1、 IEC/TR 62799 Edition 1.0 2013-09 TECHNICAL REPORT Models for evaluation of thermal hazard in medical diagnostic ultrasonic fields IEC/TR 62799:2013(E)Copyrighted material licensed to BR Demo by Thomson Reuters(Scientific),Inc.,downloaded on Nov-27-2014 by James Madison.No further reproduction or di
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9、stomer Service Centre:csciec.ch.Copyrighted material licensed to BR Demo by Thomson Reuters(Scientific),Inc.,downloaded on Nov-27-2014 by James Madison.No further reproduction or distribution is permitted.Uncontrolled when printed.IEC/TR 62799 Edition 1.0 2013-09 TECHNICAL REPORT Models for evaluati
10、on of thermal hazard in medical diagnostic ultrasonic fields INTERNATIONAL ELECTROTECHNICAL COMMISSION X ICS 11.040.50 PRICE CODE ISBN 978-2-8322-1099-4 Registered trademark of the International Electrotechnical Commission Warning!Make sure that you obtained this publication from an authorized distr
11、ibutor.Copyrighted material licensed to BR Demo by Thomson Reuters(Scientific),Inc.,downloaded on Nov-27-2014 by James Madison.No further reproduction or distribution is permitted.Uncontrolled when printed.2 TR 62799 IEC:2013(E)CONTENTS FOREWORD.4 1 Scope.6 2 Normative references.6 3 Terms and defin
12、itions.6 4 Background.10 4.1 General.10 4.2 Limitations of the existing standard.11 4.2.1 Linear display.11 4.2.2 Equilibrium temperature.12 4.2.3 Tissue parameters.12 4.2.4 Transducer self-heating.12 4.2.5 Safety limits.12 5 Options for improvement of the existing standard.13 5.1 General.13 5.2 Exp
13、onential display of the current TI.13 5.2.1 Theory.13 5.2.2 Illustrative results for the new thermal index display.15 5.2.3 Advantages of the new display.15 5.2.4 Shortcomings of the new display.16 5.3 Replacement of the TI with the thermally equivalent time index(TETI).16 5.3.1 Theory.16 5.3.2 Illu
14、strative results for the TETI.20 5.3.3 Advantages of the TETI.22 5.3.4 Shortcomings of the TETI.22 5.4 Replacement of the TI with the time to threshold(TT).23 5.4.1 Theory.23 5.4.2 Illustrative results for the TT.24 5.4.3 Advantages of the TT.27 5.4.4 Shortcomings of the TT.27 5.5 Replacement of the
15、 TI with the safe use time(SUT).28 5.5.1 Theory.28 5.5.2 Illustrative results for the SUT.30 5.5.3 Advantages of the SUT.33 5.5.4 Shortcomings of the SUT.33 5.6 Replacement of the TI with the thermally equivalent time displayed(TETD).34 5.6.1 Theory.34 5.6.2 Illustrative results for the TETD.35 5.6.
16、3 Advantages of the TETD.38 5.6.4 Shortcomings of the TETD.39 6 Summary.40 7 Recommendations.41 7.1 General.41 7.2 Thermally equivalent time index.41 7.3 Other models.41 Bibliography.42 Copyrighted material licensed to BR Demo by Thomson Reuters(Scientific),Inc.,downloaded on Nov-27-2014 by James Madison.No further reproduction or distribution is permitted.Uncontrolled when printed.TR 62799 IEC:2013(E)3 Figure 1 Comparison of the values of thermal index that would be displayed under the prop