NEA Mandates and Structures

Working Group on Reactor Oversight (WGRO)

Mandate (Document reference):

• Participant Status of India in the CNRA and its subsidiary bodies: 2018 Update of the NEA Participation Plan [NEA/NE(2018)8] and official letter received from India on 15 October 2018 confirming its acceptance of Participant Status in the CNRA and its subsidiary bodies
• Summary Record of the 47th CNRA meeting held on 2-3 June 2022 [NEA/SEN/NRA(2022)1]
• Mandate of the Working Group on Reactor Oversight (WGRO) [NEA/SEN/NRA(2022)6]
• Summary Record of the 53^rd CNRA meeting held on 5-6 June 2025 [NEA/SEN/NRA(2025)1, forthcomiing]
• Mandate of the Working Group on Reactor Oversight (WGRO) [NEA/SEN/NRA/WGRO(2025)1/FINAL]

Mandate (Document extract):

Extract of document NEA/SEN/NRA/WGRO(2025)1/FINAL

Background

The oversight of nuclear power plants (NPPs) is an important function for a nuclear safety regulator as it provides a valuable source of information for independently verifying the safety and reliability of NPPs. In this context, “oversight” refers to the strategic process by which regulators collect information about NPP performance; analyse the safety significance of that information; and respond accordingly.  The types of information available to the regulator will vary from country-to-country, but typical examples include inspection results, operating experience, and quantitative indicators of plant performance (e.g., number of un-planned SCRAMs in a given period of time).  It is the function of the regulator to evaluate this information in a holistic manner so as to ensure informed regulatory decisions.

Amongst all aspects of reactor oversight, inspection shall receive special attention due to its importance to regulators and because experience has shown that the exchange of commendable practices is particularly valuable in this area.  In this context, “inspection” means an examination, observation, measurement or test to assess structures, systems, components, materials, operational activities, processes, procedures, and personnel and organisational competence, while a “commendable practice” is a practice that, if adopted by a regulatory body, could improve effectiveness and/or efficiency. Commendable practices are not international standards or guidelines and their adoption is at the discretion of each regulatory body. 

An additional important area of focus is the evaluation of operating experience to identify global trends, lessons learned and to develop specific recommendations for regulators in the short to medium term.  Examples of these recommendations may include proposals for re-assessment of safety, additional research, new or revised regulatory inspection practices, improvements in managing operations and other actions to maintain and improve safety in the long term.

Mandate

The mandate of the Working Group on Reactor Oversight (WGRO) is to provide a mechanism for nuclear safety regulators and Technical Support Organizations (TSOs) to share their knowledge and experience on both the human and technical aspects of reactor oversight. 

The WGRO seeks to facilitate an active and timely exchange of commendable practices, as well as lessons learned to help regulators perform their function more effectively and efficiently. 

The WGRO and any subsidiary bodies it creates should focus on reactor oversight and analyse operating experience in order to promote consistency of regulatory practices.

Scope

The WGRO will focus on identifying and sharing relevant good practices in reactor oversight that provide the necessary assurances of day-to-day safe operation on nuclear power plants, with special attention to inspection.

The WGRO will also serve as a forum to share information on safety-relevant events and assessment of those events by the regulatory body, with the aim to evaluate operating experience to identify global trends, lessons learned and to develop specific recommendations for regulators in the short to medium term.

The primary focus of the group will be on operating power reactors, but it will also include experiences from other phases of the reactor lifecycle as well. When a knowledge transfer to oversight of nuclear power reactors is directly applicable, the group will also consider other nuclear facilities or industries.

Objectives

The WGRO will collect and analyse information so that it can share:

• methods, practices, and technologies to ensure that oversight is conducted in a manner that promotes new and established good practices;
• methods to integrate information collected from all oversight activities in order to make decisions in a technically-sound manner;
• best practices and methods to help regulatory bodies focus on areas of great safety significance; 
• information and experience related to inspection practices (e.g. planning, conducting, documenting) and programmes;
• methods to evaluate and improve the effectiveness and efficiency of inspections including the use of innovative technologies;
• methods to assess and/or rate the safety significance of inspection findings and results;
• information from important-to-safety operational events and inspection findings from all phases of the nuclear power lifecycle e.g. from the International Reporting System for Operating Experience (IRS) and other databases;
• improved techniques and methods to collect and evaluate national and international operational experience and use this information to provide regulators with recommendations such as re-assessment of safety, additional research, new or revised regulatory inspection practices, improvements in managing operations, and other actions to maintain and improve safety in the long term.

Working methods

The WGRO will:

• be led by a Bureau (consisting of a Chair and at least one Vice Chair) designated and acting according to the OECD guidelines;
• constitute a forum of international experts from regulatory bodies and technical support organisations which will meet in person at least once per year;
• charter and oversee the work of targeted, limited term subsidiary bodies (e.g., green booklet task groups, information exchange forums, expert groups) to conduct analyses and develop reports on subjects of particular interest. Operating experience plays a fundamental role in the identification of improvements to nuclear safety. As such, WGRO shall utilise the Expert Group on Operating Experience for planned and targeted activities in direct support to its mandate;
• organise, on a regular basis, workshops, on-site activities (such as observed inspections) ;
• organise specific training activities and conferences on demand / as appropriate, including non-member experts in these activities upon WGRO’s prior agreement;
• provide a forum for subject matter experts in member countries to directly observe the planning and conduct of oversight activities (e.g., inspection) in other member countries; and
• report to the CNRA and assist the Committee with its work. The WGRO programme of work will be approved by the CNRA.

Membership

The WGRO is comprised of senior international experts from regulatory bodies and TSOs.

Interactions

The WGRO will closely co-ordinate with and exchange input with other NEA bodies, especially other CNRA working groups. It will work closely with the Committee on the Safety of Nuclear Installations (CSNI) to deeply investigate specific technical or organizational issues that are identified during its analysis.

The WGRO will also co-ordinate as appropriate with other international organisations (e.g. IAEA, the European Commission), international non-governmental organisations (e.g. WANO), and the International Reporting System for Operating Experience (IRS).

Deliverables

The WGRO will produce guidance documents for nuclear safety regulators and other stakeholders interested in commercial nuclear power.  Examples include, but are not limited to, green booklets, proceedings of seminars and workshops, collections of commendable practices implemented by regulatory bodies, case studies, and summaries of operating experience.