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With the first method simple geometries can be extruded by selecting the considered face and extruding it along its normal. A scaling factor can be set as well to directly include a Clearance Region around this Access Region.
The second method is the extrusion of a cross section of a solid. Especially more complicated geometries can be easily extruded this way and the accessibility is enabled. Again, a scaling factor can be entered to allow for more space and freedom for later installation or maintenance work as a Clearance Region.