1、BRITISH STANDARD BSEN 61846:1999 IEC61846: 1998 Ultrasonics Pressure pulse lithotripters Characteristics of fields The European Standard EN61846:1998 has the status of a BritishStandard ICS 11.040.60BSEN61846:1999 This British Standard, having been prepared under the directionof the Electrotechnical
2、 Sector Committee, was publishedunder the authority ofthe Standards Committee andcomes into effect on 15 January1999 BSI 05-1999 ISBN 0 580 29936 8 National foreword This British Standard is the English language version of EN61846:1998. It is identical with IEC61846:1998. The UK participation in its
3、 preparation was entrusted to Technical Committee EPL/87, Ultrasonics, which has the responsibility to: aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed;
4、monitor related international and European developments and promulgate them in the UK. A list of organizations represented on this committee can be obtained on request to its secretary. From1January1997, all IEC publications have the number60000added to the old number. For instance, IEC27-1has been
5、renumbered as IEC60027-1. For a period of time during the change over from one numbering system to the other, publications may contain identifiers from both systems. Cross-references Attention is drawn to the fact that CEN and CENELEC standards normally include an annex which lists normative referen
6、ces to international publications with their corresponding European publications. The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence I
7、ndex”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself
8、 confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, theEN title page, pages2to19and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated i
9、n the amendment table on the inside front cover. Amendments issued since publication Amd. No. Date CommentsBSEN61846:1999 BSI 05-1999 i Contents Page National foreword Inside front cover Foreword 2 Text of EN61846 3ii blankEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 61846 August 1998 ICS11.
10、040.50 Descriptors: English version Ultrasonics Pressure pulse lithotripters Characteristics of fields (IEC61846:1998) Ultrasons Lithotripteurs ondes de pression Caractrisation des champs (CEI61846:1998) Ultraschall Druckpuls-Lithotripter Feldcharakterisierung (IEC61846:1998) This European Standard
11、was approved by CENELEC on1998-04-01. 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 su
12、ch 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
13、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, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portug
14、al, Spain, Sweden, Switzerland and United Kingdom. CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B-1050 Brussels 1998 Copyright reserved to CENE
15、LEC members Ref. No. EN61846:1998EEN61846:1998 BSI 05-1999 2 Foreword The text of document87/115/FDIS, future edition1of IEC61846, prepared by IECTC87, Ultrasonics, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN61846 on1998-04-01. The following dates were fixed: Ann
16、exes designated “normative” are part of the body of the standard. Annexes designated “informative” are given for information only. In this standard, Annex ZA is normative and Annex A, Annex B, Annex C and Annex D are informative. Annex ZA has been added by CENELEC. Endorsement notice The text of the
17、 International Standard IEC61846:1998 was approved by CENELEC as a European Standard without any modification. Contents Page Foreword 2 Introduction 3 1 Scope 3 2 Normative references 3 3 Definitions 3 4 List of symbols 7 5 Conditions of measurement 7 6 Test equipment 7 6.1 Test chamber 7 6.2 Hydrop
18、hone 8 6.3 Voltage measurement 8 7 Measurement procedure 9 7.1 Spatial measurements 9 7.2 Temporal measurements 10 7.3 Acoustic energy measurements 10 Annex A (informative) Acoustic wave lithotripsy 12 Annex B (informative) Types of pressure wave transducers 12 Annex C (informative) Field measuremen
19、t 14 Annex D (informative) Bibliography 18 Annex ZA (normative) Normative references to international publications with their corresponding European publications 19 Figure C.1 Typical pressure pulse waveform at the focus 17 Figure C.2 Typical spatial pressure distribution at the focus (upper plot) a
