Statistical Analyses of the Data on Occupational Radiation Exposure at JPDR

Abstract

In the statistical analyses of the data on occupational radiation exposure at JPDR, statistical features were obtained as follows.
(1) The individual doses followed log-normal distribution.
(2) In the distribution of doses from one job in controlled area, the logarithm of the mean (μ) depended on the exposure rate (r(mR/h)), and the σ correlated to the nature of the job and normally distributed. These relations were as follows.
μ=0.48ln r-0.24, σ=1.2±0.58
(3) For the data containing different groups, the distribution of doses showed a polygonal line on the log-normal probability paper.
(4) Under the dose limitation, the distribution of the doses showed asymptotic curve along the limit on the log-normal probability paper.