Justification of Smart Sensors for Nuclear Applications

This paper describes the results of a research study sponsored by the UK nuclear industry into methods of justifying smart sensors. Smart sensors are increasingly being used in the nuclear industry; they have potential benefits such as greater accuracy and better noise filtering, and in many cases their analogue counterparts are no longer manufactured. However, smart sensors (as it is the case for most COTS) are sold as black boxes despite the fact that their safety justification might require knowledge of their internal structure and development process. The study covered both management aspects of interacting with manufacturers to obtain the information needed, and the technical aspects of designing an appropriate safety justification approach and assessing feasibility of a range of technical analyses. The analyses performed include the methods we presented at Safecomp 2002 and 2003.