Monte Carlo calculations for dose rate at indoors exposed by distributed Cs-137 activities (The 12th International Conference on Radiation Shielding (ICRS-12) and the 17th Topical Meeting of the Radiation Protection and Shielding Division of ANS (RPSD-2012)) -- (Monte Carlo Methods and Applications)

The correlation of dose rates inside of the typical Japanese house to different distributions of Cs-137 activities outside are calculated by using the Monte Carlo code MVP with its attached gamma cross section library for aiming at the planning of decontamination strategies and setting the priorities in order to decrease the amounts of waste soil effectively, which will be disposed and stored for a long time with shield. The study is summarized that (1) the decontamination of the roof is not effective in decreasing the dose rate of indoors when surrounding field is contaminated, (2) the plowing of wide area will decrease the dose rate by one tenth even if the depth is only 5 cm, (3) the dose rate of the 2nd floor is higher than that of the 1st floor in some decontamination cases.