室内氡浓度与建筑材料表面氡析出率的关系研究

采用RAD7测氡仪对某8层教学楼第5层的房间进行24 h连续测定,测得室内氡浓度范围为5.65~48.7 Bq/m3,不超标。测定结果表明,清晨氡浓度较高,在5:00左右氡浓度达最高值;中午氡浓度较低,11:00左右氡浓度达最低值。经测定房间内墙面抛光瓷砖的表面氡析出率大于地板砖的表面氡析出率。房间室内的氡主要来源于建筑材料表面氡的析出和室外空气,利用氡析出率和室外氡计算的室内氡浓度与测定结果相符。

Exhalation Rate from Building Materials Surface

Indoor radon concentration of a room on the 5th floor of an eight story teaching building was measured by using RAD7 professional radon detector.The range of indoor air radon concentration was 5.65~48.7 Bq/m3 which was not over the standard limit.Results showed the radon concentrations in the early morning were higher,with the highest radon concentration at 5:00 am,while the radon concentrations at noon were lower,with the lowest radon concentration at 11:00 am.The randon exhalation rate from wall polished tile surface was greater than that of floor tile surface.Indoor radon level exposure is caused mainly by radon exhalation of building materials surface and radon in outdoor air.Indoor air randon concentration calculated using the data of radon exhalation rate and radon concentration of outdoor air was agreed well with the results by measurement.