Detection of Radon, Radon Daughters and Thoron Daughters in Abu Tartur Open Pit Phosphate Mine, Egypt

In this study, Abu Tartur open-pit Phosphate mine and underground tunnels have been studied from radiation safety point of view. Radon, radon daughters and thoron daughters were measured by collecting (31) samples from (5) main sites that represent the process of Phosphate mining. Results of radon, radon daughters and thoron daughters, in case of open-pit mining ranged from 1.37 to 131.52 Bq m-3, 0.000099 to 0.0024 WL, and 0 to 0.92 Bq.m-3 respectively. For postpone tunnels, results of radon, radon daughters, thoron daughters ranged from 411.55 to 2539.27 Bq m-3, 0.056 to 0.37 WL, and 1.26 to 3.89 Bq.m-3 respectively. Also, gamma radiation levels, surface contamination and effective annual dose were measured. Gamma radiation levels ranged from 0.07 to 0.6 mSv/h for openpit mine and from 0.24 to 0.5 mSv/h for tunnels. Surface contamination measurements gave normal readings for open-pit mining and 7.1 in underground mine. The effective annual dose ranged from 0.033 to 0.153 mSv/y for open-pit and 4.948 mSv/y for tunnels. The results, in case of open-pit mine, are lower than permissible limits determined by UNSCEAR, 2010 while exceeds the permissible limits in case of underground tunnels. So the open-pit mining is much safer from the occupational radiation protection point of view.