Road surface Road surface Road surface 3 ft min. **Not less than 2 ft for low-volume roads 8 ft or less Edge of pavement or shoulder 4 ft rOkaymmended* Guardrail end Bridge with railing but no curb. Mark the inner edge of the railing. 5 ft min. 3.5 ft min. 3341 Not less than 6 ft ** Edge of pavement or shoulder 2 ft min. 4 ft min.