SIST EN 60613:2010

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.UDYQLãNHElektrische und Belastungs-Kennwerte von Röntgenstrahlern für die medizinische Diagnostik (IEC 60613:2010)Caractéristiques électriques et de charge des gaines équipées pour diagnostic médical (CEI 60613:2010)Electrical and loading characteristics of X-ray tube assemblies for medical diagnosis (IEC 60613:2010)11.040.50Radiografska opremaRadiographic equipmentICS:Ta slovenski standard je istoveten z:EN 60613:2010SIST EN 60613:2010en,fr01-junij-2010SIST EN 60613:2010SLOVENSKI
STANDARDSIST EN 60613:19951DGRPHãþD



SIST EN 60613:2010



EUROPEAN STANDARD EN 60613 NORME EUROPÉENNE
EUROPÄISCHE NORM April 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 60613:2010 E
ICS 11.040.50 Supersedes EN 60613:1990
English version
Electrical and loading characteristics of X-ray tube assemblies
for medical diagnosis (IEC 60613:2010)
Caractéristiques électriques et de charge des gaines équipées pour diagnostic médical (CEI 60613:2010)
Elektrische und Belastungs-Kennwerte von Röntgenstrahlern für die medizinische Diagnostik (IEC 60613:2010)
This European Standard was approved by CENELEC on 2010-04-01. 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.
SIST EN 60613:2010



EN 60613:2010 - 2 - Foreword The text of document 62B/774/FDIS, future edition 3 of IEC 60613, 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 60613 on 2010-04-01. This standard supersedes EN 60613:1990. It constitutes a technical revision. EN 60613:2010 has been adapted to apply to the present technology. 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)
2011-01-01 – latest date by which the national standards conflicting
with the EN have to be withdrawn
(dow)
2013-04-01 Annex ZA has been added by CENELEC. __________ Endorsement notice The text of the International Standard IEC 60613:2010 was approved by CENELEC as a European Standard without any modification. __________ SIST EN 60613:2010



- 3 - EN 60613:2010 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.
Publication Year Title EN/HD Year
IEC 60601-1 2005 Medical electrical equipment -
Part 1: General requirements for basic safety and essential performance EN 60601-1 2006
IEC 60601-1-3 2008 Medical electrical equipment -
Part 1-3: General requirements for basic safety and essential performance - Collateral Standard: Radiation protection in diagnostic X-ray equipment EN 60601-1-3 2008
IEC/TR 60788 2004 Medical electrical equipment - Glossary of defined terms - -
SIST EN 60613:2010



SIST EN 60613:2010



IEC 60613Edition 3.0 2010-01INTERNATIONAL STANDARD NORME INTERNATIONALEElectrical and loading characteristics of X-ray tube assemblies for medical diagnosis
Caractéristiques électriques et de charge des gaines équipées pour diagnostic médical
INTERNATIONAL ELECTROTECHNICAL COMMISSION COMMISSION ELECTROTECHNIQUE INTERNATIONALE SICS 11.040.50 PRICE CODECODE PRIXISBN 2-8318-1077-9
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale ® SIST EN 60613:2010 colourinside



– 2 – 60613 © IEC:2010 CONTENTS FOREWORD.3 1 Scope.5 2 Normative references.5 3 Terms and definitions.5 4 Presentation of the electrical characteristic.8 4.1 X-RAY TUBE VOLTAGE.8 4.2 NOMINAL X-RAY TUBE VOLTAGE.8 4.3 X-RAY TUBE CURRENT.8 4.4 CATHODE EMISSION CHARACTERISTIC.8 4.5 ENVELOPE characteristics.9 4.5.1 ENVELOPE CURRENT.9 4.5.2 ENVELOPE VOLTAGE.9 5 LOADING of an X-RAY TUBE.9 5.1 LOADING TIME.9 5.1.1 Units.9 5.1.2 Measurement.9 5.2 CYCLE TIME.9 6 Input power.9 6.1 ANODE INPUT POWER.9 6.2 NOMINAL ANODE INPUT POWER.9 6.3 NOMINAL RADIOGRAPHIC ANODE INPUT POWER.10 6.4 NOMINAL CT ANODE INPUT POWER.10 6.5 X-RAY TUBE ASSEMBLY INPUT POWER.10 6.6 NOMINAL CONTINUOUS INPUT POWER.10 6.7 CONTINUOUS ANODE INPUT POWER.10 6.8 CT SCAN POWER INDEX (CTSPI).10 6.9 NOMINAL CT SCAN POWER INDEX (NOMINAL CTSPI).10 7 RADIOGRAPHIC RATINGS.10 7.1 General.10 7.2 SINGLE LOAD RATING.10 7.3 SERIAL LOAD RATING.10 8 Presentation of data.11 Annex A (informative)
Rationale and historical background.12 Annex B (informative)
Measurement of the X-RAY TUBE CURRENT.17 Bibliography.18 Index of defined terms.19
Figure A.1 – Example: SINGLE LOAD RATING chart showing CTSPI calculation area for scan time interval of 1 s to 25 s.14 Figure A.2 – Example: SINGLE LOAD RATING curves for two different CT tubes, both having the same value of NOMINAL CT ANODE INPUT POWER.15 Figure B.1 – Electrical schematic of X-RAY TUBE CURRENT measurement.17
SIST EN 60613:2010



