Assessment of Radiation Dose Rates at the Faculty of Engineering, Ahmadu Bello University, Zaria

Abstract

This study assessed ambient radiation dose rates at the Faculty of Engineering, Ahmadu Bello University (ABU), Zaria, Nigeria, to evaluate potential health risks and compliance with international safety standards. Using a portable gamma spectrometer and GPS device, in-situ measurements of gamma radiation were taken at 20 locations across the faculty. The mean absorbed dose rate was 123.97 nGy/h, exceeding the global average of 59 nGy/h (UNSCEAR, 2000). The highest dose rate (166.63 nGy/h) was recorded at Latitude 11.1541°N, Longitude 7.6249°E, indicating localized radiation hotspots. The calculated Annual Effective Dose Equivalent (AEDE) ranged from 0.100 to 0.204 μSv/year, while the Excess Lifetime Cancer Risk (ELCR) reached 1.67 × 10⁻⁷ at the most elevated site—still below the ICRP (2007) threshold of 2.9 × 10⁻⁴. Spatial analysis revealed variability linked to geological composition and anthropogenic factors. The findings contribute to baseline radiological data for ABU Zaria and underscore the need for routine monitoring to ensure occupational and environmental safety.