According to EN 1991-1-4, Table 4.1.
|0||0||Sea or coastal area exposed to the open sea.|
|1||I||Lakes or flat and horizontal area with negligible vegetation and without obstacles.|
|2||II||Area with low vegetation such as grass and isolated obstacles (trees, buildings) with separations of at least 20 obstacle heights.|
|3||III||Area with regular cover of vegetation or buildings or with isolated obstacles with separations of maximum 20 obstacle heights (such as villages, suburban terrain, permanent forest).|
|4||IV||Area in which at least 15 % of the surface is covered with buildings and their average height exceeds 15 m.|