The goal of this publication is to provide the latest information on ageing, obsolescence and performance monitoring of those items of instrumentation and control (I&C) equipment that are classified as safety equipment and/or safety related equipment, are operated in harsh environments in NPPs, and are important to plant life extension not only for normal operation but also, and more importantly, for post-accident service. In achieving this goal, this publication identifies the key I&C components of interest that are expected to function well throughout the life of a plant, including the extended life.