## 3 Results  
### Field Measurements  
The measurements of the equivalent noise levels conducted before and after the reconstruction of intersections into roundabouts in Michalovce city are shown in Table 7 and Figure 6.  
Before rehabilitation, the reconstructed intersections (R1, R2, and R3) in Michalovce had a good quality wearing surface course without repairs, dents, or cracks. The conducted noise pollution measurements found that the implementation of roundabouts R1 and R2 reduced the noise level by an average of 2.2 dB. One to three-octave noise analyses were not available for R3, and hourly measurements of equivalent noise levels found a reduction of 2.8 dB. This high value compared to those of R1 and R2 was caused by the poor-quality road surface of the intersection pavements before their reconstruction into a roundabout. Additionally, according to statements of local citizens living near R3, there was a significant reduction in noise pollution in the vicinity of the roundabout. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multicolumn{5}{c}{**Equivalent Noise Level from Road Traffic [dB] at the Intersection before and after Reconstruction to R1**} \\ \hline
**Before** & \(\mathbf{L_{Aeq,15\,\text{min}}}\) & **After** & \(\mathbf{L_{Aeq,15\,\text{min}}}\) & \\ \hline
29 May 2006 & 59.5 & 61.1 & 12 March 2007 & 58.6 & 58.7 \\ \(11^{\text{10}}\) to \(12^{\text{20}}\) & 61.1 & 59.8 & \(10^{\text{30}}\) to \(11^{\text{15}}\) & 58.3 & - \\ \hline \multicolumn{5}{c}{**29.5.2006 \(\mathbf{L_{Aeq,1\,\text{h}}}\) = 60.4 dB and 12.3.2007 \(\mathbf{L_{Aeq,45\,\text{min}}}\) = 58.5 dB**} \\ \hline \multicolumn{5}{c}{**Equivalent Noise Level from Road Traffic [dB] at the Intersection before and after Reconstruction to R2**} \\ \hline
29 May 2006 & 63.7 & 60.0 & 12 March 2007 & 58.9 & 58.5 \\ \(12^{\text{30}}\) to \(13^{\text{30}}\) & 60.0 & 61.0 & \(12^{\text{200}}\) to \(13^{\text{30}}\) & 59.5 & - \\ \hline \multicolumn{5}{c}{**29.5.2006 \(\mathbf{L_{Aeq,1\,\text{h}}}\) = 61.5 dB and 12.3.2007 \(\mathbf{L_{Aeq,45\,\text{min}}}\) = 59.0 dB**} \\ \hline \multicolumn{5}{c}{**Equivalent Noise Level from Road Traffic [dB] at the Intersection before and after Reconstruction to R3**} \\ \hline
12 March 2007 & 56.6 & 57.4 & 29 April 2008 & 55.3 & 55.0 \\ \(12^{\text{200}}\) to \(13^{\text{30}}\) & 58.3 & 57.9 & \(10^{\text{30}}\) to \(11^{\text{15}}\) & 54.5 & 54.4 \\ \hline \multicolumn{5}{c}{**12.3.2007 \(\mathbf{L_{Aeq,1\,\text{h}}}\) = 57.6 dB and 29.4.2008 \(\mathbf{L_{Aeq,45\,\text{min}}}\) = 54.8 dB**} \\ \hline \hline \end{tabular}
\end{table} 
Table 7: \(L_{Aeq}\) from traffic at the intersection of R1, R2 and R3 before and after the reconstruction. Figure 5: Wind rose values for the prevailing winds at the three-arm intersection (**left**) and roundabout (**right**). Measurements of the noise load in the city of Zilina revealed a decrease in noise levels after the reconstruction of the three-arm intersection into a roundabout. Reductions in the noise level were by 3.4 dB at monitoring station MS1 and 2.9 dB at MS2. Measurements after five years of use of the roundabout revealed a slight increase in the noise load in the vicinity of the intersection. Compared to the original three-arm intersection, the decreases were 2.6 dB at MS1 and 2.1 dB at MS2 (Table 8, Figure 7).