60613 © IEC:2010 – 3 – INTERNATIONAL ELECTROTECHNICAL COMMISSION ____________
ELECTRICAL AND LOADING CHARACTERISTICS
OF X-RAY TUBE ASSEMBLIES 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 60613 has been prepared by subcommittee 62B: Diagnostic imaging equipment, of IEC technical committee TC 62: Electrical equipment in medical practice. This third edition cancels and replaces the second edition of IEC 60613, published in 1989. It constitutes a technical revision. This third edition has been adapted to apply to the present technology. The text of this standard is based on the following documents: FDIS Report on voting 62B/774/FDIS 62B/780/RVD
Full information on the voting for the approval of this 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. SIST EN 60613:2010



– 4 – 60613 © IEC:2010 In this standard, the following print types are used: – requirements and definitions: roman 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 THIS STANDARD OR AS NOTED: SMALL CAPS. The committee has decided that the contents of this publication will remain unchanged until the maintenance result 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.
SIST EN 60613:2010



60613 © IEC:2010 – 5 – ELECTRICAL AND LOADING CHARACTERISTICS
OF X-RAY TUBE ASSEMBLIES FOR MEDICAL DIAGNOSIS
1 Scope
This International Standard applies to X-RAY TUBE ASSEMBLIES either with a rotating ANODE X-RAY TUBE or a stationary ANODE X-RAY TUBE, intended for use in medical diagnosis. For an X-RAY TUBE HEAD, its X-RAY TUBE ASSEMBLY aspects are also within the scope. This International Standard covers performance-related definitions and conditions of electrical and LOADING characteristics of X-RAY TUBE ASSEMBLIES in relation to their behaviour during and after energization and, where appropriate, methods of presentation and measurement of these characteristics. This International Standard is therefore relevant for the MANUFACTURER and the RESPONSIBLE ORGANIZATION. NOTE “Measurement" in this standard is always related to practical use. Consequently, “measurement" is meant to consume only a negligible part of the life of the X-RAY TUBE ASSEMBLY. 2 Normative references 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. IEC 60601-1:2005, Medical electrical equipment – Part 1: General requirements for basic safety and essential performance IEC 60601-1-3:2008, Medical electrical equipment – Part 1-3: General requirements for basic safety and essential performance – Collateral Standard: Radiation protection in diagnostic X-ray equipment IEC/TR 60788:2004, Medical electrical equipment – Glossary of defined terms (available only in English) 3 Terms and definitions For the purposes of this document, the terms and definitions given in IEC/TR 60788:2004, IEC 60601-1:2005 and IEC 60601-1-3:2008 and the following apply. 3.1
X-RAY TUBE VOLTAGE potential difference applied to an X-RAY TUBE between the ANODE and the CATHODE. Usually X-RAY TUBE VOLTAGE is expressed by its peak value in kilovolts (kV) [IEC 60601-1-3:2008, 3.88] 3.2
NOMINAL X-RAY TUBE VOLTAGE highest permitted X-RAY TUBE VOLTAGE for SPECIFIC operating conditions [IEC 60601-1-3:2008, 3.42] SIST EN 60613:2010



