Occupational radiation risk caused by NORM in coal mining industry

The radiation risk due to the exposure to natural radionuclides, especially to short-lived radon progeny, is a component of the radiation hazard, common in the natural environment and working environment. In Polish mining industry the radiation hazard, caused by natural radionuclides is the natural hazard. Radon in air and radium present in underground brines are sources of radiation hazards. Sediments precipitated out from such waters with enhanced radium content may cause the increase of external gamma radiation dose rate as well as internal contamination due to accidental ingestion or inhalation. Investigation of that specific problem has been started in hard coal underground mines in Poland in early 1970’s. At the end of 1980’s first regulation was issued. Dose limits and requirements of the radiation monitoring have been established, internal regulations for monitoring and mitigation measures were developed on the basis of the Polish standard. The monitoring and prevention against natural radiation is obligatory in all Polish underground mines since 1989. This duty is strictly supervised by local offices of State Mining Authority in co-operation with other governmental agencies.