1、BRITISH STANDARD BS EN 61266:1995 IEC1266:1994 Ultrasonics Hand-held probe Doppler foetal heartbeat detectors Performance requirements and methods of measurement and reporting The European Standard EN61226:1995 has the status of a BritishStandardBSEN61266:1995 This British Standard, having been prep
2、ared under the directionof the ElectrotechnicalSector Board, was published under the authorityof the Standards Boardand comes into effect on 15October1995 BSI 02-2000 The following BSI references relate to the work on this standard: Committee reference EPL/87 Draft for comment 91/22890 DC ISBN 0 580
3、 24579 9 Committees responsible for this BritishStandard The preparation of this BritishStandard was entrusted to Technical Committee EPL/87, Ultrasonics, upon which the following bodies were represented: British Dental Association British Institute of Radiology British Medical Ultrasound Society Br
4、itish Society for Rheumatology Department of Health Department of Trade and Industry(National Physical Laboratory) Institute of Laryngology and Otology Institute of Physical Sciences in Medicine Institution of Electrical Engineers Amendments issued since publication Amd. No. Date CommentsBSEN61266:1
5、995 BSI 02-2000 i Contents Page Committees responsible Inside front cover National foreword ii Foreword 2 Text of EN61266 3 List of references Inside back coverBSEN61266:1995 ii BSI 02-2000 National foreword This BritishStandard has been prepared by EPL/87 and is the English language version of EN61
6、266:1995 Ultrasonics Hand-held probe Doppler foetal heartbeat detectors Performance requirements and methods of measurement and reporting, published by the European Committee for Electrotechnical Standardization(CENELEC). It is identical with IEC1226:1994, published by the International Electrotechn
7、ical Commission(IEC). 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 confer immunity from legal obligations. Cross-references Pu
8、blication referred to Corresponding BritishStandard EN60601-1:1990 (IEC601-1:1988) BS5724 Medical electrical equipment Part1:1989 General requirements for safety EN61101:1993 (IEC1101:1991) BS EN61101:1994 Specification for absolute calibration of hydrophones using the planar scanning technique in t
9、he frequency range0,5MHz to15MHz EN61102:1993 (IEC1102:1991) BS EN61102:1994 Specification for measurement and characterisation of ultrasonic fields using hydrophones in the frequency range0.5MHz to15MHz EN61157:1994 (IEC1157:1992) BS EN61157:1995 Requirements for the declaration of the acoustic out
10、put of medical diagnostic ultrasonic equipment EN61161:1994 (IEC1161:1992) BS EN61161:1995 Specification for ultrasonic power measurement in liquids in the frequency range0.5MHz to25MHz IEC866:1987 BS7041:1989 Specification for characteristics and calibration of hydrophones for operation in the freq
11、uency range0.5MHz to15MHz Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, theEN title page, pages2 to22, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be in
12、dicated in the amendment table on the inside front cover.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN61266 April1995 ICS11.040.50 Descriptors: Ultrasound, Doppler detector, foetus, performance, measurement English version Ultrasonics Hand-held probe Doppler foetal heartbeat detectors Perform
13、ance requirements and methods of measurement and reporting (IEC1266:1994) Ultrasons Dtecteurs des battements de coeur foetal effet Doppler avec sonde main Prescriptions de performance et mthodes de mesure et de signalement (CEI1266:1994) Ultraschall Handgehaltene Doppler-Herzschlag-detektoren fr Fte
14、n Leistungsanforderungen sowie Me- und Angabeverfahren (IEC1266:1994) This European Standard was approved by CENELEC on1995-02-15. 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 s
15、tandard 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 o
16、ther 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, Denmark, Finland, France, Germa
17、ny, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secr
18、etariat: rue de Stassart 35, B-1050 Brussels 1995 Copyright reserved to CENELEC members Ref. No. EN61266:1995 EEN61266:1995 BSI 02-2000 2 Foreword The text of document87(CO)34, future edition1 of IEC1266, prepared by IEC TC87, Ultrasonics, was submitted to the IEC-CENELEC parallel vote and was appro
