Minnesota Department of Transportation

511 Travel Info

State Aid for Local Transportation

Safety edge

Safety edge

The safety edge is a simple, practical and cost-effect safety measure that addresses pavement edge drop-offs. Current research indicates that vertical interfaces between pavement edges and shoulder material become hazardous when a driver drifts off the road. These steep inclines can lead to “tire scrubbing” which can result in over-steering and ultimately, fatal collisions.

tire scrubbing
Photo source: AAA Foundation for Highway Safety

This is a typical diagram for a crash caused by tire scrubbing. The vehicle at left scrubbed the edge of the pavement, and when it returned, the driver overcorrected, lost control, crossed into the adjacent lane, and struck an oncoming vehicle.

The Safety edge resolves this issue by tapering pavement at a 30˚- 35˚ angle from the horizontal to newly graded material. It can be applied during any normal project and uses <1% of additional asphaltic material.

safety edge

safety edge
Photo source: FHWA

Benefits of the safety edge:

  • Improves pavement density at edge
  • Stronger interface between pavement and graded material
  • Less raveling at pavement edge
  • Eliminates "tire scrubbing"
  • Increased durability and longevity of pavement
  • Reduces tort law liability

Information and resources