SIST EN 60601-2-33:2010

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Medizinische elektrische Geräte - Teil 2-33: Besondere Festlegungen für die Sicherheit von Magnetresonanzgeräten für die medizinische Diagnostik (IEC 60601-2-33:2010)Appareils électromédicaux - Partie 2-33: Exigences particulières pour la sécurité de base et les performances essentielles des appareils à résonance magnétique utilisés pour le diagnostic médical (CEI 60601-2-33:2010)Medical electrical equipment - Part 2-33: Particular requirements for the basic safety and essential performance of magnetic resonance equipment for medical diagnosis (IEC 60601-2-33:2010)11.040.55Diagnostic equipmentICS:Ta slovenski standard je istoveten z:EN 60601-2-33:2010SIST EN 60601-2-33:2010en01-december-2010SIST EN 60601-2-33:2010SLOVENSKI
STANDARDSIST EN 60601-2-33:2003/A2:2008SIST EN 60601-2-33:2003/A1:2007SIST EN 60601-2-33:20031DGRPHãþD

EUROPEAN STANDARD EN 60601-2-33 NORME EUROPÉENNE
EUROPÄISCHE NORM October 2010
CENELEC European Committee for Electrotechnical Standardization Comité Européen de Normalisation Electrotechnique Europäisches Komitee für Elektrotechnische Normung
Management Centre: Avenue Marnix 17, B - 1000 Brussels
© 2010 CENELEC -
All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 60601-2-33:2010 E
ICS 11.040.55 Supersedes EN 60601-2-33:2002 + A1:2005 + A2:2008
English version
Medical electrical equipment -
Part 2-33: Particular requirements for the basic safety and essential performance of magnetic resonance equipment for medical diagnosis (IEC 60601-2-33:2010)
Appareils électromédicaux -
Partie 2-33: Exigences particulières pour la sécurité de base et les performances essentielles des appareils à résonance magnétique utilisés pour le diagnostic médical (CEI 60601-2-33:2010)
Medizinische elektrische Geräte -
Teil 2-33: Besondere Festlegungen für die Sicherheit von Magnetresonanzgeräten für die medizinische Diagnostik (IEC 60601-2-33:2010)
This European Standard was approved by CENELEC on 2010-10-01. 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 Central Secretariat 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 Central Secretariat has the same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom.
Foreword The text of document 62B/777/FDIS, future edition 3 of IEC 60601-2-33, prepared by SC 62B, Diagnostic imaging equipment, of IEC TC 62, Electrical equipment in medical practice, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 60601-2-33 on 2010-10-01. This European Standard supersedes EN 60601-2-33:2002 + A1:2005 + A2:2008. This EN 60601-2-33:2010 is based on the second amendment to EN 60601-2-33:2002. It has also been adapted to EN 60601-1:2006, with technical modifications being introduced where appropriate. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and CENELEC shall not be held responsible for identifying any or all such patent rights. The following dates were fixed: – latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement
(dop)
2011-07-01 – latest date by which the national standards conflicting
with the EN have to be withdrawn
(dow)
2013-10-01 In this standard, the following print types are used: –
Requirements and definitions: roman type. –
Test specifications: italic type. –
Informative material appearing outside of tables, such as notes, examples and references: in smaller type. Normative text of tables is also in a smaller type. –
TERMS DEFINED IN CLAUSE 3 OF THE GENERAL STANDARD, IN THIS PARTICULAR STANDARD OR AS NOTED: SMALL CAPITALS. In referring to the structure of this standard, the term –
“clause” means one of the seventeen numbered divisions within the table of contents, inclusive of all subdivisions (e.g. Clause 7 includes subclauses 7.1, 7.2, etc.); –
“subclause” means a numbered subdivision of a clause (e.g. 7.1, 7.2 and 7.2.1 are all subclauses of Clause 7). References to clauses within this standard are preceded by the term “Clause” followed by the clause number. References to subclauses within this particular standard are by number only.
In this standard, the conjunctive “or” is used as an “inclusive or” so a statement is true if any combination of the conditions is true. The verbal forms used in this standard conform to usage described in Annex H of the ISO/IEC Directives, Part 2. For the purposes of this standard, the auxiliary verb: –
“shall” means that compliance with a requirement or a test is mandatory for compliance with this standard; –
“should” means that compliance with a requirement or a test is recommended but is not mandatory for compliance with this standard; –
“may” is used to describe a permissible way to achieve compliance with a requirement or test. An asterisk (*) as the first character of a title or at the beginning of a paragraph or table title indicates that there is guidance or rationale related to that item in Annex AA. SIST EN 60601-2-33:2010

