The National Academies of Sciences, Engineering, and Medicine will appoint an ad hoc committee of experts to examine domestic and international developments in radioactive source applications and feasible alternative technologies. In addition, the assessment will use criteria to assess the overall technical feasibility and maturity of those technologies, including the Department of Energy Technology Readiness Level (TRL). Moreover, the assessment of alternative technologies will evaluate their attractiveness and practicality to organizations in consideration of adopting or transitioning to them.