Survey of [sup 222]Rn concentrations in the air of a tunnel located in Nagano City using the solid-state nuclear track detector method

Journal Article · Thu Jul 01 04:00:00 EDT 1999 · Health Physics

DOI:https://doi.org/10.1097/00004032-199907000-00009· OSTI ID:6378169

Muramatsu, H; Hasegawa, N; Misawa, C; Minami, M; Tanaka, E; Asami, K; Kuroda, C; Kawakami, A ^[1]

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1. Shinshu Univ., Nagano (Japan). Dept. of Chemistry

The survey of [sup 222]Rn concentration in the air of tunnels constructed during World War II has been performed using a solid-state nuclear track detector technique. For the practical application of this technique t the determination of [sup 222]Rn concentrations in air, some basic properties were experimentally examined on the cellulose nitrate film, Kodak LR 115 type II. The calibration coefficient of the cellulose nitrate film used is determined from a correlation between the [sup 222]Rn concentration in air and the observed number of perforated etched tracks for widespread radon concentrations. The slope of the linear relationship observed yields a calibration coefficient of (0.00209 [+-] 0.00018) tracks cm[sup [minus]2] (Bq m[sup [minus]3] h)[sup [minus]1]. From the survey of [sup 222]Rn concentration in the air of tunnels, the concentration of several thousand Bq m[sup [minus]3] was observed at the inner most area of the tunnel, and the seasonal variation was clearly observed. The exponential distribution of radon concentration as a function of distance from the openings of the tunnel suggests that the radon concentration in the tunnel is basically governed by diffusion and mixing of radon gas with air.

• OSTI ID: 6378169
• Journal Information: Health Physics, Journal Name: Health Physics Vol. 77:1; ISSN HLTPAO; ISSN 0017-9078
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540130* -- Environment
Atmospheric-- Radioactive Materials Monitoring & Transport-- (1990-)
AIR POLLUTION
ALPHA DECAY RADIOISOTOPES
DAYS LIVING RADIOISOTOPES
ECOLOGICAL CONCENTRATION
EVEN-EVEN NUCLEI
HEAVY NUCLEI
ISOTOPES
MEASURING INSTRUMENTS
MONITORING
NUCLEI
POLLUTION
RADIATION DETECTORS
RADIATION MONITORING
RADIOECOLOGICAL CONCENTRATION
RADIOISOTOPES
RADON 222
RADON ISOTOPES
SEASONAL VARIATIONS
TUNNELS
UNDERGROUND FACILITIES
VARIATIONS