Activities on risk-informed in-service inspection within the ENIQ network

The European Network for Inspection and Qualification (ENIQ) is a utility-driven network that works towards a harmonised European approach on reliable and effective in-service inspection (ISI), primarily in the nuclear power industry. The ENIQ has two task groups: a Task Group on Qualification (TGQ), which works on issues related to the qualification of non-destructive evaluation (NDE) systems, and a Task Group on Risk (TGR), which is focused on risk-informed in-service inspections (RI-ISI).

After publishing the European Framework Document on RI-ISI in 2005, ENIQ TGR has been working on producing more detailed recommended practices and discussion documents on several RI-ISI related issues. The following reports have been issued: (1) Discussion document on the role of ISI within the philosophy of defence in depth; (2) Recommended practice on verification and validation of structural reliability models (SRMs) and associated software to be used in RI-ISI programmes; (3) Recommended practice on guidance on expert panels in RI-ISI; (4) Discussion document on application of RI-ISI on reactor pressure vessel.

Work is ongoing to develop a discussion document on the updating of RI-ISI programmes and new initiatives were recently launched to study topics such as what magnitude of risk reduction is reasonable to achieve through ISI, how to set inspection targets following the selection of ISI sites and how to produce detection probability estimates for ISI. In addition, TGR has been active in initiating international projects linked closely to its work, such as the JRC-OECD/NEA co-ordinated RI-ISI benchmark exercise (RISMET) and the project on the relation between inspection qualification and RI-ISI.

The aim of this paper is to review and explain these activities of ENIQ TGR.