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 monitoring of workers exposed to ionising radiation in France in 2020, published by IRSN in June 2021, shows the overall effectiveness of the prevention system introduced in facilities where sources of ionising radiation are used, because for 94% of the population monitored, the annual dose remained below 1 mSv (effective annual dose limit for the public due to nuclear activities). Exceeding the regulatory limit values remains the exception (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 the studies conducted in France between 2005 and 2009, published by ASN in January 2010, and the studies published in 2018, show that 85% of the doses received by workers in the industries concerned remain below 1 mSv/year. The industrial sectors in which worker exposure is liable to exceed 1 mSv/year are the following: titanium ore processing, heating systems and recycling of refractory ceramics, maintenance of parts comprising thorium alloys in the aeronautical sector, chemical processing of zircon ore, mechanical transformation and utilisation of zircon and processing of rare earths. In 2020, the individual monitoring of worker exposure in industrial activities leading to exposure to radioactive substances of natural origin or to radon of geological origin concerned about 450 workers, of whom 21 were exposed to more than 1 mSv (internal exposure to the natural radionuclides of the uranium and thorium decay chains). Flight crew exposure to cosmic radiation Airline flight crews and certain frequent flyers are exposed to significant doses owing to the altitude and the intensity of cosmic radiation at high altitude. These doses can exceed 1 mSv/year. Since 1 July 2014, IRSN calculates the individual doses for civil flight personnel using the SievertPN application, on the basis of the flight and personnel presence data provided by the airlines. These data are subsequently transmitted to Siseri, the French national worker dosimetry registry. As at 31 December 2020, SievertPN had transmitted to Siseri all the flight crew doses for 12 airlines having subscribed to the system, giving a total of 21,949 flight crew members monitored by this system. In 2020, nearly 55% of the individual annual doses were below 1 mSv and 45% of the individual annual doses were between 1 mSv and 5 mSv. The maximum individual annual dose was 4.17 mSv. The collective dose in 2020 fell by 58% compared with 2019, whereas it had been increasing regularly over the last few years. This reduction can be explained by the health crisis which caused a significant drop in air traffic. 3.2 Doses received by the population 3.2.1 Exposure of the population as a result of nuclear activities The automated monitoring networks managed nationwide by IRSN (Téléray, Hydrotéléray and Téléhydro networks) offer real-time monitoring of environmental radioactivity and can highlight any abnormal variation. In the case of an accident or incident leading to the release of radioactive substances, these measurement networks would play an essential role by providing data to inform the decisions to be taken by the authorities and to inform the population. In normal situations, they contribute to the evaluation of the impact of BNIs (see chapter 3). However, there is no overall monitoring system able to provide an exhaustive picture of the doses received by the population as a result of nuclear activities. Consequently, compliance with the population exposure limit (effective dose set at 1 mSv per year) cannot be controlled directly. However, for BNIs, there is detailed accounting of radioactive effluent discharges and radiological monitoring of the environment is implemented around the installations. On the basis of the data collected, the dosimetric SOURCES AND ROUTES OF EXPOSURE TO IONISING RADIATION Inhalation External irradiation Skin contamination External radiation Internal contamination by inhalation of radioactive substances Skin contamination Ingestion External irradiation Skin contamination and involuntary ingestion External radiation Internal contamination through ingestion of contaminated foodstuffs Skin contamination and involuntary ingestion 108 ASN Report on the state of nuclear safety and radiation protection in France in 2021 01 – NUCLEAR ACTIVITIES: IONISING RADIATION AND HEALTH AND ENVIRONMENTAL RISKS
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