ASN Report 2020

the 2019 results are not directly comparable with those of 2018 and 2017. Nevertheless, in order to establish trends, the results for the years 2015 and 2016 have been retroactively reassessed applying the new methodological approach (see Table 3). Tables 1 and 2 present, per area of activity and for the year 2019, the breakdown of the populations monitored, the collective dose (the collective dose is the sum of the individual doses received by a given group of persons), and the number of times the annual limit of 20 mSv was exceeded. They show a large disparity in the breakdown of doses depending on the sector. For example, the medical and veterinary activities sector, which comprises a significant share of the population monitored (58%), accounts for only 8% of the collective dose; on the other hand, the civil nuclear industry, which represents just 22% of the headcount, accounts for 40% of the collective dose and the sector concerned by exposure to natural radioactivity, which represents only 6.4% of the total headcount, accounts for 47.7% of the collective dose. The industrial sector for its part represents 4% of the headcount and accounts for 2.3% of the collective dose. Table 3 shows that the total number of workers monitored by external passive dosimetry has increased by about 1% per year since 2015. In 2019, the collective dose (for all areas combined) reached 112.31 man-Sv, a value that has increased by nearly 8% compared with 2018, whereas the average individual dose has increased by 7%. These increases are primarily linked to the increase in the amount of maintenance work in the nuclear sector and the increase in doses received by flight crew. In 2019, five cases exceeding the regulatory effective dose limit of 20 mSv were registered (see Diagram 2). Four of them concerned professionals in the medical sector while the fifth concerned a worker in the “others: private inspection and oversight organisations” sector. It should nevertheless be noted that out of these five cases of exceeding the effective dose limit, three were kept by default as there was no feedback from the occupational physician on the conclusions of the inquiry. With regard to the dosimetry of the extremities (fingers and wrist), 28,623 workers were monitored in 2019 (i.e. 7% of the total number of persons monitored). Out of all the persons monitored, there was one case – in the medical sector – where the 500 mSv regulatory equivalent dose limit at the extremities was exceeded (552.17 mSv). Furthermore, 4,830 workers were subject to monitoring of lens of the eye exposure. This represents an increase in monitoring of more than 38% compared with 2018. This significant increase is linked to the arrival on the market of several new dosimeters suited to this type of measurement. Eight workers (in the medical radiology sector) received an equivalent dose or more than 20 mSv. The maximum recorded dose is 34.74 mSv. This value should be compared with the future regulatory dose limit for the lens of the eye of 20 mSv/year as from 2023. To conclude, as in the preceding years, the Assessment of dosimetric monitoring of worker external exposure in 2019 published by the IRSN in October 2020, shows the overall effectiveness of the prevention system introduced in facilities where sources of ionising radiation are used, because for 91% of the population monitored the annual dose remained lower than 1 mSv (effective annual dose limit for the public due to nuclear activities). Exceeding the regulatory limit values remains exceptional (five cases exceeding the annual limit of 20 mSv). Monitoring of exposure of the lens of the eye with, for this tissue, compliance with the new limit, constitutes the main objective of radiation protection in the immediate years and more specifically in the area of fluoroscopy-guided interventional medical practices. 3.1.2 Worker exposure to natural radioactivity Exposure to radioactive substances of natural origin and to radon of geological origin Worker exposure to radioactive substances of natural origin results either from the ingestion of dust from materials containing large amounts of radionuclides (phosphates, metal ores), or from the inhalation of radon formed by uranium decay (poorly ventilated warehouses, thermal baths) or from external exposure due to industrial process deposits (scale forming in piping for example). The results of studies carried out in France between 2005 and 2009, published by ASN in January 2010, along with the studies published up until 2018, show that 85% of the doses received by Sources and routes of exposure to ionising radiation Inhalation External irradiation Skin contamination External irradiation Internal contamination by inhalation of radioactive substances Skin contamination Ingestion External irradiation Skin contamination and involuntary ingestion External irradiation Internal contamination through ingestion of contaminated foodstuffs Skin contamination and involuntary ingestion 110 ASN Report on the state of nuclear safety and radiation protection in France in 2020 01 – NUCLEAR ACTIVITIES: IONISING RADIATION AND HEALTH AND ENVIRONMENTAL RISKS