## 3 Results and Discussion  
The effect of air flow speed on the thermal comfort of people in the operating room was monitored during the measurement. The effect of different volumetric flow rates and velocity profiles of air flow on the thermal comfort in the OR was investigated. The higher the speed in the person's residence zone, the higher the feeling of cold. This can create negative feelings for the staff in the operating room and thus degrade the working conditions and the overall performance of the staff. The measurements in the experimental laboratory were made at different speeds of air flow from the laminar field. The recommended outflow velocity of the laminar field is in the range of 0.15-0.25 m/s for most manufacturers. With the known air speed from the laminar field and the known free outlet area (in our case, 3.55 m\({}^{2}\)), we can determine the amount of air transported by the distribution element using Equation (2). The amount of air transported at different speeds as well as the designation of variants for these conditions is expressed in Table 3. According to the amount of transported air, five different variants were measured, from a speed of 0.15 m/s to a speed of 0.25 m/s, with graduations of 0.025 m/s. A 10% smaller amount of air is removed from the space, evenly distributed between the four corners of the room through exhaust diffusers of 0.5 \(\times\) 0.2 m.  
\[V_{SUP}^{\cdot}=v_{SUP}\cdot S_{SUP} \tag{2}\]  
\(V_{SUP}^{\cdot}\)--air flow of the supply distribution element (m\({}^{3}\)/h)  
\(v_{SUP}^{\cdot}\)--speed of the air flowing from the supply distribution element (m/s)  
\(S_{SUP}\)--free outlet surface of the supply distribution element (m\({}^{2}\))  
The parameters determining thermal comfort in the environment are listed in Table 4. At three height levels (0.1, 1.1 and 1.7 m from the floor level), the air temperature and air flow velocity in the room were measured using the \"draft probes\" shown in Figure 7c. The probe for measuring humidity is shown in Figure 7d, and the probe for measuring the mean radiation temperature, or the operating temperature expressed from it, is shown in Figure 7e. The vertical position of the individual measuring members (Y) is determined by the recommendation for measuring thermal comfort and local discomfort (warm head, cold ankle, etc. ). \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Measuring Element**} & \multirow{2}{*}{**Unit**} & \multicolumn{5}{c}{**Variant**} \\ \cline{3-6}  & & **1** & **2** & **3** & **4** & **5** \\ \hline H1 & t\({}_{\text{a}}\) (\({}^{\circ}\)C) & 23.1 & 22.6 & 23.5 & 23.7 & 23.0 \\ H2 & t\({}_{\text{a}}\) (\({}^{\circ}\)C) & 23.4 & 23.5 & 23.7 & 24.3 & 22.5 \\ H3 & t\({}_{\text{a}}\) (\({}^{\circ}\)C) & 23.8 & 24.1 & 23.8 & 24.8 & 22.7 \\ H1 & v\({}_{\text{a}}\) (m/s) & 0.10 & 0.14 & 0.05 & 0.11 & 0.09 \\ H2 & v\({}_{\text{a}}\) (m/s) & 0.12 & 0.15 & 0.20 & 0.24 & 0.25 \\ H3 & v\({}_{\text{a}}\) (m/s) & 0.03 & 0.05 & 0.19 & 0.19 & 0.20 \\ OT & t\({}_{\text{o}}\) (\({}^{\circ}\)C) & 23.4 & 23.4 & 23.5 & 24.1 & 22.6 \\ RH & \(\varphi\) (\%) & 44 & 44 & 42 & 40 & 45 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Parameters of thermal-humidity microclimate for individual variants. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Variant** & \(\mathbf{v_{SUP}}\) **(m/s)** & \(\mathbf{V_{SUP}}\) **(m\({}^{3}\)/h)** \\ \hline
1 & 0.150 & 1916 \\
2 & 0.175 & 2235 \\
3 & 0.200 & 2555 \\
4 & 0.225 & 2874 \\
5 & 0.250 & 3194 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Air flow of the laminar field for individual variants. Figures 9 and 10 show the temperature and air velocity profiles on the imaging planes passing through the center of the LAFC (reference point (x,y,z) = (0,0,0)), lower left corner of Figure 8). Lower outflow velocities through the LAFC cause the formation of higher temperature gradients in the vertical direction, and stratification of air with a different temperature occurs.