EN 50527-2-1:2016
(Main)Procedure for the assessment of the exposure to electromagnetic fields of workers bearing active implantable medical devices - Part 2-1: Specific assessment for workers with cardiac pacemakers
Procedure for the assessment of the exposure to electromagnetic fields of workers bearing active implantable medical devices - Part 2-1: Specific assessment for workers with cardiac pacemakers
This European Standard provides the procedure for the specific assessment required in EN 50527-1:2016, Annex A, for workers with implanted pacemakers. It offers different approaches for doing the risk assessment. The most suitable one will be used. If the worker has other Active Implantable Medical Devices (AIMDs) implanted additionally, they need to be assessed separately. The purpose of the specific assessment is to determine the risk for workers with implanted pacemakers arising from exposure to electromagnetic fields at the workplace. The assessment includes the likelihood of clinically significant effects and takes account of both transient and long-term exposure within specific areas of the workplace. NOTE 1 This standard does not address risks from contact currents. The techniques described in the different approaches may also be used for the assessment of publicly accessible areas. The frequency range to be observed is from 0 Hz to 3 GHz. Above 3 GHz no interference with the pacemaker occurs when the exposure limits are not exceeded. NOTE 2 The rationale for limiting the observation range to 3 GHz can be found in ISO 14117:2012, Clause 5.
Verfahren zur Beurteilung der Exposition von Arbeitnehmern mit aktiven implantierbaren medizinischen Geräten (AIMD) gegenüber elektromagnetischen Feldern - Teil 2-1: Besondere Beurteilung für Arbeitnehmer mit Herzschrittmachern
Procédure pour l’évaluation de l’exposition des travailleurs porteurs de dispositifs médicaux implantables actifs aux champs électromagnétiques - Partie 2-1: Spécification d’évaluation pour les travailleurs avec un simulateur cardiaque
La présente Norme européenne fournit la procédure d'évaluation spécifique exigée dans l’Annexe A de l'EN 50527 1:2016, pour les travailleurs porteurs de stimulateurs cardiaques implantés. Elle propose différentes approches pour réaliser l’appréciation du risque. Celle qui convient le mieux est utilisée. Si le travailleur a en plus d’autres dispositifs médicaux implantables actifs implantés, il est nécessaire de les évaluer individuellement. Le but de cette évaluation spécifique est de déterminer pour des travailleurs porteurs de stimulateurs cardiaques implantés le risque provenant de l'exposition aux champs électromagnétiques sur le lieu de travail. L'évaluation comprend la probabilité d'effets cliniquement significatifs et tient compte à la fois de l'exposition transitoire et de l’exposition de longue durée dans des zones spécifiques du lieu de travail. NOTE 1 La présente norme ne concerne pas les risques vis-à-vis des courants de contact. Les techniques décrites dans les différentes approches peuvent aussi être utilisées pour l’évaluation des zones accessibles au public. La plage de fréquences à observer comprend les fréquences entre 0 Hz et 3 GHz. Au-dessus de 3 GHz, aucune interférence ne se produit avec le stimulateur cardiaque lorsque les limites d'exposition ne sont pas dépassées. NOTE 2 La justification de la limitation de la plage d'observation à 3 GHz peut être consultée à l'Article 5 de l'ISO 14117:2012.
Postopek ocenjevanja izpostavljenosti delavcev z aktivnimi medicinskimi vsadki elektromagnetnim poljem - 2-1. del: Specifično ocenjevanje delavcev s srčnimi spodbujevalniki
Ta evropski standard določa postopek za specifično ocenjevanje v skladu s standardom EN 50527-1:2016, dodatek A, za delavce z vsajenimi srčnimi spodbujevalniki. Ponuja različne pristope za izvedbo ocenjevanja tveganja, uporabiti pa je treba najprimernejšega. Če delavec dodatno uporablja druge aktivne medicinske vsadke, mora biti ocenjen ločeno.
Namen specifičnega ocenjevanja je določiti tveganje za delavce z vsajenimi srčnimi spodbujevalniki zaradi izpostavljenosti elektromagnetnim poljem na delovnem mestu. Ocena vključuje verjetnost klinično pomembnih vplivov in upošteva tako prehodno kot dolgotrajno izpostavljenost v določenih območjih delovnega mesta.
