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One of the many lessons learnt about nuclear safety over the years has been that human aspects of nuclear safety are as important as any technical issue that may arise. The international nuclear community regularly works together to identify, discuss and address technical issues, but examining how behaviour affects safety from country to country remains less common. Yet practical experience has shown that there are important differences across borders and even within borders in how people work together and communicate.
The Country-Specific Safety Culture Forum was created to gain a better understanding of how the national context affects safety culture in a given country and how operators and regulators perceive these effects in their day-to-day activities. The ultimate goal is to ensure safe nuclear operations. The third NEA safety culture forum – a collaborative effort between the Nuclear Energy Agency (NEA), the World Association of Nuclear Operators (WANO) and the Canadian Nuclear Safety Commission (CNSC) – was held in Canada in September 2022. This report outlines the process used to conduct the forum, reveals its findings and encourages the nuclear community to further reflect and take relevant action.
There is significant international interest in the effects of temperature on criticality safety evaluations. Improved access to nuclear data, notably thermal scattering data S(α,β) for hydrogen in ice, has made it possible to assess and deepen the understanding of the variation of criticality calculations associated with temperature.
Under the auspices of the Nuclear Energy Agency (NEA) Nuclear Science Committee (NSC) and of the Working Party on Nuclear Criticality Safety (WPNCS), Subgroup 3 was launched to study the impact of temperature through a wide range of codes, data libraries and methods. The group studied a pressurised water reactor (PWR) assembly in a thick water reflector at five different temperatures, ranging from ice to room temperature and up to reactor operation temperature. Ten organisations in eight countries participated, providing 34 sets of results.
With a view to launching the activity and obtaining results in a timely fashion, geometrical and material data from a previous WPNCS benchmark model were used in a new study to help examine the effect of temperature on criticality safety calculations.
The exercise was successful in bringing together a large number of institutions and employing a wide range of calculation codes and nuclear data libraries, thereby providing solid evidence for the conclusions drawn. The participants’ dedication made it possible to complete the exercise in two years, providing timely support to end users.
This report contains the benchmark study and results, and was endorsed at the WPNCS Subgroup 3 meeting in July 2020.
International co-operation is key to keep enhancing global nuclear safety. In this regard, the NEA Working Group on the Analysis and Management of Accidents (WGAMA) seeks to advance the scientific and technological knowledge base needed for the prevention, mitigation and management of potential accidents in nuclear power plants, and to encourage international convergence on safety issues in this area.
This report aims to facilitate communication between reactor safety stakeholders by summarising the main aspects of the WGAMA activities. It discusses the key safety topics related to the analysis and management of accidents and their context; the approach and methodologies to cope with reactor safety issues; recent reactor safety issues that have been dealt with; and potential future activities.
While there is a growing interest in the deployment of small modular reactors (SMRs) as a promising option to help mitigate climate change, further international efforts are needed to accelerate the development and safety demonstration of the innovative technologies that are being considered for many of these SMRs. This publication presents the actions taken by the NEA Committee on the Safety of Nuclear Installations (CSNI) and its expert group on SMRs to define the areas of future CSNI research and safety assessment work needed to support sound safety demonstrations for SMRs. The proposed activities address four areas: support for regulatory harmonisation, common safety issues of interest for different designs, experimental campaigns, and benchmarking for computer code validation and verification.
The disposal of long-lived radioactive waste in a deep geological repository (DGR) is a scientifically and technically credible solution that meets the need for long-term safety without reliance on active monitoring and management. Nevertheless, it is important to assess the potential risks that may be associated with such a nuclear installation and to ensure that an appropriate regime is in place to adequately compensate third parties in case they suffer nuclear damage caused by a DGR. Therefore, countries developing or intending to develop DGRs must take into account nuclear third party liability regime(s) as long as they apply to the disposal facilities. Those regimes establish a specific legal system that deviates from general tort law principles, including strict and exclusive liability of the operator of a nuclear installation, which will have to maintain a compulsory financial security to cover its liability.
