Assessment of indoor and outdoor Ambient Radiation Level at Beuchi Road Campus of University of Jos in Some selected Lecture Halls and Laboratories

This study assessed ambient ionizing radiation levels at the University of Jos Bauchi Road Campus, Nigeria, focusing on indoor and outdoor settings across 42 lecture halls, 34 laboratories, 25 faculties, and 7 outdoor arenas. Using a calibrated GQ GMC-600 Geiger-Müller counter, indoor dose rates ranged from 0.15–0.49 µSv/hr (mean IAEDR: 2.18–2.48 mSv/yr), while outdoor rates spanned 0.09–0.46 µSv/hr (mean OAEDR: 0.54–2.09 mSv/yr). Indoor doses, driven by radon retention from granite-rich materials and poor ventilation, exceeded the ICRP public limit of 1 mSv/yr, with high-risk areas like Biochemistry (2.99 mSv/yr) and Physics Library (3.41 mSv/yr). Outdoor doses, influenced by Jos' uranium-thorium-rich geology, peaked at the Department of Human Physiology (3.17 mSv/yr). Excess Lifetime Cancer Risk (ELCR) averaged 0.61–0.69 × 10⁻³ indoors and 0.15–0.58 × 10⁻³ outdoors, surpassing the acceptable range (0.01–0.1 × 10⁻³), indicating elevated long-term cancer risks. Mitigation includes enhanced ventilation, low-radioactivity materials, and real-time dosimetry in high-risk zones. Continuous monitoring and adherence to ALARA principles are recommended to align with international standards, addressing health risks in this geologically unique academic environment.