2.2.2 Transport of radioactive substances When transporting radioactive substances, the main risks are those of internal or external exposure, of criticality, and risks of a chemical nature. Safe transport of radioactive substances relies on an approach called “Defence in Depth”: ∙ The robustness and the packaging is the first line of defence. The packaging plays an essential role and must withstand the conceivable transport conditions and the effects of accidents that could occur. ∙ The reliability of the transport operations constitutes the second line of defence. ∙ Finally, the third line of defence is the means of response implemented in the event of an incident or accident. 2.2.3 Small-scale nuclear activities Ionising radiation, whether emitted by radionuclides or generated by electrical equipment, is used in many areas, including medicine (radiology, radiotherapy, nuclear medicine and FluoroscopyGuided Interventional Practices – FGIPs), biology, research, industry, but also in veterinary applications, the sterilisation of numerous products, and the conservation of foodstuffs. The employer is required to take all necessary measures to protect workers against the hazards of ionising radiation. The facility licensee must also implement the provisions of the Public Health Code for the management of the ionising radiation sources in its possession (radioactive sources in particular) and, where applicable, manage the waste produced and limit discharges of liquid and gaseous effluents. In the case of use for medical purposes, patient protection issues are also taken into account. 2.2.4 Radioactive waste management Like all industrial activities, nuclear activities can generate waste, some of which is radioactive. The three fundamental principles on which strict radioactive waste management is based are the accountability of the waste producer, the traceability of the waste and informing the public. The technical management provisions to be implemented must be tailored to the hazard presented by the radioactive waste. This hazard can be assessed primarily through two parameters: the activity level, which contributes to the toxicity of the waste, and the half-life, the time after which the activity level is halved. Lastly, management of radioactive waste must be determined prior to the creation of any new activities or the modification of existing activities in order to: ∙ ensure the availability of processing channels for the various categories of waste likely to be produced, from the front-end phase (production of waste and its placing in packages) to the back-end phase (storage, transport and disposal); ∙ optimise the waste management routes. 2.2.5 Management of contaminated sites Management of sites contaminated by residual radioactivity resulting either from a past nuclear activity or an activity which generated deposits of natural radionuclides warrants specific radiation protection actions, in particular if rehabilitation is envisaged. Depending on the current or future uses of the site, decontamination objectives must be set. The removal of the waste produced during post-operation clean-out of the premises and removal of the contaminated soil must be managed from the site through to storage or disposal. The management of contaminated objects also follows these principles. 2.2.6 Activities using radioactive substances of natural origin Exposure to ionising radiation of natural origin, when increased due to human activities, justifies monitoring measures if it is likely to create a hazard for the exposed workers and, where applicable, the neighbouring population. Thus, certain activities included in the definition of “nuclear activities” can use materials containing naturally occurring radioactive materials at concentration levels that could significantly increase the exposure of workers to ionising radiation and, to a lesser extent, the exposure of populations living near the places in which these activities are carried out. The natural families of uranium and thorium are the main radionuclides found in these activities, which include: ∙ the production of oil and gas, geothermal energy, titanium dioxide, phosphate fertilizers and cement; ∙ the extraction of rare earths and granites; ∙ the casting of tin, lead and copper. The radiation protection measures to take in this area target not only the workers (risk of external irradiation and internal contamination, radon) but also the general public, for example in the case of effluent discharges into the environment or the production of residues that could be reused, in construction materials for example. Since 2018, these activities are subject to the system of Installations Classified for Protection of the Environment (ICPEs). 3 Monitoring of exposure to ionising radiation Given the difficulty in attributing a cancer solely to the ionising radiation risk factor, “risk monitoring” to prevent cancers in the population is performed by measuring ambient radioactivity indicators (measurement of dose rates for example), internal contamination or, failing this, by measuring values (activities in radioactive effluent discharges) which can then be used – by modelling and calculation – to estimate the doses received by the exposed populations. The entire population of France is exposed to ionising radiation of natural or anthropogenic origin, but to different extents across the country. The average exposure of the French population is estimated at 6.5 mSv per person per year, but this exposure is subject to wide individual variability (factor of 1 to 20), particularly depending on the place of residence (radon potential of the municipality, level of terrestrial radiation), the number of radiological examinations the person undergoes, consumption 106 ASN Report on the state of nuclear safety and radiation protection in France in 2023 • 01 • Nuclear activities: ionising radiation and health and environmental risks
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