Calculation of Shutdown Dose Rate in Fusion Nuclear Science Facility During a Proposed Maintenance Scheme

In this work, a preliminary assessment of the shutdown dose rate (SDR) in the latest Fusion Energy Systems Studies–Fusion Nuclear Science Facility conceptual design was calculated for one sector at different maintenance stages. The third operational phase, deuterium-tritium for 2.75 years, was considered to define the neutron source and the Rigorous 2-Step workflow was used. SDR levels were obtained at times that correspond to major maintenance operations and were found to be above 10⁵ µSv/h, which necessitates robotic handling of all maintenance operations.