Abstract Research was conducted to measure indoor radon concentrations and observe any correlations with indoor and outdooratmospheric conditions for over a period of one year. The indoor conditions were measured both in a first floor laboratory with goodventilation and in a basement with poor ventilation of a two-story building. Radon concentrations were collected using identicalcontinuous radon monitors that collect hourly averages of the radon concentration. Indoor pressure, temperature, and humidity datawere also collected on an hourly basis. Hourly outdoor pressure, temperature, Dew point, wind speed, and wind direction data wereobtained from a monitoring system on the roof. The monthly average indoor radon concentration values in Lab vary from 13.6 Bqm-3 to 51.2 Bq m-3 with an average value of 28.0 Bq m-3, which is less than the action level (200-300 Bq m-3) recommended by ICRP.The seasonal correction factors in lab range from 0.55 to 2.06, while the seasonal correction factors in Basement range from 0.98 to1.01 with no much variation. The results indicate that the indoor radon concentration is higher in autumn season than in winter andsummer season. Correction analysis showed that the variables found to be significant determinants of radon concentration were thedifference between indoor and outdoor temperature, indoor and outdoor pressure. Indoor radon concentrations are negativecorrection with indoor humidity, outdoor temperature and Dew point temperature. Wind direction, wind speed, and indoor pressurehad no significance on indoor radon concentration variation.