“2023 was an iconic year for IRSN. First, there was the evaluation report by the High Council for the Evaluation of Research and Higher Education (Hcéres): published in March, it was positive in tone and recognized the quality of the Institute’s research, its leadership at the European level in several areas and its proactive commitment to open up to society. Among the strengths, Hcéres noted IRSN’s adaptive approach and clear, forward-looking vision to meet the requirements of the authorities, public authorities and society. Finally, it recognized the legitimacy of its goals for 2022–2026 of being a responsible and socially-aware scientific institution.
Even more than the resumption of the CABRI reactor tests, this position as a responsible and socially-aware scientific institution has already been shown in several achievements in 2023:
Finally, I would like to mention two major landmarks of radiation protection research in 2023: the change in scale in radioecology, which is now investigating the effects on ecosystems and the services they provide, and the publication of IRSN’s work on the linear no-threshold law, which brings reliability to the international radiation protection system.”
Patrice Bueso
Strategy Director
Like any research organization, IRSN attaches fundamental importance to training in and through research. Its doctoral program is an essential vehicle for transferring knowledge and skills to young people, as well an exceptional framework for investing in new areas and deploying its partnership policy.
The hundred PhD students at IRSN represent nearly one third of the human resources that the Institute devotes to scientific production. 30 new theses were launched in 2023, 26 by PhD students employed by IRSN. This work covers all areas of research. In addition, 33 theses were defended, in the following areas: 12 in safety (including one concerning defense facilities), 11 in health and 10 in the environment.
A high point in the life of PhD students, this event took place at the end of March. It brought together 220 participants, including 91 PhD students from the Institute, their supervisors, and representatives from IRSN’s main scientific partners. The second- and third-year PhD students reported on the progress of their work and welcomed the first-year students. The agenda included the challenges of artificial intelligence and climate change, with a conference on AI and a Climate Fresk workshop, respectively.
Chaired by the Director General of IRSN, the NEA/OECD’s Committee on the Safety of Nuclear Installations (CSNI) is tasked with identifying the research needs in the nuclear safety area so that the international community can therefore undertake cooperative projects.
In 2023, the CSNI began writing a roadmap for the next 15 years, in order to determine the programs to be launched, in the current context of the revival of nuclear power and the actors’ willingness to extend the operation of facilities.
One of the major contributions of the NEA and CSNI is to encourage partners to launch joint experimental research projects. IRSN is taking part in 24 ongoing projects and manages three of them – ESTER, CIP and FAIR – and conducts experiments for these in its facilities.
Thus, the first semi-integral test of the ESTER program was successfully carried out at the beginning of 2023 on the CHIP (chemistry of iodine in the primary cooling system) test bench in Cadarache suitable for these new experiments. This program is aimed at better identifying conditions that may contribute to deferred emissions due to fission product deposits on the surfaces of an installation during a major accident.
Following the CIP1-2B test conducted at the end of 2022, the 5th test of the CABRI international program (CIP) was carried out by the IRSN and CEA teams on April 24, 2023, at the CABRI facility in Cadarache now equipped with a “water loop”, representative of the thermo-hydraulic conditions of a pressurized water reactor (PWR). Mostly financed by IRSN, this program studies the behavior of nuclear fuel rods in PWR reactors in an accidental power excursion situation.
On June 1st, 2023, the NEA/OECD launched a new five-year program called FAIR. Focusing on fire risks, it brings together some twenty organizations. The experimental campaigns will be conducted by IRSN on its Galaxie experimental platform in Cadarache.
The only one of its kind, IRSN’s EPICUR irradiator at Cadarache can be used to study the behavior of iodine and different types of materials during a major accident in a nuclear reactor. Its specificity is to be coupled to a test loop making it possible to recreate the conditions representative of such an accident. The cobalt-60 sources were replaced in the first quarter of 2023, allowing EPICUR tests to continue.
RSNR projects:
positive report
In the closing meetings for the RSNR projects held in 2022–2023, the French National Research Agency congratulated IRSN for the scientific results obtained, the quality of project management and compliance with commitments. These projects, launched under the Investments in the Future Program, were part of the consideration of the factors and consequences of the Fukushima-Daiichi accident and, for the projects managed by the Institute, were aimed at acquiring new knowledge about serious accidents and their radiological consequences.
Key elements of research, experimental and software platforms require substantial investments to meet the increasingly specific needs of scientific projects.
Inaugurated on February 3, 2023, the MACUMBA installation of the MISTRAL platform at Saclay will be able to accommodate different types of models of reinforced concrete structures encountered in nuclear facilities (PWR containment structure, walls representative of ventilated areas of laboratories and plants) in order to subject them to controlled mechanical and thermal stresses. COBRA is the first research program conducted at this facility. Its purpose is to estimate the dry air/air-steam leakage rate and the retention of aerosols in the wall of a containment structure of a 1300 MWe pressurized water reactor, based on its state of cracking during a serious accident.
