摘要
[Objective] The research aimed to monitor and evaluate indoor radon concentration in one district of Xi＇an City. r Method] In order to master the effective dose per year caused by natural radiation to local residents, the investigation about the level of indoor radon in one district of Xi＇an was developed. Based on the proper monitoring scheme, some typical living rooms were sampled. Through the measurement result, the effects of different factors on radon concentration were obtained. Finally, the radon concentration was transferred into the effective dose per year of local residents. [ Result] Indoor radon concentration in the district was during 49.680 -128.856 Bq/m3, and average concentration in each building was within 100 Bq/m3, which belonged to normal range. When sunny day became rainy day, radon concentration firstly had a rise trend. If continuous rainy weather appeared, indoor radon concentration gradually declined. When other conditions were same, indoor radon concentration under window closing was significantly higher than that under window opening. Indoor radon concentration had a decline trend from 13：00 to 20：00 and a rise trend from 01：00 to 06：00. Condusion The district belonged to radon safety house. To protect residents＇ health to the maximum extent, according to transfer change rule of the radon, window should be opened to ventilate in the morning when radon concentration was higher.
[Objective] The research aimed to monitor and evaluate indoor radon concentration in one district of Xi＇an City. r Method] In order to master the effective dose per year caused by natural radiation to local residents, the investigation about the level of indoor radon in one district of Xi＇an was developed. Based on the proper monitoring scheme, some typical living rooms were sampled. Through the measurement result, the effects of different factors on radon concentration were obtained. Finally, the radon concentration was transferred into the effective dose per year of local residents. [ Result] Indoor radon concentration in the district was during 49.680 -128.856 Bq/m3, and average concentration in each building was within 100 Bq/m3, which belonged to normal range. When sunny day became rainy day, radon concentration firstly had a rise trend. If continuous rainy weather appeared, indoor radon concentration gradually declined. When other conditions were same, indoor radon concentration under window closing was significantly higher than that under window opening. Indoor radon concentration had a decline trend from 13：00 to 20：00 and a rise trend from 01：00 to 06：00. Condusion The district belonged to radon safety house. To protect residents＇ health to the maximum extent, according to transfer change rule of the radon, window should be opened to ventilate in the morning when radon concentration was higher.
