Center Line Buffer Areas for Safety: Implementation Guidelines and Tool

Roadway departure crashes account for half of all fatalities every year, more than 18,000, with more than 5,000 fatalities resulting from head-on crashes. These crashes occur primarily on undivided, high-speed, rural roads with vehicles traveling in opposite directions, often separated only by a center line pavement marking and possibly a rumble strip. National Cooperative Highway Research Program (NCHRP) Research Report 995: Guidelines for Treatments to Mitigate Opposite Direction Crashes provides guidelines for selecting appropriate safety countermeasures for opposite-direction crashes. The supporting research project, NCHRP Project 17-66, “Guidance for Selection of Appropriate Countermeasures for Opposite Direction Crashes,” found that center line buffer areas reduce opposite-direction crash fatalities significantly and are used around the United States. NCHRP Project 17-66 researchers developed crash modification factors for center line buffer areas of 2 ft, 4 ft, and 6 ft in width. However, challenges arise during the implementation of center line buffer areas. Transportation agencies must often work within existing roadway pavement areas to implement low-cost safety countermeasures. In cases where the roadway cannot be widened to accommodate the center line buffer area, a practitioner must consider the roadway context and decide between narrowing the lanes or shoulders. Guidelines are needed to inform designers on the overall safety performance of various roadway cross sections with a center line buffer area. The aim is to determine which safety benefit between center line buffer areas and wider lanes and shoulders will guide the decision on where to reallocate pavement area. Research is needed to develop guidelines and a tool to support the implementation of center line buffer areas so that practitioners can weigh the geometric and operational factors that affect the safety performance of center line buffer areas. OBJECTIVE: The objective of this project is to develop guidelines and a tool for the implementation of center line buffer areas, with a focus on rural two-lane highways. The project will evaluate the safety benefits of center line buffer areas while considering the reallocation of other cross-sectional elements and develop criteria for implementation.

• Record URL:
  • http://apps.trb.org/cmsfeed/TRBNetProjectDisplay.asp?ProjectID=5682
• Supplemental Notes:
  • Contract to a Performing Organization has not yet been awarded.

Language

• English

Project

• Funding: $250000
• Contract Numbers:

  Project 17-134

• Sponsor Organizations:

  National Cooperative Highway Research Program

  Transportation Research Board
  500 Fifth Street, NW
  Washington, DC  United States  20001

  American Association of State Highway and Transportation Officials (AASHTO)

  444 North Capitol Street, NW
  Washington, DC  United States  20001

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Project Managers:

  Turner, Anne-Marie

• Start Date: 20241202
• Expected Completion Date: 0
• Actual Completion Date: 0

Subject/Index Terms

• TRT Terms: Center lines; Frontal crashes; Highway design; Highway safety; Rural highways; Two lane highways
• Subject Areas: Design; Highways; Safety and Human Factors;

Filing Info

• Accession Number: 01919456
• Record Type: Research project
• Source Agency: Transportation Research Board
• Contract Numbers: Project 17-134
• Files: TRB, RIP
• Created Date: May 23 2024 10:00AM