In order to maximize the use of its experimental and software platforms, the Institute is participating in the OFFERR project to enhance these facilities at the European level. Bringing together 17 partners, OFFERR aims to create a network of experimental research infrastructures, to facilitate access to them for European scientists and students, and to contribute to the development of research projects drawing on these facilities. In April 2023, OFFERR published its first call for research projects using one of the 178 installations listed in its database.
In order to acquire knowledge on the behavior in accident situations of a new generation of more accident-tolerant fuels (ATF), likely to be deployed in the future in French nuclear power stations, IRSN is already investing in new international research programs.
Following the Fukushima-Daiichi accident, manufacturers launched the development of new types of fuels with the aim of providing greater resilience in accidents. The changes made concern both the claddings containing the fuel pellets – in particular to limit oxidation and deformation phenomena in the event of a loss of coolant – and the pellets, in order to ensure better retention of the fission products and to reduce mechanical stresses on the cladding.
The Institute is thus associated with research programs, conducted under the auspices of the OECD Nuclear Energy Agency, including test campaigns aimed at studying the behavior of ATFs in configurations representative of reactor accident situations. IRSN is also preparing to carry out experiments on ATF claddings made available by Framatome, EDF’s supplier. The results of this work will enable IRSN to develop and validate specific models to simulate the behavior of these future fuels.
Signed on January 19, 2023, the framework agreement between IRSN and the National Institute for Industrial Environment and Risks (Ineris) aims to reinforce the actions carried out by the two institutes in the area of risks and for the preservation of biodiversity and health.
Long-standing partners, Ineris and IRSN – key players in chemical and industrial risks for the first, and radiological and nuclear risks for the second – play a complementary role with the public authorities. The decision to strengthen their collaboration responds to the wish to coordinate their resources to address two major challenges:
It targets four areas more specifically:
Concluded for five years, the agreement will enable IRSN and Ineris to share strategic and forward-looking thinking, pool their resources and strengthen the effectiveness of the support provided to public authorities.
Launched in May 2023 under the France 2030 plan, the IRiMa program aims to develop a science of risks that can contribute to strengthening France’s resilience in the context of global changes. Its uniqueness and strength are to bring together all the communities potentially concerned: geosciences and natural risks; technological and nuclear risks; human and social sciences.
The work carried out by IRSN is aimed at better understanding the environmental impact of exposure to ionizing radiation, in order to preserve both biodiversity and the benefits that humans derive from it.
In 2023, IRSN conducted field research as part of its BEERAD and KERO projects, with the aim of assessing the consequences of radioactive discharges from the Fukushima-Daiichi accident. The BEERAD project concerned the effects of ionizing radiation on bees, investigating both their health and their ability to maintain their pollination and honey production functions. As for the KERO project, its aim was studying the consequences of radioactive contamination on wildlife, focusing on a model species: the tree frog Dryophytes japonicus.
The work carried out aims to assess the health of ecosystems, using diverse and complementary approaches. Ecosystem services (the benefits humans derive from ecosystems) are one component of this state of health. Their utility as an indicator of the state of biodiversity was highlighted in a recent publication by the Institute. In the same way, IRSN is participating in the DECORHONE project to identify the ecosystem services provided in the Rhone corridor, in order to have an inventory before studying the impact of ionizing radiation.
IRSN conducts epidemiological studies to study the effects of exposure to low doses of ionizing radiation, in order to improve prevention and verify the soundness of the radiation protection system.
The EPI-CT study published in the Lancet Oncology and Nature Medicine journals confirmed an excessive risk of malignant brain tumors and hematologic malignancies in children and adolescents after CT scans. These cancer risks increase with the dose administered, but remain very low in view of the diagnostic benefit of CT scans.
Similarly, the INWORKS study published in the British Medical Journal confirmed a relationship between the risk of death due to cancer and the repeated exposure to low doses of ionizing radiation among workers in the nuclear industry.
In addition, in the Journal of Radiological Protection IRSN published its view on the validity of the Linear No Threshold (LNT) model. Based on a summary of the state of recent knowledge in radiobiology and epidemiology, IRSN concluded that the LNT model is suitable for estimating the risk of cancer associated with exposure to ionizing radiation in support of the radiation protection system.
Two research projects were launched in 2023 at IRSN. “Watch your heaRT” is aimed at assessing the risk of cardiac arrhythmias in the five years following radiotherapy for breast cancer. Funded by ANSES, “BECOME” investigates the risk of radiation-induced brain cancer among medical professionals.
