1, which cannot be covered by road debris, such as traffic lights, monitoring, advertising signs and tree posts.

2. Other traffic facilities should not be affected.

3, shall not affect the general sight distance of parking people on the road, so as not to hinder the smooth traffic.

4. Keep a safe distance from all kinds of buildings on the roadside.

5. Don't be too close to the doors and windows of the building, the security booth and the entrance of the exit.

6, especially on the highway, the sign spacing should not be less than 100 meters, and the minimum spacing of road signs in ordinary urban areas should not be less than 30 meters.