- 3 - EN 60601-2-33:2010 This European Standard has been prepared under a mandate given to CENELEC by the European Commission and the European Free Trade Association and covers essential requirements of EC Directive 93/42/EEC. See Annex ZZ. Annexes ZA and ZZ have been added by CENELEC. __________ Endorsement notice The text of the International Standard IEC 60601-2-33:2010 was approved by CENELEC as a European Standard without any modification. __________
Annex ZA
(normative)
Normative references to international publications with their corresponding European publications
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
NOTE
When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD applies.
Clause 2 of the general standard applies except as follows: Publication Year Title EN/HD Year
Replacement:
IEC 60601-1 2005 Medical electrical equipment -
Part 1: General requirements for basic safety and essential performance EN 60601-1 + corr. March
2006 2010
Addition:
IEC 60601-1-2 (mod) 2007 Medical electrical equipment -
Part 1-2: General requirements for basic safety and essential performance - Collateral standard: Electromagnetic compatibility - Requirements and tests EN 60601-1-2 + corr. March
2007 2010
NEMA MS 4 2006 Acoustic noise measurement procedure for diagnostic magnetic resonance imaging (MRI) devices - -
NEMA MS 8 2008 Characterization of the specific absorption rate (SAR) for magnetic resonance imaging systems - -
- 5 - EN 60601-2-33:2010 Annex ZZ (informative)
Coverage of Essential Requirements of EC Directives
This European Standard has been prepared under a mandate given to CENELEC by the European Commission and the European Free Trade Association and within its scope the standard covers all relevant essential requirements as given in Annex I of the EC Directive 93/42/EEC with the exception of ERs 3, 4, 7.1 and 12.1. Compliance with this standard provides one means of conformity with the specified essential requirements of the Directive concerned. WARNING: Other requirements and other EC Directives may be applicable to the products falling within the scope of this standard.
IEC 60601-2-33Edition 3.0 2010-03INTERNATIONAL STANDARD NORME INTERNATIONALEMedical electrical equipment –
Part 2-33: Particular requirements for the basic safety and essential performance of magnetic resonance equipment for medical diagnosis
Appareils électromédicaux –
Partie 2-33: Exigences particulières pour la sécurité de base et les performances essentielles des appareils à résonance magnétique utilisés pour le diagnostic médical
INTERNATIONAL ELECTROTECHNICAL COMMISSION COMMISSION ELECTROTECHNIQUE INTERNATIONALE XEICS 11.040.55 PRICE CODECODE PRIXISBN 2-8318-1081-8
– 2 – 60601-2-33 © IEC:2010 CONTENTS FOREWORD.54 INTRODUCTION.6H6H7 201.1 Scope, object and related standards.7H7H8 201.2 Normative references.8H8H9 201.3 Terms and definitions.9H9H10 201.4 General requirements.10H10H15 201.5 General requirements for testing of ME EQUIPMENT.11H11H15 201.6 Classification of ME EQUIPMENT and ME SYSTEMS.12H12H15 201.7 ME EQUIPMENT identification, marking and documents.13H13H16 201.8 Protection against electrical HAZARDS from ME EQUIPMENT.14H14H27 201.9 Protection against mechanical HAZARDs of ME EQUIPMENT and ME SYSTEMS.15H15H28 201.10 Protection against unwanted and excessive radiation HAZARDS.16H16H28 201.11 Protection against excessive temperatures and other HAZARDS.17H17H28 201.12 Accuracy of controls and instruments and protection against hazardous outputs.18H18H29 201.13 HAZARDOUS SITUATIONS and fault conditions.19H19H47 201.14 PROGRAMMABLE ELECTRICAL MEDICAL SYSTEM (PEMS).20H20H47 201.15 Construction of ME EQUIPMENT.21H21H47 201.16 ME SYSTEMS.22H22H47 201.17 Electromagnetic compatibility of ME EQUIPMENT and ME SYSTEMS.23H23H47 202 Electromagnetic compatibility – Requirements and tests.24H24H48 Annexes.25H25H48 Annex D (informative)
Symbols on marking.26H26H49 Annex AA (informative)
Particular guidance and rationale.27H27H51 Bibliography.28H28H96 Index of defined terms used in this particular standard.29H29H104
Figure 201.101 – Gradient waveform and EFFECTIVE STIMULUS DURATION.30H30H11 Figure 201.102 – Limits for cardiac and peripheral nerve stimulation.31H31H33 Figure 201.103 – Reduction of WHOLE BODY SAR limits at high temperatures.32H32H37 Figure 201.104 – Volume for determining the spatial maximum of gradient output.33H33H43 Figure 201.105 – Volume for determining the B1 stray field.34H34H46 Figure 201.D.101 – Signs indicating a transmit only RF coil, transmit / receive RF coil and a receive only RF coil.35H35H50 Figure AA.1 – Static magnetic fields: flow potentials and retardation.36H36H68 Figure AA.2 – Experimental data on PNS threshold of human volunteers
in WHOLE BODY MR EQUIPMENT.37H37H83 Figure AA.3 – Double logarithmic plot of experimental threshold values
for peripheral nerve stimulation.38H38H84 Figure AA.4 – Response value R(t) generated by convolution of a rectangular stimulus dB/dt and a nerve impulse response function n(t-θ).39H39H88 Figure AA.5 – Gradient waveform G, stimulus waveform dB/dt and response value R,
for a trapezoid EPI waveform starting at t = 0.40H40H89 SIST EN 60601-2-33:2010

