ASN Report 2018

1.1.3  –  Precautionary principle The precautionary principle, defined in Article 5 of the Environment Charter, states that: “the absence of certainty, in the light of current scientific and technical knowledge, must not delay the adoption of effective and proportionate measures to prevent a risk of serious and irreversible damage to the environment” . Application of this principle results, for example, in the adoption of a linear, no-threshold dose-effect relationship where the biological effects of exposure to low doses of ionising radiation are concerned. This point is clarified in chapter 1 of this report. 1.1.4  –  Public participation principle This principle allows public participation in the taking of decisions by public authorities. In line with the Aarhus Convention, it is defined in Article 7 of the Environment Charter as follows: “Within the conditions and limits defined by law, all individuals are entitled to access environmental information in the possession of the public authorities and to participate in the taking of public decisions affecting the environment” .  In the nuclear field, this principle notably leads to the organisation of national public debates, which are mandatory prior to the construction of a nuclear power plant for example, or now before certain plans and programmes subject to strategic environmental assessments, such as the National Radioactive Material and Waste Management Plan (PNGMDR). One should also mention the public inquiries, notably during examination of the files concerning the creation or decommissioning of nuclear installations, consultation of the public on draft resolutions with an impact on the environment, or the submission by a Basic Nuclear Installation (BNI) licensee of its file concerning a modification to its installation liable to lead to a significant increase in water intake or discharges into the environment of the installation. 1.1.5  –  Justification principle The justification principle, defined in Article L. 1333-2 of the Public Health Code, states that: “A nuclear activity or an intervention may only be undertaken or carried out if its individual or collective benefits, more specifically its health, social, economic or scientific benefits so justify, given the risks inherent in the human exposure to ionising radiation that it is likely to entail”. Assessment of the expected benefit of a nuclear activity and the corresponding drawbacks may lead to prohibition of an activity for which the benefit would not seem to outweigh the health risk. For existing activities, justification may be reassessed if the state of know-how and technology so warrants. 1.1.6  –  Optimisation principle The optimisation principle, defined by Article L. 1333-2 of the Public Health Code, states that: “The level of exposure of individuals to ionising radiation […], the probability of occurrence of this exposure and the number of persons exposed must be kept as low as is reasonably achievable, given the current state of technical knowledge, economic and social factors and, as necessary, the medical goal in question” .  This principle, referred to as the ALARA (As Low As Reasonably Achievable) principle, leads for example to reducing the quantities of radionuclides present in the radioactive effluents from nuclear installations allowed in the discharge licenses, to requiring monitoring of exposure in the working environment in order to reduce it to the strict minimum and to ensuring that medical exposure as a result of diagnostic procedures remains close to the pre-determined reference levels. 1.1.7  –  Limitation principle The limitation principle, defined in Article L. 1333-2 of the Public Health Code, states that: “[…] Exposure of an individual to ionising radiation […] may not increase the sum of the doses received beyond the limits set by regulations, except when the individual is exposed for medical purposes or for the purposes of research as mentioned in 1° of Article L.1121-1” . The exposure of the general public or of workers as a result of nuclear activities is subject to strict limits. These limits include significant safety margins to prevent deterministic effects from appearing, as well as aiming to reduce the appearance of probabilistic effects in the long term to the lowest level possible. Responsibility of licensees and responsibility of ASN The Nuclear Safety Authority (ASN) The leading licensees (EDF, CEA, Andra, Areva) and the other licensees or users of ionising radiation Defines general safety and radiation protection objectives Propose procedures for achieving the objectives Implement the approved provisions Reviews whether these procedures are capable of achieving these objectives Supervises the implementation of these provisions ASN report on the state of nuclear safety and radiation protection in France in 2018  109 02 – THE PRINCIPLES OF NUCLEAR SAFETY AND RADIATION PROTECTION AND THE REGULATION AND OVERSIGHT STAKEHOLDERS 02