INFLUENCE OF VENTILATION RATE ON INDOOR RADON CONCENTRATION IN A TESTCHAMBER

A methodological approach is proposed in order to identify the sources of indoor radon and the proper remedial actions to be undertaken in h ighly contaminated houses. The application of this methodology to a te st chamber allows the evaluation of the following sources: building ma terials, outdoor air and underlying soil. Estimates are performed by b oth experimental techniques and mathematical modelling. Measurements c arried out inside the test chamber indicate the dependence of radon co ncentration on ventilation and differential pressure between indoors a nd outdoors. The increase in ventilation induces the following effects on radon entry: an increase of entrance from outdoor air and a diminu tion of inflow from underlying crawl-space due to the rise of indoor p ressure that inhibits the upward airflow from the crawl-space.