OPOMBA 1: Ta standard ne obravnava tveganj zaradi kontaktnih tokov.
Tehnike, opisane v okviru različnih pristopov, se lahko uporabijo tudi za ocenjevanje javno
dostopnih območij.
Upoštevani frekvenčni razpon je od 0 Hz do 3 GHz. Nad vrednostjo 3 GHz ne pride do motenj delovanja srčnega spodbujevalnika, če mejne vrednosti za izpostavljenost niso presežene.
OPOMBA 2: Utemeljitev za omejevanje razpona na 3 GHz lahko najdete v standardu ISO 14117:2012, točka 5.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
01-april-2017
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SIST EN 50527-2-1:2011
3RVWRSHNRFHQMHYDQMDL]SRVWDYOMHQRVWLGHODYFHY]DNWLYQLPLPHGLFLQVNLPLYVDGNL
HOHNWURPDJQHWQLPSROMHPGHO 6SHFLILþQRRFHQMHYDQMHGHODYFHYVVUþQLPL
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Procedure for the assessment of the exposure to electromagnetic fields of workers
bearing active implantable medical devices - Part 2-1: Specific assessment for workers
with cardiac pacemakers
Verfahren zur Beurteilung der Exposition von Arbeitnehmern mit aktiven implantierbaren
medizinischen Geräten (AIMD) gegenüber elektromagnetischen Feldern - Teil 2-1:
Besondere Beurteilung für Arbeitnehmer mit Herzschrittmachern
Procédure pour l’évaluation de l’exposition des travailleurs porteurs de dispositifs
médicaux implantables actifs aux champs électromagnétiques - Partie 2-1: Spécification
d’évaluation pour les travailleurs avec un simulateur cardiaque
Ta slovenski standard je istoveten z: EN 50527-2-1:2016
ICS:
11.040.40 Implantanti za kirurgijo, Implants for surgery,
protetiko in ortetiko prosthetics and orthotics
13.100 Varnost pri delu. Industrijska Occupational safety.
higiena Industrial hygiene
17.240 Merjenje sevanja Radiation measurements
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EUROPEAN STANDARD EN 50527-2-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
December 2016
ICS 11.040.40; 17.240 Supersedes EN 50527-2-1:2011
English Version
Procedure for the assessment of the exposure to
electromagnetic fields of workers bearing active implantable
medical devices - Part 2-1: Specific assessment for workers with
cardiac pacemakers
Procédure pour l'évaluation de l'exposition des travailleurs Verfahren zur Beurteilung der Exposition von
porteurs de dispositifs médicaux implantables actifs aux Arbeitnehmern mit aktiven implantierbaren medizinischen
champs électromagnétiques - Partie 2-1: Spécification Geräten (AIMD) gegenüber elektromagnetischen Feldern -
d'évaluation pour les travailleurs avec un simulateur Teil 2-1: Besondere Beurteilung für Arbeitnehmer mit
cardiaque Herzschrittmachern
This European Standard was approved by CENELEC on 2016-07-04. 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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2016 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN 50527-2-1:2016 E
Contents Page
European foreword . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Specific assessment . 8
4.1 Description of the assessment process . 8
4.1.1 General . 8
4.1.2 Equipment consideration . 11
4.1.3 Patient warning consideration . 11
4.1.4 Cases for additional investigation . 11
4.1.5 Choice of investigative method . 14
4.2 Clinical investigation . 15
4.3 Non-clinical investigation . 15
4.3.1 General . 15
4.3.2 Non-clinical investigation by in vitro testing . 16
4.3.3 Non-clinical investigation by comparative study . 17
5 Documentation . 20
Annex A (normative) Pacemaker specific replacement of EN 50527-1:2016, Table 1 . 21
Annex B (informative) Clinical investigation methods . 27
B.1 External ECG monitoring . 27
B.2 Assessment of pacemaker compatibility using stored data and diagnostic features . 27
B.3 Real time event monitoring by telemetry . 27
Annex C (informative) in vitro testing/measurements . 29
C.1 Introduction . 29
C.2 EM phantom . 29
C.2.1 General . 29
C.2.2 EM phantom design . 29
C.3 Basic procedure for cardiac pacemaker in vitro testing . 30
C.4 References . 31
C.5 Literature . 32
Annex D (informative) Modelling . 33
D.1 General . 33
D.2 Analytical techniques . 33
D.3 Numerical techniques . 33
D.4 Field modelling or calculations . 33
D.5 Modelling the human body and implant . 34
D.6 References . 34
Annex E (informative) Derived worst case conversions for frequencies below 450 MHz . 35
E.1 Introduction . 35
E.2 Functionality of implanted pacemaker leads . 35
