Characterization of Dose Rates and Its Internal Fluctuation Using Frequency Distribution Function of Background Radiation Data

Dinyo Enoch Omosehinmi^1, and Adeseye Muyiwa Arogunjo¹

¹Department of Physics, Federal University of Technology, Akure, Nigeria

Cite this paper:
Dinyo Enoch Omosehinmi and Adeseye Muyiwa Arogunjo. Characterization of Dose Rates and Its Internal Fluctuation Using Frequency Distribution Function of Background Radiation Data. Applied Mathematics and Physics. 2016; 4(1):16-25. doi: 10.12691/amp-4-1-3

Abstract

The use of distribution function in characterization of data technique, to evaluate and estimate dose rates from background radiation in Akure informed this study. The mean and fluctuation in mean of possible exposure due to the members of the general public in Akure was deduced by statistically calculating the mean and fluctuation in mean of 166 sample points. Kindenoo blueGeiger PG-15 detector and Garmin GPSmap 62s were used for the research. The Dose Rate (DR) and its internal fluctuation range between 0.16±0.01μSv/h – 0.37±0.04μSv/h in air, and Annual Effective Dose Equivalent, AEDE between 0.31±0.02mSv/y – 0.71±0.08mSv/y; the estimated mean outdoor AEDE 0.50±0.06mSv/y for members of the general public in Akure is below the UNSCEAR and ICRP recommended 1mSv/y annual exposure dose rate. All the estimated AEDE from measured dose rates at the chosen locations have values far lower than the 100mSv limit of admissible low-level radiation. The skewness and kurtosis of DR distribution is 0.134 and 0.251 with standard error 0.188 and 0.375. The predicted probability function of observing a specific count x in this study is P(x)=0.7826.

Keywords:
background radiation dose rate radionuclide distribution function Akure

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