Atmospheric Releases of Air-activated Radionuclides from Medical Cyclotrons: A Comparison among the Models Related to Population Doses

A comparison among three models (Birattari Conic Plume, HotSpot, and NCRP 123 Gaussian distribution) has been carried out concerning the release of air-activated radionuclides during bombardment of a H218O target in a medical cyclotron with two different proton energies: 10 MeV and 18 MeV. Under worst-case meteorological conditions, the diffusion of 13N, 40Cl, 37S, and 41Ar has been investigated. The total amount of induced activation (Bq) during different beam times has been calculated for each isotope, and the three models have been used to assess the dose to the residential population located 100 m from the release point, for a fixed beam current of 100 µA. The results demonstrate that a facility for medical isotope production, even under heavy workload (3,000 µA h-1 wk-1), will not lead to a significant increase in the dose to the surrounding population.