E.3 Conversion based on known field strength. 36
E.3.1 General . 36
E.3.2 Low frequency range (below 5 MHz) . 36
E.3.3 Pure magnetic field (16 Hz to 5 MHz) . 37
E.3.4 Pure electric field (16 Hz to 150 kHz) . 39
E.3.5 Field with electric component (16 Hz to 150 kHz) . 42
E.3.6 Field with electric and magnetic component (150 kHz to 5 MHz) . 43
E.3.7 Range between low and high frequency ranges (5 MHz to 30 MHz) . 44
E.3.8 High frequency range (above 30 MHz) . 44
E.4 Conversion based on known compliance with basic restrictions. 46
E.4.1 General . 46
E.4.2 Short survey on the direct effects of human exposure (induced current density) . 46
E.4.3 Short survey on induced voltages on an implanted lead . 48
E.4.4 A simple model to analyse the possible voltages at pacemaker terminations
generated from induced current density equivalent the basic restrictions of Council
Recommendation 1999/519/EC . 48
E.5 References . 50
Annex F (informative) Interference from power-frequency magnetic and electric fields from
transmission, distribution and use of electricity . 52
F.1 Sensitivity of pacemakers to interference . 52
F.2 Immunity requirements . 52
F.3 Voltage induced in the leads by magnetic fields . 53
F.4 Voltage induced in the leads by electric fields . 54
F.5 Values of 50 Hz magnetic and electric field that may cause interference . 56
F.6 Factors that affect the immunity from interference . 57
F.6.1 Reasons for improved immunity . 57
F.6.2 Adjustment for pacemaker sensitivity . 58
F.7 Application to exposure situations . 59
F.7.1 Public exposures . 59
F.7.2 Beneath high voltage power lines . 59
F.7.3 Occupational settings. 60
F.7.4 Temporary exposure above the interference levels . 61
F.8 References . 61
Annex G (informative) Determination of the pacemaker immunity and guidelines provided by
pacemaker manufacturers – Determination method . 62
G.1 Introduction . 62
G.2 EMC and pacemakers – General guidelines . 62
G.3 Induced voltages, fields and zones . 65
G.3.1 Induced voltage test levels . 65
G.3.2 Magnetic field amplitudes producing test limits . 65
G.3.3 Induced voltage zones . 67
G.3.4 Magnetic field zones . 67
G.4 References . 68
G.5 Literature . 69
Bibliography . 70
Figures
Figure 1 — Overview of the assessment process . 9
Figure 2 — Pacemaker specific assessment process . 10
Figure 3 — Additional investigation process . 13
Figure 4 — Comparison process . 18
Figure C.1 — Example of in vitro procedure for EM interference at low frequency using planar
electrodes, bipolar lead and ECG and data recording . 31
Figure E.1 — Typical implantations of cardiac pacemakers (abdominal implantation with
prolonged lead is used in clinical environment only) . 36
Figure E.2 — Effective induction area of an open wire loop inside a conductive medium . 37
Figure E.3 — Schematic representation of bipolar pickup of interference in an infinitely extended
homogeneous conducting medium . 39
Figure E.4 — Induced voltage on the implanted lead in a pure E field . 41
Figure E.5 — Schematic graphs of the same voltage on the lead for different layouts . 43
Figure E.6 — Eddy-current inside a conductive medium induced by varying magnetic flux . 47
Figure E.7 — Voltage induced on a lead inside conductive body tissue . 48
Figure E.8 — Voltages on an implanted lead . 50
Figure F.1 — How the immunity ratio affects magnetic field that may result in interference . 58
Figure F.2 — How the immunity ratio affects electric field that may result in interference . 59
Figure G.1 — Induced voltage test levels . 65
Figure G.2 — Magnetic field amplitudes, for frequencies below 5 000 kHz, producing test limits in
unipolar configurations . 66
Figure G.3 — Induced voltage zones for unipolar configurations . 67
Figure G.4 — Magnetic field zones, for frequencies below 5 000 kHz and for unipolar
configurations . 68
Tables
Table A.1 — Compliant workplaces and equipment with exceptions . 21
Table F.1 — Amplitude of the immunity test signal applied . 53
Table F.2 — Values of 50 Hz electric and magnetic field (r.m.s.) that might, under unfavourable
circumstances, cause interference in a pacemaker . 56
Table F.3 — Summary of typical maximum field values beneath high-voltage overhead lines at
1 m above ground . 60
European foreword
This document (EN 50527-2-1:2016) has been prepared by CLC/TC 106X “Electromagnetic fields in the
human environment”.
