ASN therefore considers that the conditions of storage and removal of sealed radioactive sources at end of life and of radioactive waste and effluents remain the main difficulties encountered by the research units. This situation is particularly pronounced in universities which have historically stored their expired/disused sealed radioactive sources and their waste contaminated by radionuclides, sometimes over very long periods of time rather than disposing of them regularly, which today poses two main problems: ∙ in view of their diversity, the radioactive waste and expired/ disused radioactive sources cannot be further managed without first being precisely identified and characterised; ∙ this disposition, to which must be added prior characterisation where applicable, represents a significant financial cost which has often been neither foreseen nor budgeted for. The technical, economic and regulatory difficulties concerning the disposal of old sealed sources persist. In 2022, faced with the persistent failure of one university to characterise and seek appropriate disposal routes for its sealed radioactive sources at end of life and for its waste, ASN issued a compliance notice; the university has now started the procedures necessary to remedy this legacy situation. At the same time, ASN has put in place tightened monitoring of certain research units with regard to management of sources and waste or the compliance with their licenses. With regard to occupational radiation protection, the Order of 23 October 2020 on the radiation protection verifications of equipment and workplaces gives more responsibilities to the radiation protection advisors in this respect. A few deviations are to be noted concerning the failure to fully apply the periodic verifications programme (verifications incomplete or lacking) or to carry out the verifications; the situation has nevertheless been improving since 2021. Particular attention shall continue to be paid to this point in future inspections. Lastly, in nearly 85% of the sites inspected, the periodic verification of the calibration of the radiation protection instrumentation is carried out at the proper frequency and the instrumentation is in good working order. 76% of the inspected sites have systems for recording and analysing adverse events and ESR. In 2022, ASN registered 29 ESRs concerning research activities (see Graph 12), of which only one was rated level 1 on the INES scale. Three-quarters of the reported ESRs are essentially of two types: ∙ discovery of sources (59%); ∙ slight contamination of the work environment during the handling of sources (24%). The five other reported events are of diverse origins (loss or theft of sources, jamming of source in a gamma ray projector (see point 3.1.1) used for research purposes, contamination of a dosimeter due to incorrect stowage and possessing radionuclides without a license). The discoveries of sources can be explained in particular by poor overall traceability: this often results from the failure to take action to dispose of them when laboratories cease their activity, or from irregular and incomplete keeping of source inventories, as mentioned above. These chance discoveries occurred most often during fitting out works in basement rooms or rooms which have not been used for several years. With regard to the cases of work environment contamination, the main identified causes are linked to the presence of contamination on the ground as a result of manipulations of unsealed sources, the malfunctioning of a liquid effluent management system and the loss of integrity of a sealed radioactive source. ASN is also continuing its collaboration with the General Inspectorate of the National Education and Research Administration, which has competence for labour inspection in the public research sector. An agreement signed in 2014 provides for mutual information sharing to improve the effectiveness and complementarity of the inspections. SYNCHROTRONS Belonging to the same family of circular particle accelerators as the cyclotrons (see point 4.2), the synchrotron, which is much larger, can attain energy levels of several gigaelectronvolts by using successive accelerators. Owing to the low mass of the particles (generally electrons) the acceleration created by the curvature of their trajectory in a storage ring, produces an electromagnetic wave when the speeds achieved become relativistic: this is synchrotron radiation. This radiation is collected at various locations called beam lines and is used to conduct scientific experiments. RESEARCH ACTIVITIES The use of ionising radiation in research activities extends to various fields such as medical research, molecular biology, the agri-food industry, materials characterisation, etc. It primarily involves the use of unsealed sources (iodine-125, phosphorous-32, phosphorous-33, sulphur-35, tritium-3, carbon-14, etc.). Sealed sources (barium-133, nickel-63, caesium-137, cobalt-60, etc.) are also used in gas chromatographs or scintillation counters or, with higher-activity sources, in irradiators. X‑ray generators rays are used for X‑ray fluorescence or X‑ray diffraction spectrum analyses. The use of scanners for small animals (cancer research) in research laboratories and faculties of medicine should also be noted. Particle accelerators are used in research into matter or for the manufacture of radionuclides. ASN Report on the state of nuclear safety and radiation protection in France in 2022 259 08 • 08 • Sources of ionising radiation and their industrial, veterinary and research applications 01 07 13 AP 04 10 06 12 14 03 09 05 11 02
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