Environmental Factors Influencing Temporal Indoor Radon Concentration
M.S. Jawad; D.K. Worthy; L.R. Baumgarten; J.A. Moore; and K.J. Kearfott (University of Michigan)
Some early work has attempted to link indoor and outdoor atmospheric pressure to indoor radon concentration. Other prior work has considered the connection between indoor and outdoor temperature differences, or wind speed and wind direction, and radon, but any observed correlations were found to stem from indoor and outdoor pressure differences. A comprehensive statistical evaluation of all possible environmental factors which could influence indoor radon concentration is the subject of this research. Research is being conducted to measure indoor radon concentrations and observe any correlations with atmospheric conditions. The indoor radon concentration is being measured using a continuous radon monitor that tabulates hourly averages in a first floor laboratory of a two-story building with a basement. Hourly indoor pressure, temperature, and humidity data are being collected by a monitor located inside the laboratory near a continuous radon detector. Hourly outdoor pressure, temperature, humidity, wind speed, wind direction, and precipitation data are being collected from a weather station located on the roof of the building. Snow cover is periodically measured as appropriate. All variables are measured simultaneously in order to observe any cross correlations between variables or combinations of them with radon concentration. These results can be used by radon testers to determine when radon concentrations will be at their maximums or to help interpret data obtained under given conditions. A preliminary analysis of a portion of the results has shown that outdoor pressure, indoor temperature, outdoor temperature, and indoor humidity show some significance in the effects on radon concentration. Initial statistical analysis has shown that indoor pressure, wind direction, and wind speed have are of no significance.