## 2 Materials and Methods  
In a home environment, there are low-frequency electromagnetic wave emitters originating from the mains voltage used by lighting and electronic devices and high-frequency (broadband) electromagnetic wave emitters such as mobile phones and wireless modems. Figure 1 shows the four environments (bedroom, living room, entrance, and kitchen) in which measurements were made and the list of low- and high-frequency electromagnetic emitters in these four environments. The height of the measured floor from the ground is 15 m. Both the interior and exterior walls of the floor consist of 13 cm of bricks and 1 cm of concrete on top of the bricks. Figure 2 shows the building, floor, wireless modem, devices where the measurement was made, and location and coordinate information via Google Earth. There are institutions and organizations that determine the impact of both low- and high-frequency electromagnetic waves on human health, both the electric field and the  
Figure 1: Measurement environments and electronic devices in the environment. Figure 2: Measurement place and measuring instruments. limits of the SAR values created by these electric fields, especially on the human head, both nationally and internationally, depending on the frequency. While there may be countries that apply these international limit values as they are, there are countries that accept and implement values smaller than these values. While ICNIRP is the international organization that determines these limit values, the Information Technologies and Communications Authority (ICTA) determines them in Turkey. ICTA uses 70% of the value determined by ICNIRP [28]. Figure 3 shows the variation of ICNIRP and ICTA's general public exposure electric field limit values with frequency. In this study, low and broadband electric field effective values were measured in a house in four different environments for 24 h. 50 Hz source measurements were made with the NF-3035 measuring device (Gewerbegebiet Aaronia AG II, DE-54597 Strickscheid, Germany) (0-1 MHz), and broadband measurements were made with the HF-60105 device and the Omnilog 90200 antenna (Germany) (700 MHz-2500 MHz) connected to it. 1000 electric field effective values were recorded in every environment for 24 h.  
Broadband is divided into 15 sub-bands, and the low and high-frequency values of each sub-band and the middle-frequency (\(f_{r}\)) of each sub-band are shown in Table 1. It can be seen from the table that broadband electric field measurement values are distributed only in six sub-bands (LTE 800, ETC 1, GSM 900, ETC 2, LTE 1800, and WLAN), and the other nine sub-bands are empty. \[f_{r}=f_{lower}+\frac{f_{upper}-f_{lower}}{2} \tag{1}\]  
By looking at the normalized root mean square error (NRMSE) values of all fitted curves, the curve with the smallest NRMSE value (\(0<R\)-_squared_\(\leq 1\)) was selected as the most suitable curve to determine whether the curves fitted to the density and cumulative probability (CP) values of the measured electric field effective values were the most suitable. \[NRMSE=\frac{\sqrt{\frac{1}{N}\sum_{i=1}^{N}(x_{i}-\hat{x}_{i})^{2}}}{max(x)-min( x)} \tag{2}\]  
Figure 3: Electric field limit values determined by ICNIRP and ICTA for humans [29]. where \(N\) is the total number of measurements, \(i\) is the sample taken, \(x_{i}\) is the measured electric field value, and \(\delta_{i}\) is the electric field value of the fitted curve. In order to calculate the SAR values caused by broadband measurement values on the head and brain of people living in the measurement environments, the density values and density values of the six-layer human head model created using the middle frequencies (\(f_{r}\)) of the six sub-bands are shown in Table 2.  
To calculate the SAR values of relative permittivity and electrical conductivity (S/m) (\(\varepsilon_{r},\sigma\)) in Table 2, the six-layer head model, which is given for each layer and density values (\(\varepsilon_{r},\sigma\)) and created by taking these into account, is shown in Figure 4.