NPL contributes to landmark global ultrasound safety guidance
First international consensus on Thermal Index exposure limits developed.
3 minute read
New international guidelines on the safe use of diagnostic ultrasound have been published in Ultrasound in Medicine and Biology, bringing together, for the first time, a harmonised global position on recommended maximum exposure times associated with displayed Thermal Index values.
The Thermal Index is a safety indicator displayed on ultrasound scanners worldwide. It provides an estimate of the potential for ultrasound-induced tissue heating and is used by clinicians to help ensure examinations are performed safely while obtaining the required diagnostic information.
Developed through the World Federation for Ultrasound in Medicine and Biology, the guidance represents a rare international consensus between the world's leading ultrasound organisations and experts in ultrasound safety, including representatives from professional societies, academia and regulatory bodies such as the Food and Drug Administration (FDA).
Piero Miloro, Senior Delivery Manager at NPL, was invited to contribute as a member of the BMUS and ISUOG safety committees. He worked alongside internationally recognised leaders in ultrasound safety and bioeffects, including Professor J. Brian Fowlkes from the University of Michigan, Professor Gail ter Haar from the Institute of Cancer Research in London, and Dr Gerald Harris and Dr Keith Wear, both formerly of the FDA.
Diagnostic ultrasound is one of the most widely used medical imaging technologies in the world, supporting around one billion examinations every year. Maintaining its outstanding safety record is essential as new technologies and clinical applications continue to emerge.
The new guidance provides a single internationally agreed reference for manufacturers, clinicians, sonographers and researchers, helping to ensure the safe and effective use of ultrasound worldwide for years to come.
This achievement highlights NPL's continued contribution to international standards, measurement science and patient safety, and its role in supporting the safe use of medical ultrasound worldwide.
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21 Sep 2026