[Discrepancies in assessment of radiological exposure level in miners related to the use of various measurement systems].

The contamination of the air with radioactive elements (radon-222 and its decay products) occurs in coal, metal ore and chemical raw materials underground mines. This causes irradiation of the miner's respiratory system with ionizing radiation. In Poland the radiation exposure level is controlled both by the ventilation services of particular mines and by the Nofer Institute of Occupational Medicine in Lodz to the order of the State Sanitary Inspection. The in-mine services collect air samples which are next examined to determine the degree of radiation contamination (environmental monitoring), whereas the Institute uses the method of representative individual dosimetry (the dosimeters are attached to the miners' helmets). The article presents discrepancies in the levels of exposure to radiation in mines, assessed by the in-mine services and the Nofer Institute of Occupational Medicine. The hazard level determined by these services is usually one or even two times lower than that determined by the Institute. The reasons for these discrepancies are discussed.