– 6 – 60613 © IEC:2010 NOTE 1 For different operating conditions of the X-RAY TUBE, for example continuous operation, intermittent operation, short-time operation, different types of X-RAY TUBE HOUSINGS, there may be different values of the above NOMINAL X-RAY TUBE VOLTAGE. NOTE 2 Additionally, values may be given for the highest permitted potential difference between ANODE and earth and between CATHODE and earth. 3.3
X-RAY TUBE CURRENT electric current of the ELECTRON beam incident on the TARGET of an X-RAY TUBE. Usually, the X-RAY TUBE CURRENT is expressed by its mean value in milliamperes (mA) [IEC 60601-1-3:2008, 3.85] NOTE See Annex B for further considerations. 3.4
CATHODE EMISSION CHARACTERISTIC dependence of the X-RAY TUBE CURRENT on variables, for example FILAMENT CURRENT, X-RAY TUBE VOLTAGE 3.5
ENVELOPE vacuum-wall of the X-RAY TUBE 3.6
ENVELOPE CURRENT electric current, flowing via a conducting part of an ENVELOPE 3.7
ENVELOPE VOLTAGE potential difference between an X-RAY TUBE-conducting ENVELOPE part and earth 3.8
LOADING in an X-RAY GENERATOR, act of supplying electrical energy to the ANODE of an X-RAY TUBE [IEC 60601-1-3:2008, 3.34] 3.9
X-RAY TUBE LOAD electrical energy supplied to an X-RAY TUBE expressed by a combination of values of LOADING FACTORS 3.10
LOADING FACTOR factor influencing by its value the X-RAY TUBE LOAD, for example X-RAY TUBE CURRENT, LOADING TIME, CONTINUOUS ANODE INPUT POWER, X-RAY TUBE VOLTAGE and PERCENTAGE RIPPLE [IEC 60601-1-3:2008, 3.35] 3.11
LOADING TIME time determined according to a SPECIFIC method, during which the ANODE INPUT POWER is applied to the X-RAY TUBE [IEC 60601-1-3:2008, 3.37] SIST EN 60613:2010



60613 © IEC:2010 – 7 – 3.12
CYCLE TIME for a series of single LOADINGS: time interval from the beginning of a LOADING to the beginning of the next, identical LOADING for a series of serial LOADINGS: time interval from the beginning of a serial LOADING to the beginning of the next, identical serial LOADING 3.13
ANODE INPUT POWER power applied to the ANODE of an X-RAY TUBE to produce X-RADIATION 3.14
NOMINAL ANODE INPUT POWER highest constant ANODE INPUT POWER that can be applied for a single X-RAY TUBE LOAD in a SPECIFIC LOADING TIME and under SPECIFIED conditions 3.15
NOMINAL RADIOGRAPHIC ANODE INPUT POWER NOMINAL ANODE INPUT POWER which can be applied for a single X-RAY TUBE LOAD with a LOADING TIME of 0,1 s and a CYCLE TIME of 1,0 min, for an indefinite number of cycles NOTE 1 In this application, RADIOSCOPY is not applied. NOTE 2 With this definition mammographic and dental X-ray are included, see A.3.3 in Annex A. 3.16
NOMINAL CT ANODE INPUT POWER NOMINAL ANODE INPUT POWER which can be applied for a single X-RAY TUBE LOAD with a LOADING TIME of 4 s and a CYCLE TIME of 10 min, for an indefinite number of cycles 3.17
X-RAY TUBE ASSEMBLY INPUT POWER mean power applied to an X-RAY TUBE ASSEMBLY for all purposes before, during and after LOADING, including power applied to the stator of a rotating ANODE X-RAY TUBE, to the filament and to any other device included in the X-RAY TUBE ASSEMBLY 3.18
NOMINAL CONTINUOUS INPUT POWER SPECIFIED highest X-RAY TUBE ASSEMBLY INPUT POWER, which can be applied to an X-RAY TUBE ASSEMBLY continuously 3.19
CONTINUOUS ANODE INPUT POWER SPECIFIED highest ANODE INPUT POWER, which can be applied to the ANODE continuously NOTE 1 CONTINUOUS ANODE INPUT POWER may be determined by subtracting all power other than the ELECTRON beam power, such as filament heating, ANODE drive, from the NOMINAL CONTINUOUS INPUT POWER. NOTE 2 If not SPECIFIED otherwise, CONTINUOUS ANODE INPUT POWER is the referenced LOADING FACTOR for determining the LEAKAGE RADIATION. 3.20
CT SCAN POWER INDEX
CTSPI characteristic of an X-RAY TUBE ASSEMBLY intended for use in COMPUTED TOMOGRAPHY for a SPECIFIED range of LOADING TIMES for single LOADINGS, for a given CYCLE TIME, as follows ()ttd)(1 minmaxmaxmin
∫−=ttPttCTSPI SIST EN 60613:2010



