Measurement and Analysis of Indoor Radon Concentrations in Selected Residential Buildings in Jos, Plateau State

Background: Indoor radon exposure is a recognised radiological health hazard linked to lung cancer risk. Geological formations rich in uranium and thorium in North Central Nigeria's Jos Plateau may elevate radon emanation in residential buildings. Aim: This study measured and analysed indoor radon concentrations in selected residential buildings in Jos, Plateau State. Methods: CR-39 solid-state nuclear track detectors were deployed in 45 rooms across 15 residential buildings in three Jos neighbourhoods over a 90-day exposure period. Track density was determined using a calibrated optical microscope, and radon concentrations were calculated from track density calibration factors. Results: Radon concentrations ranged from 18 to 145 Bq/m3, with a geometric mean of 62 Bq/m3. Seven rooms exceeded the WHO reference level of 100 Bq/m3. Buildings with poor ventilation and granite-based foundations recorded the highest concentrations. Annual effective dose estimates ranged from 0.46 to 3.68 mSv. Conclusion: Indoor radon levels in Jos pose a moderate radiological concern in poorly ventilated buildings. Improved ventilation practices and building material selection guidelines are recommended for new construction in radon-prone geological zones. Keywords: radon, CR-39 detectors, indoor radiation, Jos, health hazard.