This paper deals with the measurement of electromagnetic field parameters near high voltage systems, characteristics of electric field, magnetic field and electromagnetic field, as well as the possibilities of implementing measures to reduce the emitted electromagnetic field. The paper describes the measurement of electromagnetic field parameters in the vicinity of high voltage systems, the analysis and synthesis of the measurement results in the external and internal environment of particular transformer stations is evaluated. The objects of interest in these measurements were brick transformer stations for transforming AC voltage from 22 kV to 400 V and 230 V at the operating frequency of 50 Hz. With regard to the influence of electromagnetic fields in the environment, individual measurements were assessed in accordance with selected criteria.