60601-2-33 © IEC:2010 – 3 – Figure AA.6 – Threshold values dB/dt for two gradient waveforms,
plotted against EFFECTIVE STIMULUS DURATION.41H41H89 Figure AA.7 – Threshold value of dB/dt for a sinusoid gradient waveform,
as function of the number of half periods in the waveform.42H42H90 Figure AA.8 – SAR limits for the exposed mass of a PATIENT.43H43H93
Table 201.101 – List of symbols.44H44H15 Table 201.102 – Rheobase values per type of gradient system.45H45H32 Table 201.103 – Weight factors for summation of the
maximum output Oi per GRADIENT UNIT.46H46H34 Table 201.104 – Temperature limits.47H47H34 Table 201.105 – SAR limits for volume transmit coils.48H48H35 Table 201.106 – SAR limits for local transmit coils.49H49H36 Table 201.D.101 – Examples of warning signs and prohibitive signs):.50H50H49 Table AA.1 – Static field occupational standards.51H51H67
– 4 – 60601-2-33 © IEC:2010 INTERNATIONAL ELECTROTECHNICAL COMMISSION ____________
MEDICAL ELECTRICAL EQUIPMENT –
Part 2-33: Particular requirements for the basic safety and essential
performance of magnetic resonance equipment for medical diagnosis
FOREWORD 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with may participate in this preparatory work. International, governmental and non-governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for Standardization (ISO) in accordance with conditions determined by agreement between the two organizations. 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international consensus of opinion on the relevant subjects since each technical committee has representation from all interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any misinterpretation by any end user. 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications transparently to the maximum extent possible in their national and regional publications. Any divergence between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter. 5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any services carried out by independent certification bodies. 6) All users should ensure that they have the latest edition of this publication. 7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and members of its technical committees and IEC National Committees for any personal injury, property damage or other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is indispensable for the correct application of this publication. 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent rights. IEC shall not be held responsible for identifying any or all such patent rights. International standard IEC 60601-2-33 has been prepared by IEC subcommittee 62B: Diagnostic imaging equipment, of IEC technical committee 62: Electrical equipment in medical practice. This third edition cancels and replaces the second edition published in 2002, its Amendment 1 (2005) and Amendment 2 (2007) and constitutes a technical revision. This third edition of IEC 60601-2-33 is based on the second amendment to Edition 2. It has also been adapted to the third edition of IEC 60601-1 (2005), with technical modifications being introduced where appropriate. SIST EN 60601-2-33:2010

60601-2-33 © IEC:2010 – 5 – The text of this particular standard is based on the following documents: FDIS Report on voting 62B/777/FDIS 62B/782/RVD
Full information on the voting for the approval of this particular standard can be found in the report on voting indicated in the above table. This publication has been drafted in accordance with the ISO/IEC Directives, Part 2. In this standard, the following print types are used: – Requirements and definitions: roman type. – Test specifications: italic type. – Informative material appearing outside of tables, such as notes, examples and references: in smaller type. Normative text of tables is also in a smaller type. – TERMS DEFINED IN CLAUSE 3 OF THE GENERAL STANDARD, IN THIS PARTICULAR STANDARD OR AS NOTED: SMALL CAPITALS. In referring to the structure of this standard, the term – “clause” means one of the seventeen numbered divisions within the table of contents, inclusive of all subdivisions (e.g. Clause 7 includes subclauses 7.1, 7.2, etc.); – “subclause” means a numbered subdivision of a clause (e.g. 7.1, 7.2 and 7.2.1 are all subclauses of Clause 7). References to clauses within this standard are preceded by the term “Clause” followed by the clause number. References to subclauses within this particular standard are by number only. In this standard, the conjunctive “or” is used as an “inclusive or” so a statement is true if any combination of the conditions is true. The verbal forms used in this standard conform to usage described in Annex H of the ISO/IEC Directives, Part 2. For the purposes of this standard, the auxiliary verb: – “shall” means that compliance with a requirement or a test is mandatory for compliance with this standard; – “should” means that compliance with a requirement or a test is recommended but is not mandatory for compliance with this standard; – “may” is used to describe a permissible way to achieve compliance with a requirement or test. An asterisk (*) as the first character of a title or at the beginning of a paragraph or table title indicates that there is guidance or rationale related to that item in Annex AA. A list of all parts of the IEC 60601 series, published under the general title: Medical electrical equipment, can be found on the IEC website. SIST EN 60601-2-33:2010

