«Thanks to modern radiation protection and technical progress, individual and collective doses in nuclear facilities have continuously decreased»


ENSI took part in the third IAEA International Conference on Occupational Radiation Protection from 5 to 9 September 2022. Conferences like this help to improve the safety of workers exposed to radiation even more and to further develop the work and safety culture of licensees and regulators, said ENSI Director General Marc Kenzelmann at the opening of the conference in Geneva.

The third International Conference on Occupational Radiation Protection was held in Geneva from 5 to 9 September 2022. The International Atomic Energy Agency (IAEA) is behind the conference, which was hosted by Switzerland, namely the Federal Office of Public Health (FOPH). The meeting was co-sponsored by the International Labour Organisation and in cooperation with other international organisations. The first conference on this topic was held in August 2002, also in Geneva.

The conference focused on “Strengthening Radiation Protection of Workers – Twenty Years of Progress and the Way Forward”.

ENSI Director General Marc Kenzelmann made a statement at the opening of the conference on 5 September on the supervision of personnel exposed to radiation in nuclear facilities in Switzerland:

Ladies and gentlemen, we are all united here in Geneva to strengthen radiation protection for workers. ENSI is also part of this community and pursues the same goal.

ENSI has been the independent supervisory authority for nuclear facilities in Switzerland since 2009 and is responsible for nuclear and radiation safety, and nuclear security. We employ over 160 people and we supervise 5 nuclear power plants, one of which is currently being dismantled. We also supervise a central interim storage facility, other interim storage facilities at the NPP sites and various nuclear research facilities and labs. And for the hopefully not so distant future, we are also supervising the licensing of a deep geological repository as final radioactive waste disposal solution for Switzerland.

In Switzerland, some of the oldest nuclear reactors in the world are operated, but the principle of continuous improvement enshrined in the nuclear energy act since the beginning has been used not only for an early comprehensive ageing surveillance programme, but also for extensive backfitting for the nuclear power plants. For example, the Swiss operators backfitted additional bunkered so-called special emergency systems and filtered containment venting systems in all the plants more than 30 years ago. Furthermore, the protection against flooding and the seismic robustness of the plants were re-qualified and strengthened.

In ENSI’s supervisory area, around 6000 people are monitored dosimetrically, accumulating a collective dose of around 3 to 5 man-sievert per year. For the protection of workers and risk minimization, ENSI consistently implements the international recommendations on radiation protection in its regulatory framework. Such regulatory provisions are important in nuclear industry, and they are only as good as long as they consider the lessons learned from past radiation incidents and accidents and the latest scientific findings. And let’s not forget safety culture applied in radiation protection. The latter is important so that those exposed to radiation in their workplace are willing to comply with the rules. Here risk communication, appropriate to the target audience, is essential.

What constitutes a good safety culture? In my opinion, confidence is at the heart of it. Confidence that one has done everything possible to avoid incidents and accidents, and confidence that one can report any deviation or abnormality transparently and without fear. This is the basis for improving radiation protection and occupational safety as a whole.

At the conference this week, people from different cultural backgrounds meet and we look back to the developments in radiation protection over the last 20 years and discuss about the way ahead. I am pleased that ENSI is part of it.

It is a fact that in Swiss nuclear facilities individual and collective doses have continuously decreased over the years thanks to modern radiation protection and technical progress. May we expect those doses to decrease any further? By applying the methods of justification and optimization, we talk about the well-known ALARA principle, meaning “As Low As Reasonably Achievable”, but also taking into account economic and societal factors.

Now, what does “Reasonable” mean in ALARA? This is an interesting question without a final answer. We, as radiation protection community, need to keep asking ourselves this question again and again as science progresses, practical experience is accumulated and cultural backgrounds vary. The assessment of radiation protection measures involves the expertise of many people. And in this assessmen, there is a risk evaluation. The question is: How harmful is radiation exposure? How likely is a disease? What level of exposure is acceptable? And how much should protective measures cost?

This week, numerous experts from all over the world are gathering here in Geneva. We have the chance to ask ourselves these questions, to exchange ideas and to learn from each other. With this exchange, I hope to gain new insights to improve the safety of workers exposed to radiation even more and to further develop the work and safety culture of licensees and regulators.

After the long years of the Covid pandemic, this conference also provides an opportunity to refresh and maintain our personal relationships and our networks. I would like to take this opportunity to express my sincere thanks to the IAEA, the ILO, the supporting institutions and the organizing committee for this event, and I wish for you, esteemed participants, interesting presentations, new insights and fruitful discussions.