– 8 – 60613 © IEC:2010 where tmax is the upper limit of the LOADING TIME in seconds, tmin is the lower limit of the LOADING TIME in seconds, and P(t) is the function representing the SINGLE LOAD RATING in kilowatts NOTE The CTSPI represents the effective power for PATIENT throughput in CT scanning. 3.21
NOMINAL CT SCAN POWER INDEX NOMINAL CTSPI CTSPI, calculated for a lower limit of the LOADING TIME of 1 s, an upper of the LOADING TIME of 25 s and a CYCLE TIME of 10 min 3.22
RADIOGRAPHIC RATINGS for the operation of an X-RAY TUBE, SPECIFIED combinations of conditions and LOADING FACTORS, under which the SPECIFIED limits of loadability of the X-RAY TUBE are attained 3.23
SINGLE LOAD RATING highest permitted X-RAY TUBE LOAD given by a relationship between constant ANODE INPUT POWER and LOADING TIME for one LOADING under SPECIFIED conditions 3.24
SERIAL LOAD RATING highest permitted X-RAY TUBE LOAD given by the relationship between ANODE INPUT POWER and LOADING TIME for the total of a SPECIFIED series of individual X-RAY TUBE LOADS with SPECIFIED LOADING FACTORS under SPECIFIED conditions 4 Presentation of the electrical characteristic 4.1 X-RAY TUBE VOLTAGE The X-RAY TUBE VOLTAGE shall be given as the peak value, in kilovolts. 4.2 NOMINAL X-RAY TUBE VOLTAGE The NOMINAL X-RAY TUBE VOLTAGE shall be given as the peak value, in kilovolts. 4.3 X-RAY TUBE CURRENT The X-RAY TUBE CURRENT shall be given as the average value in milliamperes. 4.4 CATHODE EMISSION CHARACTERISTIC CATHODE EMISSION CHARACTERISTICS are given as a family of curves in which the X-RAY TUBE CURRENT is shown as a function of the FILAMENT CURRENT and, if appropriate, of further characteristics of the CATHODE, each curve corresponding to an X-RAY TUBE VOLTAGE while specifying its waveform, and other factors as appropriate. If appropriate, the relationship between FILAMENT CURRENT and filament voltage shall be indicated and also its dependence on other characteristics of the CATHODE. SIST EN 60613:2010



60613 © IEC:2010 – 9 – 4.5 ENVELOPE characteristics 4.5.1 ENVELOPE CURRENT If the ENVELOPE CURRENT is to be stated, it shall be given as the percentage value of X-RAY TUBE CURRENT under SPECIFIED conditions. 4.5.2 ENVELOPE VOLTAGE If the ENVELOPE VOLTAGE is to be stated, it shall be given in kilovolts with respect to earth. 5 LOADING of an X-RAY TUBE 5.1 LOADING TIME 5.1.1 Units The LOADING TIME shall be given in seconds. 5.1.2 Measurement LOADING TIME is measured as the time interval between: – the instant that the X-RAY TUBE VOLTAGE has risen for the first time to a value of 75 % of the peak value; and
– the instant at which it finally drops below the same value. If LOADING is controlled by electronic switching of the HIGH VOLTAGE, using a grid in an electronic tube or in the X-RAY TUBE, the LOADING TIME may be determined as the time interval between the instant when the TIMING DEVICE generates the signal to start the IRRADIATION and the instant when it generates the signal to terminate the IRRADIATION. If LOADING is controlled by simultaneous switching in the primaries of both the high-voltage circuit and the heating supply for the filament of the X-RAY TUBE, the LOADING TIME shall be determined as the time interval between the instant when the X-RAY TUBE CURRENT first rises above 25 % of its maximum value and the instant when it finally falls below the same value. NOTE 1 See also definition 3.11. NOTE 2 The LOADING TIME is preferably measured at the tube input to minimise the influence of HV-cable-capacitance. NOTE 3 For field-testing, a reasonable approximation of the LOADING TIME can be obtained by measuring the IRRADIATION TIME, for which the SPECIFIC method according to the definition in IEC 60601-1-3:2008 is chosen in this International Standard as the time period during which the AIR KERMA RATE exceeds 50 % of its peak value. 5.2 CYCLE TIME The CYCLE TIME shall be given in minutes or seconds, as appropriate. 6 Input power 6.1 ANODE INPUT POWER The ANODE INPUT POWER shall be given in kilowatts for SPECIFIED conditions of LOADING. 6.2 NOMINAL ANODE INPUT POWER The NOMINAL ANODE INPUT POWER shall be given in kilowatts. SIST EN 60613:2010