19、ved by CENELEC as EN61266 on1995-02-15. The following dates were fixed: For products which have complied with the relevant national standard before1996-02-15, as shown by the manufacturer or by a certification body, this previous standard may continue to apply for production until2001-02-15. Annexes
20、 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, Annex D and Annex E are informative. Annex ZA has been added by CENELEC. Contents Page Foreword 2 Intr
21、oduction 3 1 Scope 3 2 Normative references 3 3 Definitions 4 4 List of symbols 5 5 Configuration 5 6 Performance 5 6.1 Acoustic working frequency 5 7 Safety 5 8 Tests 5 8.1 Acoustic working frequency 5 8.2 Output power 6 8.3 Spatial-peak temporal-peak acoustic pressure 6 8.4 Effective area of the u
22、ltrasonic transducer active element 6 8.5 Overall sensitivity 6 Page 9 Preferred method for reporting performance of existing equipment 8 10 Specifications for labelling 9 11 Sampling 9 Annex A (informative) Choice of target anddetermination of target plane-wave reflectionloss 12 Annex B (informativ
23、e) Typical test equipmentandtest procedures 17 Annex C (informative) Determination of the two-way insertion loss of acoustic attenuators 19 Annex D (informative) Rationale 20 Annex E (informative) Bibliography 20 Annex ZA (normative) Normative references tointernational publications with their corre
24、sponding European publications 21 Figure 1 Configuration block diagram of theequipment 9 Figure 2 Configuration block diagram for acoustic working frequency measurement 10 Figure 3 Block diagram illustrating the basicconcepts of the overall sensitivity test method 10 Figure 4 Sample point for determ
25、ining signallevel in relation to triangular excitation waveform for target 11 Figure A.1 Target plane-wave reflection lossatadistance of100mm for four types of targetas a function of frequency 15 Figure A.2 Three typical configurations forthedetermination of the plane-wave reflectionloss for a targe
26、t, a) and b) use hydrophones as detectors; c) uses the transducerforboth transmission and reception.Allconfigurations show the positionsofthe target and detector first for determining the reflected acoustic pressure andsecond for determining the incident acousticpressure 16 Figure B.1 Typical vessel
27、 for overall sensitivitytest 18 Table A.1 Details of steel ball reflectors 13 latest date by which the ENhas to be implemented at national level by publication of an identical national standard or by endorsement (dop)1996-02-15 latest date by which the national standards conflicting with the EN have
28、to be withdrawn (dow)1996-02-15EN61266:1995 BSI 02-2000 3 Introduction Hand-held ultrasonic Doppler foetal heartbeat detectors are widely used for monitoring foetal heartbeat during pregnancy. They normally operate at frequencies of circa2MHz, and consist of an ultrasonic transducer acoustically cou
29、pled to the maternal abdomen and associated electronics. A beam of ultrasound is directed by the operator to impinge on the foetal heart and a small fraction of the incident ultrasound is reflected from the moving surfaces of the heart. This ultrasound is subject to a frequency shift as a result of
30、the Doppler effect. It is then detected by a receiving transducer. Signal processing separates the low-frequency signals associated with the foetal heartbeat from the high-frequency ultrasonic oscillations and amplifies them for audio detection. This International Standard, IEC1266, specifies method
31、s of evaluating the performance of ultrasonic foetal heartbeat detectors and, in particular, specifies a method of determining the sensitivity of the system to the detection of a moving target. Foetal Doppler monitoring devices use a flat probe strapped to the patient and work on a principle similar
32、 to that of hand-held foetal heartbeat detectors but are not covered by this standard. The reason is that monitoring devices require a wide angle of view which is often realised by using a multi-element transducer. This makes the method of operation of foetal Doppler monitors much more complex than
33、that of hand-held foetal heartbeat detectors which use a narrow beam. Methods of assessment of performance would also be more complex. 1 Scope This International Standard IEC1266 establishes: methods of measurement of performance of a complete ultrasonic hand-held Doppler foetal heartbeat detector(h
34、ereinafter referred to as “equipment”); requirements for the performance of equipment; requirements for the reporting of the performance of existing equipment; requirements for the declaration by manufacturers in accompanying literature of aspects of the performance of equipment. This International
