Abstract: Based on the monitoring data of ¹⁴C in the surrounding air of the nuclear base of China Nuclear Power Institute, from 2014 to 2017, the effective dose to be accumulated for key residential groups in various ways was roughly estimated. The conclusion shows that the difference of ¹⁴C activity concentration in the air between the comprehensive building and the labor union of Nanba is statistically significant; the difference of ¹⁴C activity concentration in the air between the comprehensive building and the water works of Mucheng is statistically significant; while the difference of ¹⁴C activity concentration between the labor union of Nanba and the water works of Mucheng is not statistically significant. The above discussed results indicat that emitted ¹⁴CO₂ diffuses and mixes rapidly in the air. The average annual ¹⁴C intakes of adults, teenagers, children and children in the residential groups near the comprehensive building were 40.55,40.52,29.10 and 19.80 kBq/a, respectively, and the relevant annual effective doses to be accumulated were 23.31, 22.91, 23.08 and 19.44 μSv/a. The maximum effective dose of ¹⁴C in adult group was 23.31 μSv/a, but it only accounted for 9.3% of the target dose (0.25 mSv). It can be concluded that the influence of ¹⁴C on the surrounding environment of nuclear base is very small under normal operation conditions of the nuclear base.

Key words: ¹⁴C, nuclear base, dose evaluation