DS561 - Ageing Management and Development of a Programme for Long Term Operation of Nuclear Power Plants

Status: STEP 4

Revision von SSG-48

Beteiligte IAEO-Komitees: NUSSC, WASSC

Specific Safety Guide

Zurück zur Übersicht "In Entwicklung befindliche Safety Standards"

In recent years an increasing number of States have decided to license continued operation of nuclear power plants beyond their initial extension period, or to further extend their lifetime based on 10-year periodic safety reviews. In 2018 SSG-48 was published and has since been used for Safety Aspects of Long Term Operation (SALTO) missions, the International Generic Ageing Lessons Learned (IGALL) programme and by individual nuclear power plants (NPPs) in developing and implementing ageing management activities and preparing for long term operation (LTO). Additionally, States and regulatory bodies also use SSG-48 to develop and improve regulations and guidance related to ageing management and LTO. As a result, these activities have generated considerable information and experience indicating areas where SSG-48 can be further improved or supplemented.

A revision to update SSG-48 would better support the users, e.g. the operating organizations and regulatory bodies by:

− Better addressing the existing recommendations, e.g. for implementation of ageing management for active components, assessment of ageing management effectiveness, extending the recommendations in several places based on experience in its use;

− Supplementing the currently addressed topics with additional topics, e.g. preparation for a subsequent LTO, activities to be conducted in the subsequent LTO period to maintain the proper level of ageing management, coordination of ageing management on the plant level, ensuring human resources for LTO, safety aspects of supply chain management for LTO, compliance with current regulations, codes and standards and obsolescence of knowledge.

The general scope of the revised publication will remain unchanged. Some identified revision aspects for SSG-48 (these aspects will be considered and discussed during the revision process, but not necessarily all will be used) are:

• General review of the publication and the core ageing management topics (scope setting, ageing management review, AMPs, time limited ageing analyses - TLAAs);
• Experience from subsequent LTO preparations:
  • How to handle if regulatory requirements are not sufficiently detailed;
  • Knowledge transfer of experts between LTO and subsequent LTO;
  • Long term (investment) strategy for safety improvements;
  • Timely decision making;
  • Disappearing service providers;
  • Disappearing (or obsolescence of) standard basis, including the resulting obsolescence of technical specifications;
  • Lack of sufficient qualified suppliers: lack of competition and its potential impact on safety.
• Ageing management in the early stage of operation, during design, construction, commissioning: SSG-48 provides limited recommendations, but possible inputs can be:
  • Details on expectation for TLAAs and scope setting in early design-stage;
  • More guidance on material selection criteria (e.g. corrosion and radiation resistance) and effective methods for establishing baseline degradation data;
  • Chemistry control of testing fluids against corrosion in long term;
  • Handling and preservation of equipment at workshops and site.
• Recommendations on how to better integrate human resources strategy, knowledge management and competence management aspects and delivery plans into the LTO programme especially considering the increased need for qualified and experienced staff for performing design upgrades and modifications for LTO and how HR strategy should be extended to LTO and many others (see 32 points in Annex to this DPP).