The author presents an account on application of results of imission monitoring of the atmosphere implemented by the hygiene service for calculation and estimates of health risk caused by inhalation of air contamined with nitrogen oxides Sulphur dioxide and ozone using the method "Health Risk Assessment" according to U.S.EPA. The results of the imission monitoring of the atmosphere are processed retrospectively for a five-year period (1997 - 2001) and the health risk are related to a hypothetical 1-year exposure from the aspect of non-carcinogenic effect of different pollutants by a Hazard Index = HI. The author presents a brief review of methodical steps incl. identification of the noxious substances, assessment of their noxious character, conditions of exposure. Within the framework of characterization of the risk the mean 5-year exposure concentrations of different pollutants are related to quideline values of classifical pollutants in the free atmosphere according to WHO (GV WHO) (7) which thus replace the reference concentrations.

        Key words: imission monitoring of air - quideline value - health risk assessment - identification of pollutants - hazard identification