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Professor William Evans MBE MA(Oxon) PhD(Wales) FInstP FIPEM FSRP HonMRCR CPhys CSci CRadP

Professor William Evans

MBE MA(Oxon) PhD(Wales) FInstP FIPEM FSRP HonMRCR CPhys CSci CRadP

Honorary Professor

+44 (0)77 0217 4012
Medical Physics - Room GTB2/09, Main Hospital Building, University Hospital of Wales, Heath Park, Cardiff, CF14 4XN
Welsh speaking
Available for postgraduate supervision


I am a medical physicist and registered clinical scientist; I worked in the National Health Service for over 40 years. In 2017, I retired as Head of Medical Physics and Clinical Engineering in the Cardiff and Vale University Health Board, based at the University Hospital of Wales. The responsibilities of the post included the provision of a wide range of clinical, scientific and technical services but my own areas of expertise were nuclear medicine, bone densitometry, body composition measurement and radiation safety. In 2021, I returned to work for the Health Board as a Consultant Clinical Scientist ito support the bone densitometry and osteoporosis services.

Throughout my career, I have had a strong interest in teaching, training and research. I am an Honorary Professor in the School of Engineering and I have co-supervised several PhD students whose projects have involved various aspects of medical radiation physics and engineering.  In addition, I have acted as reviewer and internal examiner for Cardiff University research degrees.



1981-1983           University College Cardiff: Postgraduate Diploma (Computer Studies)

1972-1976           University of Wales (University College Cardiff): PhD (Atomic Physics)

1969-1972           University of Oxford (Jesus College): BA (Physics), MA (1976)

1962-1969           Whitland Grammar School, Carmarthenshire: O level and A/S level Certificates

1956-1962           Pantycaws County Primary School, Carmarthenshire: Eleven Plus Certificate

NHS Appointments

2021-Present      Consultant Clinical Scientist, Cardiff and Vale University Health Board

2017-2021          Honorary Consultant Clinical Scientist, Cardiff and Vale University Health Board

2010-2017          Head of Medical Physics and Clinical Engineering, Cardiff and Vale University Health Board

2003-2010          Consultant Clinical Scientist and Head of Medical Physics, Cardiff and Vale University Health Board

1995-2003           Consultant Medical Physicist, Cardiff and Vale NHS Trust

1984-1995           Principal Medical Physicist, University Hospital of Wales Healthcare NHS Trust

1979-1984           Senior Medical Physicist, South Glamorgan Health Authority

1976-1979           Basic Grade Medical Physicist, South Glamorgan Health Authority

Honours and awards

2014                     Member of the Order of the British Empire (MBE) for services to the NHS in Wales and overseas

2009                     Honorary Member, Royal College of Radiologists (HonMRCR)

2005                     Honorary Certificate of Competence, Bone Densitometry Practitioner, National Osteoporosis Society

1983                     Medical Fellowship, Council of Europe

1972                     Marion Bradley Physics Prize, Jesus College, Oxford

1967                     Carmarthenshire Schools Representative, London Youth Science Fortnight

Professional memberships

2022                     Associate of the National School of Healthcare Science (ANSHCS)

2013                     Fellow, Society for Radiological Protection (FSRP)

2008                     Chartered Radiation Protection Professional, Radiation Protection Council (CRadP)

2004                     Chartered Scientist, Science Council (CSci)

2002                     Registered Clinical Scientist, Health and Care Professions Council

1994                     Fellow, Institute of Physics (FInstP)

1991                     Cert. of Competence, Radiation Protection Adviser, Institution of Physics & Engineering in Med. & Biol.

1990                     Fellow, Institute of Physics and Engineering in Medicine (FIPEM)

1985                     Chartered Physicist, Institute of Physics (CPhys)

Academic positions

 2014                     External Examiner (PhD), University of Nottingham

2011-Present      Honorary Professor, School of Engineering, Cardiff University

2010                     External Examiner (MD), University of Colombo, Sri Lanka

2009-2013          Visiting Lecturer (BSc), University of Swansea

2008-Present     International Adviser, SRM University, Chennai (Madras), India

2008-2009          Ext. Examiner (MRad/MMed), Univ. of Malaya, National Univ. of Malaysia and Science Univ. of Malaysia

2001-Present      Internal Examiner (PhD), Schools of Engineering and Medicine, Cardiff University

1996                     External Examiner (PhD), University of Swansea

1996                     External Examiner (MPhil), University of Glamorgan

1990-2016          Honorary Lecturer and Internal Examiner (BSc), School of Physics and Astronomy, Cardiff University

