Assessment of Internal Contamination with Radioactive Iodine for Radiation Workers Two-case Studies

For the purpose of occupational radiation protection against ionizing radiation, it is important to assess radiation risks due to any contamination events. Effective dose equivalent and body organs dose of workers exposed to 131 I have been estimated in this work. For this sake, both MONDAL 2.0 software and Visual Monte Carlo-dose calculation (VMC-dc) programs were applied. The cases under consideration are: 1) an overexposure of 131 I to ten radiation workers. This event happened during a maintenance period at a Korean nuclear power plant (NPP) where I-131 has been released to the reactor building from a primary system opening[1]. 2) The second event has been occurred in a chemical laboratory responsible for the production of radio-iodine 131 I. A release of the radioisotope in the laboratory air has lead to over exposure to one of the workers [2]. In both cases measurement of radiation activity took place with the use of different techniques where no measurements or estimation for organ doses were performed meanwhile.