Shielding analysis for the treatment room with an eye beam line at the Proton Therapy Center in Prague

The analysis was performed in the context of radiation protection and current legislative requirements. The main sources influencing radiation field in the treatment room and its surroundings were identified. The angular-energy distributions of the secondary particles were modelled for proton beam interactions with selected materials and for the relevant proton beam energy range. The MCNPX 2.6.0 Monte Carlo code and the Bertini hadron interaction model were employed. Angular-energy neutron spectra were used to estimate the annual dose equivalent from selected secondary particle sources in the relevant parts of the PTC. The dose equivalent levels were also used to verify the adequacy of the shielding barrier dimensions. (orig.)