1989                     External Examiner (PhD), University of Leeds

Speaking engagements


2008    Overview of methods for bone densitometry: SRM University National Workshop on Bone Densitometry, Kattankulathur, India and Jerusalem College of Engineering, Chennai (Madras), India

2008    Interpretation and role of bone densitometry and Principles of dual energy x-ray absorptiometry (DXA): SRM University National Workshop on Bone Densitometry, Kattankulathur, India, 2008

2008    Nuclear medicine in sentinel node localisation and The measurement of bone mineral density: Updates in Ionizing Radiation, University of Malaya, Kuala Lumpur, Malaysia

2006    Principles of operation of DXA systems and Scientific and technical principles of DXA: DXA Radiation Protection Seminar, European Commission SENTINEL (Safety and Efficacy for New Techniques and Imaging using New Equipment to support European Legislation) Project, Dublin, Ireland, 2006

2005    Sentinel node biopsy and the role of nuclear medicine: Annual Conference of the Association of Medical Physicists of India, Chennai (Madras), India and Pondicherry Institute of Medical Sciences, Pondicherry, India

2004    Advances in magnetic resonance imaging and Science and Technology of positron emission tomography: Joint scientific meeting of the Lebanese Society of Radiology and the Pan Arab Neuroradiology Society – Technical Satellite Symposium, Beirut, Lebanon

1994    Bone density measurement  K J Hospital, Madras, India

1994    Methods of measuring bone density  Tenth Annual Conference of the Indian Rheumatism Association, Madras, India

1983    Photon absorptiometry for elemental analysis in vivo  University of Gothenburg Radiation Physics Department, Sahlgren Hospital, Gothenburg, Sweden


2017    Reflections on a life in medical physics  All Wales Medical Physics and Clinical Engineering Summer meeting, Swansea

2007    Advances in medical physics  Physics Update – A course for practising science teachers.  Institute of Physics, Cardiff

2006    The role of nuclear medicine in sentinel node biopsy for breast cancer  Image Matters – Raising the Image 2006.  Royal College of Nursing Imaging Nurses Forum Conference, Cardiff

2006    The role of imaging in the diagnosis of osteoporosis  Royal Society of Medicine Conference: Key Advances in the Clinical Management of Osteoporosis, Cardiff

2005    Pre-operative nuclear medicine in sentinel lymph node biopsy  Annual Meeting of the Association of Surgeons of Great Britain and Ireland, NEW START Sentinel Lymph Node Biopsy Training Day, Glasgow

2000    Radiation physics and protection for the surgeon  First ALMANAC (Axillary Lymphatic Mapping Against Nodal Axillary Clearance) Symposium, Cardiff

2002    Datblygiadau mewn delweddu meddygol (Developments in medical imaging, in Welsh)  Cymdeithas Wyddonol Cylch Caerdydd (Cardiff and District Scientific Society)

1999    Dilemmas in paediatric bone densitometry  Wales, South West and Wessex Osteoporosis Group, 15th Biannual Meeting, Chepstow

1997    Routine radiometry and equipment servicing - what you should be doing  Psoralen and Ultra Violet A (PUVA)/Phototherapy Study Day for Dermatologists, Cardiff

1997    How do we measure your bone density?  Women’s Health Day - Osteoporosis, the Menopause and HRT.  Standing Conference of Women’s Organisations, Cardiff

1996    Osteoporosis and bone mineral measurement Breast Test Wales, Cardiff and Breast Test Wales, Swansea

1992    Methods of measuring bone density  The Menopause: Management and Recent Developments - A study day for health professionals, University College of Swansea

1990    Quantitative CT and other methods of bone mineral measurement Innovative Imaging.  Association of Medical Technologists Annual Exhibition and Conference, Cardiff

1990    Ymbelydredd – ffrind neu elyn? (Radiation - friend or foe? in Welsh)  Eisteddfod Genedlaethol Cymru – Adran Wyddonol (National Eisteddfod of Wales - Scientific Section), Rhymney Valley

1980s  A little radioactivity does you good!  The application of radionuclides in medicine  (1) Cardiff Scientific Society, 1990  (2) Techniquest, Cardiff, 1989  (3) Annual Meeting of the Association for Science Education, Cardiff, 1987  (4) Physical Society, University College of Wales, Aberystwyth, 1988  (5) South Wales Region, Association for Science Education, Cardiff, 1983  (6) Department of Physics, University College, Cardiff, 1981

1986    Measurement of bone mineral content by single photon absorptiometry  Meeting of South Wales Bone Research Group, Cardiff

1985    Tonnau ar waith mewn meddygaeth (Waves at work in medicine, in Welsh with GM Owen)  Arddangosfa Gwyddoniaeth a Thechnoleg, Eisteddford Genedlaethol Urdd Gobaith Cymru (Science and Technology Exhibition, National Youth Eisteddfod of Wales), Cardiff

