Simulation of the distribution of radioactive materials in urban areas—radiation protection perspectives based on local conditions and the Swedish legal framework

This study aims to evaluate a realistic scenario to provide deeper insight into potential future events, necessitating a well-prepared and public-supported emergency response to improve resilience against radiological threats and mitigate their impact on public health and safety. The use of a radioactive dispersal device (RDD) in urban areas in Stockholm, Sweden, was simulated using the decision support system LASAIRs (Lagrange Simulation of the Dispersion and Inhalation of Radionuclides). The findings confirm that the urban landscape will influence the distribution of radioactive materials, especially in adjacent areas where the distribution is strongly dependent on the influence of adjacent buildings and other large structures, the surface structures and the presence of strong winds in open fields. The results suggest that radiation concentrations will be dispersed over a local area, with a predicted maximum dose directly associated with the source term input.