Assessment of radon and carrier gases in an underground gold mining company in Ghana.

Previous studies in Ghanaian mines have largely focused on radon concentration and associated health risk, with limited investigation into the role of carrier gases that influence radon transport from bedrock. This study evaluates radon (222Rn) levels, carrier gases (CO2, H2S, CH4), and their associated health risks in an underground section of the AngloGold Ashanti mine. Measurements were conducted in two phases using CR-39 solid-state nuclear track detectors and a Ventis Pro5 multi-gas detector. The average radon concentration across both phases was 214 ± 16 Bq·m-3, with phase-specific means of 245 ± 8 Bq·m-3 and 184 ± 6 Bq·m-3. Based on ICRP 137, the annual effective dose and excess lifetime cancer risk were estimated at 0.6 ± 0.2 mSv y-1 and 1.5 × 10-3 per million persons/year, respectively, both below ICRP and NCRP safety limits. Concentrations of all carrier gases remained within OSHA and Chart Industries recommended exposure limits. Principal component analysis indicated that methane and hydrogen sulfide significantly influence radon distribution with Eigenvalue >1, Overall, the findings suggest that the current levels of radon and carrier gases in the mine do not pose significant health risks to underground workers.