Development of Time Limited Ageing Analyses to Support Continued Safe Operation of Research Reactors

Approximately 50% of the operating research reactors in the world have reached 50 years of age, a significant number of them (about 20% of the total operating reactors) has reached 60 years of operation.  It is of paramount importance that adequate life management programmes (ageing management, modernization, and refurbishment) are established and implemented to ensure maintaining adequate safety margins and availability of reactor-based products and services including production of radioisotopes for medical and industrial applications.
Continued safe operation of research reactors requires amongst others a systematic ageing management programme. Time limited ageing analyses (TLAA) have been developed and widely used by the nuclear power plant community to manage ageing of structures, systems, and components (SSCs) and support decision making for long term operation. Although a number of ageing management activities are increasingly being implemented in the research reactors world-wide, TLAA have largely not yet been identified and developed by the research reactor community. Such analyses are particularly useful for those SSCs of research reactors that are not easily replaceable or where the replacement involves significant cost and effort. TLAA typically allow for enhancing the effectiveness of the ageing management activities  , thus significantly reducing associated costs. There is a need to evaluate TLAAs as a tool to demonstrate that the analysed ageing effects will not adversely affect the ability of the SSCs to perform their   function over the intended period of operation.
This Coordinated Research Project (CRP) aims to  standardize a process to identify, validate, and develop the time limited ageing analyses for selected SSCs of different types of research reactors and to provide case studies in order to effectively manage the ageing effects and build a technical basis to justify the continued operation.