Dr. Gillian Hirth was appointed as Chief Executive Officer of the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) in March 2022, after serving for almost six years as Head, Radiation Health Services (RHS) Branch of ARPANSA and Deputy Chief Executive Officer of ARPANSA.
Dr. Hirth completed a PhD in environmental radiochemistry in 1999 and from 2000 to 2003 she was a Post-Doctoral Research Fellow at the Australian Nuclear Science and Technology Organisation. Her research focussed on the transport of uranium decay series in the environment and their transfer to the biota.
Dr. Hirth worked for the Australian Defence Organisation from 2003 to 2010 in the field of hazardous materials and environmental management, this work included the management of radiation sources and facilities, nuclear materials, occupational exposures and waste across the organisation. She has been with ARPANSA since 2010 initially working in codes and standards development she then led a project examining radionuclide activity concentration ratios in wildlife inhabiting uranium mining environments and was Director of the Monitoring and Emergency Response Section in RHS Branch from 2014 to August 2016.
Dr. Hirth is the current Australian representative on the International Atomic Energy Agency (IAEA) Commission on Safety Standards of the for the 8th term, 2024-2027, and was the representative also during the 7th term, 2020-2023, and was the Australian representative on the IAEA's Emergency Preparedness and Response Safety Standards Committee for the term 2015-2017. Dr. Hirth was a member of the International Commission on Radiological Protection (ICRP) Committee 4 for the term 2017-2021, and a member of the ICRP Main Commission for the term 2021-2025.
Dr. Hirth was appointed an Officer of the Order of Australia in June 2024 for ‘distinguished service to environmental science, particularly radiation and nuclear safety, and to the development of national and international regulatory standards’ as part of the King’s Birthday 2024 Honours List.
Dr. Hirth joined the Australian delegation in 2013, was alternate representative from 2014 to 2016 and is the Australian Representative since the sixty-fourth session in 2017.
Dr Ivan Williams was appointed as Chief Medical Radiation Scientist and Head of Australian Radiation Protection and Nuclear Safety Agency’s (ARPANSA) Medical Radiation Branch in 2015 after seven years as the inaugural Director of the first national radiotherapy dosimetry auditing service in Australia, the Australian Clinical Dosimetry Service, (ACDS).
Dr Williams trained in Medical Physics at the Peter MacCallum Cancer Centre in Melbourne Australia, successfully completing his Medical Physics Specialist exams in Radiation Oncology before embarking on a PhD in 2004. During his time at the PeterMac, Ivan also competed a MSc in physics describing his work in designing and building a parallel plate ionising chamber from novel materials. Ivan completed his PhD investigating the application of phase contrast imaging with conventional sources within mammography in 2008.
After completing his PhD, Dr Williams worked at St Luke’s Hospital Ireland, initial as Principal Physicist, and then as Acting Head of Department before returning to Australia in 2010 to take up the role as the inaugural Director of the ACDS within ARPANSA. While working for ARPANSA, Dr Williams has been appointed to numerous government advisory committees, providing expert advice on clinical practice, future technology trends and industry risk.
Dr Williams is a member of the International Committee of Radiological Protection, (ICRP), Committee 3 for the term 2021 – 2024, and has been reappointed until 2029. Dr Williams first attended UNSCEAR in 2024 as alternate representative.
