrillators
NOTE See also 28.12.
20.1 The text in ISO 14708-1:2014, 20.1 is not applicable to this document.
20.2 The text in ISO 14708-1:2014, 20.2 applies.
21 Protection of the device from changes caused by high power electrical fields
applied directly to the patient
NOTE See also 28.12 and 28.13.
21.1 The implantable part of an implant system shall be designed so that stray, high frequency current
from surgical equipment (surgical diathermy) flowing through the patient shall not permanently affect
the device provided the implant system does not lie directly in the path between cutting and return [radio
frequency (RF) earth] electrodes (see also requirement for warning advice, 28.13).
Test: Use a signal generator with an output impedance of 50 Ω (R1). The test signal frequency shall be
500 kHz sinusoid and the open loop test signal amplitude 20 V .
pp
The implant system shall be switched off. Each output of the implantable part of the implant system shall
be connected via a resistor (R) of 4,7 kΩ to a common point which shall be connected to the output of
the signal generator (see Figure 1). The reference electrode of the implantable part of the implant system
shall be connected via a 100 Ω resistor (R3) to the ground of the signal generator.
ISO 14708-7:2019(E)
a
Cochlear or brainstem implant.
Figure 1 — Test set-up for proof of protection from high frequency currents caused by surgical
equipment
Apply the test signal in 10 bursts each for a duration of 1 s, allowing a recovery period of 5 s
between bursts.
Compliance shall be confirmed if, after completing the test procedure and reactivating, the implant
system characteristics conform with the manufacturer’s original specification.
21.2 The text in ISO 14708-1:2014, 21.2 applies.
22 Protection of the active implantable medical device from changes caused by
miscellaneous medical treatments
NOTE See also 28.12, 28.14 and 28.15.
22.1 The text in ISO 14708-1:2014, 22.1 applies.
22.2 The text in ISO 14708-1:2014, 22.2 applies.
22.2.1 All parts of an implant system shall be assessed for safety in the MR environment (see 28.8) and
labelled as either MR Unsafe or MR Conditional as required in 28.12.
The manufacturer shall declare (see 28.12) the conditions (including the specific field strengths) under
which the safety of MRI testing has been verified.
The declaration shall include the risk for demagnetisation, image distortion and instructions for safe
performance of MRI examinations, where applicable.
10 © ISO 2019 – All rights reserved

ISO 14708-7:2019(E)
The risks to a subject implanted with an implant system entering an MRI machine can be grouped under
the following areas:
1) magnetically induced torque;
2) magnetically induced displacement force;
3) gradient-induced vibration;
4) radio frequency induced heating;
5) gradient-induced heating;
6) unintentional device output;
7) implant magnet weakening;
8) loss of implant functionality;
9) imaging artefact;
10) magnet dislocation.
Each of these factors shall be tested in accordance with 22.2.2 to 22.2.11.
22.2.2 Magnetically induced torque: Torque is exerted on the implant magnet, aiming to align the
magnet so that its magnetization is parallel to the static magnetic field B .
Test method: Measure the B -induced torque acting on the implantable parts of an implant system
according to the method described in ASTM F2213 or an equivalent method.
Acceptance criteria: Magnetically induced (B -induced) torque shall be less than the worst-case
gravity-induced torque which is defined as the product of the weight of the device and the longest linear
dimension or less than a greater specified value supported by a scientific based rationale.
The implantable part of an implant system shall not produce any unacceptable risk to the patient arising
from mechanical loads that can occur during MRI scanning. A rationale shall be given as to why the
induced torque during MRI does not produce unacceptable risk.
22.2.3 Magnetically induced displacement force: A magnetically induced displacement force acts to
pull ferromagnetic and paramagnetic elements of the implant into the bore of the MRI system.
Test method: Magnetically induced forces acting on the implant shall be measured according to the
method described in ASTM F2052 or any equivalent method.
Acceptance criteria: Magnetically induced force shall be less than the weight of the device or less than
a greater speci
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