Indoor radon survey in a university campus of Nigeria

CR-39 tracketch detectors were used for the measurement of 222 Rn concentration in 24 offices in Nigeria′s oldest university campus in order to estimate the effective dose to the occupants from 222 Rn and its progeny. The dosimetric measurements were made over a period of 3 months. Questionnaires were distributed and analyzed. The radon concentration ranged from 157 to 495 Bq /m 3 , with an arithmetic mean and standard deviation of 293.3 and 79.6 Bq/ m 3 , respectively. The effective dose to the workers was estimated and this varied from 0.99 to 3.12 mSv/ y, with a mean of 1.85 mSv /y. The radon concentrations were found to be within the reference levels of ICRP.