222Rn Concentration In Air Research Articles

Preliminary Measurements of Indoor Radon in Ljubljana, Yugoslavia

Abstract In Ljubljana, the capital of Slovenia, one of six Yugoslav republics, 28 houses were selected according to their size, age and construction material, as sampling points to measure indoor air 222Rn concentrations. Air samples were taken every three months and analysed for 222Rn. Radon was isolated from air contained in a 1.2 dm3 sampling glass ampoule, transferred to a scintillation cell and counted. In some homes radon was measured under different microclimatic conditions. In addition outdoor air was surveyed in winter during a temperature inversion when increased radon concentration is expected in a mass of stagnant polluted air. The results obtained have not been quantitatively elaborated. They merely show a preliminary picture of indoor radon levels in Ljubljana and as such are a good base for a planned nationwide radon monitoring programme.

Preliminary Measurements of Indoor Radon in Ljubljana, Yugoslavia

In Ljubljana, the capital of Slovenia, one of six Yugoslav republics, 28 houses were selected according to their size, age and construction material, as sampling points to measure indoor air 222Rn concentrations. Air samples were taken every three months and analysed for 222Rn. Radon was isolated from air contained in a 1.2 dm3 sampling glass ampoule, transferred to a scintillation cell and counted. In some homes radon was measured under different microclimatic conditions. In addition outdoor air was surveyed in winter during a temperature inversion when increased radon concentration is expected in a mass of stagnant polluted air. The results obtained have not been quantitatively elaborated. They merely show a preliminary picture of indoor radon levels in Ljubljana and as such are a good base for a planned nationwide radon monitoring programme.

A Bayesian analysis or scientific judgment of uncertainties in estimating risk due to 222Rn in U.S. public drinking water supplies.

The elements which contribute to the range of values or uncertainties for the lifetime risk and dose equivalent due to 222Rn in U.S. public drinking water supplies are estimated and discussed here. From imperfect scientific knowledge, reasonable upper and lower bounds are placed on these estimates through the use of a semiquantitative Bayesian approach to uncertainty analysis. The factors considered are: occurrence of 222Rn in drinking water, indoor air 222Rn concentrations as a function of drinking water concentration, equilibrium state of the progeny, fraction of daughter products attached to aerosol particles, anatomical and dosimetric variables, epidemiological studies and choice of latency period, plateau period and effects of age. For Rn in U.S. public drinking water supplies, it is estimated that the best estimate for the lifetime lung cancer risk factor is 5 X 10(-9) excess cases of lung cancer per becquerel of Rn per m3 of water (2 X 10(-7) excess cases of lung cancer per picocurie of Rn per liter of water), with an estimated range between 2 X 10(-9) and 2 X 10(-8) excess cases per becquerel of Rn per m3 of water (5 X 10(-8) and 7 X 10(-7) excess cases per picocurie of Rn per liter). The best estimate of the lifetime population risk due to 222Rn in U.S. public drinking water supplies is estimated to be 6,000 excess lung cancers, with a reasonable range of 1,000 to 30,000.

Some basic studies on the absolute determination of radon concentration in the air by a cellulose nitrate track detector

Some basic studies were carried out on the Kodak LR 115 film for the determination of the 222Rn concentration in air using a cellulose nitrate track detector. The factor was obtained which converts the number of perforated tracks registered on a unit area of the detector film to the 222Rn concentration in a unit volume of air. Theoretical equations were derived for the special case of detecting only perforated etched tracks in a thin cellulose nitrate film. The experimental and the theoretical conversion factors are compared and discussed. The effective critical energy and the bulk etching rate were found to be 2.87 MeV and 0.046 μm min −1, respectively, when the film was etched for 160 min using 10% (w/v) NaOH solution at 60°C.