ASN Report 2023

Note that as from 1 January 2025, pursuant to the new Articles R. 4451‑62 and R. 4451‑63 of the Labour Code, the utilisation of an industrial radiology device containing one or more high‑activity sealed sources in a work zone will require at least two of the owner company’s employees to hold the CAMARI certificate (see point 5). The inspectors also noted that the efforts made by the companies to train newly‑arrived classified workers had been maintained. Consequently, this information was duly dispensed to the new staff in 94% of the inspected facilities concerned in 2023. Furthermore, although the inspections found no non‑compliance with the licences issued by ASN concerning radionuclides or maximum activity held, companies must nevertheless be more thorough in checking that their inventory of sealed radioactive sources is consistent with the national inventory held by IRSN (deviation level of 8% observed) Lastly, the companies must devote considerable efforts not only to defining an exhaustive programme of verifications as required by the Labour Code and implementing it correctly, but also to correcting the nonconformities found during these verifications and ensuring the traceability of the corrections made (deviations noted in more than one inspection out of three). Despite a slight improvement in 2023, ASN still considers that the deviations observed in cordoning off the work zones on worksites (found in virtually one inspection in four) give cause for concern. ASN underlines that the lack of preparation and cooperation between the ordering customers and the radiography contractors before starting worksites is one of the causes of 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 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 must not be taken for granted. ASN keeps a watchful eye on accidents occurring abroad which have sometimes had serious effects. Over the last few years, examples brought to ASN’s attention confirming the risks to which operators can be exposed as a result of inappropriate actions, include: • In 2023 in Germany, a radiologist was exposed to a dose of 71.5 millisieverts (mSv) after entering a facility when the electrical device emitting ionising radiation used in that facility was still in operation. The causes of the event are still being investigated. • In 2023 in the United States, a trainee radiographer was exposed several times to a source of iridium‑192 on a worksite when carrying out various operations (replacement of the film, movement of the guide tube) while the source was still positioned in the irradiation endpiece due to the detachment of the source holder. In the course of this incident, several radiation protection barriers were not observed, notably by the lack of supervision of the trainee radiographer (particularly during the source holder connection phase), failure to wear a dosimeter or use a radiation meter and verify that the source had returned properly into the projector (check of the indicator light, measurements, etc.). The trainee radiographer only noticed the problem when the guide tube became disconnected from the source projector. The dosimetric reconstruction (as no dosimeter was worn) gave an effective received dose estimate of 75 mSv and 258 mSv at the extremities. • In 2022 in the United States, a team of three operators of a non‑destructive testing company was performing gamma radiography work. One of the operators was close to the cobalt‑60 source when it was ejected by his colleague who did not have direct visual contact with him. Given the very noisy environment of the worksite, the operator did not hear the alarm of his monitoring devices and was exposed to a dose of 55 mSvfor about one minute. • In 2022 in Belgium, a radiographer was exposed (14 mSv whole body, extremity dose not specified) to a selenium‑75 source for a short period (60 to 90 seconds) when he tried to disconnect the device collimator while the source was still present in it. The alarm of his active dosimeter did not function because its battery was discharged; furthermore, the operator was not wearing his radiation meter. It was the triggering of his assistant’s active dosimeter alarm when he approached the source that signalled the incident. • In 2022 in Hungary, an operator was exposed to about 134 mSv when handling the collimator and the guide tube, as the selenium‑75 source was not retracted into the safe position in the projector. • 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 International Nuclear and Radiological Event Scale (INES). • 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. • 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 sieverts (Sv). The event was rated level 2 on the INES scale. • 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. The data for earlier incidents can be consulted in the previous issues of this annual report, which are available on asn.fr, under the headings “ASN informs”, “Publications”, “ASN Reports”. GAMMA RADIOGRAPHY: SERIOUS ACCIDENTS ABROAD ASN Report on the state of nuclear safety and radiation protection in France in 2023 257 • 08 • Sources of ionising radiation and their industrial, veterinary and research applications 08 05 15 11 04 14 06 07 13 AP 03 10 02 09 12 01

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