The Health Safety Programme for Workers Exposed to Elemental Mercury at the Mercury Mine in Idrija

In the Idrija Mine ore appears in two forms: the first as cinnabar (70%) and the second as native mercury (30%). In the area where native mercury was mined the concentrations of elemental mercury in the working and unventilated areas of the pit were very high, they periodically reached over and above 3 mg/m³ of air and most of the time exceeded the maximum acceptable levels of mercury vapours in the air (0.1 mg/m³). In such specific working conditions the number of workers suffering from the effects of mercury was very high. Work conditions in the mine urgently required more effective and preventative measures against exposure to mercury. The health and safety program includes monitoring of mercury concentrations, technical measures, personal protection, evaluation of individual external intensity of exposure and medical surveillance. The results were very successful, the number of mercun intoxicated workers dropped and after 1975 there were no more intoxicated workers, in spite of the increase in the number of areas worked where native mercury was present.