ASN Report 2020

The criteria for notifying the public authorities of events considered to be “significant” take account of the following: ∙ the actual or potential consequences for workers, the public, patients or the environment, of events that could occur and affect nuclear safety or radiation protection; ∙ the main technical, human or organisational causes that led to the occurrence of such an event. This notification process is part of the continuous safety and radiation protection improvement approach. It requires the active participation of all players (users of ionising radiation, carriers, etc.) in the detection and analysis of deviations. It enables the authorities: ∙ to ensure that the licensee has suitably analysed the event and taken appropriate measures to remedy the situation and prevent it from happening again; ∙ to ensure that other parties responsible for similar activities benefit from experience feedback about the event. The purpose of this system is not to identify or penalise any individual person or party. Moreover, the number and rating on the International Nuclear and Radiological Event Scale (INES scale) of the significant events which have occurred in a nuclear facility are not on their own indicators of the facility’s level of safety. On the one hand, a given rating level is an over-simplification and is unable to reflect the complexity of an event and, on the other, the number of events listed depends on the level of notification compliance. The trend in the number of events does not therefore reflect any real trend in safety levels. 3.3.2 Implementation of the approach Event notification The licensee of a BNI or the person responsible for the transport of radioactive substances is obliged to notify ASN and, as applicable, the administrative authority, without delay, of any accidents or incidents that occur on account of the operation of that installation or the transport activity and which could significantly prejudice the interests mentioned in Article L. 593-1 of the Environment Code. Similarly, the party responsible for a nuclear activity must notify any event which could lead to accidental or unintentional exposure of persons to ionising radiation and liable to significantly prejudice the protected interests. According to the provisions of the Labour Code, employers are obliged to report significant events affecting their workers. When the head of a company carrying out a nuclear activity calls in an external contractor or non-salaried worker, the significant events affecting salaried or non-salaried workers are notified in accordance with the prevention plans and the agreements concluded pursuant to the provisions of Article R. 4451-35 of the Labour Code. The notifying party assesses the urgency of notification in the light of the confirmed or potential seriousness of the event and the speed of reaction needed to avoid an aggravation of the situation or to mitigate the consequences of the event. The notification time of two working days, mentioned in the ASN notification guides, does not apply when the consequences of the event require intervention by the public authorities. When a given event potentially concerns several facilities, it is referred to as a “generic” event. The most common example is a fault in an equipment item installed on several nuclear reactors (see chapter 10). In this case, ASN analyses the event as a single event, with the response being essentially common to all the facilities affected. This process follows the IAEA recommendations, which specify that a single notification may be appropriate in the case of an event affecting defence in depth and concerning several similar facilities. ASN analysis of the notification ASN analyses the initial notification to check the implementation of immediate corrective measures, to decide whether to conduct an on-site inspection to analyse the event in depth, and to prepare for informing the public if necessary. Within two months of the notification, it is followed by a report indicating the conclusions the licensee has drawn from analysis of the event and the steps it intends to take to improve safety or radiation protection and prevent the event from happening again. This information is taken into account by ASN and its technical support organisation, the IRSN, in the drafting of the inspection programme and when performing the BNI periodic safety reviews. ASN ensures that the licensee has analysed the event pertinently, has taken appropriate steps to remedy the situation and prevent it from recurring, and has circulated the operating experience feedback. The ASN review focuses on compliance with the applicable rules for detecting and notifying significant events, the immediate technical, organisational or human measures taken by the licensee to maintain or bring the installation into a safe condition, and the pertinence of the submitted analysis. ASN and the IRSN also carry out a more wide-ranging examin­ ation of the operating feedback from the events. The significant event reports and the periodic reviews sent by the licensees, as well as the assessment by ASN and the IRSN, constitute the basis of operating experience feedback. The examination of operating experience feedback may lead to ASN requests for improvements to the condition of the facilities and the organisation adopted by the licensee, but also to changes to the regulations. OEF comprises the events which occur in France and abroad in nuclear facilities or in those presenting non-radiological hazards, if it is pertinent to take them into account in order to reinforce nuclear safety or radiation protection. 3.3.3 Technical inquiries held in the event of an incident or accident concerning a nuclear activity ASN has the authority to carry out an immediate technical inquiry in the event of an incident or accident in a nuclear activity. This inquiry consists in collecting and analysing all useful information, without prejudice to any judicial inquiry, in order to determine the circumstances and the identified or possible causes of the event, and draw up the appropriate recommendations if necessary. Articles L. 592-35 et seq. of the Environment Code give ASN powers to set up a board of inquiry, determine its composition (ASN staff and people from outside ASN), define the subject and scope of the investigations and gain access to all necessary elements in the event of a judicial inquiry. Decree 2007-1572 of 6 November 2007 on technical inquiries into accidents or incidents concerning a nuclear activity specifies the procedure to be followed. It is based on practices defined for the other boards of inquiry and takes account of aspects specific to ASN, notably its independence, its own roles, its ability to impose binding requirements or sanctions. ASN Report on the state of nuclear safety and radiation protection in France in 2020 157 03 – REGULATION OF NUCLEAR ACTIVITIES AND EXPOSURE TO IONISING RADIATION 03