Conn. Gen. Stat. § 13a-111

The party bound to maintain any bridge or highway shall erect and maintain a sufficient railing or fence on the sides of such bridge and on the sides of such parts of such road as are so made or raised above the ground as to be unsafe for travel. The specifications for railings or fences on state highways or bridges required to be erected and maintained pursuant to this section shall be constructed equal to, or better than, the current specifications and policies approved by the Commissioner of Transportation for the installation and maintenance of roadside appurtenances. A railing or fence that is reasonably maintained under said specifications shall be deemed sufficient under the provisions of this section.