ASN Report 2018
authorities and by notifying the population. In a normal situation, 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 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 reference groups chosen, from a few microsieverts to several tens of microsieverts per year. There are no known estimates for nuclear activities other than BNIs owing to the methodological difficulties involved in identifying the impact of the facilities and in particular the impact of discharges containing small quantities of artificial radionuclides resulting from the use of unsealed radioactive sources in research or biology laboratories, or in nuclear medicine units. To give an example, the impact of hospital discharges could lead to doses of a several tens of microsieverts per year for the most exposed persons, particularly for certain jobs in sewage networks and wastewater treatment plants (IRSN studies 2005 and 2015). Legacy situations, such as atmospheric nuclear tests and the Chernobyl accident (Ukraine), can make a marginal contribution to population exposure. Thus the average individual effective dose currently being received in metropolitan France as a result of fall-out from the Chernobyl accident is estimated at between 0.01 mSv and 0.03 mSv/year (IRSN 2001). That due to the fall-out from atmospheric testing was estimated in 1980 at about 0.02 mSv. Given a decay factor of about 2 in 10 years, current doses are estimated at well below 0.01 mSv per year (IRSN, 2015). With regard to the fall-out in France from the Fukushima Daiichi accident (Japan), the results published for France by IRSN in 2011 show the presence of radioactive iodine at very low levels, resulting in very much lower doses for the populations than those estimated for the Chernobyl accident, and having negligible impact. 3.2.2 – Exposure of the population to Naturally Occurring Radioactive Materials (NORM) • Exposure due to natural radioactivity in drinking water The results of the monitoring of the radiological quality of the tap water distributed to consumers carried out by the regional health agencies between 2008 and 2009 (DGS/ASN/IRSN report published in 2011) showed that 99.83% of the population receives tap water whose quality complies at all times with the total indicative dose of 0.1mSv/year set by the regulations. This basically satisfactory assessment also applies to the radiological quality of the bottled water produced in France (DGS/ASN/IRSN report published in 2013). As from 2019, measurement of the radon content of tap water and bottled water will be compulsory. To assist the introduction of this new provision, an instruction was drawn up in consultation with ASN and issued in 2018 to the Regional Health Agencies by the General Directorate for Health (ASN opinion 2018-AV-0302 of 6 March 2018 on the radon management procedures in the sanitary control of water intended for human consumption). • Exposure due to radon Since 1999, it is compulsory to take periodic radon measurements in places open to the public, especially in educational institutions and healthcare and social institutions, due to the risk of lung cancer attributable to prolonged exposure to radon. Since August 2008, this compulsory monitoring has been extended to workplaces located in the priority geographical areas. On the basis of the results communicated by the ASN-accredited organisations for the 2017/2018 campaign, more than 95% of the screenings were carried out in educational institutions and healthcare and medical-social institutions (48% and 46% of screenings respectively). The radon activity concentration is lower than the action threshold of 400 Bq/m 3 in 79% of educational institutions and 87% of the healthcare and medical- social institutions screened. For the institutions in which the radon activity concentration exceeds 400 Bq/m 3 , simple remediation measures or works must be carried out to lower the radon activity concentration to below this threshold. This threshold was reduced in June 2018 to 300 Bq/m 3 . Nearly 50% of the post-work inspections carried out by the ASN-accredited organizations confirmed that the radon activity concentration had been brought below the 400 Bq/m 3 threshold. The results of the inspections in places open to the public are not appropriate for precisely assessing the doses linked to exposure of the general public due to the fact that exposure in the home accounts for the largest part of the doses received during one’s lifetime. Informing and heightening the awareness of the public and the main actors concerned by the radon risk (regional authorities, employers, etc.) are therefore essential and are now entered as a top strategic priority in the 3rd National Plan for Radon Risk Management. This national plan for the 2016-2019 period is coordinated by ASN. It was published in January 2017. In this new plan, the strategy of informing and raising awareness is based on the new legislative measures adopted in 2016. Prominent among these is the obligation to inform real estate buyers and tenants of the health risks associated with radon in the home. Deployment of the 3rd National Plan for Radon Risk Management 2016-2019, which accompanies the updating of the regulations in this area (see the “References” heading on asn.fr ) and the publication in June 2018 of the new mapping of localities considered as priorities with regard to the radon risk, should allow an increase in communication towards the public in order to heighten awareness of this risk. In consultation with the public administrations concerned Regional Health Agencies (ARS), Regional Directorate for the Environment, Planning and Housing (Dreal), Regional Directorate for Enterprises, Competition, Consumption, Labour and Employment (Direccte)), the regional divisions of ASN are committed to taking part in the information actions and performing inspections, particularly in buildings open to the public. ASN report on the state of nuclear safety and radiation protection in France in 2018 101 01 – NUCLEAR ACTIVITIES: IONISING RADIATION AND HEALTH AND ENVIRONMENTAL RISKS 01
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