– 6 – 60601-2-33 © IEC:2010 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 web site 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.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates that it contains colours which are considered to be useful for the correct understanding of its contents. Users should therefore print this document using a colour printer.
60601-2-33 © IEC:2010 – 7 – * INTRODUCTION This particular standard is written at a moment in which the technical evolution of MR EQUIPMENT is in rapid progress and the scientific foundation of its safe use is still expanding. This International Standard addresses technical aspects of the medical diagnostic MR SYSTEM and the MR EQUIPMENT therein related to the safety of PATIENTS examined with this system, the safety of the MR WORKER involved with its operation and the safety of the MR WORKER involved with the development, manufacturing, installation, and servicing of the MR SYSTEM. Where limits of electromagnetic fields (EMF) exposure of PATIENTS and MR WORKERS are stated, these limits do not imply that such levels of exposure can be assumed to be acceptable for workers in other professional settings and for the population at large. The limits provide a sensible balance between RISKS for the PATIENTS and MR WORKERS and benefits for the PATIENTS.
Organizational aspects of safety are the task of the RESPONSIBLE ORGANIZATION. This task includes adequate training of staff, rules of access to the MR SYSTEM, qualification of staff for decisions that are related to safety, definition of medical responsibility and specific requirements for personnel following from that responsibility when the PATIENT is in or near the MR SYSTEM. Examples of such organizational aspects are:
− operation in FIRST LEVEL CONTROLLED OPERATING MODE;
− emergency procedures for resuscitation of the PATIENT who is in the MR SYSTEM; − emergency procedures after a QUENCH of the superconductive magnet when present;
− set-up and maintenance of a protocol for screening the PATIENT for contraindications or for conditions that may affect acceptable exposure; − rules for ROUTINE MONITORING and for MEDICAL SUPERVISION of the PATIENT during the exam. − rules to minimize and to limit the exposure of MR WORKERS to EMF. Extensive rationale is provided in Annex AA for some of the definitions and requirements in order to provide the user of this standard with a reasonably complete access to the source material that was used in support of the considerations during drafting. The relationship of this particular standard with IEC 60601-1 and the collateral standards is explained in subclauses 201.1.3 and 201.1.4. The introduced EMF exposure limits required in this standard for an MR WORKER will never exceed those allowed for PATIENTS
All exposure limits allowed for a PATIENT and for an MR WORKER are expected to protect them against negative health effects and unacceptable RISKS.
For the exposure to static magnetic fields, subjective short-term physiological and sensory effects are expected. These influence the well being of the MR WORKER marginally and only during or shortly after exposure.
For the exposure to GRADIENT OUTPUT and RF transmit fields, normally no short-term physiological and sensory effects are expected for MR WORKERS. In addition no experimental or theoretical basis for cumulative biological effects in humans, resulting from exposure at the allowed levels has been generally accepted. The requirements for acoustic noise exposure are different for PATIENTS and MR WORKERS. SIST EN 60601-2-33:2010

– 8 – 60601-2-33 © IEC:2010 MEDICAL ELECTRICAL EQUIPMENT –
Part 2-33: Particular requirements for the basic safety and essential
performance of magnetic resonance equipment for medical diagnosis
201.1 Scope, object and related standards Clause 1 of the general standard1F0F1) applies, except as follows: 201.1.1 Scope Replacement: This International Standard applies to the BASIC SAFETY and ESSENTIAL PERFORMANCE of MR EQUIPMENT and MR SYSTEMS, hereafter referred to also as ME EQUIPMENT. This standard does not cover the application of MR EQUIPMENT beyond the INTENDED USE. If a clause or subclause is specifically intended to be applicable to ME EQUIPMENT only, or to ME SYSTEMS only, the title and content of that clause or subclause will say so. If that is not the case, the clause or subclause applies both to ME EQUIPMENT and to ME SYSTEMS, as relevant.
The standard does not formulate ESSENTIAL PERFORMANCE requirements related to INTERVENTIONAL MR EXAMINATIONS. 201.1.2 Object Replacement: The object of this particular standard is to establish particular BASIC SAFETY and ESSENTIAL PERFORMANCE requirements for MR EQUIPMENT to provide protection for the PATIENT and the MR WORKER. NOTE This standard presumes that the MR WORKERS are properly medically screened, and properly trained and instructed in their duties. 201.1.3 Collateral standards Addition: This particular standard refers to those applicable collateral standards that are listed in Clause 2 of the general standard and Clause 201.2 of this particular standard. IEC 60601-1-2:2007 applies as modified in Clause 202. IEC 60601-1-3 and IEC 60601-1-10 do not apply. All other published collateral standards in the IEC 60601-1 series apply as published. 201.1.4 Particular standards Replacement: ————————— 1) The general standard is IEC 60601-1:2005, Medical electrical equipment – Part 1: General requirements for basic safety and essential performance SIST EN 60601-2-33:2010

