Radon concentration measurement in citizens home and school buildings along the Median Tectonic Line and Ina valley

采用被动型（CR-39）氡气监测仪对茨城市工业大学教室内的氡浓度进行了测量。我们还让学生们用同一类型的氡监测仪测量他们家里的房间。这个实验使他们认识到他们身体周围确实存在天然放射性同位素。我们对茨城市工业大学计算机中心的氡气浓度进行了测量，当关闭通风机时，氡浓度高达600-900 Bq/m3[EEC]。我们与NRI和东京大学的专业氡研究人员合作，调查了我们学校计算机中心的空气特征。氡及其子代、Po-218、Pb-214、Bi-214的浓度、当量氡浓度、气溶胶直径分布、游离氡比、通风量、通风机和空调过滤器的特性等。空调运行导致游离氡率增加，。因此，我们没有特殊的设备，但这个实验强调了学生和老师对我们身体周围天然放射性同位素存在的兴趣。我们在各个学校进行了实验，特别是在中构造线和伊纳河谷沿线的学校。

We measured the radon concentrations in classroom of Ibaraki National College of Technology, with passive type (CR-39) radon gas monitor. We also made the students to measure their room in their homes with same type radon monitors. This experiments cause them to recognize the actual existing of natural radioisotopes around their bodies.We measured the radon gas concentration in the computer center of Ibaraki National College of Technology, When the ventilator is off, the radon concentration increase up to 600-900 Bq/m3[EEC]. We collaborate the professional radon researchers, NRI and the University Tokyo, to investigate the characteristics of the air in the computer center of our school.The concentration of radon and her progeny, Po-218, Pb-214, Bi-214, equivalence radon concentration, distribution of diameter of aerosol, ratio of free radon, ventilation rate, characteristics of filters of ventilator and air conditioner, so on. Operation of the air conditioner cause increase the rate of free radon,. Thus, we have not special equipment, but this experiment emphasize the interest to student and teachers the existence of natural radio isotopes around our bodies. We carried on this experiment in various schools, especially in the schools along the Median Tectonic Line and Ina Valley.