Simulation of long-lived activation products in nuclear reactor biological shield by MCNP and ORIGEN-S

the absorbed dose due to ionizing radiation is a function of three parameters: 1- Time 2- Source 3- Shielding. shielding materials -as any other material- activate when they are exposed to irradiation. The aim of this study is to calculate the attenuation coefficient and investigate shielding properties of different concrete compounds with various aggregates. After that the required time for achieving IAEA anounced clearance levels for these compounds was calculated by ORIGEN-S code.Cs, Co and Eu are important radionucleids in term of determine the required time for achieving clearance levels.