1982    Computers in the x-ray department  Meeting of the All-Wales Superintendent and Tutor Radiographers Committee, Aberystwyth

Committees and reviewing


Grant application reviewer for 5 scientific organisations:

  • National Osteoporosis Society
  • Nuffield Foundation
  • Royal Academy of Engineering (Research Fellowship Programme)
  • UK Department of Health (Policy Research Programme)
  • Wellcome Trust

Manuscript reviewer for 14 scientific journals:

  • Biomedical Engineering and Physics Express
  • British Journal of Radiology
  • Clinical Physics and Physiological Measurement
  • Cost Effectiveness and Resource Allocation
  • IET Science Measurement and Technology
  • Journal of Endocrinological Investigation
  • Journal of Medical Engineering and Technology
  • Journal of Physics D: Applied Physics,
  • Journal of Radiological Protection
  • Measurement Science and Technology
  • Medical Engineering and Physics
  • Physics in Medicine and Biology
  • Reports on Progress in Physics,
  • Ultrasound in Medicine and Biology


2017-Present  Member: Honours Nominations Advisory Committee, Institute of Physics and Engineering in Medicine (IPEM)

2016-Present  Lay Member: University Research Integrity and Ethics Committee, Cardiff University

2013-Present  Member: Board of Studies, MSc in Clinical Science (Medical Physics) and MSc in Medical Radiation Physics, Swansea University

2011-2012       Subject Expert and Lead Assessor for Radiation Protection Research Commissioning: Policy Research Programme, Department of Health (London)

2010-2015       Member and Chair, Authorisations Working Group: Committee on Medical Aspects of Radiation in the Environment (COMARE), Department of Health (London); member of Medical Practices sub-committee from 2011

2009-2013       Chair: Bone Densitometry Training and Advisory Panel (member until 2015) and member: Clinical and Scientific Committee, National Osteoporosis Society

2009-2011       Member and medical physics representative: National Imaging Programme Board (NIPB), Welsh Government

2005-2008       Member: Stakeholder Boards, National Leadership and Innovation Agency for Healthcare and Workforce Development Unit, NHS Wales

2004-2008       Chair: Welsh Scientific Advisory Committee (WSAC) (member from 2001-2017 and vice-chairman 2002-2004) and member: Joint Professional Forum, Department of Health and Social Care, Welsh Government

2004-Present  Member: Fellowship Panel, Institute of Physics

2004-2009       Vice Chair: Imaging Modernisation Forum, Welsh Government

2004-2006       Member: Advisory Board for Healthcare Standards in Wales, Welsh Government

2003-2013       Member: Administration of Radioactive Substances Advisory Committee (ARSAC), Department of Health (London) and Chair, Therapy sub-group from 2010

2003-2004       Chair: Medical Physics and Clinical Engineering sub-committee, WSAC (member 1998-2017 and Vice-chairman 2001-2003)

2002-Present  Member: All Wales Osteoporosis Advisory Group Committee (Treasurer 2005-2017)

2001-2009       Chair: Cardiff and District Group, National Osteoporosis Society (Treasurer from 1994 and founder member from 1990)

1993-1996     Honorary President, Cymdeithas Wyddonol Cylch Caerdydd (Cardiff and District Scientific Society), Treasurer 1986-1991

1983-1986       Secretary/Treasurer: South Wales Branch Committee, Institute of Physics (member on three occasions from 1974-1987)

1983-1986       Secretary, Publications Committee and member, Scientific Committee, Institute of Physical Sciences in Medicine (IPSM) (Publications Committee member 1981-1983)

1981-1983       Secretary: South Western Group, Hospital Physicists Association

1978-1981       Regional Representative for Wales, Hospital Physicists Association

1973-1975       Chairman: Physics Department Staff-Student Committee and Secretary: Physics Society, University College Cardiff

1970-1972       Treasurer: Cymdeithas Dafydd ap Gwilym (Oxford University Welsh Society)




































Cardiff University

1998-2001         Lecturer (Radiation Physics and Radiation Protection): Intra-operative Lymphatic Mapping Course, Department of Surgery, School of Medicine

1996-2000         Supervisor (Medical Physics): special study module for MB BCh medical students, School of Medicine

1995-2012         Lecturer (Digital Imaging): Oral Radiography module for BDS dental students, School of Dentistry

1990-2014         Lecturer, module organiser (Radiation in Medical Diagnosis) and project supervisor: BSc in Physics with Medical Physics, School of Physics and Astronomy

1988-1991         Lecturer (Nuclear Medicine Instrumentation): MSc in Medical Electronics, University College, Cardiff

