Investigation of environmental natural penetrating radiation level in Xinjiang

The methods and results of the investigation on natural penetrating radiation level in Xinjiang are presented. 74025 x 25 km-grid measuring points were set uniformly up, with 884 densely measuring points of different types added. The results show that: (1)The point-weighted, area-weighted and population-weighted average value of natural γ radiation dose rate for field is 5.81, 5.94 and 5.76 x 10-8 Gy·h-1, respectively; (2)The point-weighted average value of natural γ radiation dose rate for road is 5.63 x 10-8 Gy·h-1; (3)The point-weighted and population-weighted average value of natural αradiation dose rate inside buildings is 9.92 and 9.86 x 10-8 Gy·h-1, respectively; (4)The point-weighted and population-weighted average value of the dose rate inside buildings from cosmic ray is 3. 90 and 3.55 x 10-8 Gy·h-1. and outside buildings is 4.40 and 4.01 x 10-8 Gy·h-1, respectively; (5)The point-weighted and population-weighted average value of natural penetrating radiation dose rate inside buildings is 13.82 and 13.42 x 10-8 Gy·h-1, outside buildings is 10.22 and 9.77 x 10-8 Gy·h-1, respectively; (6)The annual effective dose equivalent from natural γ radiation, cosmic ray and natural penetrating radiation is 0.53, 0.32 and 0.86 mSv, respectively; and correspondingly, the annual collective effective dose equivalent from natural penetrating radiation is 1.13 x 104 man·Sv