BSI BS EN IEC 61847:2025

IEC 61847:2025 specifies:
– the essential non-thermal output characteristics of ultrasonic surgical units;
– methods of measurement of these output characteristics;
– those characteristics to be declared by the manufacturers of such equipment.

This document is applicable to equipment which meets the criteria of a), b) and c) below:

• a) ultrasonic surgical systems operating in the frequency range 20 kHz to 120 kHz; and
• b) ultrasonic surgical systems whose use is the fragmentation, emulsification, debridement, or cutting of human tissue, whether or not those effects are delivered in conjunction with tissue removal or coagulation; and
• c) ultrasonic surgical systems in which an acoustic wave is conducted by means of a specifically designed wave guide to deliver energy to the surgical site.

This document is not applicable to:

• lithotripsy equipment which uses extracorporeally induced pressure pulses, focused through liquid conducting media and the soft tissues of the body;
• surgical systems used as part of the therapeutic process (hyperthermia systems);
• surgical systems whose mechanism of action is through frictional heat generated by tissue in contact with the wave guide, e.g. clamp coagulators or clamping vibrational cutters;
• surgical systems whose mechanism of action is through focused ultrasound for either thermal degradation (high intensity focused ultrasound – HIFU or HITU) or cavitation erosion (Histotripsy) of tissue remote from the ultrasound transducer;
• surgical systems whose mechanism of action is through erosion of hard tissues in contact with the applicator tip, e.g. bone cutting or drilling.

This document does not deal with the effectiveness or safety of ultrasonic surgical systems.

This document does not deal with airborne noise from the systems, which can affect operators and patients.

IEC 61847:2025 cancels and replaces the first edition published in 1998. This edition constitutes a technical revision.

This edition includes the following significant technical changes with respect to the previous edition:

• a) The upper frequency covered by this document has been raised from 60 kHz to 120 kHz.
• b) The hydrophone method of measuring ultrasound power is now normative. Because of difficulties in using the calorimetry method of measuring ultrasound power, it is no longer the primary approach.
• c) It is recognised that some systems can have more than one mode of vibration under user control, and the measurement techniques and declarations have been updated to address this.
• d) The high-frequency component, which relates to cavitation developed at the applicator tip and the vibration amplitude at which cavitation occurs is addressed.
• e) Specific requirements for measurement at excursion levels where no cavitation is present, and extrapolation to maximum excursion level(s) are described.
• f) Guidance is provided to adapt the methodology described to more complex designs and vibration patterns, excursion directions, and their output characteristics.
• g) Guidance is provided with respect to measurement tank arrangements for different types of systems.
• h) The list of ultrasound methods and systems not covered by this document was extended to incorporate recent developments.
• i) Definitions for cavitation related terms were added.
• j) Requirements for the measurement of directivity characteristics of the applicator tip were changed.
• k) Annex A was modified and Figure A.1 wa