1982-1990         Lecturer and module organiser (Medical Physics): BSc in Physics, University College, Cardiff

1972-1975         Demonstrator: Physics laboratories and exercise classes, University College Cardiff

Professional Bodies

2004-2007            Lecturer (Radiation Probes, Radionuclide Imaging and Radiation Protection): NEW START sentinel lymph node biopsy training programme, Royal College of Surgeons

2002-2013            Lecturer (Physics and Radiation Protection) and portfolio assessor: National Training Scheme for Bone Densitometry, National Osteoporosis Society

1990-2013         Lecturer (Radiological Physics): South Wales Training Scheme in Clinical Radiology, Royal College of Radiologists

1979-1984         Lecturer (Physics): School of Radiography, University Hospital of Wales for Diploma of the College of Radiographers

Other Organisations

2009-2015         Lecturer (Radiological Physics): Clinical Radiology Training Scheme, Sheik Khalifa Medical City, Abu Dhabi and Tawam Hospital, Al Ain, Emirate of Abu Dhabi Health Authority, United Arab Emirates

2009-2013         Lecturer (Radiological Physics): BSc in Clinical Technology, School of Health Science, Swansea University

1997-2014         Lecturer (Radiological Physics): Clinical Radiology Training Scheme, American University of Beirut Medical Centre, Beirut, Lebanon

Training Roles

2018-Present  Member: Scientist Training Programme (STP) and Higher Specialist Scientific Training (HSST) Programme in Medical Physics, National School of Healthcare Science (NSHCS)

2016                Member: Development and Implementation Team, HSST in Medical Physics in Wales, Workforce, Education and Development Services (WEDS), NHS Wales

2013-2014       Member and curriculum content author: Working Group for the HSST in Medical Physics, Royal College of Radiologists (RCR) and Institute of Physics and Engineering in Medicine (IPEM)

2010-Present  Editor of Physics Module: Radiology Integrated Training Initiative (RITI) on-line learning programme for radiologists, RCR, Department of Health and the NHS

2004-2009       Member: Physics Working Group, RCR (Senior Physicist 2007-2008 and member of Fellowship Examining Board) – author of revised curriculum for FRCR Part 1 Physics examination approved by the Postgraduate Medical Education and Training Board (PMETB)

2002-2006       Chair: Training Centre Accreditation Panel, IPEM (member to 2008)

1999-2010       Nuclear Medicine examiner and member of the Board of Examiners: Part 1 training scheme for Medical Physicists and Clinical Engineers in Health Care, IPEM


Throughout my career, I have undertaken collaborative research and development with university academics and professional colleagues from a wide range of medical and surgical specialties.

This work has mainly involved the clinical application of physics and engineering in nuclear medicine, bone densitometry and body composition measurement.  However, it has also included radiation safety and the evaluation of equipment and techniques.  For an indication of the range of projects, please see the papers under the Publications tab, although a more comprehensive list appears in my ResearchGate profile.

My current research interests include optimisation in x-ray radiological imaging, standardisation of activity in radionuclide imaging, and identification and quantitation of radionuclidic impurities in radiopharmaceuticals and radioactive by-products in medical radioisotope production.


I am interested in co-supervising postgraduate research students in the following disciplines:

  • Medical radiation physics and engineering
  • Medical applications of radioactivity
  • Medical imaging physics and engineering
  • Nuclear medicine physics
  • Measurement of bone density and body composition

Current supervision

Andrew Fenwick

Research student

Past projects

I was a co-supervisor for the following Cardiff University PhD projects:

  • Identification and quantification of radioactive impurities in medical radionuclides - Ansam Al-Obaidi (awarded 2019)
  • A robust technique for the detection and quantification of abdominal aortic calcification using dual-energy x-ray absorptiometry - Karima Elmasri (awarded 2018)
  • Calibration of a scanning whole body counter for measurement of the activity of gamma emitting radionuclides in the human body – Thaer Al‑Musawi (awarded 2018)
  • Comparison of peripheral quantitative computed tomography and magnetic resonance imaging for tissue characterisation in the gastrocnemius muscle – Fahad Al-Gohani (awarded 2017)
  • Monte Carlo simulation applied to uncertainties in iodine-123 assay and thyroid uptake measurement - Matthew Talboys (awarded 2016)
  • The influence of accurate attenuation correction on quantitative gamma camera imaging - Helen Blundell (awarded 2013)
  • Effect of intra-abdominal fat on the accuracy of DXA lumbar spine bone mineral density measurement using DXA body composition measurements - Sarah Darlington (awarded 2013)
  • Measurement of caesium-137 in the human body using a whole body counter - Elkhadra Elessawi (awarded 2011)