Measurements of thoron progeny concentration using apotential alpha-energy monitor in Japan

Journal Article · Thu Jun 01 04:00:00 EDT 1995 · Health Physics

DOI:https://doi.org/10.1097/00004032-199506000-00013· OSTI ID:369951

Yamasaki, T ^[1]; Iida, T ^[2]

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1. Chubu Electric Power Company, Inc., Nagoya (Japan)
2. Nagoya Univ. (Japan)

It is reported that thoron concentration in Japanese dwellings may be higher than in other dwellings. Therefore, in order to assess the risk for indoor thoron progeny, the portable potential alpha-energy monitor has been developed. The monitor detects alpha-particles from the {sup 212}Po collected on the filter using a piece of cellulose nitrate film. The detection efficiency of the alpha-particles has been estimated by Monte Carlo calculation. From the results of measurements, the mean indoor thoron progeny concentration in the dwellings was 1.5 Bq m{sup -3} (EC{sub Tn}), and ranged from 0.04 to 8.2 Bq m{sup -3}. The effects of three typical interior walls (soil-based plaster, concrete, and modern materials) on the thoron progeny supply were considered. The mean annual effective dose equivalent was 0.45 mSv. 13 refs., 5 figs., 1 tab.

• Sponsoring Organization: USDOE
• OSTI ID: 369951
• Journal Information: Health Physics, Journal Name: Health Physics Journal Issue: 6 Vol. 68; ISSN HLTPAO; ISSN 0017-9078
• Country of Publication: United States
• Language: English

Related Subjects

56 BIOLOGY AND MEDICINE
APPLIED STUDIES
66 PHYSICS
ALPHA DETECTION
ALPHA PARTICLES
DOSE EQUIVALENTS
HOUSES
JAPAN
PROGENY
RADIATION MONITORING
RADON 220
RADON 222
RISK ASSESSMENT
WALLS