60601-2-33 © IEC:2010 – 9 – In the IEC 60601 series, particular standards may modify, replace or delete requirements contained in the general standard and collateral standards as appropriate for the particular ME EQUIPMENT under consideration, and may add other BASIC SAFETY and ESSENTIAL PERFORMANCE requirements. A requirement of a particular standard takes priority over the general standard. For brevity, IEC 60601-1 is referred to in this particular standard as the general standard. Collateral standards are referred to by their document number. The numbering of clauses and subclauses of this particular standard corresponds to that of the general standard with the prefix “201” (e.g. 201.1 in this standard addresses the content of Clause 1 of the general standard) or applicable collateral standard with the prefix “20x” where x is the final digit(s) of the collateral standard document number (e.g. 202.4 in this particular standard addresses the content of Clause 4 of the 60601-1-2 collateral standard, 203.4 in this particular standard addresses the content of Clause 4 of the 60601-1-3 collateral standard, etc.). The changes to the text of the general standard are specified by the use of the following words: "Replacement" means that the clause or subclause of the general standard or applicable collateral standard is replaced completely by the text of this particular standard. "Addition" means that the text of this particular standard is additional to the requirements of the general standard or applicable collateral standard. "Amendment" means that the clause or subclause of the general standard or applicable collateral standard is amended as indicated by the text of this particular standard. Subclauses, figures or tables which are additional to those of the general standard are numbered starting from 201.101. However due to the fact that definitions in the general standard are numbered 3.1 through 3.139, additional definitions in this standard are numbered beginning from 201.3.201. Additional annexes are lettered AA, BB, etc., and additional items aa), bb), etc. Subclauses, figures or tables which are additional to those of a collateral standard are numbered starting from 20x, where “x” is the number of the collateral standard, e.g. 202 for IEC 60601-1-2, 203 for IEC 60601-1-3, etc. The term "this standard" is used to make reference to the general standard, any applicable collateral standards and this particular standard taken together. Where there is no corresponding clause or subclause in this particular standard, the clause or subclause of the general standard or applicable collateral standard, although possibly not relevant, applies without modification; where it is intended that any part of the general standard or applicable collateral standard, although possibly relevant, is not to be applied, a statement to that effect is given in this particular standard. 201.2 Normative references NOTE Informative references are listed in the bibliography beginning on page 52H52H96. Clause 2 of the general standard applies except as follows: Replacement: SIST EN 60601-2-33:2010

– 10 – 60601-2-33 © IEC:2010 IEC 60601-1-2:2007, Medical electrical equipment – Part 1-2: General requirements for basic safety and essential performance – Collateral standard: Electromagnetic compatibility – Requirements and tests Addition: IEC 60601-1:2005, Medical electrical equipment – Part 1: General requirements for basic safety and essential performance NEMA MS 4:2006, Acoustic noise measurements procedure for diagnostic magnetic resonance imaging devices NEMA MS 8:2008, Characterization of the specific absorption rate (SAR) for magnetic resonance imaging systems 201.3 Terms and definitions For the purposes of this document, the terms and definitions given in IEC 60601-1:2005 and the following apply: NOTE An index of defined terms is found beginning on page 53H53H104. A list of symbols used in the document is provided in Table 201.101. Addition: * 201.3.201 B1RMS root mean square (rms) of B1, the radio frequency magnetic induction .d))((x021RMS1xtttBBt∫=
where t is time, and tx is the evaluation time, and is estimated at the RF transmit coil centre. 201.3.202 COMPLIANCE VOLUME PATIENT accessible space in which compliance of GRADIENT OUTPUT is inspected
In MR EQUIPMENT with a cylindrical WHOLE BODY MAGNET, the COMPLIANCE VOLUME is a cylinder with its axis coinciding with the magnet axis and with a radius of 0,20 m. and with a length equal to the gradient coil In MR EQUIPMENT with a TRANSVERSE FIELD MAGNET and a WHOLE BODY GRADIENT SYSTEM, the COMPLIANCE VOLUME is a cylinder aligned with the patient’s axis, of length equal to the gradient coil diameter, and a diameter of 0,40 m or equal to the distance between the poles of the magnet, whichever is less.
In all other MR EQUIPMENT the COMPLIANCE VOLUME is the volume where any part of a PATIENT body can be properly located according to the INTENDED USE of the MR EQUIPMENT. 201.3.203 CONTROLLED ACCESS AREA area to which access is controlled for safety reasons 201.3.204 CORE TEMPERATURE
mean temperature of the body core SIST EN 60601-2-33:2010

