Control of Radiation Hazards in Underground Uranium Mines.
Chap 69 in "Radiation Hazards in Mining: Control Measurement and Med Aspects" PP 441-446 :441-446
Alpha-emitting radon daughter products are a recognized health hazard contributing to the development of lung cancer in persons exposed to excessive concentrations over an extended period. The primary control technique used by the mining industry is dilution with fresh air. Because the uranium is deposited in porous sandstone in most U.S. mines, the control of this hazard with dilution requires excessive volumes of air. As the mines become larger and deeper, the cost for ventilation becomes a major expenditure for the mining industry. Most mines are maintaining levels of radon daughters lower than required by law but to maintain these present levels the mining companies are going to be drilling more vent holes or using other control techniques as the mine expands. These control techniques are being investigated by the Bureau of Mines to determine their effectiveness, cost, and safety for underground use.
Chap. 69 in "Radiation Hazards in Mining: Control, Measurement, and Med. Aspects", PP. 441-446