A new method of continuous measurements of radon (Rn222) and thoron (Rn220) in the atmosphere
Israël, G. W.
- Publisher: Co-Action Publishing
(issn: 1600-0870, eissn: 0280-6495)
To achieve continuous measurements, an aspiration process was developed, permitting a direct measurement of the radon (Rn222) and thoron (Rn220) contributions to the ionization. After passing through a filter that holds back all aerosols and radon and thoron daughter ions, the air streams through an approximately 300 liter ionization chamber. The current, measured with a vibrating reed electrometer, is composed of three parts: background, radon contribution and thoron contribution, with each component resolved by appropriate methods. The sensitivity limit amounts to some 0,8·10−14 c/1 for radon and 0,5·10−14 c/1 for thoron with a resolution time of about 220 sec. This report deals with the principle of measurement and its use for the determination of the radon and thoron content of the lower atmosphere.DOI: 10.1111/j.2153-3490.1966.tb00269.x