A study on natural radioactivity in Khewra Salt Mines ...
The Khewra Salt Mines, the second largest salt mines in the world, are located 160 km south of Islamabad, the capital of Pakistan. Around 1000 workers are involved in the removal of salt from these mines. More than 40,000 visitors come annually to see the mines. The visitors and workers are directly exposed to the internal and external radiological hazards of radon and gamma rays in these mines.