What is the flare rate at 30 MPH for barriers?

The flare rate for barriers at 30 MPH is indeed 8:1. This means that for every 1 unit of height, the distance from the edge of the obstacle (or barrier) should be 8 units away. The flare rate is essential in traffic control because it helps to safely redirect traffic around any roadside obstacles, enhancing both driver awareness and vehicle safety.

At a speed of 30 MPH, the 8:1 flare rate is designed to provide a sufficient recovery area and to ensure that any vehicle that might leave the roadway has enough distance to return to the traveled way safely. It establishes the necessary tapering and positioning of barriers to guide drivers and reduce the potential for collisions. This standard is based on research and best practices that enable traffic control supervisors to make informed decisions about barrier placement and the safeguarding of both road workers and motorists.

The other rates are established for different speed limits and scenarios. For instance, a 6:1 flare might apply at a lower speed, while higher rates like 10:1 or 12:1 may be implemented at higher speeds or in situations requiring greater lateral distance from the roadway. The choice of the 8:1 ratio ensures a balanced approach that considers both speed and safety.