Dose mapping using MCNP5 mesh tallies.
Rensselaer Polytechnic Institute has a 69.6 GBq (1.88 Ci) (137)Cs source that is used for research, calibration of various instruments, and teaching. Recently it was calibrated using ion chambers. The source and room were also modeled in Monte Carlo N-Particle transport code (MCNP5) to determine if the use of a new feature called mesh tallies produces a dose map in the entire room that agrees with the measured results. The dose rate in the hallway, while the source is exposed, was also calculated. It was found that the dose rates calculated from the MCNP5 are in reasonable agreement with the measured results and theoretical predictions. It was also confirmed that the dose rates where the user often stays during the measurement are well below the annual limits. This project shows that the MCNP5 mesh tallies are useful tool for dose mapping in many operational radiation protection situations.