For sheilding an embankment, provide a minimum of 2 feet of barrier-to-embankment distance to prevent the posts from coming out of the side slope upon impact.
Place roadside barriers as far from the road edge as possible. Preferably, if practical, place beyond the "shy line," or the distance from the edge of the traveled way that an obstacle will not be perceived as an immediate hazard by a typical driver. The shy line offset distance is seldom a controlling criterion for barrier placement. As long as the barrier is located beyond the perceived shoulder of a roadway, it will have minimum impact on driver speed or lane position. The distance between the barrier and obstruction must always allow for maximum barrier deflection. Refer to the AASHTO Roadside Design Guide for suggested shy-line offset values.