  In the first paper of this series, we showed that the ratio c of individual
dose to ambient dose did not change with time in Date City, Fukushima
Prefecture, after the Fukushima Daiichi Nuclear Power Plant accident. The
purpose of the present paper, the second in a series, is to estimate the
lifetime doses of the Date City residents, based on continuous glass badge
monitoring data, extrapolated by means of the ambient-dose-rate reduction
function obtained from the airborne monitoring data. As a result, we found that
the mean additional lifetime dose of residents living in Date City is not
expected to exceed 18 mSv. In addition, effects of decontamination on the
reduction of individual doses were not evident. This method of combining
individual doses and the ambient doses, as developed in this study, has made it
possible to predict with reasonable certainty the lifetime doses of residents
who continue to live in this radiologically contaminated area.
