EN 61689:2007 – Ultrasonics – Physiotherapy systems – Field specifications and methods of measurement in the frequency range 0,5 MHz to 5 MHz

The numbers given in brackets are the tolerances defining the range of acceptable values for the results of either the type testing reference measurements specified in Clause 7 or the routine measurements specified in Clause 8.
If the published tolerance requirement cannot be met, then the 95 % confidence level that is achievable should be reported.
It shall then be demonstrated that the reported value, when incorporated with the tolerance so as to produce the ‘worst case’ value, remains with the range of acceptable values, as specified in IEC 60601 -2-5, and on which guidance is provided in Annex A.
The temperature range shall be specified for the parameters specified above.
The range of line voltages shall also be specified. For ultrasonic physiotherapy equipment using a treatment head capable of operating at more than one nominal value of acoustic working frequency , the parameters listed above shall be specified for each nominal value of acoustic working frequency .
In addition, for ultrasonic physiotherapy equipment which can use an attachment head , the parameters listed above shall be specified for each combination of attachment head and treatment head .
NOTE This document does not contain requirements relating to safety: these are covered in IEC 60601 -2-5. Guidance on performance and safety can be found in Annex A of this document. 6 Conditions of measurement and test equipment used
6.1 General All measurements shall be undertaken under approximately free-field conditions at a temperature of 22 ° C ± 3 ° C. If measurements are carried out at any other temperature, a test shall be undertaken to show that the results, determined in accordance with 7.6 and 8.3, are not dependent on the temperature at which the tests were undertaken.
Degassed water shall be used for the measurement of ultrasonic power, see 7.2. Degassed water is not essential for the hydrophone measurements, see 7.3. NOTE Degassed water is essential to avoid cavitation when the physiotherapy units are operated at or near full output power.
Information on preparation of water suitable for physiotherapy measurements may be found in IEC 61 1 61 , and in bibliographic reference [1 0].
All measurements shall be made after the warm-up period specified by the manufacturer. If no such period is specified, a period of 30 min shall be used.
EN 61689:2007 – Ultrasonics – Physiotherapy systems – Field specifications and methods of measurement in the frequency range 0,5 MHz to 5 MHz