Study And Hygienic Evaluation On Indoor And Outdoor Radon Concentration In Part Area Of Xinjiang Department Of Labor Hygiene And Environmental Health In Public Health College, Xinjiang Medical University

Objective To investigate indoor and outdoor radon concentration in part area of Xinjiang and activity of the nature radioactive nuclide of 226Ra, 232Th,40K in structural material of Xijiang. Make hygienic evaluation to the data according to the relevant national standards. Methods The concentration of radon and its daughters are measured by track-etch and balloon method. The nature radioactive nuclide of 226R,232Th,40K in structural material of Xijiang are measured by low background Y energy spectrum. Results The mean concentration of indoor radon of Urumqi is 67.3 Bq/m3(n=130) with the 95% confidence interval of 60.3-74.2 Bq/m3 . The mean concentration of radon in underground construction is 141.8 Bq/m3(n=25) with the 95% confidence interval of 68.5-215.1 Bq/m3. The mean concentration of outdoor radon is 23.1Bq/m3(n=21) with the 95% confidence interval of 20.3~25.9 Bq/m3. The mean concentration of indoor radon in Xinjiang is 54.7 Bq/m3(n=259) with the 95% confidence interval of 50.6-58.8 Bq/m3. The mean concentration of outdoor radon in Xinjiang is 21.1 Bq/m3(n=44) with the 95% confidence interval of 20.5-21.7 Bq/m3. The concentration of indoor radon of Xinjiang is higher than that of China (43.9Bq/m3,n=2147) (P<0.05).And the concentration of indoor radon of Urumqi is higher than that of Xinjiang .(P<0.05) The effective annual dose of resident in Xinjiang caused by radon is 65 μ Sv/a. Thechange trend of equation 226Ra in structural material of Xinjiang is granite > color ceramic tile > marble > red brick > perlite > ceramic block > cement of 325 > hollow block > cement of 425> cement of 525 > water mill stone > white cement. Conclusion The mean concentration of indoor radon of Xinjiang is 54.7±11.5 Bq/m3 which is higher than that of China. The concentration of indoor radon in 0.7% dwelling in Xinjiang exceeds the national standard limit (400Bq/m3). Prevention of radon pollution and reduction of radon level can not be ignored. The radioactivity of 3% structural material exceeds the national standard limit (GB6566-2001) . The radioactivity of 23% granite exceeds the standard limit. In order to prevent the health of residents, the radiation prevention and hygienic supervise work should be strengthened for structural material in Xinjiang.