The following dates are fixed:
• latest date by which this document has to be implemented (dop) 2017-07-04
at national level by publication of an identical national
standard or by endorsement
• latest date by which the national standards conflicting with (dow) 2019-07-04
this document have to be withdrawn
This document supersedes EN 50527-2-1:2011.
This document has been prepared under a mandate given to CENELEC by the European Commission and
the European Free Trade Association, and supports essential requirements of EU Directive(s).
EN 50527 is currently composed with the following parts:
— EN 50527-1, Procedure for the assessment of the exposure to electromagnetic fields of workers bearing
active implantable medical devices — Part 1: General;
— EN 50527-2-1, Procedure for the assessment of the exposure to electromagnetic fields of workers
bearing active implantable medical devices — Part 2-1: Specific assessment for workers with cardiac
pacemakers;
— prEN 50527-2-2, Procedure for the assessment of the exposure to electromagnetic fields of workers
bearing active implantable medical devices — Part 2-2: Specific assessment for workers with
1)
implantable cardioverter defibrillators .
———————
1) Currently at drafting stage.
1 Scope
This European Standard provides the procedure for the specific assessment required in EN 50527-1:2016,
Annex A, for workers with implanted pacemakers. It offers different approaches for doing the risk
assessment. The most suitable one will be used. If the worker has other Active Implantable Medical Devices
(AIMDs) implanted additionally, they need to be assessed separately.
The purpose of the specific assessment is to determine the risk for workers with implanted pacemakers
arising from exposure to electromagnetic fields at the workplace. The assessment includes the likelihood of
clinically significant effects and takes account of both transient and long-term exposure within specific areas
of the workplace.
NOTE 1 This standard does not address risks from contact currents.
The techniques described in the different approaches may also be used for the assessment of publicly
accessible areas.
The frequency range to be observed is from 0 Hz to 3 GHz. Above 3 GHz no interference with the
pacemaker occurs when the exposure limits are not exceeded.
NOTE 2 The rationale for limiting the observation range to 3 GHz can be found in ISO 14117:2012, Clause 5.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
2)
EN 45502-2-1:2003 , Active implantable medical devices — Part 2-1: Particular requirements for active
implantable medical devices intended to treat bradyarrhythmia (cardiac pacemakers)
EN 50413, Basic standard on measurement and calculation procedures for human exposure to electric,
magnetic and electromagnetic fields (0 Hz - 300 GHz)
EN 50527-1:2016, Procedure for the assessment of the exposure to electromagnetic fields of workers
bearing active implantable medical devices — Part 1: General
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 50527-1:2016 and the following
apply.
3.1
implantable pulse generator
IPG
part of the active implantable medical device, including the power supply and electronic circuit, that produces
an electrical output
Note 1 to entry: For the purposes of EN 50527–2–1, the term implantable pulse generator describes any active
implantable medical device that incorporates functions intended to treat cardiac arrhythmias.
