A connection to a bridge is also known as a transition or bridge approach system. They are required to provide continuity of protection when two different barrier systems are connected. The function of a bridge approach system is to gradually increase the lateral stiffness of the safety barrier system and reduce the potential for vehicle pocketing. The most common types of bridge approach systems increase the lateral stiffness of the system by transitioning from W-beam to Thrie-beam. In addition, post spacing is reduced prior to connecting to the downstream rigid barrier.