There is a significant increase in the use of mobile communications services and it is expected that this growth will continue with the introduction of new generations of technology standards such as Long Term Evolution (LTE), for example. The exposure from environmental sources in urban areas is formed mainly by broadcasting antennas, and base stations for mobile communications. The large number of telecommunication sources placed in the urban areas provoked serious concerns about possible health effects, considering the exposure to electromagnetic fields (EMF). Particular attention has been paid to the so-called “critical” or “sensitive” areas around hospitals, schools, kindergartens, etc. Hence, there is a need of adequate exposure assessment of the electromagnetic field levels in some selected high populated urban areas especially around hospitals, schools, kindergartens to ensure that the power density levels are well below the prescribed threshold limits. The report presents an exposure assessment of electromagnetic field emitted by telecommunication sources (base stations) which has been performed at selected “sensitive” areas around hospitals, schools, kindergartens, located throughout Sofia. The study is conducted under the BG07 Program: Public Health Initiatives with the financial support of the Norwegian Financial Mechanism 2009-2014 and the European Economic Area Mechanism, 2009-2014, entitled “Improving control and information systems in risk prevention and healthcare”. Different methods of exposure assessments have been used: in-situ measurements (outdoor spot measurements of electromagnetic field values) using non- frequency selective and frequency selective measurement methods, as well as a broadband EMF monitoring for continuous measurement of the total EMF from all surrounding telecommunication sources that were also provided. The analyses of the measurement results suggest that the exposure levels to RF-EMFs are generally well below the reference levels defined by the national and European legislation. The electromagnetic field levels at the most studied locations are lower (up to 50%) than the limit values according to the Bulgarian legislation and less than 1% of the limit values according to the European legislation for the frequency band about 900 MHz.

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