The present paper aims to assess the level of exposure to ambient electromagnetic field, generated especially by mobile phone stations. In a first phase, before the implementation of 5G (fifth generation), the power density was measured in the vicinity of 1750 base stations of Orange Romania SA, distributed throughout the country, and was reported at the lowest reference value provided of the national legislation for the general public in the case of the mobile telephony systems in which Orange Romania’s stations operate. The maximum exposure coefficient was thus obtained as a percentage value from the limits provided in ICNIRP (International Committee on Non-Ionizing Radiation Protection). In phase 2, after the development of the 5G network in Bucharest, 122 sites were remeasured, again calculating the maximum exposure coefficient as a percentage value. The results showed that regardless of the environment, over 90% of the measurements are below 0.2% of the limits provided by ICNIRP and 99% of the measurements are below 2% of the limits provided by ICNIRP.