The University of Tennessee, Knoxville


Safety Improvements on High Risk Rural Roads

by Dr. Airton Kohls - Source FHWA Office of Safety

The Federal Highway Administration (FHWA) has just released a Manual providing information and selection criteria associated with safety improvements on High Risk Rural Roads (HRRR). It includes the following topics:

Figure 1 - Safety Treatment Categories

With the large number of safety treatments available, it can be challenging for practitioners to select the most effective treatment to implement with limited funds. The manual is intended to assist an agency in understanding the effectiveness of safety improvements on HRRR to aid in the treatment selection process.

The manual is organized by safety treatment categories as listed in Figure 1.

At the beginning of each treatment category section, a treatment matrix provides an overview of benefits and costs associated with each safety improvement in the section. The matrix may be used to help narrow the list of potential treatments by sorting through criteria specific to the practitioner's needs and available resources. For example, if practitioner would like to identify an intersection treatment with a maximum initial cost, the matrix can be used to narrow the treatments to only those falling within the maximum range. Figure 2 on page 7 shows an abbreviated version of the Horizontal Curve Treatment Matrix.

The manual also provides information to determine a range of treatment options based on the resources available to implement a treatment.

The following are some of the safety improvements for HRRR explored in the manual:

Horizontal Curves:

Signalized Intersections:

Figure 2 - Horizontal Curve Treatment Matrix

Unsignalized Intersections:

Non-motorized User:

For additional information and for a free copy of the Safety Improvements on High Risk Rural Roads Manual go to: http://safety.


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