Given the unusually long life cycles of such installations, this report discusses issues that concern future generations against the background of the currently applicable legal frameworks for the operation of nuclear installations, and existing technical knowledge, conscious that both will evolve. Nevertheless, it is important to identify and address potential issues regarding nuclear liability with the currently applicable legal frameworks and to set a clear framework for the applicable nuclear liability regime(s) during the different phases of operation of the DGR.
Knowledge of basic nuclear physics data is essential for the modelling and safe operation of all types of nuclear facilities. The de facto international standard format, Evaluated Nuclear Data File 6 (ENDF-6) format, was designed originally for 1960s era punch-card readers. The replacement of the system of codes built off this format has been recognised as an important initiative.
The ability to use increasingly high-fidelity nuclear physics, coupled to accurate uncertainties, is crucial for advanced simulations. This in turn requires more detailed and accurate data, then requiring improvements to the data storage standards, simultaneously enabling robust Quality Assurance and transfer of knowledge to the next generation.
In 2013, the NEA Working Party on International Nuclear Data Evaluation Co-operation (WPEC) launched a project to review the requirements for an international replacement for ENDF-6. The recommendations prompted the creation of a new Expert Group on a Generalised Nuclear Data Structure (GNDS) in 2016 that has used these requirements as the framework for a new format specification. Following rigorous international review, version 1.9 was unanimously approved as the first official published format in 2020. Since then, some 149 formal change requests were made to add new features and clarifications to the specifications, which were unanimously approved for publication in this release as version 2.0.
The radiation dose rate emitted by spent fuel assemblies is a crucial parameter within the framework of proliferation resistance, and its accurate determination is hence of paramount importance. Recent calculations have shown some discrepancies with historical results for pressurised water reactor spent fuel assemblies. To verify these discrepancies and help define a reference calculation, an international benchmark was carried out under the framework of the Nuclear Energy Agency (NEA) Expert Group on Advanced Fuel Cycle Scenarios (EGAFCS). The benchmark aimed to verify updated dose rate calculation procedures (new modelling approaches, new nuclear data, new versions of calculation codes) and share the benchmark results at the international level. The benchmark, including code-to-code verification and validation against experimental data, has shown and validated a methodology for the adequate estimation of the radiation dose rate from pressurised water reactor spent fuel assemblies (UOX and MOX) after certain periods of decay, confirming also the self-resistance of the simulated assemblies. This report outlines the exercise, its results and a series of recommendations for calculations.
This report aims to highlight the needs of integral experiments in the field of nuclear criticality safety, and to identify the available experimental facilities where such experiments could be performed.
In order to identify existing experimental needs, the NEA surveyed international nuclear criticality safety (NCS) practitioners and members of the Working Party on Nuclear Criticality Safety (WPNCS). Responses were received from eight organisations and five countries (Canada, the Czech Republic, France, Japan and the United States); additional responses were also sent by four organisations in two countries (Switzerland and the United Kingdom).
The survey results were examined by the WPNCS Subgroup on Experimental Needs for Criticality Safety Purposes (SG-5), which ranked the 25 identified needs in terms of priority as well as describing these needs in detail. A dedicated section of the report describes the existing proprietary experiments that might be used to meet some of the identified needs. Another section highlights some of the many facilities available to perform some of the prioritised criticality experiments.
Le Bulletin de droit nucléaire est une publication internationale unique en son genre destinée aux juristes et aux universitaires en droit nucléaire. Ses lecteurs bénéficient d’informations exhaustives qui font autorité sur les développements qui touchent ce droit. Publié gratuitement en ligne deux fois par an, en anglais et en français, il propose des articles thématiques rédigés par des experts juridiques renommés, rend compte du développement des législations à travers le monde et présente la jurisprudence et les accords bilatéraux et multilatéraux pertinents ainsi que les activités réglementaires des organisations internationales.
Ce numéro inclut notamment l’article et l’étude suivants : « Réflexions juridiques clés pour une réglementation axée sur les résultats » et « Procédure d’autorisation technologiquement neutre des réacteurs avancés : une évaluation du cadre de la NRC hier et aujourd’hui ».