– 10 – 60613 © IEC:2010 6.3 NOMINAL RADIOGRAPHIC ANODE INPUT POWER The NOMINAL RADIOGRAPHIC ANODE INPUT POWER shall be given in kilowatts. 6.4 NOMINAL CT ANODE INPUT POWER The NOMINAL CT ANODE INPUT POWER shall be given in kilowatts. 6.5 X-RAY TUBE ASSEMBLY INPUT POWER The X-RAY TUBE ASSEMBLY INPUT POWER shall be given in watts. 6.6 NOMINAL CONTINUOUS INPUT POWER The NOMINAL CONTINUOUS INPUT POWER shall be given in watts. Unless otherwise SPECIFIED, the ambient temperature shall be between 20 °C and 25 °C. 6.7 CONTINUOUS ANODE INPUT POWER The CONTINUOUS ANODE INPUT POWER shall be given in watts. 6.8 CT SCAN POWER INDEX (CTSPI) The CT SCAN POWER INDEX shall be given in kilowatts. 6.9 NOMINAL CT SCAN POWER INDEX (NOMINAL CTSPI) The NOMINAL CT SCAN POWER INDEX shall be given in kilowatts. 7 RADIOGRAPHIC RATINGS 7.1 General RADIOGRAPHIC RATINGS shall provide application-relevant parametric information on LOADING FACTORS, in any form of presentation (tables, graphs .) which is supporting the application. If a NOMINAL ANODE INPUT POWER is SPECIFIED, the RADIOGRAPHIC RATINGS shall at least encompass the set of LOADING FACTORS pertinent to the SPECIFIED NOMINAL ANODE INPUT POWER. 7.2 SINGLE LOAD RATING The SINGLE LOAD RATING shall be presented as curves or as a table of numerical values showing constant ANODE INPUT POWER as a function of LOADING TIME and CYCLE TIME for appropriate LOADING FACTORS, for example NOMINAL FOCAL SPOT VALUE, ANODE SPEED and others. 7.3 SERIAL LOAD RATING SERIAL LOAD RATINGS shall be presented as curves or as a table of numerical values with values of the CYCLE TIME and the appropriate LOADING FACTORS, for example, ANODE INPUT POWER for an individual X-RAY TUBE LOAD, LOADING TIME of an individual X-RAY TUBE LOAD, total number of LOADINGS or the duration of a series of LOADINGS, number of individual X-RAY TUBE LOADS per second. SIST EN 60613:2010



60613 © IEC:2010 – 11 – 8 Presentation of data If single data values are presented in compliance with this International Standard, such values shall be designated as follows: IEC 60613:2010 If graphs or tables are presented in compliance with this International Standard, a reference to IEC 60613:2010 shall be given. SIST EN 60613:2010



– 12 – 60613 © IEC:2010 Annex A
(informative)
Rationale and historical background
A.1 Overview The purpose of this annex is to state the general objectives and approach used in creating the 3rd edition of this standard, and to clarify the inclusion of those items which are substantially new to this edition, as well as to clarify why some items are no longer described. A.2 History: basis of 1st and 2nd editions The subject matter of these earlier editions was the electrical and thermal ratings of medical X-RAY TUBE ASSEMBLIES and their LOADING characteristics. Therefore, the thermal/electrical construction and operating mechanisms of X-RAY TUBES existing at the time of the earlier editions of the standard had a significant impact on the content of those early versions. Historically, medical X-RAY TUBES have been primarily constructed with glass ENVELOPES which act as the insulating support between the electrically charged ANODE and CATHODE electrodes. As such, it was not necessary or practical to define the electrical potential of this insulating ENVELOPE, which takes on an ambiguous charge state at any particular point of its surface. It was sufficient to state the potential difference between the ANODE and the CATHODE, or the potential of these electrodes relative to earth. Regarding the thermal/LOADING characteristics, most medical rotating ANODE X-RAY TUBES were constructed in such a way as to temporarily store the heat generated in the bremsstrahlung process and then dissipate it through the very non-linear thermal RADIATION process. Further, at the time of the earlier editions, applications were primarily directed at RADIOGRAPHY. In the meantime, vascular and CT applications, implying different LOADING conditions (relatively long exposures, heavy PATIENT throughput) have to be considered. A.3 Problems and solutions: objectives of the 3rd edition A.3.1 General Technical advancements in X-RAY TUBE design have lead to improvements, particularly in the thermal operation of X-RAY TUBES that have made the application of the previous edition of the standard inadequate. The main advancements and their impacts on the application of the sta
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