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Safety Edge

Safety EdgeSM Experiencing Pedo

As you drive on a recently resurfaced road, your car drops from the paved road onto an unpaved shoulder. The Safety EdgeSM, a cutting-edge technology, can prevent you from becoming a statistic.

Experiencing Pavement-edge drop-off

You're peacefully driving down a paved road. Your attention wanders for a moment and suddenly you feel your front tire slip onto an unpaved shoulder. Your vehicle lurches to the right. Instinctively, you steer back toward the road, but the car won't seem to move back into the lane. In that terrifying fraction of a second, you panic and wrench the steering wheel further to the left, struggling to get your wheels back on the paved portion of the road.

You are one of the lucky ones. You slowed your car enough to keep from losing control when it lunged up over the drop-off and back onto the pavement. You swerve a little, but manage to bring your car back into your own lane. Heart pounding, you continue on your way.

A pavement–edge drop-off, or PEDO. A drop-off of 2  inches or more

A pavement–edge drop–off, or PEDO. A drop–off of 2 inches or more

You've just experienced a pavement-edge drop-off, or PEDO. A drop-off of 2 inches or more can endanger your life and the lives of those driving near you. If you had been driving more quickly, or if another car had been in the opposite lane when you swerved over the center line, your story might have ended very differently.

The Safety of Safety Edge

An inexpensive, simple technology called the Safety EdgeSM could have prevented that moment of terror. The Safety EdgeSM can save lives.

Not all drivers who encounter a pavement-edge drop-off safely recover. Some lose control of their vehicles and roll over. Others fishtail off the highway or into another car. They swerve into oncoming traffic or crash into a roadside obstacle.

The Safety EdgeSM, a simple and inexpensive countermeasure to pavement-edge drop-offs, offers a tapered transition between the paved surface and the unpaved shoulder where the edge is exposed. Drivers can re-enter the travel lane safely and smoothly.

PEDO can be a nightmare for unsuspecting drivers. When a vehicle slips off the pavement and onto an unpaved shoulder, a steep edge can make re-entering the road extremely difficult. Safety experts have determined that a drop-off of 2 inches or more is unsafe, particularly if the edge is at a near vertical to the surface.

Effective, Low–Cost Installation

Safety Edge requires no extra procedures; the edge is attained by refitting resurfacing equipment to form the correct angle.

Safety Edge requires no extra procedures; the edge is attained by refitting resurfacing equipment to form the correct angle.

Installing the Safety EdgeSM, a 30-degree tapered wedge, is an effective, low-cost PEDO countermeasure. It is installed along each side of the roadway during resurfacing projects. The Safety EdgeSM requires no extra procedures; the edge is attained by refitting resurfacing equipment to form the correct angle.

With the Safety EdgeSM, an angled and compacted transition eliminates the dangerously abrupt drop associated with PEDO. This provides a stronger and more stable pavement edge. Equally important, it is highly durable.

The Safety EdgeSM can be installed along the pavement during any paving project. It allows drivers to recover from drop-offs, even at higher speeds. Even inexperienced drivers are typically able to negotiate a significant drop-off with an appropriately angled edge.

Ongoing research shows that the Safety EdgeSM is effective and improves chances for a safe recovery from a roadway departure. The Safety EdgeSM improves the short- and long-term safety of the roadway. When this durable, practical solution to PEDO is implemented on a national scale, countless highway tragedies can be prevented.

In the opening scenario, you were lucky in your encounter with PEDO. If you had been going faster, or if the drop-off had been more severe, you might have been a fatality.

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Page last modified on May 18, 2012.