60601-2-33 © IEC:2010 – 11 – NOTE Typically equal to the rectal, sublingual, or tympanic temperature. More reliable representations of CORE TEMPERATURE are oesophageal or arterial blood temperature. Brain temperatures are CORE TEMPERATUREs. 201.3.205 EFFECTIVE STIMULUS DURATION ts,eff
duration of any period of the monotonic increasing or decreasing gradient, used to describe its limits for cardiac or peripheral nerve stimulation, defined as the ratio of the peak-to-peak field variation and the maximum value of the time derivative of the gradient in that period (see Figure 201.101)
Graph a Gmax Time G dB/dt (dB/dt)max ts,eff Graph b Graph aG magnetic field gradient, T/m Gmax maximum of gradient, T/m
Graph b dB/dt time rate of change of magnetic field, T/m/s (dB/dt)max
maximum of
time rate of change
of magnetic field, T/m/s ts,eff effective stimulus duration, s ts,eff ts,eff IEC
402/10
Three periods of monotonic change of the gradient G are shown in graph a. The corresponding GRADIENT OUTPUT dB/dt is shown in graph b and the EFFECTIVE STIMULUS DURATION ts,eff is indicated. Figure 201.101 – Gradient waveform and EFFECTIVE STIMULUS DURATION 201.3.206 EMERGENCY FIELD SHUT DOWN UNIT device for de-energizing a superconducting or resistive magnet in case of an emergency situation * 201.3.207 ENVIRONMENTAL TEMPERATURE temperature [°C] of a uniform (isothermal) “black” enclosure in which an occupant would exchange the same amount of heat by radiation and convection as in the actual non-uniform environment NOTE For the calculation of the ENVIRONMENTAL TEMPERATURE see rationale in Annex AA. 201.3.208 FIRST LEVEL CONTROLLED OPERATING MODE mode of operation of the MR EQUIPMENT in which one or more outputs reach a value that can cause physiological stress to PATIENTS which needs to be controlled by MEDICAL SUPERVISION 201.3.209 GRADIENT OUTPUT parameter characterizing the gradient performance such as rate of change of the magnitude of the magnetic field, or electric field induced by one or more GRADIENT UNITS under specified conditions and at a specified position SIST EN 60601-2-33:2010

– 12 – 60601-2-33 © IEC:2010 201.3.210 GRADIENT UNIT all gradient coils and amplifiers that together generate a magnetic field gradient along one of the axes of the coordinate system of the MR EQUIPMENT 201.3.211 HEAD RF TRANSMIT COIL VOLUME RF TRANSMIT COIL suitable for use in MR EQUIPMENT for a MR EXAMINATION of the PATIENT’s head 201.3.212 HEAD SAR SAR averaged over the mass of the head and over a specified time * 201.3.213 INTERVENTIONAL MR EXAMINATION MR EXAMINATION applied to guide a medical (including invasive) procedure e.g. biopsy or the treatment of a lesion 201.3.214 ISOCENTRE in MR EQUIPMENT null point of the spatially encoding gradients NOTE 1 Typically this also corresponds to the region of highest magnet homogeneity
[IEC 62464-1:2007, definition 3.1.15] NOTE 2 Typically this corresponds with the position in the system targeted for imaging. 201.3.215 LOCAL RF TRANSMIT COIL RF transmit coil other than a VOLUME RF TRANSMIT COIL 201.3.216 LOCAL SAR SAR averaged over any 10 g of tissue of the body and over a specified time * 201.3.217 MAGNETIC RESONANCE MR resonant absorption of electromagnetic energy by an ensemble of atomic nuclei situated in a magnetic field 201.3.218 MAGNETIC RESONANCE EQUIPMENT MR EQUIPMENT MEDICAL ELECTRICAL EQUIPMENT which is intended for in vivo MAGNETIC RESONANCE EXAMINATION of a PATIENT comprising all parts in hardware and software from the SUPPLY MAINS to the display monitor NOTE The MR EQUIPMENT is a PROGRAMMABLE ELECTRICAL MEDICAL SYSTEM (PEMS). 201.3.219 MAGNETIC RESONANCE EXAMINATION MR EXAMINATION process of acquiring data by MAGNETIC RESONANCE from a PATIENT SIST EN 60601-2-33:2010