3.2
pacemaker
active implantable medical device intended to treat bradyarrhythmias, comprising an implantable pulse
generator with or without lead(s)
———————
2) The EMC requirements within EN 45502–2-1 have been incorporated with updates into ISO 14117 and their use is recommended
here.
Note 1 to entry: CRT-P devices (Cardiac resynchronization therapy pacemaker) by their nature behave similar and are
covered by this standard. CRT-P devices are sometimes also called multi-channel pacemakers.
3.3
electrode
electrically conducting part (usually the termination of a lead) which is designed to form an interface with
body tissue or body fluid
3.4
unipolar lead
lead with one electrode
3.5
bipolar lead
lead with two electrodes that are electrically isolated from each other
3.6
pacemaker-employee
worker with an implanted pacemaker
Note 1 to entry: For this worker, EN 50527–1 has revealed that a specific assessment following EN 50527–1:2016,
Annex A needs to be done. If this worker bears additionally other AIMD, they need to be assessed separately.
3.7
assessment team
team consisting of:
— employer and if applicable, his occupational health and safety experts and/or occupational physician,
— pacemaker-Employee and his responsible physician,
— (technical and medical) experts as necessary, e.g. manufacturer of the pacemaker
3.8
Holter monitor
Holter ECG monitor
device that continuously records the heart's rhythms
Note 1 to entry: The monitor is usually worn for 24 h – 48 h during normal activity.
Note 2 to entry: The above definition was adopted from NIH (US. National Institute of Health). The Holter monitor is
named for Dr. Norman J. Holter, who invented telemetric cardiac monitoring in 1949. Clinical use started in the early
1960s. Numerous medical publications can be found referring to “Holter”, “Holter monitoring” or often also called “Holter
ECG monitoring” (see e.g. PubMed at http://www.ncbi.nlm.nih.gov/pubmed).
3.9
EM phantom
physical model containing tissue-equivalent material used to simulate the body in an experimental dose
measurement (from World Health Organization)
Note 1 to entry: EM phantoms are sometimes also referred to as torso simulator or phantom.
3.10
uninfluenced behaviour
behaviour for which conditions are provided in EN 50527-1:2016, 4.1.3
4 Specific assessment
4.1 Description of the assessment process
4.1.1 General
The risk assessment is based on the approach that, according to EN 45502-2-1 and ISO 14117, pacemakers
are expected to work uninfluenced as long as the General Public Reference levels of
Council Recommendation 1999/519/EC are not exceeded (except for static magnetic fields and for pulsed
high frequency electromagnetic fields) (see also F.7).
Further risk assessment is not necessary if a history of uninfluenced behaviour at the workplace exists and a
responsible physician has confirmed that this history is sufficient to exclude severe (clinically significant)
interaction.
A specific risk assessment for the pacemaker-Employee is required when there is history of influenced
behaviour or one of the following three conditions is fulfilled:
a) there is equipment present in the workplace that is neither included in, nor used in accordance with
Table A.1;
b) all equipment at the workplace is listed in Table A.1 (see Annex A) and is used accordingly, but the
pacemaker-Employee has received warning(s) from the responsible physician that the pacemaker may
be susceptible to electromagnetic interference (EMI), thereby increasing the risk at the workplace. There
are two types of warnings that may be given:
1) patient specific warnings provided by the responsible physician to the pacemaker-Employee due to
sensitivity settings in effect that may cause changes in pacemaker behaviour in the presence of
electromagnetic fields (EMF) that are below the reference levels; or
2) general warnings supplied by the pacemaker manufacturer in accompanying documentation about
recognized behaviour changes of the pacemaker when it is subjected to EMF generated by specific
types of equipment;
c) there is equipment present in the workplace that is neither included in, nor used in accordance with
Table A.1 and for which the pacemaker-Employee does have a history of uninfluenced behaviour while
in its presence, but the pacemaker-Employee has received a specific warning as described above.
In order to minimize the burden placed on the employer and pacemaker-Employee, the assessment should
begin with the investigation steps shown in Figure 1. The steps to be taken are based upon whether the
specific assessment is the result of an equipment issue or a patient warning issue.
