Surface Radon Exhalation Rates of Building Material and Soil Affect on Indoor Air Radon Concentration

By using RAD7 professional radon monitor which detecting data is reliable, selecting a one-story cottage in Shenzhen city area as the research object, the measurement results showed the radon concentration in the soil around the one-story cottage area was low background; the soil surface radon exhalation rate of soil was higher and was about two times that of cement floor of the room which indicated that the soil is the largest source of indoor radon; the surface radon exhalation rate of cement floor was higher than that of ceramic tile floor and was about 4 times that of the ceramic tile floor. The indoor radon concentration in the room covered with cement floor was higher than that of the room covered with ceramic tile floor due to the larger surface radon exhalation rate of cement floor. Therefore, in order to reduce indoor radon concentration, the laying floor material with low surface radon exhalation should be selected and windows should be kept open for ventilation.