Study On Evaluation Of Granite Radon Exhalation Rate And Indoor Radon Radiation Risk

Family decoration is a pursuit of the quality of human life. With the rapid growth of economy and society, the increasingly demand of the family decoration quality and it is just as important as decorative material of modern people. A radioactive gas "Radon" was decayed by radionuclide 226 Ra which was contained of natural stone(granite). The relevant literature showed that lung cancer incidence was increased to 19%-31% when average radon concentration increased 100Bq/m3.A lot of granite as ornaments was used unscientific will be affected by the radon radiation pollution. Therefore, this paper selects the market commonly used 18 kinds of granite measuring radon exhalation rate on it, and study the relationship between the radon exhalation rate and indoor radon concentration, the study of indoor radon radiation risk assessment method, the risk assessment of indoor radon radiation.This paper selects 18 kinds of the common market of granite measuring radon exhalation rate, 18 types of granite radon exhalation rate is in the range of 7.05×10-3Bq/m2.s~0.35×10-3Bq/m2.s, the average value is 2.04×10-3Bq/m2.s, slightly higher than that of other ordinary building materials. Which is the highest since the middle of Guangxi Cenxi red was 7.05×10-3Bq/m2.s, the rock is biotite K-feldspar granite, particle size of coarse grain; the lowest is produced in Fujian general red 0.35×10-3Bq/m2.s, the lithology of K-feldspar granite, grain size is coarse grain. Granite radon exhalation rate size and 226 Ra nuclide, lithology,alteration and geological age.By choosing a stone factory use the RAD7 field measurement of indoor radon concentration measurement instrument, the average radon concentration was 34.75Bq/m3.Indoor radon concentration and air pressure, temperature, relative humidity and ventilationrate, relationship formula)382.2152.0209.0()(10RHBar T V AJVC C V i vii--++=?=lll析.Through the establishment of indoor radon radiation risk evaluation index evaluation system is established, by qualitative and semi quantitative analysis of indoor radonradiation risk, the risk of indoor radon radiation dose was H * D= in workers exposed toradon radiation zone time E * body condition L. The empirical analysis using this evaluation system, the effective and scientific results, to provide scientific basis for selection of stone processing plant in occupation health protection and ordinary families decoration materials.