This publication describes the work undertaken by Working Group 6: Biosphere Modelling for Long Term Safety Assessments of Waste Disposal Facilities of the IAEA’s Modelling and Data for Radiological Impact Assessments (MODARIA II) programme (2016–2019). The objective of this publication is to provide updated guidance for addressing the biosphere in undertaking post-closure safety assessments for solid radioactive waste disposal, building on the original BIOMASS methodology published in 2003. The intended audience includes regulators and organizations responsible for assessing and reviewing safety assessments and assessors and modellers involved in a range of radiological studies within the nuclear industry.
In 2004, the Indian Ocean Tsunami damaged several nuclear installations in India. In 2011, the Great East Japan Earthquake and Tsunami caused the Fukushima Daiichi nuclear accident. These events have focussed international attention on the importance of protecting nuclear facilities against such natural hazards. This IAEA Safety Report presents detailed methodologies and recent case studies for the design and safety assessment of coastal nuclear installations, especially with a view to providing defence in depth. It complements IAEA Safety Standards Series No. SSG-18, Meteorological and Hydrological Hazards in Site Evaluation for Nuclear Installations, published in 2011, by introducing the latest knowledge of tsunami and seiche hazards based on real major events and related data, and their effects on nuclear sites. This publication is designed to be of use for all IAEA Member States that have nuclear installations near their shorelines.
Planning, Management and Conduct of Regulatory Safety Review and Assessment for Nuclear Power Plants
Establishing a well-defined, well-organized and clear regulatory review and assessment process at each licensing step is key to achieving the highest level of safety throughout the lifetime of a nuclear power plant. Reflecting a project management approach adopted in many States, this publication provides practical guidance for the planning, management and conduct of the review and assessment by regulatory bodies of applications for authorization. It is intended for the managers and staff of regulatory bodies of States, particularly those embarking on a nuclear power programme, who are involved in the regulatory review and assessment process.
Elaborating upon the requirements on periodic safety reviews that are established in IAEA Safety Standards Series No. SSR-4, Safety of Nuclear Fuel Cycle Facilities, this publication aims to provide practical information on conducting the periodic safety review for a nuclear fuel cycle facility by the operating organization, and on the regulatory review and assessment of the periodic safety review. The publication covers the planning and preparation for periodic safety review, use of a graded approach, review of safety factors, global assessment of the safety of the facility and development of an implementation plan to address the findings of the periodic safety review.
This publication describes the updated version of the method for the assessment of comprehensiveness of defence in depth and demonstrates the overall improvement in assessment results when using it. For assessment of comprehensiveness, five levels of defence in depth are considered. To ensure that safety objectives are met at each level of defence in depth, the integrity of relevant fission product barriers is maintained by the safety functions. A set of challenges to the performance of safety functions and the mechanisms leading to the challenges are specified by the method. Finally, a comprehensive list of safety provisions, which contribute to preventing these mechanisms from occurring, is specified. These provisions encompass the inherent safety features, equipment, procedures, personnel availability, personnel training and safety culture aspects. The challenges, mechanisms and provisions for all levels of defence in depth are presented in the assessment method in the form of objective trees.
The objective of this Safety Report is to provide information on the implementation of IAEA Safety Standards Series SSG-48, to support the ageing management and preparation for the safe, long-term operation of a nuclear power plant. It addresses ageing management of active and passive structures and components for water moderated reactors that can have an effect, directly or indirectly, on the safe operation of the plant and that are susceptible to ageing. This publication is intended for ageing management and long-term operation specialists as well as nuclear power plant managers, regulatory bodies and technical support organizations.
In recent years, significant experience of the effects of high wind and flooding on nuclear installations has been gained worldwide. These phenomena may simultaneously affect all the structures, systems and components important to safety at a nuclear installation site. By detailing the methodologies and providing case studies for the evaluation of meteorological and hydrological hazards, this publication supports IAEA Safety Standards Series No. SSG-18, Meteorological and Hydrological Hazards in Site Evaluation for Nuclear Installations. In the first part of the publication, wind hazards relating to tropical cyclones, tornadoes, extratropical storms, thunderstorms and wind-borne debris are discussed. The second part covers external flooding hazards (excluding tsunamis) relating to wind induced coastal flooding, wind generated waves on rivers, extreme precipitation and runoff events and the sudden release of impounded water.
In response to an increase in global activities related to non-water-cooled reactors and small modular reactors, this new Safety Report documenting areas of novelty of these technologies when compared to the current fleet of reactors has been developed. The impact of these areas of novelty on the applicability and completeness of the IAEA safety standards is assessed in the publication. Gaps and areas for additional consideration are identified. The review undertaken to develop this report encompassed the safety standards related to the lifetime of these reactor technologies. The publication also considers the interface between safety, security, and safeguards in the design of these technologies.
This IAEA Safety Report describes neutron monitoring procedures and equipment that may be used for radiation protection in nuclear power production, medical and industrial applications, research institutions and civil air service. It provides guidance on measuring operational quantities of neutron radiation and practical advice for safely carrying out neutron radiation protection dosimetry, including methods for establishing traceability of those measurements to national standards. This publication is intended for designers and manufacturers of radiation monitors and personal dosimeters and radiation protection professionals who develop radiation protection standards or neutron monitoring programmes.
This Safety Report explains how the concepts of attribution of health effects and inference of risks can be taken into account in the application of IAEA safety standards, so as to implement them more effectively. In particular, this publication demonstrates explicitly what the relevant provisions of the safety standards are for high and moderate levels of exposure where health effects might be able to be attributed to the exposure, and for low and very low levels of exposure where risks can only be inferred. This Safety Report also aims to support more effective communication by clarifying the proper use of certain concepts detailed in the safety standards and plain language explanations of the concepts of attribution of effects and inference of risk are provided.
A periodic safety review is considered an effective way to obtain an overview of nuclear power plant safety. It is also used to determine reasonable and practicable modifications to maintain a high level of safety during continued operation, and to justify operation of a nuclear power plant beyond the original time frame. The review considers life limiting processes and features of structures, systems and components important to safety, and whether there are any foreseeable circumstances that could endanger the safe operation of the nuclear power plant. This publication addresses the scope of assessment, methods and applicable criteria within the periodic safety review and long term operation programmes framework, to support decision making for long term operation of nuclear power plants.
This Safety Report provides guidance, targeted towards States newly embarking upon a nuclear power plant programme, on the licensing process and associated procedures needed during for the construction, commissioning and operation stages of a nuclear power plant, so that the applicant complies with national regulations in line with the internationally recognized safety principles and requirements throughout these stages. The publication elaborates on the generic guidance provided in IAEA Safety Standards Series No. SSG-12, Licensing Process for Nuclear Installations, and gives supplementary practical guidance for nuclear power plants.