Reduction of Indoor Radon by Air Cleaning—Case Study

Abstract

A field study was conducted over an intermittent period of 2.5 years to determine whether air cleaning, using a portable high efficiency particulate air filter air cleaner with an activated carbon filter, was a viable method of reducing indoor radon levels. Past studies showed that air cleaners could reduce radon and/or radon progeny concentrations. The data collected in this study showed that the air cleaner did not reduce radon levels and so was not an effective mitigation device. The data also showed that above radon levels of 6 pCi/L there was a strong positive linear correlation to moisture content. Below 6 pCi/L there was essentially no correlation. Radon concentrations were determined using EPA approved commercial test kits that were occasionally run in duplicate. In these cases it was found that there was good reproducibility between the test kits over a range of levels from 1.1 to 14.5 pCi/L, with the average difference being under 10%.