A survey of terrestrial γ radiation level in high background radiation area of Yangjiang,Guangdong

Objective: To obtain the levels of terrestrial γ radiation in the high background radiation area (HBRA) of Yangjiang and its control area of Enping. Methods: A total of 112 houses in the HBAR and 147 houses in Enping were selected through multi-stage sampling. The in-room and at-gate γ radiation levels were measured by a survey meter (FH40 G + FHZ672 E-10). Meanwhile, the levels of outdoor γ radiation of selected villages were also measured. Results: The indoor and outdoor γ radiation levels in the HBRA were (0.36 ± 0.06) μSv/h and (0.16 ± 0.06) μSv/h, while the levels in Enping were (0.13 ± 0.05) μSv/h and (0.09 ± 0.03) μSv/h, respectively. The levels of indoor and outdoor γ radiation in the HBRA are about 3 and 2 times of those in Enping, respectively, and the differences were statistically significant. The levels of indoor γ radiation in the HBRA were (0.34 ± 0.05) μSv/h and (0.38 ± 0.05) μSv/h for the new houses and the old houses, respectively. While the values in the control area were (0.18 ± 0.02) μSv/h and (0.09 ± 0.03) μSv/h, respectively. The differences between the new and old houses were both significant in the two areas. Conclusion: The level of γ radiation in the HBRA of Yangjiang is much higher than that of control area, but the difference between the two areas is decreasing. (authors)