Assessment of Leakage and Scattered Radiation in Selected Computed Tomography Facilities over Jos, Plateau State, Nigeria

Abstract

This study assessed leakage and scattered radiation levels in three computed tomography (CT) facilities in Jos, Plateau State, Nigeria, as part of routine quality assurance and radiation safety evaluation. A calibrated GMC-600 digital Geiger Muller counter was employed to measure radiation levels, ensuring traceability to national calibration standards. The detector was positioned at 1 m from the gantry in four different directions (front, back, left, right) to determine leakage radiation, and at the console area to quantify scattered radiation during phantom exposures. The mean leakage radiation values recorded were 6.94, 5.93, and 8.97 mR/hr for facilities X1, X2, and X3, respectively. Mean scattered radiation levels at the console areas were 3.62, 2.14, and 2.94 mR/week. All results were well below the American Association of Physicists in Medicine (AAPM) recommended limits of 100 mR/hr for leakage and 10 mR/week for scatter, indicating full compliance with international safety standards. Statistical analysis revealed significant variation in leakage radiation between facilities (p < 0.05), with older equipment demonstrating higher leakage values. These findings suggest that equipment age and shielding design may influence radiation safety performance. Although compliance was achieved across all facilities, the study emphasizes the importance of periodic monitoring, preferably on an annual basis, to ensure sustained adherence to safety standards. Furthermore, integrating occupational dose monitoring and image quality assessments into routine quality control programs will strengthen radiation protection practices, optimize patient safety, and safeguard radiology personnel in resource-limited settings.