Long-term determination of airborne radon progeny concentrations using LR 115 detectors and the effects of thoron.
The 'proxy equilibrium factor' (F(p)) method has been developed for long-term determination of airborne radon progeny concentrations using LR 115 solid-state nuclear track detectors. In this paper, the effects of (220)Rn on the F(p) method have been studied. The correction to the track density was related to a parameter α which was the ratio of the sum of activity concentrations of alpha-particle emitting radionuclides in the (220)Rn decay chain to the activity concentration of (220)Rn alone. Under commonly encountered circumstances, α could not be smaller than 2. An attempt was made to verify this using the exposure chamber at the National Institute of Radiological Sciences (NIRS), Chiba, Japan. A most interesting observation of α < 2 for very high (220)Rn concentrations and very low equilibrium factors for (220)Rn in the exposure chambers was made. A possible explanation was the substantial deposition of (216)Po under the extreme conditions inside the exposure chambers.
Choi
V W Y
VW
Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Kowloon, Hong Kong.
Ng
C K M
CK
Lam
R K K
RK
Janik
M
M
Sorimachi
A
A
Kranrod
C
C
Nikezic
D
D
Tokonami
S
S
Yu
K N
KN
D000396:Air Pollutants, Radioactive; D016902:Air Pollution, Indoor / Q000032:analysis*; D000465:Algorithms; D000512:Alpha Particles; D004781:Environmental Exposure; D005740:Gases; D006798:Housing; D007564:Japan; D015233:Models, Statistical; D011059:Polonium / Q000032:analysis; D011834:Radiation Monitoring / Q000295:instrumentation*; D011874:Radiometry; D011886:Radon / Q000032:analysis*; D017687:Radon Daughters / Q000032:analysis*; D012306:Risk
D000396:Air Pollutants, Radioactive; D005740:Gases; D017687:Radon Daughters; D011059:Polonium; D011886:Radon