Le Bulletin de droit nucléaire est une publication internationale unique en son genre destinée aux juristes et aux universitaires en droit nucléaire. Ses lecteurs bénéficient d’informations exhaustives qui font autorité sur les développements qui touchent ce droit. Publié gratuitement en ligne deux fois par an, en anglais et en français, il propose des articles thématiques rédigés par des experts juridiques renommés, rend compte du développement des législations à travers le monde et présente la jurisprudence et les accords bilatéraux et multilatéraux pertinents ainsi que les activités réglementaires des organisations internationales.
Ce numéro inclut notamment les articles suivants : « À la recherche de l’insaisissable conflit : (in)compatibilité des traités sur la non-prolifération et l’interdiction des armes nucléaires »; « De la confiance dans la gestion des déchets à l’entreposage prolongé : comment la NRC justifie l’autorisation des installations nucléaires en l’absence de centre de stockage « et « La nouvelle législation relative à la protection radiologique en Allemagne ».
All low-carbon solutions will be required to achieve the world's net zero targets. Nuclear energy has a role to play in meeting this need. A wave of innovation in small modular reactors (SMRs) is advancing quickly with the potential to help decarbonise hard-to-abate sectors. Progress is real and is positioned to accelerate pathways to net zero. SMRs could replace coal on-grid, fossil fuel cogeneration of heat and power for heavy industry, diesel at off-grid mines, as well as producing hydrogen and synthetic fuels.
Looking beyond technical feasibility, The NEA SMR Dashboard defines new criteria for assessing real progress in six additional dimensions of readiness: licensing, siting, financing, supply chain, engagement, and fuel. The first volume of the NEA SMR Dashboard assessed the progress of 21 SMRs. This second volume tracks the progress of an additional 21 SMRs around the world.
Uranium is the main raw material fuelling all nuclear fission reactors today. Countries around the world use it to reliably generate low-carbon electricity, process heat and hydrogen as part of their plans to reduce carbon emissions and increase energy security and supply. There is no nuclear fission power possible – of whatever kind – without uranium.
This 29th edition of the “Red Book”, a recognised world reference on uranium jointly prepared by the Nuclear Energy Agency (NEA) and the International Atomic Energy Agency (IAEA), provides analyses and information from 54 uranium producing and consuming countries. The present edition reviews world uranium market fundamentals and presents data on global uranium exploration, resources, production and reactor-related requirements. It offers updated information on established uranium production centres and mine development plans, as well as projections of nuclear generating capacity and reactor-related requirements through 2040.
Female scientists and engineers pioneered the nuclear and radiological fields, with leaders and innovators such as Marie Skłodowska-Curie and Lise Meitner, among many others, establishing the foundation of modern nuclear science and technology. Women continue to make vital contributions to the sector, but their visibility and overall numbers in the sector remain limited, especially in science, technology, engineering, and mathematics (STEM), and leadership roles. The lack of diversity in the sector represents a loss of potential innovation and growth and a critical threat to the viability of the field.
This report features the first publicly available international data on gender balance in the nuclear sector. The data was collected from over 8 000 women in the nuclear workforce in 32 countries, as well as human resources data from 96 nuclear organisations in 17 countries. Based on the findings, a comprehensive, evidence-driven policy framework is proposed with practical recommendations.
This report compiles and shares some of the lessons learnt from implementing post-Fukushima actions related to human and organisational factors (HOF), including at nuclear facility operating companies, technical support organisations, research institutions, and regulatory authorities. It summarises a two-phase information-gathering exercise, overseen by the NEA Working Group on Human and Organisational Factors, about the requirements and guidelines that countries and nuclear licensees have adopted since the accident. The report discusses the central role of human and organisational performance in mitigating extreme external events and the management of severe accidents. It addresses the importance of validating the ability to perform these actions, and the challenges associated with performing such validations with fidelity to the conditions likely to be present during such events. The report concludes by providing four key recommendations that seek to promote greater sharing of information and the identification of best practices.