GMサーベィメーターによる地殻変動観測坑内空気中のラドン濃度の測定
1990 年 43 巻 1 号 p. 111-120
詳細
1990 年 43 巻 1 号 p. 111-120
An automatically measuring system with GM-survey meter and micro-computer was developed for γ-ray observation. The system shows sufficient stability during two years observation of γ-rays in the tunnel for crustal movement observation. Based on comparison of radon measurement using flow-type ionization chamber and γ-ray spectroscopy using Nal (T1) scintillation counter, it was especially clarified that the system was available for measurement of radon concentration in tunnel air, since radon concentration is 300-40, 000 times in tunnel air higher than in outdoor air. In addition, it has also become clear that a simultaneous measurement using several instruments is desirable to make a precise survey.