When only condition (a) exists, then 4.1.2 shall apply. When only condition (b) exists, then 4.1.3 shall apply.
When condition (c) exists, then both 4.1.2 and 4.1.3 shall apply.
When a pacemaker is tested according to EN 45502–2-1, the manufacturer is required to provide a warning
to the implanting physician in the accompanying technical information as to any sensitivity settings available
in the device that if used, afford the device with a reduced immunity to certain types of EMI. A specific
warning would only be given to the patient receiving the implant if they were discharged with one of these
settings in effect, or if at follow-up, a change to one of these settings was made for clinical reasons.
For equipment included in and used per Table A.1
Legend
History
Un-
Influenced No History
influenced Further risk assessment is
Behaviour available
Behaviour not necessary
Yes
2 3 2
Warning
Specific risk assessment for
from
the pacemaker-Employee is
responsible
required
Physician
No
2 1 1
Further risk assessment
unnecessary if responsible
physician has confirmed
For Equipment not included in or not used per Table A.1
that this history is sufficient
to exclude clinically
Specific risk assessment for the pacemaker-Employee is
significant interaction
required
Figure 1 — Overview of the assessment process
Figure 2 — Pacemaker specific assessment process
4.1.2 Equipment consideration
Information relevant to the equipment or other field generating sources under consideration shall be
collected to answer sufficiently the following two questions:
• can it be determined that clinically significant interference with the pacemaker will not occur as a result
of expected exposure to the equipment under consideration? If so, no further assessment is required
and documentation of the result can proceed, as required in Clause 5;
• can it be determined that the pacemaker-Employee can return to the workplace only with restrictions
placed on the work tasks or areas of access? If so, no further assessment is required and
documentation of the work restrictions can proceed as required in Clause 5.
When neither of these questions can be answered positively, additional investigation, hereafter referred to as
“Case 1”, is required as specified in 4.1.4.
The intent of this clause is to find and utilize information that may already exist and that allows the
assessment to be completed without further, more costly and time consuming effort. It is recommended that
experts who are likely to have such information be contacted. Examples of such experts are the pacemaker
manufacturer, equipment manufacturer, employer’s technical department, consultants, or others skilled in
EMI effects with implanted pacemakers.
4.1.3 Patient warning consideration
The responsible physician and pacemaker-Employee shall be consulted to determine the type of and details
for any EMI warnings applicable to the pacemaker.
If the warning is about behaviour of the pacemaker due to interference from particular types of equipment
(see 4.1 (b) (ii)) then it shall first be determined whether that equipment is actually present in the workplace:
• if the equipment is not present, the pacemaker-Employee is allowed to work without restrictions and the
pacemaker specific assessment can be completed and documented as required in Clause 5;
• if the equipment subject to the warning is present, the steps given in 4.1.2 shall be taken.
If the warning is due to the applied settings of the pacemaker that may cause reduced immunity
(see 4.1.1 b) 1)) to EMI that is at or below the reference levels, the responsible physician shall be consulted
to determine whether the settings can be changed to avoid settings that are associated with the warning,
thereby restoring standard immunity levels:
• if it is determined that such a change of settings can be made, the pacemaker-Employee shall be
advised to arrange, through consultation with the responsible physician, for these changes of settings to
be made prior to returning to work. When the change of setting has been completed, the pacemaker-
Employee is allowed to work without restrictions; the results shall be documented as required in
Clause 5 and the assessment is concluded;
• if the settings cannot be changed, then additional investigation, hereafter referred to as “Case 2” is
required as discussed in 4.1.4.
4.1.4 Cases for additional investigation
When the investigation steps shown in Figure 2 have been followed but fail to mitigate or to dismiss risk to
the pacemaker-Employee from the effects of workplace EMI, then an additional investigation shall be
performed as shown in Figure 3 and described in 4.1.5. The goal of the investigation is to determine the
likelihood of a clinically significant response of the pacemaker to the EMI at the workplace that is the result of
the following:
a) Case 1: Equipment is used at the workplace that is:
1) neither listed in, nor used in accordance with, Table A.1, and for which there is no information
available that allows a pre-determination of safe or restricted work for the pacemaker-Employee, or
2) capable of emitting fields that may induce pacemaker lead voltages exceeding the immunity levels
established by conformity with the pacemaker product standard, EN 45502-2-1,
3) known by the pacemaker manufacturer to potentially cause interference with the pacemaker and
there is no applicable safe use guideline available from other sources.
b) Case 2: The responsible physician has prescribed settings of the pacemaker that make it susceptible to
EMI even from equipment listed in Table A.1.