60601-2-33 © IEC:2010 – 13 – 201.3.220 MAGNETIC RESONANCE SYSTEM MR SYSTEM ensemble of MR EQUIPMENT, ACCESSORIES including means for display, control, energy supplies, and the CONTROLLED ACCESS AREA, where provided * 201.3.221 MAGNETIC RESONANCE WORKER MR WORKER person that because of his/her profession has to enter the CONTROLLED ACCESS AREA or equivalent of the MAGNETIC RESONANCE SYSTEM NOTE Other persons, such as MR volunteers and PATIENT carers, are not covered by this definition. However, OPERATORS and staff are included in this definition (see rationale). 201.3.222 MAXIMUM GRADIENT SLEW RATE the rate of change of the gradient obtained by switching the GRADIENT UNIT between its maximum specified gradient strengths G+max and G−max in the shortest possible ramp time obtainable under normal scan conditions * 201.3.223 MEDICAL SUPERVISION adequate medical management of PATIENTS who can be at RISK from some parameters of exposure to the MR EQUIPMENT, either because of the medical condition of the PATIENT, the levels of exposure or a combination 201.3.224 NORMAL OPERATING MODE mode of operation of the MR EQUIPMENT in which none of the outputs have a value that can cause physiological stress to PATIENTS 201.3.225 PARTIAL BODY SAR SAR averaged over the mass of the body that is exposed by the VOLUME RF TRANSMIT COIL and over a specified time 201.3.226 PNS OUTPUT value which estimates the level of peripheral nerve stimulation (PNS) for the PATIENT 201.3.227 PNS THRESHOLD LEVEL value of the PNS OUTPUT related to the onset of PNS sensation for the PATIENT 201.3.228 QUENCH transition of the electrical conductivity of a coil that is carrying a current from a super-conducting state to normal conductivity, resulting in rapid boil-off of fluid cryogen and decay of the magnetic field 201.3.229 ROUTINE MONITORING routine PATIENT monitoring, carried out by responsible personnel such as the OPERATOR and staff of the MR EQUIPMENT and consisting of audio and/or visual contact, as appropriate with the PATIENT during the MR EXAMINATION SIST EN 60601-2-33:2010

– 14 – 60601-2-33 © IEC:2010 201.3.230 SEARCH COIL a small diameter coil used in a compliance test to measure GRADIENT OUTPUT 201.3.231 SECOND LEVEL CONTROLLED OPERATING MODE mode of operation of the MR EQUIPMENT in which one or more outputs reach a value that can produce significant RISK for PATIENTS, for which explicit ethical approval is required (i.e. a human studies protocol approved to local requirements) 201.3.232 SPECIAL PURPOSE GRADIENT SYSTEM gradient system suitable for use in MR EQUIPMENT for a special purpose NOTE An example of a SPECIAL PURPOSE GRADIENT SYSTEM is a gradient system that can be incorporated in MR EQUIPMENT to allow special examination of the head of the PATIENT. * 201.3.233 SPECIFIC ABSORPTION RATE SAR radio frequency power absorbed per unit of mass (W/kg) 201.3.234 TIME RATE OF CHANGE OF THE MAGNETIC FIELD dB/dt rate of change of the magnetic flux density with time (T/s) 201.3.235 TRANSVERSE FIELD MAGNET magnet for which the field is at right angles to the axial direction of the PATIENT 201.3.236 VOLUME RF TRANSMIT COIL RF transmit coil suitable for use in MR EQUIPMENT that produces a homogeneous RF field over an extended volume encompassed by the coil NOTE The VOLUME RF TRANSMIT COIL can be a WHOLE BODY RF TRANSMIT COIL, a HEAD RF TRANSMIT COIL or a RF TRANSMIT COIL designed for homogeneous exposure of a specific part of the body. A single loop coil enclosing the body or a part of the body is considered to be a VOLUME RF TRANSMIT COIL (example: single loop wrist coil). 201.3.237 WHOLE BODY GRADIENT SYSTEM gradient system suitable for use in WHOLE BODY MR EQUIPMENT 201.3.238 WHOLE BODY MAGNET magnet suitable for use in WHOLE BODY MR EQUIPMENT 201.3.239 WHOLE BODY MAGNETIC RESONANCE EQUIPMENT WHOLE BODY MR EQUIPMENT MR EQUIPMENT of sufficient size to allow whole body MR EXAMINATION and partial body MR EXAMINATION of adult PATIENTS. It can be equipped with VOLUME RF TRANSMIT COILS, LOCAL RF TRANSMIT COILS and with a SPECIAL PURPOSE GRADIENT SYSTEM 201.3.240 WHOLE BODY RF TRANSMIT COIL VOLUME RF TRANSMIT COIL of sufficient size for whole body examinations of adult PATIENTS SIST EN 60601-2-33:2010

