活性炭と地下水を利用した，自然放射線を測定する安価で安全な教育用実験

抄録

Although we had previously developed several kinds of experiment for radiation education using natural spring water, the sites for spring water whose radioactivity was high enough for the experiment were limited in Japan. In the present work, we explored the possibility of using underground water, which can be easily obtained in many places. By using a plastic bottle and a charcoal filter cartridge, a safe and inexpensive apparatus was developed for collecting low concentration of radon in water phase in a short time. Our method makes it possible to observe the decay of radon and the production of its offspring species even if we use ordinary tap water coming from an underground water source.