If one of these cases is valid, an additional investigation as shown in Figure 3 and described in 4.1.5 shall be
performed.
Figure 3 — Additional investigation process
4.1.5 Choice of investigative method
4.1.5.1 General
There are two alternative types of investigative methods that may be used:
• clinical (or in vivo) methods directly involving the pacemaker-Employee who is monitored for
interference effects; or
• non-clinical methods based upon a choice of either in vitro or comparative study.
For leadless pacemaker systems only clinical and non-clinical in vitro methods shall be used as comparative
study methods have not yet been established.
If a chosen method provides insufficient information for the risk assessment, further investigation is
necessary.
4.1.5.2 Considerations in choosing a clinical method
Prior to choosing to use a clinical method (for examples, see Annex B), the foreseeable exposure levels shall
be known and the responsible physician should be consulted to determine if it is contraindicated. If it is
contraindicated, a non-clinical method shall be chosen.
NOTE Pacemaker-Employees who are pacemaker dependent, or who may otherwise suffer harm from the effects
of even temporary EMI are examples of those who might be contraindicated.
A clinical method can only be started with consent of the pacemaker-Employee according to national
regulation. When considering the use of a clinical method, a second consideration is the choice of site at
which it should be performed. Generally, the preferred site is the pacemaker-Employee’s workplace, but this
might not be feasible for a number of reasons. Consideration should be given to whether one of the methods
described in Annex B can be performed while the pacemaker-Employee is moving through the workplace or
performing the anticipated job function. Limiting factors can include
• harsh or dirty environments,
• confined spaces,
• inability to provide coincident monitoring by clinical personnel or manufacturer representatives, and their
equipment, possibly due to the specific location or the non-availability of personnel or equipment,
• workplaces consisting of different locations separated geographically or those which are not accessible
to clinicians and / or pacemaker manufacturer representatives,
• workplace situations and equipment that might offer an EMF environment that varies significantly from
day to day such that the exposure provided during a single test might not represent the likely worst
case, or even typical, exposure values for that pacemaker-Employee.
If it is determined that a clinical investigation at the workplace is not feasible, the assessment team may
consider the possibility that the method could be applied in a laboratory setting. At a minimum, the following
two limiting factors should be considered:
• the additional investigation is Case 2, where it is not known which equipment in the workplace may be
the cause of hazardous EMI to the pacemaker-Employee. In such cases it is impractical to bring all
possible workplace equipment to the laboratory for testing;
• the additional investigation is Case 1, involving specific equipment of unknown EMI characteristics,
where the equipment cannot be taken to a laboratory due to considerations of any kind.
If a determination is made to perform a clinical investigation, then one of the methods in Annex B may be
chosen and carried out as described in 4.2.
4.1.5.3 Considerations in choosing a non-clinical method
Alternatively, a non-clinical method may be chosen for the additional investigation, for instance when
• the workplace EMF environment is known to fluctuate significantly from day to day, thereby rendering
additional uncertainty in a single instance of clinical testing,
• the range of field levels associated with the workplace or specific equipment may already be known. In
this case a comparative approach as outlined in 4.3.3 may be readily attempted,
• the clinical approach is impracticable for any of the other reasons given in 4.1.5.2.
If a determination is made to perform a non-clinical method, one of the two methods discussed in 4.3 shall be
chosen.
4.2 Clinical investigation
Once it has been decided to perform a clinical investigation and found to be feasible, it should be carried out
in accordance with national regulation, or else with the requirements of EN ISO 14155.
NOTE 1 These standards define procedures for the conduct and performance of clinical investigations of medical
devices.
This investigation may be performed either in the pacemaker-Employee’s workplace or in a laboratory
setting, as determined in 4.1.5.2.
