Radon decay products precipitators

F varies from 0.1, when only 218Po is present, to unity at equilibrium. Figure 5 shows the changes in the aggregate radon decay-product concentration, the concentration of 218Po, and the variation in F achieved by operating the electrostatic precipitators. The radon decay-product concentration was reduced by more than a factor of 10. 

Figure 5. Radon decay-product and RaA concentrations with equilibrium factor during the use of electrostatic precipitators.

Electrostatic precipitators were effective in reducing the radon decay-product concentration below the reference level, but analysis of the room aerosol indicated that the reduction was largely offset by an increase in lung dose per unit exposure. 

Although physics and chemistry were responsible for the conceptual framework overall, radiochemistry defined the experimental approach and provided much of the initial data. The neutron sources then in use (usually radium or radon [a source of alpha particles] mixed with powdered beryllium) were weak, with the result that the new beta activities were not much stronger than the natural radioactivity of uranium and its decay products. In 1934, the Rome group chemically separated the new activities from uranium by co-precipitating them with manganese and rhenium compounds (both transition metals), which supported the notion that these were... 

Apart from the activity ratios of the radon-222 decay product radionuclides, the residence time of tropospheric aerosols can be derived from the activity ratios of the fission product radionuclides released into the atmosphere during the explosions from nuclear weapons testing or nuclear reactor accidents, such as Sr/ Sr and " Ba/ Sr. These nuclide ratios are considered as nuclear clocks. The applicability of the radionuclide ratios depends on whether steady-state conditions hold at the time and place of measurement and on the kind of sample, whether surface air or precipitation (rain or snow), used for the radioisotope activity determination. 

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