20、nd the derived pulse-intensity integral (lower plot) 18 Table C.1 Hydrophones possible for focus and field measurements 15 Table C.2 Measurement techniques and probes for quality assurance purposes 15 latest date by which the EN has to be implemented at national level by publication of an identical
21、national standard or by endorsement (dop)1999-01-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow)2001-01-01EN61846:1998 BSI 05-1999 3 Introduction Extracorporeal lithotripsy is used for the clinical treatment of renal, ureteric and biliary stones. Lit
22、hotripsy employs high-intensity acoustic waves to produce disintegration of the stones through a process of sequential application of pressure waves. Several different forms of lithotripsy equipment are now commercially available from a number of manufacturers. This International Standard specifies
23、methods of measuring and characterizing the acoustic pressure field generated by lithotripsy equipment. 1 Scope This International Standard is applicable to lithotripsy equipment using extracorporeally induced pressure waves; lithotripsy equipment producing focused mechanical energy. This Internatio
24、nal Standard does not apply to percutaneous and laser lithotripsy equipment. This International Standard specifies measurable parameters which could be used in the declaration of the acoustic output of extracorporeal lithotripsy equipment, methods of measurement and characterization of the pressure
25、field generated by lithotripsy equipment. NOTEThe parameters defined in this International Standard do not at the present time allow quantitative statements to be made about effectiveness and possible hazard. In particular, it is not possible to make a statement about the limits for these effects. W
26、hile this particular standard has been developed for equipment intended for use in lithotripsy, it has been developed such that, as long as no other specific standards are available to be used for other medical applications of therapeutic extracorporeal pressure pulse equipment, this standard may be
27、 used as a guideline. 2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the editions indicated were valid. All normative documents are subject to revisio
28、n, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. IEC60050(801):1994, I
29、nternational Electrotechnical Vocabulary (IEV) Chapter801:Acoustics and electroacoustics. IEC60866:1987, Characteristics and calibration of hydrophones for operation in the frequency range0,5MHz to15MHz. IEC61102:1991, Measurement and characterisation of ultrasonic fields using hydrophones in the fr
30、equency range0,5MHz to15MHz. 3 Definitions For the purpose of this International Standard, the following definitions apply. 3.1 acoustic pulse energy 3.1.1 derived acoustic pulse energy spatial integral of the derived pulse-intensity integral over a circular cross-sectional area of radius R in the x
31、-y plane which contains the focus Symbol: E R Unit: joule, J 3.1.2 derived focal acoustic pulse energy spatial integral of the derived pulse-intensity integral over the focal cross-sectional areaEN61846:1998 4 BSI 05-1999 Symbol: E f Unit: joule, J NOTEThis definition may overestimate E if the apert
32、ure of the pressure pulse generator is large. 3.2 beam axis line passing through the geometric centre of the aperture of the pressure pulse generator and the focus NOTEThis line is taken as the z axis. See6.1 and clause7. 3.3 compressional pulse duration time interval beginning at the first time the
33、 instantaneous acoustic pressure exceeds50% of the peak-positive acoustic pressure and ending at the next time the instantaneous acoustic pressure has that value (see Figure C.1) Symbol: t FWHMp+ Unit: second, s NOTEThe subscript “FWHM” stands for “full width, half maximum”. 3.4 derived pulse-intens
34、ity integral time integral of the instantaneous intensity at a particular point in a pressure pulse field over the pressure pulse waveform (see3.31 of IEC61102) Symbol: PII Unit: joule per metre squared, J/m 2 3.5 end-of-cable loaded sensitivity of a hydrophone ratio of the voltage at the end of any
35、 integral cable or connector of a hydrophone, when connected to a specified electrical input impedance, to the instantaneous acoustic pressure in the undisturbed free field of a plane wave in the position of the acoustic centre of the hydrophone if the hydrophone were removed (see3.14 of IEC61102) S
