Use of Natural Ventilation to Control Radon in Single Family Dwellings

摘要

The paper discusses an examination of a fundamental assumption in radon mitigation work, that natural ventilation is not very effective in lowering indoor radon levels in buildings. (The mechanism by which ventilation acted to reduce radon levels was considered to be simple dilution; thus a factor of 10 increase in the air exchange rate would be required to reduce radon levels by this same factor.) The examination (in a natural ventilation experiment in a research house) showed that this assumption is fundamentally incorrect. Measuring the pressure field of a basement in conjunction with the building air exchange rate shows that ventilation reduces radon levels two ways: (1) by dilution, and (2) by modification of the pressure field of the building shell. The experiment indicates that effect (2) is much more important than (1)--dilution--and that natural ventilation can cause a much larger reduction in radon levels than was previously believed possible.