Document Type : Original Article



Introduction: Environmental natural radiation measurement is of great importance and interest
especially for human health. The induction of genetic disorder and cancer appears to be the most
important in an exposed population. Materials and Methods: Measurements of background
gamma rays were performed using a mini-rad environmental survey meter at 25 different
locations around the city of Kermanshah (a city in the west of Iran). The measurements were
also performed at two different time of day one in the morning and the other in the afternoon.
At each location and time measurements were repeated for five times and the mean was
considered as the background dose at that location. Results and Discussions: Comparison
between the measured results in the morning and afternoon has not shown any significant
difference (P > 0.95). The maximum and minimum obtained results were 2.63 mSv/y and
1.49 mSv/y, respectively. From the total measurements at 25 sites mean and SD background
radiation dose to the population is 2.24 ± 0.25 mSv. Conclusion: The mean radiation dose
to the population is about 2.5 times of the world average total external exposure cosmic rays
and terrestrial gamma rays dose reported by UNSCEAR.


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