36、ymbol: M L Unit: volt per pascal, V Pa 1 3.6 focal cross-sectional area area of the peak-compressional acoustic pressure contour which is6dB relative to the value at the focus and is in the plane, perpendicular to the beam axis, which contains the focus Symbol: A f Unit: metre squared, m 2 3.7 focal
37、 extent shortest distance along the z axis that connects points on the6dB contour of peak-positive acoustic pressure in the x-z plane on either side of the focus Symbol: f z Unit: metre, m 3.8 focal volume volume in space contained within the surface defined by the6dB (relative to the value at the f
38、ocus) peak-compressional acoustic pressure contours measured around the focus Symbol: V f Unit: metre cubed, m 3 NOTEIt is difficult to measure 6dB points throughout the volume around the focus. It is reasonable in practice to approximate the focal volume from measurements taken in three orthogonal
39、directions: the beam axis (z axis); the direction of maximum beam diameter (x axis); the axis perpendicular to the x axis (y axis).EN61846:1998 BSI 05-1999 5 3.9 focal width, maximum maximum width of the6dB contour of p +around the focus in the. x-y plane which contains the focus Symbol: f x Unit: m
40、etre, m 3.10 focal width, orthogonal width of the6dB contour of p +around the focus, in the x-y plane which contains the focus, in the direction perpendicular to f x Symbol: f y Unit: metre, m 3.11 focus location in the pressure pulse field of the maximum peak-positive acoustic pressure 3.12 hydroph
41、one transducer that produces electrical signals in response to waterborne acoustic signals IEV 801-32-26 (see also IEC60866) 3.13 instantaneous acoustic pressure pressure minus the ambient pressure at a particular instant in time and at a particular point in an acoustic field see also801-21-19 of IE
42、C60050(801) Symbol: p Unit: pascal, Pa 3.14 instantaneous intensity acoustic energy transmitted per unit time in the direction of acoustic wave propagation per unit area normal to this direction at a particular instant in time and at a particular point in an acoustic field for measurement purposes r
43、eferred to in this standard, where far-field conditions may be assumed, the instantaneous intensity, I, is expressed as: where (See also3.21 of IEC 61102.) Symbol: I Unit: watt per metre squared, W/m 2 3.15 lithotripsy equipment device for disintegrating calculi and other concretions within the body
44、 NOTEKnown applications include renal stones, gallstones, pancreatic duct stones, salivary stones, orthopaedic pain and calcification in tendons. p is the instantaneous acoustic pressure; Z is the characteristic acoustic impedance of the medium. I P 2 Z - =EN61846:1998 6 BSI 05-1999 3.16 peak-negati
45、ve acoustic pressure, peak-rarefactional acoustic pressure maximum of the modulus of the rarefactional acoustic pressure at any spatial location in the pressure pulse field (see3.26 of IEC61102) Symbol: p Unit: pascal, Pa 3.17 peak-positive acoustic pressure, peak-compressional acoustic pressure max
46、imum compressional acoustic pressure at any spatial location in the pressure pulse field (see3.27 of IEC61102) Symbol: p + Unit: pascal, Pa 3.18 pressure pulse acoustic wave emitted by the lithotripsy equipment 3.19 pressure pulse waveform temporal waveform of the instantaneous acoustic pressure at
47、a specified position in a pressure pulse field and displayed over a period sufficiently long to include all significant acoustic information in the pressure pulse 3.20 pulse-pressure-squared integral time integral of the square of the instantaneous acoustic pressure over the pressure pulse waveform
48、Symbol: P i Unit: pascal squared seconds 3.21 rise time at the focus, time taken for the instantaneous acoustic pressure to increase from10% to90% of the peak-positive acoustic pressure (see Figure C.1) Symbol: t r Unit: second, s 3.22 target location location in space where the manufacturer intends
49、 the user to locate the calculi 3.23 temporal integration limits 3.23.1 positive temporal integration limits times between which the positive acoustic pressure first exceeds10% of its maximum value and the first time it reduces below10% of its maximum value Symbol: T p Unit: seconds 3.23.2 total temporal integration limits times between which the absolute value (modulus) of pressure pulse waveform first exceeds10% of its maximum value and the last time it reduces below10% of its maximum value Symbol: T T Unit: secon
