Radon gas measurement in deep gold mines
Measurements of radon gas concentration in the two western region gold mines in Ghana have been carried out. The measurements were made from the alpha-track density on CR-39 solid state nuclear track detector, using the closed can technique during 1992 and 1993. Average values of 37.5Bqm-3 and 48.6Bqm-3 were recorded in the offices for Tarkwa and Prestea Goldfields respectively. There were large variations in the underground results which range from 56.4Bqm-3 to 268.3Bqma-3 for Tarkwa Goldfieids and from 42.6Bqm-3 to 877.7Bqm-3 for Prestea Goldfields. These were observed to be caused by the different rock formation and the ventilation at the sites of the measurements. Radon exposure units in Working Level (WL) and the Working Level Month (WLM) were also calculated for the mines. These results show that the radon concentrations at, the offices at Tarkwa and Prestea are below the maximum safe of 110Bqm-3 as recommended by National Radiological Protection Board, (NRPB) UK. However, sixteen (16) out of the twenty five (25) underground locations monitored in the two gold mines have radon concentrations above the recommended limit.
A thesis submitted to the Board of Postgraduate Studies, Kwame Nkrumah University of Science and Technology, Kumasi, in partial fulfilment of the requirement for the award of the Degree of Master of Science in Physics, 1994