Nuclear research or industrial facilities differ from the Basic Nuclear Installations (BNIs) involved directly in the generation of electricity (nuclear power reactors and “fuel cycle” facilities) or waste management. Traditionally, most of these BNIs are operated by the Alternative Energies and Atomic Energy Commission (CEA), but also by other research organisations (for example the Laue-Langevin Institute (ILL), the ITER international organisation and the National Large Heavy Ion Accelerator – Ganil) or by industrial firms (for instance CIS bio international, Steris and Ionisos, which operate facilities producing radiopharmaceuticals, or industrial irradiators). 1 Research facilities, laboratories and other facilities in France 1. The use of radionuclides offers medical analysis and treatment possibilities: for diagnosing cancers using scintigraphy and tomography, allowing advanced examinations of functioning organs, or for treating tumours by radiotherapy, which uses the radiation from radionuclides to destroy the cancerous cells (see chapter 7). 1.1 Research reactors The purpose of research reactors is to contribute to scientific and technological research and to improve the operation of the Nuclear Power Plants (NPPs). Some of these facilities also produce radionuclides(1) for medical uses. They are facilities in which a chain reaction is created and sustained, to produce a neutron flux of varying density, used primarily for scientific experimentation purposes. Unlike in NPPs, the energy produced by research reactors is not used but simply removed by cooling. The quantities of radioactive substances used are smaller than in nuclear power reactors. An overview of the various types of research reactors present in France and the main corresponding risks is presented below. In their design, these reactors take account of reference accidents, both core melt “under water” (failure of the cooling system) and core melt “in air” (after uncovering of the core or during handling). They also take account of accidents specific to the particular design of certain research reactors. Neutron flux reactors Neutron flux reactors are pool-type reactors. They are mainly designed for fundamental research (solid physics, molecular physico-chemistry, biochemistry, etc.), using the neutron diffraction method to study matter. The neutrons are produced in the reactor, at different energy levels and are captured by channels in the reactor before being routed to experimentation areas. In France, there is now only one neutron beam reactor in service: the High-Flux Reactor (RHF – BNI 67) operated by the ILL in Grenoble (rated power limited to 58 Megawatts thermal (MWth). The RHF operates in cycles of about 50 to 100 days. The main safety issues are reactivity control, cooling and containment. In 2024, ASN authorised works to improve the safety of the facility which were defined during the last periodic safety review, in particular the renovation of the polar crane in the reactor building, reinforcement of fire protection and removal of the residual tritium from the facility. The ILL started these works following the long outage of the facility which began in July 2024. The Orphée reactor (BNI 101), operated by CEA in Saclay (rated power limited to 14 MWth), was finally shut down at the end of 2019. “Test” reactors The “test” reactors are pool-type reactors. They are designed to study accident situations. They are able to reproduce certain accidents postulated in the safety case of nuclear power reactors in a controlled manner and on a small scale and gain a clearer understanding of the evolution of physical parameters during accidents. In France there is one “test” reactor in service subject to the oversight of the French Nuclear Safety Authority (ASN): the Cabri reactor (BNI 24) operated by CEA in Cadarache. The reactor, whose power is limited to 25 MWth, can produce the neutron flux needed for the experiments. The safety issues are similar to those of the other reactors: controlling the reactivity of the driver core, cooling to remove heat and containment of the radioactive substances in the fuel rods making up the core. Modifications were made to the facility so that it could run new research programmes to study the behaviour of high burn-up fraction fuel during reactivity insertion accident situations. Reactor divergence in its new configuration was authorised in 2015. On 30 January 2018, ASN authorised the first active experimental test of the facility’s pressurised water loop after major renovation work. The Cabri “test” reactor, the design of which was modified so that it could also carry out object irradiation experimental programmes, was licensed for this type of use by a Decree of 2 August 2022. The test programmes (Cabri International Programmes – CIP) and electronic component irradiation tests continued in 2024. Alongside these tests in 2024, ASN authorised the underwater repair of the hodoscope, which should be carried out at the end of the ongoing programme of tests, by the end of 2025. ASN checks the implementation of the actions undertaken further to the conclusions of the last periodic safety review of the facility, particularly regarding the improvement of the measures to prevent fire risks and risks associated with handling operations. Irradiation reactors The irradiation reactors are pool-type reactors. They are used to study the physical phenomena linked to the irradiation of materials and fuels, as well as their behaviour. As the neutron fluxes obtained by these facilities are more powerful than those in a Pressurised Water Reactor (PWR) type nuclear power reactor, the experiments enable ageing studies to be performed on the materials and components subjected to a high neutron flux. After irradiation, the samples undergo destructive examination, notably in the research laboratories, in order to fully characterise the effects of irradiation. They are thus an important tool for the qualification of materials subjected to a neutron flux. ASN Report on the state of nuclear safety and radiation protection in France in 2024 345 Nuclear research and miscellaneous industrial facilities 13 02 03 04 05 06 07 08 09 10 11 12 01 14 15 AP
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