Research on Shielding Performance Measurements of radioactive materials Transportation Package

Some radioactive sources are often used in irradiation industry and radiotherapy, such as Co-60, Cs-137, I -131, P-32, Sm-153, Mo-99, Sr-90, Sr-89 etc. The amount of radioactive sources transportation is large. Recently, a large number of spent fuels also need to be shipped out. In order to keep all doses exposed lower than the limits during the transport of the radioactive materials, some corresponding radiation protection measures must be taken and the radiation shielding performance of radioactive materials package must meet the requirements of GB11806-2004 (Regulations for the safe transport of radioactive material).  The requirements of GB11806-2004 are same with the requirements of IAEA SSR6 (Regulations for the safe transport of radioactive material). Since the state council decree 562(the radioactive goods transportation safety management regulations) issued, the safety supervision of radioactive materials transportation package has been further stressed and implemented in china. The shielding performance measurements of radioactive materials transport package are the important content of supervision. However, some of the problems and difficulties reflected in practice need to be solved. The layout of radioactive sources has a important impact on the monitoring results of the external radiation levels of radiation sources transport container. The neutron dose rate on the surface of spent fuel package is too difficult to be measured precise, the monitoring results are not always reliable while the equipment is not chosen appropriately etc. In this paper, above problems and difficulties were discussed. The monitoring results using different spectrometers were compared and the MCNP runs are done to study the shielding performance measurements of radioactive materials package.