METHOD FOR MEASURING RADON AND THORON IN AIR

摘要

A novel method for measuring airborne radon and thoron capable of separately measuring radon and thoron with high sensitivity, having a small-sized device structure, and free of the influence from its measurement environment. In the method, by measuring Cherenkov light generated when airborne radon and thoron are adsorbed to an absorbent and then ² rays emitted in process of disintegrations of radon and thoron pass through the absorbent, radon and thoron are measured. Based on a decay time of the Cherenkov light, a mixture ratio between radon and thoron is measured. As the absorbent, porous glass is preferably employed which is provided with fine pores of 0.3 to 30nm in diameter.