Review of dose criteria for transportation of packages in Korea

Radioactive materials packages are classified into Type-L, Type-IP, Type-A, Type-B, Type-C, Fissile material and Uranium Hexafluoride packages in Korea. Transportation of packages may result in radiation dose to nearby residents. In order to transport packages, it is necessary to establish radiological criteria. In Korea, dose criteria were established as for Type-L, Type-A, Type-B(U) and Type-C packages. The objective of this study is to review the dose criteria for the packages and packaging in Korea. In Korea, dose criteria for the packages and packaging is specified in Nuclear Safety and Security Commission Notice(NSSC) 2017-56. Dose level under routine conditions of transport shall not exceed 2mSv/h at surface, and 0.1mSv/h at 2m from packages or overpacks. For Type-L package, dose level at surface shall not exceed 5μSv/h which is requirement for the Type-L packaging. The packaging Type-B and Type-C have to meet the requirement 10mSv/h at 1m from the surface of the package after specified test which is to ensure the package retain sufficient radiation sheilding in the accident conditions. The worldwide countries applies IAEA rationale and regulations for the safe transport of radioactive material. However, differences with the laws and regulation systems for safe transport packages of each countiries were identified. IAEA recommanded radiation dose rate level by following reason. For excepted package, the 1961 Edition of the Transport Regulation set in 0.1mSv from 0.15mSv which is a radiation detection limit with sensitive X-ray film. For Type-A package, 2mSv/h at surface is derived calculatively by considering transport index and criticality safety index. For Type-B(U) package, recommanded level would retain sufficient shielding to ensure with the maximum radioactive contents that package is designed to contain. For Type-C package, provides similar levels of protection for the air mode when compared to Type-B(U) package in a severe surface mode accident.This study reviewed the dose criteria and rationales of other countries and IAEA Regulation for the Safe Transport. Based on this information, it will contribute to improve the regulatory system in accordance with the transportation of radioactive material in Korea. This work was supported through the KoFONS using the financial resource granted by NSSC.(No.1805016).