## 4 Discussion  
A sufficient water route is required for a vessel's safe navigation. While a ship is sailing, there is a regulation that requires an appropriate route width for emergencies or collision avoidance. The harbor and fishery design criteria are used to create the route in Korea. Here, the standard for the width of the route is 0.5-2.0 length overall (L), and restrictions are depending on the length of the passing vessel [43]. Furthermore, the World Association for Waterborne Transport Infrastructure (PIANC) is a global route design guideline centered on Europe [44]. The interaction of OWFs and maritime navigation of PIANC working group 161 is focused on resolving MSP disputes. In particular, it deals with the conflict between the OWF and ship navigation. In PIANC working group 161, the space required for the Starboard side wind farm and shipping route is 0.3 Nautical Mile + 6 Ship lengths + 500 m, while the space required for the Port side wind farm and shipping route is 6 Ship lengths + 500 m. According to the data, the largest sailing vessel is 399 m, which is calculated as 3.5 km and 2.9 km by the Starboard side and Portside, respectively, and it is calculated to have 6.4 km of free water on both sides.  
As a result of the ship's steering characteristics, there is a difference in the safety distance between the Starboard and Port sides, as shown in Figure 10. The value chosen for both sides is 6.4 km, which is compared to the width of the main route calculated in this study. It can be seen that the place where the width is smaller than the value of PIANC does not have an appropriate distance with OWFs, and the location that is greater than the  
Figure 9: Result of the Korean maritime traffic main route as polygon creation.  
PIANC value appears to have an appropriate distance. Figure 11 is a graph that extracts the route width of the main route for each vertex point.  
It was stated that the outer branch route can be moved and changed through appropriate regulations, whereas the inner branch route has limitations in applying PIANC regulations because many places pass through very narrow sea areas. Therefore, in any case, only the main route that cannot be changed or moved was compared with the route  
Figure 11: Comparison graph of width value of PIANC and width of the main route and 95% confidence interval graph of the main route.  
Figure 10: Safety distance between PIANC’s ship navigation and OWFs.  
width. As a result, a location with a width less than 6.4 km appears to have a total of 6 armies. Table 5 displays the summarized result values.  
The result of the safety distance with PIANC shown here is that the value means that it has a safety distance with OWFs, and the closer it is to the value, the less the safety distance decreases, which becomes a risk factor for the safe navigation of the vessel. This water area appears to be a phenomenon in which traffic is dense due to many nearby islands in the selection of the main route, with vertex points 11, 12, 28, 30, 31, and 32 (6 locations) showing a negative value. However, it is judged that it is necessary to understand the characteristics of the relevant sea area in detail or to apply safety regulations for the safe operation of the vessel. Based on a 95% confidence bend, it appears that all values do not overlap with the PIANC when analyzing the entire dataset. As a result, some sea areas' traffic characteristics must be reviewed, but in terms of reliability, they all appear to satisfy 6.4 km or more. In this study, the main route was verified with the value compared with the main route and PIANC working group 161. The width of the route, measured vertically at one vertex point, is the largest in the Busan coastal waters, and it becomes narrower toward the eastern coastal waters. It can be explained as an indirect representation of the complexity of maritime traffic. For the sustainable growth of offshore wind farms and maritime routes, area comparison is effectively performed.