35、Standard is applicable to ultrasonic Doppler foetal heartbeat detectors which generate a single ultrasound beam and consist of a hand-held probe which is applied to the maternal abdomen to obtain information on foetal heart activity by means of the Doppler method using continuous wave(c.w.) or quasi
36、-continuous wave ultrasound. This standard, however, currently does not cover the continuous monitoring devices which generate more than one ultrasound beam and are usually of the type utilising a similar principle of operation but using a flat probe strapped to the patient. This International Stand
37、ard is not an equipment design standard. 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
38、 subject to revision, 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. IE
39、C601-1:1988, Medical electrical equipment Part1: General requirements for safety. IEC854:1986, Methods of measuring the performance of ultrasonic pulse-echo diagnostic equipment. IEC866:1987, Characteristics and calibration of hydrophones for operation in the frequency range0,5MHz to15MHz. IEC1101:1
40、991, The absolute calibration of hydrophones using the planar scanning technique in the frequency range0,5MHz to15MHz. IEC1102:1991, Measurement and characterisation of ultrasonic fields using hydrophones in the frequency range of0,5MHz to15MHz. IEC1157:1992, Requirements for the declaration of the
41、acoustic output of medical diagnostic ultrasonic equipment. IEC1161:1992, Ultrasonic power measurement in liquids in the frequency range0,5MHz to25MHz. EN61266:1995 4 BSI 02-2000 3 Definitions For the purposes of this International Standard, the following definitions apply: 3.1 acoustic coupling med
42、ium material placed between the probe and the body surface in order to maintain acoustic transmission 3.2 acoustic working frequency frequency of an acoustic signal based on the observation of the output of a hydrophone placed in an acoustic field for the purposes of this International Standard, the
43、 signal is analysed using the zero-crossing frequency technique, seeIEC854. 3.4.1 of IEC1102 3.3 continuous wave ultrasound ultrasonic oscillations which are either continuous or quasi-continuous lasting for many tens of cycles 3.4 doppler frequency change in frequency of an ultrasound scattered wav
44、e caused by relative motion between the scatterer and the probe. It is the difference frequency between the transmitted and the received wave 3.5 effective area of the ultrasonic transducer active element 6dB beam area at a distance of5mm from the face of the probe. 3.6 of IEC1102 Unit: millimetre s
45、quared, mm 2 3.6 doppler signal signal at the Doppler frequency 3.7 equipment ultrasonic Doppler foetal heartbeat detector 3.8 nominal acoustic working frequency value of the acoustic working frequency quoted by the designer or manufacturer 3.9 output power time-average ultrasonic power radiated by
46、an ultrasonic transducer into an approximately free field under specified conditions in a specified medium, preferably in water. 3.5 of IEC1161 3.10 overall sensitivity measure of the ability of an ultrasonic Doppler foetal heartbeat detector to detect, above the noise level, a Doppler signal from a
47、 simulated point target(less than three wavelengths wide) of known target plane-wave reflection loss, moving at a specified velocity and placed at a specified distance from the probe. The overall sensitivity level, S, in decibels(dB) is determined from: S = A(d)+B + C 3.11 probe an assembly, includi
48、ng the ultrasonic transducer element(s), which is dedicated to the transmission and reception of ultrasound energy. It may also include other components as necessary 3.12 receiver unit part of the equipment which processes the ultrasonic signals from the probe to produce at least a Doppler signal in
49、 the audible frequency range 3.13 signal output part part of the equipment not being an applied part, intended to deliver output signal voltages or currents to other equipment, for example, for display, recording or data processing. 2.1.19 of IEC601-1 NOTEFor an ultrasonic Doppler foetal heartbeat detector, the signal output part is usually a terminal or connector at the output of the receiver unit which allows connection of an earphone, headphone, speaker or other audio equipment. 3.14 spatial-peak temporal-peak acoustic pressure