Committee on Nuclear Regulatory Activities (CNRA)
    Working Group on the Regulation of New Reactors (WGRNR)

    Multinational Design Evaluation Programme (MDEP)

    Workshop on Regulatory Oversight of the Commissioning Phase for New Reactors

    Hilton Gyeongju
    Gyeongju City, Korea
    14-16 March 2016

    Organised in collaboration with KINS

    Organisation and host

    The Nuclear Energy Agency (NEA) Working Group on the Regulation of New Reactors (WGRNR) held a joint workshop with Multinational Design Evaluation Programme (MDEP) in collaboration with the Korea Institute of Nuclear Safety (KINS). The workshop was held from 14-15 March 2016, in Gyeongju City, Korea. A half-day technical tour was organised on 16 March 2016 to visit the construction site at Shin-Kori units 3 and 4.


    The Committee on Nuclear Regulatory Activities (CNRA) Working Group on the Regulation of New Reactors (WGRNR) constitutes a forum of experts on the licensing of new and advanced commercial nuclear power reactors seeking to facilitate a co-operative approach to identifying key new regulatory issues, and to promote a common resolution.

    The main purposes of the WGRNR and its products are to:

    • improve regulatory reviews by comparing practices in member countries;
    • improve the licensing process of new reactors by learning from best practices in member countries;
    • ensure that construction inspection issues and construction experience are shared;
    • promote co-operation among member countries to improve safety and enhance the effectiveness and efficiency of the regulatory process.

    The WGRNR is the main point of contact between the Multinational Design Evaluation Programme (MDEP) and the CNRA and aims to co-ordinate its work with that of the MDEP in such a way that it utilises its outputs and does not duplicate its efforts. It also extends the results of MDEP to other CNRA members.

    At its 31st meeting, the CNRA recognised the generic aspects of regulatory oversight of the commissioning phase for new reactors as a new task for the WGRNR. Accordingly, MDEP design-specific working groups (DSWGs) are addressing commissioning activities specific to a design and WGRNR is covering generic commissioning activities. This was formally agreed on by the CNRA and MDEP chairs.

    In this context, WGRNR organised a joint workshop with the MDEP on the regulatory oversight of the commissioning phase for new reactors in March 2016.


    The workshop was an opportunity to bring together experts from nuclear regulatory organisations (NROs) on commissioning activities. Its main purpose was to stimulate co-operation and share commendable practices and recent experience from international regulatory approaches for the commissioning of new reactors. The workshop focused on generic aspects of the topics, including regulatory priorities and practices, oversight and regulation of commissioning tests and activities, and commissioning issues which are not design-specific. Information obtained as a result of this workshop should have helped participants to understand key regulatory issues during the commissioning phases of new reactors, and to promote sharing of methods to address them. The outputs of the workshop will be recorded in the form of a report proposing commendable practices to help NROs develop their commissioning oversight arrangements, and plan and perform their commissioning oversight activities. The workshop focused on a limited number of major issues which were identified as being challenging or safety-significant during commissioning.

    Workshop topics and format

    The workshop lasted two days and was partially split into three parallel group sessions (see Attachment 1). The morning session of the first day was dedicated to an introductory presentation from the WGRNR followed by a presentation on the commissioning activities of each MDEP DSWGs. The group sessions took place in parallel and were devoted to discussions among participants on the topics outlined in the table below. For each topic, some questions were detailed in Attachment 2. Short position papers were sought from participants, and a discussion on the bases of the different countries' regulatory approaches and lessons learnt was facilitated. The group sessions were moderated by a chair from WGRNR or MDEP, and assisted by a rapporteur from MDEP or WGRNR. The rapporteur took notes of the topical discussions and prepared a summary of each topic. At the closure session, the three rapporteurs presented a summary on each topic of their group, and conclusions and recommendations were drafted. All participants were expected to take part in the discussion in the group sessions and in the formulation of conclusions in the final session.

    Commissioning management Commissioning oversight Organisational issues
    1.A. Application of commissioning experience and operating experience 2.A. Regulatory hold points and witness points 3.A. Inspection for licensee organisational readiness

    1.B. Selection of tests and acceptance of tests results


    2.B. Bases for inspection 3.B. Oversight of safety culture during commissioning stage
    2.C. Tests sampling criteria 3.C. Oversight of maintenance and preservation of equipment
    1.C. Configuration management and procedures change reflecting design change 2.D. Dealing with unexpected test results or occurrences 3.D. Deployment of regulatory resource

    Logistics and participation


    Participation was open to experts from NEA and MDEP member countries' nuclear regulatory organisations and their technical support organisations and research organisations. The maximum number of attendees allowed was 70.

    Language of the workshop

    All presentations and discussions were in English, and a good command of the English language was necessary to fully benefit from the workshop.

    Organising committee

    The organisation of the workshop was led by Mr Seunghoon Ahn and Mr Yeon-Ki Chung (MDEP and WGRNR members, KINS, Korea), supported by Mr Janne Nevalainen (WGRNR Chair, STUK, Finland), Mr Fabien Féron (EPRWG member, ASN, France), Mr Lawrence Burkhart (AP1000WG Chair, NRC, USA), Ms Aurélie Lorin and Mr Young Joon Choi (NEA/MDEP).

    Last reviewed: 17 March 2016