BS EN 61689:2013
$198.66
Ultrasonics. Physiotherapy systems. Field specifications and methods of measurement in the frequency range 0,5 MHz to 5 MHz
| Published By | Publication Date | Number of Pages |
| BSI | 2013 | 66 |
IEC 61689:2013 is applicable to ultrasonic equipment designed for physiotherapy containing an ultrasonic transducer generating continuous or quasi-continuous wave ultrasound in the frequency range 0,5 MHz to 5 MHz. This standard only relates to ultrasonic physiotherapy equipment employing a single plane non-focusing circular transducer per treatment head, producing static beams perpendicular to the face of the treatment head. This standard specifies: – methods of measurement and characterization of the output of ultrasonic physiotherapy equipment based on reference testing methods; – characteristics to be specified by manufacturers of ultrasonic physiotherapy equipment based on reference testing methods; – guidelines for safety of the ultrasonic field generated by ultrasonic physiotherapy equipment; – methods of measurement and characterization of the output of ultrasonic physiotherapy equipment based on routine testing methods; – and acceptance criteria for aspects of the output of ultrasonic physiotherapy equipment based on routine testing methods. Therapeutic value and methods of use of ultrasonic physiotherapy equipment are not covered by the scope of this standard. This third edition cancels and replaces the second edition published in 2007. It constitutes a technical revision which includes the following significant technical changes with respect to the previous edition: – restriction introduced of 0,2 W/cm 2 effective intensity during hydrophone measurements for treatment heads with ka?20, to limit the likelihood of cavitation; – change in the factor F ac, to determine the effective radiating area, from 1,354 to 1,333; – and change to SI units for terms and definitions. This publication is to be read in conjunction with /2.
PDF Catalog
| PDF Pages | PDF Title |
|---|---|
| 6 | English CONTENTS |
| 8 | INTRODUCTION |
| 9 | 1 Scope 2 Normative references |
| 10 | 3 Terms and definitions |
| 18 | 4 List of symbols |
| 20 | 5 Ultrasonic field specifications |
| 21 | 6 Conditions of measurement and test equipment used 6.1 General 6.2 Test vessel |
| 22 | 6.3 Hydrophone 6.4 rms or peak signal measurement 7 Type testing reference procedures and measurements 7.1 General |
| 23 | 7.2 Rated output power 7.3 Hydrophone measurements |
| 24 | 7.4 Effective radiating area |
| 25 | 7.5 Reference type testing parameters |
| 26 | 7.6 Acceptance criteria for reference type testing 8 Routine measurement procedure 8.1 General 8.2 Rated output power |
| 27 | 8.3 Effective radiating area 8.4 Beam non-uniformity ratio 8.5 Effective intensity 8.6 Acceptance criteria for routine testing |
| 28 | 9 Sampling and uncertainty determination 9.1 Reference type testing measurements 9.2 Routine measurements 9.3 Uncertainty determination |
| 29 | Annex A (informative) Guidance for performance and safety |
| 32 | Figures Figure A.1 ā Normalized, time-averaged values of acoustic intensity (unbroken line) and of one of its plane-wave approximations (broken line), existing on the axis of a circular piston source of ka = 30, versus the normalized distance sn, where sn = Ī»z/a2 FigureĀ A.2 ā Histogram of RBN values for 37 treatment heads of various diameter and frequency |
| 33 | Annex B (normative) Raster scan measurement and analysis procedures |
| 35 | Annex C (normative) Diametrical or line scan measurement and analysis procedures |
| 36 | Tables TableĀ C.1 ā Constitution of the transformed array [B] used for the analysis of half-line scans |
| 38 | Annex D (informative) Rationale concerning the beam cross-sectional area definition |
| 40 | FigureĀ D.1 ā Iso-pressure lines of a typical physiotherapy treatment head of small geometrical area (ka = 17) FigureĀ D.2 ā Plot of beam cross-sectional area against different limit values for a small range of values in distance along the beam alignment axis, z |
| 41 | FigureĀ D.3Ā āĀ Normalized values of beam cross-sectional area for IEC and FDA limit values for five transducers of different ka values |
| 42 | FigureĀ D.4Ā āĀ Range of values of the beam cross-sectional area (ABCS) with distance from the face of the treatment head FigureĀ D.5Ā āĀ Range of values of the normalized beam cross-sectional area (ABCS) with transducer ka |
| 43 | Annex E (informative) Factor used to convert the beam cross-sectional area (ABCS)at the face of the treatment head to the effective radiating area (AER) |
| 44 | FigureĀ E.1Ā āĀ Conversion factor Fac as a function of the ka product for ka product between 40 and 160 |
| 45 | Annex F (informative) Determining acoustic power through radiation force measurements |
| 46 | TableĀ F.1Ā āĀ Necessary target size, expressed as the minimum target radiusĀ b, as a function of the ultrasonic frequency, f, the effective radius of the treatment head, a1, and the target distance, z, calculated according toĀ A.5.3.1of IECĀ 61161: 2013 (seeĀ [6]) |
| 47 | Annex G (informative) Validity of low-power measurementsof the beam cross-sectional area (ABCS) TableĀ G.1Ā āĀ Variation of the beam cross-sectional area (ABCS(z)) with the indicated output power from two transducers |
| 48 | Annex H (informative) Influence of hydrophone effective diameter |
| 49 | TableĀ H.1Ā āĀ Comparison of measurements of the beam cross-sectional area (ABCS(z)) made using hydrophones of geometrical active element radii 0,3Ā mm, 0,5Ā mm and 2,0Ā mm |
| 50 | Annex I (informative) Effective radiating area measurement using a radiation force balance and absorbing apertures |
| 51 | FigureĀ I.1Ā āĀ Schematic representation of aperture measurement set-up |
| 54 | TableĀ I.1Ā āĀ Aperture measurement check sheet |
| 55 | FigureĀ I.2Ā āĀ Measured power as a function of aperture diameter for commercially-available 1Ā MHz physiotherapy treatment heads |
| 56 | TableĀ I.2Ā ā Annular power contributions TableĀ I.3Ā āĀ Annular intensity contributions |
| 57 | TableĀ I.4Ā āĀ Annular intensity contributions, sorted in descending order TableĀ I.5Ā āĀ Annular power contributions, sorted in descending order of intensity contribution |
| 58 | FigureĀ I.3Ā āĀ Cumulative sum of annular power contributions, previously sorted in descending order of intensity contribution, plotted against the cumulative sum of their respective annular areas TableĀ I.6Ā āĀ Cumulative sum of annular power contributions, previously sortedin descending order of intensity contribution, and the cumulative sum of their respective annular areas |
| 60 | Annex J (informative) Guidance on uncertainty determination |
| 62 | Bibliography |
