The design of radiation shielding was evaluated for a proton therapy facility being established at the National Cancer Center in Korea. The proton beam energy from a 230 MeV cyclotron is varied for therapy using a graphite target. This energy variation process produces high radiation and thus thick shielding walls surround the region. The evaluation was first carried out using analytical expressions at selected locations. Further detailed evaluations have been performed using the Monte Carlo method. Dose equivalent values were calculated to be compared with analytical results. The analytical method generally yielded more conservative values. With consideration of adequate occupancy factors annual dose equivalent rates are kept <1 mSv y(-1) in all areas. Construction of the building is expected to be completed near the end of 2004 and the installation of therapy equipment will begin a few months later.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.