Horizon Nuclear Power intends to build advanced boiling water reactors at Wylfa and Oldbury in the United Kingdom based on the Hitachi-GE (Hitachi) design. In accordance with U.K. policy for new nuclear build, Hitachi, as the reactor designer, is the requesting party to the Generic Design Assessment (GDA), during which the reactor design will be reviewed by the Office for Nuclear Regulation and the Environment Agency. An important step in the GDA process is to demonstrate the viability of the approach developed by Hitachi-GE for the assessment and justification of smart devices. This was done by means of pilot studies of safety class 1 (SC1) and SC2 devices. This paper describes the scope, criteria, process, and approach for the SC1 pilot study and summarizes the results of the study.