ASN Report 2020

workers in the industries concerned remained 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. With regard to exposure to radon of geological origin, the results from monitoring the exposure of workers to radon have not yet been exhaustively recorded in Siseri. Consequently, not all the companies whose premises have a radon activity concentration in the air that makes individual monitoring necessary are included in the IRSN 2019 report published in October 2020. 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, the IRSN calculates individual doses 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 31st December 2019, SievertPN had transmitted to Siseri all the flight crew doses for 15 airlines having subscribed to the system, giving a total of 24,429 flight crew members monitored by this system. In 2019, 16.8% of the individual annual doses were below 1 mSv and 83% of the individual annual doses were between 1 mSv and 5 mSv. The maximum individual annual dose was 6.2 mSv. 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 the 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 back the decisions to be taken by the authorities and by notifying 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/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 impact of these discharges on the populations in the immediate vicinity of the installations is then calculated using models simulating transfers to the environment. The dosimetric impacts vary, according to the type of installation and the lifestyles of the chosen reference groups, from a few microsieverts to several tens of microsieverts per year. An estimation of the doses from BNIs is presented in Table 4 which shows, for each site and per year, the estimated effective doses received by the most exposed reference population groups. Results of dosimetry monitoring of worker external exposure to ionising radiation (exposure to natural radioactivity included) in 2019 (Source: IRSN 2019 report, October 2020 – “ Worker radiation protection: occupational exposure to ionising radiation in France ”) ཛྷ Total population monitored: 395,040 workers ཛྷ Monitored population for whom the annual effective dose remained below the detection threshold: 301,493 workers, or more than 76% ཛྷ Monitored population for whom the annual effective dose remained between the detection threshold and 1 mSv: 59,468 workers, or more than 15% ཛྷ Monitored population for whom the annual effective dose remained between 1 mSv and 20 mSv: 34,074 workers, or more than 8.6% ཛྷ Monitored population for whom the annual effective dose exceeded 20 mSv: 5 workers ཛྷ Monitored population for whom the equivalent dose to the extremities exceeded 500 mSv: 1 worker ཛྷ Collective dose (sum of the individual effective annual doses): 112.3 man-Sv ཛྷ Average annual individual effective dose in the population which recorded a dose higher than the detection threshold: 1.2 mSv Results of internal exposure monitoring in 2019 (natural radioactivity excluded) ཛྷ Number of routine examinations carried out: 228,808 (of which 0.5% were considered positive) ཛྷ Population for which a dose estimation was made: 217 workers ཛྷ Number of special monitoring examinations or verifications performed: 10,053 (of which 15% were above the detection threshold) ཛྷ Population having recorded a committed effective dose exceeding 1 mSv: 9 workers Results of monitoring of internal exposure to natural radionuclides from the uranium and thorium decay chains in 2019 ཛྷ Internal exposure: • collective dose for 363 workers: 126.5 man-mSv • Average annual individual effective dose in the population which recorded a dose higher than the detection threshold: 0.52 mSv ASN Report on the state of nuclear safety and radiation protection in France in 2020 111 01 – NUCLEAR ACTIVITIES: IONISING RADIATION AND HEALTH AND ENVIRONMENTAL RISKS 01