In the field of research, two synchrotron radiation production facilities can be mentioned in France: the European Synchrotron Radiation Facility (ESRF) in Grenoble, and the Optimised Source of Intermediate Energy Light of the Lure Laboratory (Soleil) synchrotron in Gif-sur-Yvette. Particle accelerators have been used for several years now in France to fight fraud and large-scale international trafficking. This technology, which the operators consider effective, must however be used under certain specific conditions, in order to comply with the radiation protection rules applicable to workers and the public, in particular: ∙ a ban on activation of construction products, consumer goods and foodstuffs as specified by Article R. 1333-2 of the Public Health Code, by ensuring that the maximum energy of the particles emitted by the accelerators used excludes any risk of activation of the materials being verified; ∙ a ban on the use of ionising radiation on the human body for purposes other than medical; ∙ the setting up of procedures to ensure that the checks con– ducted on the goods or transport vehicles do not lead to accidental exposure of workers or other individuals. The use of ionising technologies to seek out illegal immigrants in transport vehicles is prohibited in France. During customs in– spections of trucks using tomographic techniques, for example, the drivers must be kept away from the vehicle and other checks must be performed prior to irradiation to detect the presence of any illegal immigrants, in order to avoid unjustified exposure of people during the inspection. 3.3.2 The radiation protection situation The use of particle accelerators presents significant radiation exposure risks for the workers; ASN is particularly attentive to these facilities and therefore inspects them regularly. In 2018, ASN put in place inspection indicators specific to particle accelerators, which now enable the radiation protection situation in this sector of activity to be better assessed on the national scale. Between 2018 and 2021, 50 facilities equipped with these devices were inspected by ASN, 13 of them in 2021. ASN considers the radiation protection situation in the facilities using these devices to be satisfactory on the whole. In effect, the key requirements for conducting this activity with a satisfactory level of radiation protection (organisation of radiation protection, informing and training, technical verifications, radiological zoning and design of the premises in which these devices are used) are appropriately implemented by the large majority of the licensees concerned. GAMMA RADIOGRAPHY: SERIOUS ACCIDENTS ABROAD The number and consequences of gamma radiography accidents in France have remained limited since March 1979, when a worker had to have a leg amputated after having picked up a 518 gigabecquerels (GBq) source of iridium-192 and put it in his pocket. This incident had led to a tightening of the regulations in effect at the time. This situation must nevertheless not be taken for granted and continued vigilance is required. ASN keeps a watchful eye on accidents occurring abroad which have sometimes had serious effects. Over the last ten years, examples brought to ASN’s attention confirming the risks to which operators can be exposed as a result of inappropriate actions, include: ཛྷ In 2021 in the USA, an employee of a non-destructive testing company was exposed to a dose of 70 mSv (whole body) while carrying out gamma radiography exposures within a dedicated facility. The procedures in force at the time of this accident authorised the operator to be present inside the facility even when the source was in the irradiation position. An employee of another non-destructive testing company was exposed to a dose of 93 mSv (whole body) when manipulating a defective gamma radiography projector whose source was not in the safe position. These two events were rated level 2 on the INES scale. ཛྷ In 2021 in Serbia, an iridium-192 source became detached from the remote control cable during an outdoor non-destructive test. The two operators did not check that the source had returned to the safe position at the end of the inspection and did not notice its absence until they got back to their company base. The source was found the next day after the intervention of a specialised laboratory. The two operators were exposed to doses of 451 mSv and 960 mSv. ཛྷ In 2021 in Spain, an employee of a non-destructive testing company was exposed after entering a gamma radiography bunker when the iridium-192 source was not in the safe position (source jammed). The passive dosimeter of the first employee indicated a dose of about 70 mSv, and that of the second about 3 Sv. The event was rated level 2 on the INES scale. ཛྷ In 2020 in the United States, a radiographer and two assistant-radiographers performing non-destructive tests in an asphalt production unit were exposed to whole body doses of 636, 104 and 26 mSv respectively while attempting to reintroduce the source into the gamma ray projector after the guide tube had been crushed by a support which fell from a storage tank. The event was rated level 2 on the INES scale. ཛྷ In 2019 in Spain, an employee of a non-destructive testing company was exposed to about 200 mSv (whole body) by entering a gamma radiography bunker when the iridium-192 source was not in the safe position. The door-opening slaving system for prohibiting access to the bunker during the emission of ionising radiation, did not function due to the failure of the dose rate measuring system. The event was rated level 2 on the INES scale. A similar accident happened the same year in Germany: two employees were exposed to 100 and 30 mSv respectively (whole body) when they entered a gamma radiography bunker when the iridium-192 source was not in the safe position and the radiological environment had not been checked. The event was rated level 2 on the INES scale. ཛྷ In 2016 in Turkey, the operators had apparently not verified that the source had returned to the safe position after using a gamma ray projector. A 16-year old adolescent found the source the day after the inspection and took it home where several persons said they handled it. 20 people in all were reportedly exposed, with most severely exposed person reportedly receiving a dose of 1 gray (Gy). The event was rated level 2 on the INES scale. The data from before 2016 can be consulted in the previous issues of this annual report. The issues are available at asn.fr, under the headings “ASN informs”, “Publications”, “ASN annual reports”. 250 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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