Zdzislaw ZuchoraANWAR BULAYHAN ALMUTAIRI2022-05-192022-05-19https://drepo.sdl.edu.sa/handle/20.500.14154/14464Radiation protection aspects which must be considered, that relevant to installation a medical cyclotron are discussed. Firstly, A general overview is given of the radiation hazard that associated with operation the cyclotron in a hospital, and general safety requirements. Next, Estimation the neutron and gamma radiation fields around the cyclotron area. Two types of a low cyclotron energy are considered: Cyclotron RDS 111 self-shielded and TR19 cyclotron in vault. induced radioactivity in accelerator components and shielding walls and cyclotron shielding decommissioning are briefly discussed . Finally, The results of calculations the necessary shielding in some detail for the of RDS 111 self-shielded are discussed. As The neutron and gamma dose rates have been estimated to define the thickness of the total necessary shielding, and the concrete is selected as the main shielding material. The layout bunker for the installation dimensions for replacing the linac accelerator with the new self-shielded medical cyclotron is presented in this research which can be applied in UCHG's radiotherapy department for establish a new PET facility.en