We aimed to provide a systematic evaluation of magnetic field (MF) exposure of staff working in the offices located above or close to transformer stations (TS) and electric enclosures (EE). Occupational short-term ""spot"" measurements with Narda EFA-300 and isotropic magnetic field probe were carried out in two National Banks and one Industrial Company having more than 500 employees. Extremely low-frequency (ELF) MFs up to several tens of mu mu T were measured in the mentioned working environments. 25% of the measured MFs were found less than 0.3 mu mu T, the background exposure level that staff receive at home, 75% were above 0.3 mu mu T with the highest value of 6.8 mu mu T. The mean and median personal exposures were calculated to be 1.19 mu mu T and 0.56 mu mu T, respectively. Most of the staff (83%) is under risk based on epidemiological studies that reported a statistically significant association between risk of leukemia and averaged magnetic fields of 0.2 mu mu T or over. Results showed that risk evaluation should be considered to minimize the possibility of the workers being harmed due to exposure to work-related electromagnetic sources.