The U.S. Environmental Protection Agency's Office of Radiation Programs is conducting a multifaceted study of the radiological implications of the phosphate mining and milling industry in the United States. The study began in June 1974 and has concentrated mainly on facilities located in Florida, North Carolina, and Idaho. The purpose of this study is to evaluate the radiological impact of this industry on the environment and develop appropriate radiation protection guidelines in areas where existing controls are determined to be inadequate. A study was conducted in a house in Polk County, Florida, to determine the effects of normal home ventilation methods on radon, radon progeny, and working levels. Three ventilation conditions were studied which approximate those found during normal occupancy. The effects of the central air conditioner, the central blower without air conditioning and outside air ventilation were studied, with radon, radon progeny, and working level measurements made sequentially until significant changes ceased to be observed. In all three experiments, radon, radon progeny, and working levels decreased, with the decreases corresponding to estimated increases in house ventilation rate.

Final report. Performing Organization: Eastern Environmental Radiation Facility. Includes bibliographical references (page 19). "EPA-520/5-77-011."