The assessment team may choose one of the methods described in Annex B. The choice and rationale shall
be documented according to Clause 5.
If the pacemaker-Employee’s situation is Case 1, involving specific equipment, the assessment team should
decide whether to perform the investigation in a provocative or non-provocative manner. The choice shall be
documented and a test plan prepared, reviewed and approved by the assessment team:
• a non-provocative test subjects the pacemaker-Employee to all exposure situations associated with the
equipment that are anticipated to be present during the normal execution of their duties. Such a test
should include closest expected distances and orientations relative to the equipment, as well as a
duration of exposure sufficient to determine whether clinically significant EMI effects should have
occurred.
• a provocative test subjects the pacemaker-Employee to exposure situations that include decreased
distances or longer exposure durations than are anticipated during normal execution of their job duties.
These exposures shall be planned and executed to protect the safety of the pacemaker-Employee. The
advantage of this approach is that it may reveal a boundary of safe exposure and/or a duration of
transient exposure. In this case, the residual risk is reduced since the safe exposure conditions are
more fully known.
NOTE 2 Where available, information about the known range of field levels compared with the actual levels during the
tests can reduce the residual risk.
NOTE 3 If the pacemaker-Employee’s situation is Case 2, a provocative clinical test might not be recommended
when exposure to many items of equipment or areas of access in the workplace would be required.
4.3 Non-clinical investigation
4.3.1 General
There are two methods for the non-clinical investigation:
• in vitro testing, involving the use of a pacemaker device and lead inserted into an EM phantom suitable
for e.g. the frequency range under consideration that is then exposed to the EMF at the workplace;
• comparative study, involving characterization of the EMF at the workplace and a prediction of the effects
on the employee’s pacemaker through analysis and comparison with pacemaker immunity levels.
The following factors may be considered when making the choice of which method of non-clinical
investigation to use:
• in vitro testing shall be performed using an IPG and leads of the same make and model as those
implanted in the pacemaker-Employee. If the in vitro method is chosen, it should be performed in
accordance with the requirements of 4.3.2;
• a comparative study requires the determination of induced voltages and pacemaker immunity. If the
Comparative study method is chosen, it should be performed in accordance with the requirements of
4.3.3 and shown in Figure 4.
4.3.2 Non-clinical investigation by in vitro testing
4.3.2.1 Determination of in vitro testing feasibility
The following requirements are necessary to perform an in vitro test:
• the workplace environment is such that an EM phantom, device programmer, and test personnel can be
accommodated for the duration of anticipated testing;
• a fully functional pacemaker and leads, if applicable, of the same make and model as that implanted in
the pacemaker-Employee can be obtained from the manufacturer or the physician;
• a device programmer compatible with the pacemaker-Employee’s pacemaker is available and capable
of device interrogation with up-to-date programming software;
• the approximate lead layout as implanted in the pacemaker-Employee is known and available.
General information may be available from in vitro studies about the behaviour of a variety of pacemaker
types and settings in specific types of electromagnetic fields. These may contain useful information about the
exposure under consideration. It may be possible to use these results to make conservative judgements
about particular exposure situations. Care should be taken as the specific implantation of the pacemaker-
Employee is not necessarily included in the studies.
4.3.2.2 Requirements for in vitro testing
The pre-requisites given in 4.3.2.1 shall be met. The pacemaker and leads, if applicable, shall be arranged
within an EM phantom so as to approximate the layout known for the pacemaker-Employee. The pacemaker
shall be programmed with the same parameters and have the same operating software as that existing for
the pacemaker-Employee.
A test plan shall be prepared that defines the following:
• the exposure situations (orientation, distance and duration) to be used for the testing, whether it is to
evaluate EMI with specific equipment or within workplace areas;
• methods and configurations for testing to detect effects, such as pacing inhibition, rate tracking, or
asynchronous pacing;
• criteria for results observation, recording, and interpretation, including a definition of which effects
should be considered clinically significant for the pacemaker-Employee in question;
• provisions for monitoring the IPG behaviour in the presence of the fields. Since the level of applied fields
may be higher than those specified in the product test standard EN 45502-2-1, ca
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