A comprehensive review of radon concentrations and annual effective dose amongst workers in copper mines

Radon, a carcinogen for lung cancer is chemically inert, colourless, odourless, and a radioactive gas that originates from uranium and thorium radioelements. This review article presents radon concentrations and annual effective dose (Ey) amongst workers in copper mines, as well as examining factors influencing radon levels. Findings indicate varying radon concentration levels ranging from acceptable values to those exceeding the occupational exposure limit of 1000 Bq.m-3. For instance, mean radon concentrations ranged from 6.6 Bq.m-3 to 2400 Bq.m-3 under mechanical ventilation, increasing by a factor of eight under nonmechanical ventilation. Similarly, Ey values ranged from 0.80 mSv.y-1 to above the 20 mSv.y-1 threshold, reaching as high as 34 mSv.y-1. Ventilation emerged as the prominent factor influencing radon concentration, alongside temperature, seasonal changes, and mining activities. The study recommends adequate ventilation and routine radon monitoring to improve air quality and protect workers.