Measurements of the equilibrium factor for 222Rn daughters in dwellings in India.

Pollution Monitoring Section, Bhabha Atomic Research Centre, Bombay, India.
Science of The Total Environment (Impact Factor: 3.16). 01/1991; 99(1-2):49-52. DOI: 10.1016/0048-9697(90)90209-D
Source: PubMed

ABSTRACT As part of an ongoing project to assess the population dose from indoor radon and its daughters in India, a set of parallel measurements was made in more than 150 houses of different types to estimate indoor radon and progeny levels. Time-integrated solid state nuclear track detectors were employed for the measurement of radon concentration and potential alpha energy exposure level. From these values the equilibrium factor (F) between radon and its progeny was estimated for each house. An average F value of 0.39 was obtained.

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    ABSTRACT: Solid-state nuclear track detectors are increasingly being used for the measurement of time-integrated radon levels in dwellings under different conditions. This paper presents the results of Rn measurements in the indoor atmosphere of Manzini Town and the University of Swaziland campus using CR-39 plastic track detectors. The results show that radon concentrations in the indoor atmosphere vary with the ventilation conditions. The books present in a library can also serve as Rn emitters and thus may increase health risks. The equilibrium factor (F) and the effective dose equivalent (Hg) were determined. The recorded values lie below the international guidelines.
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    Nuclear Tracks and Radiation Measurements 01/1993; 22:331-334. DOI:10.1016/0969-8078(93)90079-J