This third topical report is concerned with the effectiveness of pressure boundary component reliability and integrity management (RIM). Specifically, this report addresses operating experience insights related to less-than-adequate (LTA) RIM and its potential safety and operational impacts. The term LTA-RIM is defined as events where degradation has progressed beyond acceptable limits in systems, structures or components (SSCs) that have a RIM Programme. These LTA-RIM events have some safety significance. In this topical report the LTA-RIM definition is broadened to also include events where a RIM Programme has resulted in a false positive; that is, it has identified degradation that either didn’t exist or was not close to violating acceptance criteria. While such events needlessly expend resources and could be considered LTA-RIM from an economic perspective, they do not have any safety significance.
Additionally, this report addresses selected international practices with respect to pressure testing, leak detection, ISI including NDE, and performance demonstration initiatives to improve the reliability of NDE techniques. The purpose of integrity management is to prevent the occurrence of piping through-wall leaks as well as to monitor passive metallic component degradation. RIM Programme utilises risk insights to augment or enhance existing deterministic integrity management programme. Through a systematic examination of the operating experience as recorded in the CODAP event database, the field experience with the different RIM strategies is evaluated in order to draw qualitative and quantitative insights about integrity management reliability. This topical report also includes an introduction of an approach to evaluate the effect of different integrity management strategies on pressure boundary component reliability.