Industrial X‑ray radiography Industrial X‑ray radiography devices are very varied, ranging from fixed devices (integrated in a facility of very variable size) to mobile devices which can be used equally well in worksite conditions as in a facility. In application of the principle of optimisation, they must be used instead of gamma radiography devices when the conditions so permit because they do not make use of a radioactive source. Apart from non‑destructive inspection, these devices can also be used for more specific and therefore rarer purposes, such as radiography for the restoration of musical instruments or paintings, archaeological study of mummies or the analysis of fossils. 3.1.2 Evaluation of the radiation protection situation Industrial radiography activities are high‑risk activities which have been an inspection priority for ASN for several years now. In 2023, ASN conducted 124 inspections in this area, slightly fewer than in the preceding years. Among these inspections, 43 were unannounced inspections on worksites which also include night work. The on‑line notification of worksite schedules for industrial radiography companies put in place by ASN in 2014 facilitates the planning of these inspections. ASN notes that virtually all the companies concerned routinely use this system for giving notification of their worksites. The reliability of the information transmitted however, is still very varied. The points to improve include: ∙ the updating of schedules when they are changed or cancelled; ∙ the accuracy of the worksite location information (not to be confused with the address of the ordering company); ∙ the completeness of the worksite notification; ∙ the identification of the device used on the worksite (gamma radiography or X‑ray device). ASN finds that the large majority of companies maintained the necessary rigour to meet the regulatory requirements with respect to the appointing of a Radiation Protection Advisor (RPA), worker dose monitoring and radiological zoning of their facilities (less than 10% non‑compliance observed). Furthermore, the inspectors noted that the frequency of maintenance of gamma radiography devices on the whole complies with regulations (no non‑compliance found for projectors, 7% non‑compliance found for accessories). Similarly, nearly all the operators inspected by ASN held, when it was necessary, the certificate of competence in the use of industrial radiology devices (CAMARI) required by Article R. 4451‑61 of the Labour Code (only one case of non‑compliance observed, concerning use in a facility). Schematic diagram of the functioning of a gamma ray projector The use of selenium‑75 in gamma radiography has been authorised in France since 2006. Implemented in the same devices as those functioning with iridium‑192, selenium‑75 offers significant radiation protection advantages. This is because the equivalent dose rates are about 55 millisieverts per hour and per terabecquerel (mSv/h/TBq) one metre from the selenium‑75 source, as opposed to 130 mSv/h/TBq for iridium‑192. Yet it can be used in place of iridium‑192 in numerous industrial fields, especially the petrochemical or boilermaking industry, and it enables the cordoned‑off safety area to be significantly reduced and facilitates intervention in the event of an incident. In France, about 15% of the devices are equipped with selenium‑75 sources. The use of selenium‑75 has stagnated over the last few years and even decreased in 2023 (20% in 2022). More specifically, the current geopolitical context (sanctions against Russia because of the war in Ukraine) is resulting in a restructuring of the global supply chain for gamma radiography sources, accompanied in particular by delays in delivery. Nevertheless, diverse procurement routes have been set up by the source suppliers in the last few years, and new ones are being explored. ASN therefore still encourages the use of selenium‑75 whenever possible. SELENIUM‑75 GAMMA RADIOGRAPHY 256 ASN Report on the state of nuclear safety and radiation protection in France in 2023 • 08 • Sources of ionising radiation and their industrial, veterinary and research applications
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