60601-2-33 © IEC:2010 – 15 – 201.3.241 WHOLE BODY SAR SAR averaged over the total mass of the body and over a specified time Table 201.101 – List of symbols Symbol SI-Unit Definition B0 T Static magnetic field
B1 T Magnetic induction of the radio frequency magnetic field B1RMS T Root mean square of B1 dB/dt T/s TIME RATE OF CHANGE OF THE MAGNETIC FIELD (dB/dt) E V/m Electric field induced by gradient switching G T/m Magnetic field gradient
L01 V/m or T/s Limit of the GRADIENT OUTPUT for the NORMAL OPERATING MODE L12 V/m or T/s Limit of the GRADIENT OUTPUT for the FIRST LEVEL CONTROLLED OPERATING MODE O depending on context PNS OUTPUT Oi depending on context PNS OUTPUT per GRADIENT UNIT rb V/m or T/s Rheobase
SAR W/kg SPECIFIC ABSORPTION RATE (SAR) ts,eff ms EFFECTIVE STIMULUS DURATION tSAR min Averaging time for the determination of SAR
T oC Temperature wi none Weight factor per GRADIENT UNIT relating the GRADIENT OUTPUT of that unit to the limit
201.4 General requirements Clause 4 of the general standard applies. except as follows: 201.4.3 ESSENTIAL PERFORMANCE Addition:
NOTE 101 No ESSENTIAL PERFORMANCE requirements have been identified for the MR EQUIPMENT within the scope of the standard. 201.5 General requirements for testing of ME EQUIPMENT Clause 5 of the general standard applies except as follows: 201.5.7 Humidity preconditioning treatment Addition:
For those MR SYSTEMS that are to be used only in controlled environments, as to be specified in the technical description, no humidity preconditioning is required. 201.6 Classification of ME EQUIPMENT and ME SYSTEMS Clause 6 of the general standard applies. SIST EN 60601-2-33:2010

– 16 – 60601-2-33 © IEC:2010 201.7 ME EQUIPMENT identification, marking and documents Clause 7 of the general standard applies except as follows: 201.7.9 ACCOMPANYING DOCUMENTS 201.7.9.1 General Addition: The ACCOMPANYING DOCUMENTS should provide sufficient information to the RESPONSIBLE ORGANIZATION to enable it to comply with the local regulations and requirements for exposure limits appropriate to the PATIENT and MR WORKER.
201.7.9.2 Instructions for use 201.7.9.2.10 Messages Replacement: The instructions for use shall list all system messages, error messages, and fault messages that are generated related to safety concerns unless these messages are self-explanatory. Addition: * 201.7.9.2.101 Instructions for use for MR EQUIPMENT * a) Pre-screening of the PATIENT and the MR WORKER
Instructions for use shall provide clear recommendations to the RESPONSIBLE ORGANIZATION regarding pre-screening of PATIENTS and MR WORKERS. This specifically applies to those PATIENTS and MR WORKERS who could be placed at RISK due to their professional activity, past medical history, present medical state and/or the physical environment of the MR EQUIPMENT. These instructions shall indicate the need for a pre-screening programme to identify such PATIENTS and MR WORKERS at RISK, and shall provide recommendations to adequately safeguard these PATIENTS and MR WORKERS from injury. For the MR WORKER and the PATIENT especially the RISK due to the past professional activity, which could have caused accidental implantation of ferromagnetic materials, shall be considered. The following specific classes of PATIENTS shall be mentioned: – classes of PATIENTS for whom MR EXAMINATIONS are considered to be contraindicated; – classes of PATIENTS having higher than normal likelihood of needing emergency medical treatment, independent of the physical environment of the MR EQUIPMENT; – classes of PATIENTS having a higher than normal likelihood of needing emergency medical treatment due to the elevated values of the applied fields, when the MR EQUIPMENT is capable of operating within the FIRST LEVEL CONTROLLED OPERATING MODE as described in subclause 201.12.4.101. * b) MEDICAL SUPERVISION OF PA
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