4 // Manufacturers and distributors of radioactive sources and their oversight by ASN 4.1 The issues and implications The aim of ASN oversight of the suppliers of radioactive sources or devices containing them is to ensure the radiation protection of the future users. It is based on the technical examination of the devices and sources with respect to operating safety and radiation protection conditions during future utilisation and maintenance. It also allows the tracking of source transfers and the recovery and disposal of disused or end-of-life sources. Source suppliers also play a teaching role with respect to users. At present, only the suppliers of sealed radioactive sources (or devices containing them) and of unsealed radioactive sources are regulated in France (see point 2.3.1). ASN lists slightly over 150 suppliers with safety significant business, including 35 low and medium-energy cyclotrons which are currently licensed under the Public Health Code in France. 4.2 Cyclotrons Functioning As at 31 December 2021, 4 cyclotrons were “on standby” and 31 were in operation, including 1 in the test phase. Among the 30 devices in nominal operation, 16 are used exclusively for the daily production of radiopharmaceuticals, 7 are used for research purposes and 7 for both production and research. The commissioning of 4 cyclotrons is planned for 2022 and 2023, with two of them expected to start functioning for research purposes in 2022. The assessment of radiation protection in facilities using cyclotrons ASN has been exercising its oversight in this area since early 2010. Each new facility or any major modification of an existing facility undergoes an extensive examination by ASN. The main radiation protection issues concerning these facilities must be considered as of the design stage. Application of the relevant standards, in particular standard NF M 62105 “Industrial accelerators: installations”, ISO 10648-2 “Containment enclosures” and ISO 17873 “Ventilation systems for nuclear installations”, guar– antees safe utilisation of the equipment and brings a significant reduction in risks. Facilities that have a cyclotron used to produce radionuclides and products containing radionuclides are subject to gaseous effluent discharge limits specified in their license. The discharge levels depend on the frequency and types of production involved. Systems for filtering and trapping the gaseous effluents are installed in the production enclosures and in the facilities’ ventilation systems in order to minimise the activity discharged at the stack outlet. Some licensees have also installed –as close as possible to the shielded enclosures– systems for collecting and storing the gases to let them decay before being discharged, bringing a substantial reduction in the activities discharged into the environment. Consequently, the discharged activity levels and the short halflife of the radionuclides discharged in gaseous effluents mean there is no significant impact on the public or the environment. ASN, jointly with IRSN, continued a study they began in 2016 on the gaseous discharges into the environment from these facilities. The conclusions of the first step, which involved both IRSN and the licensees, served to establish in 2018 general principles on managing gaseous effluent discharges, the key points of which will be taken up in a draft regulatory text. Alongside this, new assessments of the impacts of discharges from the facilities situated near residential areas have been carried out, using for some facilities modelling tools that are better suited to near-field studies. To complement this, IRSN acquired a computing tool in 2020 that provides a more accurate estimate of the radiological impacts by better modelling the dispersion of discharges in the immediate vicinity of the site and can perform, if necessary, counter-assessments of the studies provided by the licensees. Lastly, on 23 September 2021, ASN and IRSN held a meeting to present to the licensees of the 31 cyclotrons in operation, in metropolitan France and overseas, the new guidelines for developing the impact assessment to be included in a license application. This document details the different steps of an impact assessment, particularly the characterisation of the source term (discharges), a precise description of the local environment and of the transfers to the environment, emphasising the importance of the choice of dispersion calculation method and the final dose assessment. It will be widely disseminated to the profession in 2022. ASN performs about ten inspections at facilities of this type each year. Eight sites were inspected in 2021, including one currently being set up. Radiation protection, safety of use and the correct operation of cyclotrons and production platforms receive particular attention during the inspections. The scope of the inspections performed includes, in addition to the aspects relating to radiation protection, the management of abnormal events, monitoring and maintenance of the production equipment, inspection of the surveillance and control systems as well as the gaseous discharge results and the management of waste and liquid effluents. The seven inspected facilities in operation have a satisfactory radiation protection organisation (at least one RPA and one person holding the CAMARI qualification), and a good grasp of the regulations, as much from the viewpoint of worker protection as for the verification of equipment and compliance with the provisions applicable to source, waste and effluent management. One inspected facility, however, exceeded the authorised limit for atmospheric discharges, resulting in it being served a formal compliance notice. Lastly, national action plans are put into place by the licensees of two major French radiopharmaceutical production groups and are monitored by ASN to ensure continuous improvement of radiation protection and safety in these facilities. Six ESRs were reported by the cyclotron licensees in 2021. None of these events led to significant exposure of workers or the public. Two ESRs concerned the delivery of a higher activity than the maximum authorised for the customer, chiefly linked to inconsistencies in the computing aid. Two other ESRs concerned the contamination (with no radiological consequences) of an operator’s hand when disconnecting a capillary tube from a flask and the handling of activity levels exceeding those effectively authorised. Lastly, two facilities reported exceeding of their annual limit for discharges of radioactive gaseous effluents. One of the incidents occurred in a one-off manner during the tests phases prior to putting the cyclotron into routine operation, while the other concerned a fluorine‑18 production site where the discharge filtration system was faulty for several months and exceeding the annual limit was not detected immediately. In both cases measures were taken to bring the discharges back within the authorised limits. 256 ASN Report on the state of nuclear safety and radiation protection in France in 2021 08 – SOURCES OF IONISING RADIATION AND THEIR INDUSTRIAL, VETERINARY AND RESEARCH APPLICATIONS
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