A recent epidemiological study, conducted by Dr. Donald Nelson and his colleagues at Worcester Polytechnic Institute suggested that the risk of radon at exposures less than 4.0 pCi/L may not agree with the assumption of a linear-no-threshold model. In fact, their data suggests there may be a beneficial effect in reducing radon related lung cancer risk at exposures less than 4.0 pCi/L. Their findings have sparked a lot of discussion in the radon industry about the impact of this study. Listen in on an interview with Dr. Nelson regarding his team's methodology and how these results may be used in increasing our understanding of the health effects of radon.