Annual report 2023

The French Institute for radiation protection and nuclear safety (IRSN) is the public expert on nuclear and radiological risks.

As a Public Industrial and Commercial Establishment (“EPIC” – Établissement public à caractère industriel et commercial) overseen jointly by the French ministers in charge of the ecological transition, the Armed Forces, energy, research, and health, IRSN is fully in line with the State’s modernisation policies, as testified by its risk management approach and by its implementation of a global corporate social responsibility policy.

IRSN’s missions serving public authorities and the population are to assess, research, protect, anticipate, and share. The institute’s singularity lies in its ability to combine researchers and experts to anticipate future questions on the development and management of nuclear and radiation risks. IRSN teams are keen to publish their work and share their knowledge with society, thereby helping to improve access to information and dialog with stakeholders.

Independence, anticipation, excellence, and sharing are IRSN’s essential ambitions in order to contribute to public nuclear safety and security, health, environment, and crisis management policies.



Marie-France Bellin,

Marie-France Bellin,

Chairwoman of the Board

Jean-Christophe Niel,

Jean-Christophe Niel,

Director General of IRSN

Louis-Michel Guillaume,

Louis-Michel Guillaume,

Deputy Director General in charge of the Defense-related missions

Anticipating and meeting the challenges of the new nuclear landscape.

For IRSN, the revival of the French nuclear sector is already a reality

Throughout 2023, the Institute’s experts examined many files relating to the extension of the operation of the fleet of nuclear power stations in service beyond 40 years, in particular the study of the behavior of the containment buildings of 1,300 MWe reactors, the consideration of climate change, and beyond 60 years, with the investigation of aging and obsolescence over lengths of time that have not been studied to date. IRSN completed the safety review of the Flamanville EPR and continued monitoring the reactor start-up tests. With a view to the construction of the 6 + 8 EPR2 reactors announced by the French President, IRSN has also published fifteen technical notices on the EPR2, incorporating the lessons learned from the reviews of the reactors in operation and those from the review of the EPR.

In parallel with this work, 2023 saw the intensification of exchanges with project owners of small modular reactors, be it Nuward, whose design is inspired by that of pressurized water reactors operating in France or abroad, or other reactors, based on technological breakthroughs requiring significant appraisal work on the part of the Institute.

This very substantial work program requires prioritization of the files put before IRSN with regard to the issues involved.

In support of its current and future expert appraisal work, the Institute is continuing with research projects such as PASTIS, relating to passive safety systems; CABRI, dedicated to the study of the resistance of fuels in the event of a reactivity accident; and MACUMBA, dedicated to the study of the containment provided by concrete walls.

Advances based on a long-term strategic vision

Since its creation, IRSN has always been of the conviction that progress made in both nuclear safety and radiation protection relies on a long-term strategic vision. This conviction has guided the development, since the end of the 1990s, of the ASTEC code for the simulation of severe accidents, which can be used for all nuclear installations: reactors of all types, power plants, etc. This code, which has become the European reference code, brings together both the most advanced modeling and all experimental knowledge related to severe accidents. It is this conviction that inspired the Institute’s multi-year strategy in terms of research and appraisal in radiation protection, for which IRSN plays a key role at both European and international level, within bodies such as ICRP or UNSCEAR, to serve as a benchmark institution with which, for example, the WHO and the IAEA collaborate. This is evidenced by the new agreements signed with the latter two bodies, covering topics such as the medical and health management of a radiological or nuclear accident, or the quality of radiotherapy care and the welfare of cancer patients. Concerning research, this multi-annual strategic approach was notably implemented in the establishment of PIANOFORTE, a European partnership coordinated by the Institute. This brings together a consortium of 58 partners from 22 countries in the European Union as well as the United Kingdom and Norway, and which organizes all radiation protection research in Europe. And it is this self-same conviction that has led IRSN to develop a mode of organization and the means for managing radiological and nuclear emergencies – in particular the LATAC laboratory, inaugurated in 2023 – the widely acknowledged quality of which has led to the Institute being requested by the Government to provide its technical support in the context of global events such as the Rugby World Cup and the Paris Olympic and Paralympic Games.

Continuing with and building on the transformation projects underway

Throughout 2023, IRSN has been involved in the reform of nuclear safety and radiation protection inspection and research as desired by the Government, with a priority being to maintain the level of quality of research and expert appraisal expected by our fellow citizens. This quality is based in particular on the close coupling of research and appraisal activities, the strict separation of appraisal and decision-making, the coherence of safety and radiation protection approaches at both European and international level, and maintaining the appeal of the professions exercised within the Institute.

In order to help boost the performance of the appraisal and inspection expertise of tomorrow, IRSN has in 2023 continued with and built upon various transformation projects that have been underway for several years, be it skills development with IRSN Academy and the internal university, forward planning for jobs and skills, developing digital solutions and artificial intelligence to take advantage of new technologies with a view to enhancing assessment and research, or the consideration of societal requirements in terms of scientific integrity, CSR, and ethics.

At the time of writing, the ongoing reform of inspection and research in nuclear safety and security and radiation protection may make this 2023 annual report the last one to be published by IRSN.
The men and women who have worked tirelessly since 2001 to make the Institute what it is today will carry on striving in the future to ensure that the high profile of French research and expertise in nuclear safety and radiation protection continues to be maintained. We would like to commend their commitment to the common good, their investment in their duties, their professionalism, and their openness.

Serving nuclear safety and security

2023 will have been marked by the uncertainty arising from the ongoing process of reform to the nuclear safety and radiation protection inspection system. In this context, the teams of the IRSN Nuclear Defense Appraisal Department (DEND) have succeeded in carrying out the multiple missions entrusted to them in fields as diverse as the safety of nuclear installations and materials, transportation, studies of cybersecurity and of the modeling of the effects of explosions, safety appraisals of defense-related systems and facilities, and nuclear and chemical non-proliferation. In all these areas, they have continued to provide their support to the public authorities on issues as essential as the future nuclear aircraft carrier, the 3rd-generation nuclear ballistic missile submarine, and the Barracuda program, for which 2023 saw the commissioning of the 2nd Suffren-class nuclear attack submarine.

Under the Law on the organization of the governance of nuclear safety and radiation protection to meet the challenge of the revival of the nuclear sector, these multiple appraisal and inspection activities will be conducted, from January 1, 2025, within the Ministry of Defense, in support of the public authorities in the fields of nuclear defense safety, nuclear safety of civilian facilities, and non-proliferation, where the public authorities are on the front line.

The teams in charge of these missions today look forward to continuing with these missions on behalf of their usual beneficiaries: DNSD, Senior Defense and Security Officers, Euratom Technical Committee, and many more.


Protecting the health
of people and
the environment



At the start of a decade of major
challenges for safety appraisals

Mobilizing teams and
expanding capacities
for action