Exposure assessment of radio frequency electromagnetic field levels in hospitals of Samsun Province, Turkey

With the increase in the use of different types of electronic systems used inside and outside the hospital, the electromagnetic medium in the hospital has changed significantly. The increase in the number and type of EMF sources in sensitive mediums such as hospitals has led researchers to measure EMFs to assess the potential risk to patients and staff. For this reason, this study aims to determine the radio frequency electromagnetic field (RF-EMF) levels to which patients and staff are exposed voluntarily or unintentionally in the hospital environment and to control their compliance with the limits defined in the standards. In order to achieve these goals, three different types of RF-EMF measurements were carried out as, short-term, long-term, and band selective in 21 state hospitals in the Samsun Province, Turkey. Total RF-EMF in the band between 100 kHz and 3 GHz is measured using PMM–8053, while band selective is conducted using SRM–3006 in the frequency range from 27 MHz up to 3 GHz. The recorded RF-EMF values were statistically analyzed, and the main RF-EMF sources in the medium were determined. The highest average RF-EMF exposure level obtained for short-term measurements was 2.52 V/m. For long-term measurements, the highest average RF-EMF was 3.11 V/m and the highest mean RF-EMF was 2.29 V/m. Within our measurements, the limit of 3 V/m set by the Information and Communication Technologies Authority (ICTA) was exceeded in the hospital, although the highest RF-EMF was below the limit level set by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). Long-term measurement results showed that the RF-EMF level at midday was higher than at night; the highest RF-EMF was measured in the afternoon and during evening hours. The mean RF-EMF levels are 1.01 V/m, 1.15 V/m, 1.12 V/m, and 0.84 V/m, for morning, afternoon, evening, and night respectively. The RF-EMF level measured during the afternoon hours maybe about 37% higher than the RF-EMF levels measured at night. The main sources of total RF-EMF in the environment determined from the band-selective RF-EMF results were base stations located outside the hospital and their contribution to total RF-EMF was 92.6%. Systems that make the most contribution to the RF-EMF in the environment are base stations using the LTE 800, GSM 900, GSM 1800, LTE 1800, and UMTS 2100 frequency bands. Among these, the UMTS 2100 frequency band gave the highest contribution with 40.42%. With the use of these main RF-EMF sources, an empirical model that helps in computing the total E of the medium with 99.8% accuracy was proposed.