National Academies Press: OpenBook

A Guide for Reducing Head-On Crashes on Freeways (2008)

Chapter: Section III - Type of Problem Being Addressed

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Suggested Citation:"Section III - Type of Problem Being Addressed." National Academies of Sciences, Engineering, and Medicine. 2008. A Guide for Reducing Head-On Crashes on Freeways. Washington, DC: The National Academies Press. doi: 10.17226/23088.
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Suggested Citation:"Section III - Type of Problem Being Addressed." National Academies of Sciences, Engineering, and Medicine. 2008. A Guide for Reducing Head-On Crashes on Freeways. Washington, DC: The National Academies Press. doi: 10.17226/23088.
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Suggested Citation:"Section III - Type of Problem Being Addressed." National Academies of Sciences, Engineering, and Medicine. 2008. A Guide for Reducing Head-On Crashes on Freeways. Washington, DC: The National Academies Press. doi: 10.17226/23088.
×
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Suggested Citation:"Section III - Type of Problem Being Addressed." National Academies of Sciences, Engineering, and Medicine. 2008. A Guide for Reducing Head-On Crashes on Freeways. Washington, DC: The National Academies Press. doi: 10.17226/23088.
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SECTION III Type of Problem Being Addressed General Description of the Problem In 2003, according to the FARS statistics, there were 366 fatal cross-median head-on crashes on U.S. freeways. Although the number may seem small when compared to the number of overall crashes and to the percentage of all Interstate-related crashes—6 percent—head-on crashes are extremely severe. Data from the FHWA considered the number of fatalities on a national basis. From 1994 to 2002, while fluctuating on an annual basis, median-crossover and wrong-way fatalities on divided highways have increased from 581 to 680 (Ostensen, 2004). The National Highway Transportation Safety Administration (NHTSA) defines a head-on collision as one where the front end of one vehicle collides with the front end of another vehicle while the two vehicles are traveling in opposite directions. For this guide, we are considering only head-on crashes occurring on Interstates and other freeways or expressways. From the FARS database there is no identifiable pattern for these crashes, other than their occurrence on freeways with open medians. North Carolina research showed that head-on collisions take place at all times, days, and seasons, and on horizontal and vertical curves as well as straight and flat sections. There is no predominant cause. Driver behavior is clearly important, including everything from fatigue and improper lane changes to inattention and medical emergencies. Specific Attributes of the Problem Donnell et al. (2002) show that the major contributory factors for median-barrier crashes occurring on Pennsylvania Interstate highways were improper lane changes, driver losing control of vehicle, traveling too fast for weather conditions, exceeding the posted speed limit, and forced vehicle movement or avoidance maneuvers. Exhibit III-1 shows the distribution of fatal crashes for Interstate freeways for 2003. Five percent of the crashes were head-on, and 1 percent was opposite-direction sideswipes. A study in Iowa showed that between 1990 and 1999, though only 2.4 percent of all Interstate crashes were cross- median, they produced 32.7 percent of all the Interstate fatalities during that period. A study by the North Carolina Department of Transportation (NCDOT) in 1998 showed that more than 38 people died and about 300 were injured in cross-median crashes each year (Lynch, 1998). The Florida Department of Transportation found in an unpublished preliminary study that is still underway that 62 percent of all cross-median crashes occurred within 1⁄2 mile and 82 percent occurred within 1 mile of interchange ramp termini (Bane, 2005). Exhibit III-2 shows that, according to 2003 FARS data, 56 percent of these crashes occur on urban Interstates/freeways and 44 percent occur on rural Interstates. Exhibit III-3 shows III-1

that, based on 2005 FARS data, over the years since 1994 urban sections of Interstates have consistently experienced a greater proportion of fatal crashes than those in rural areas. As Exhibit III-4 indicates, 65 percent of those involved in the crossover crashes are male. Individuals in the 15–25 age group make up a large number of those involved in head-on crashes, and the number of head-on crashes per age group declines with increasing age. A study of median crashes for Wisconsin showed that the largest bracket of drivers involved was the 20- to 24-year-old range (McKendry and Noyce, 2005). The percentage generally decreased as the driver age increased. Exhibit III-5 shows the breakdown of fatal crashes by light condition. About 43 percent of crashes occur during the daytime and 54 percent at night, but of those occurring at night, nearly one-half occur on lighted roadways. FARS data are consistent with studies in individual states. A publication from FHWA’s Office of Safety, “Median Barriers,” indicates the following summary statistics (Powers, 2007): SECTION III—TYPE OF PROBLEM BEING ADDRESSED III-2 64% 13% 5% 1%1% 12% 0% 0% 0% 0% 4% Blank Not Collision with Motor Vehicle in Transport Rear-End Head-On Front-to-Side Sideswipe - Same Direction Sideswipe - Opp. Direction Rear-to-Side Rear-to-Rear Other (End Swipes and Others) EXHIBIT III-1 Fatal Crashes by Manner of Collision on Interstates Source: 2003 FARS data. Rural - Interstate 44%Urban - Interstate/ Freeways/ Expressways 56% EXHIBIT III-2 Head-on Crashes on Interstates, Urban vs. Rural Source: 2003 FARS data.

SECTION III—TYPE OF PROBLEM BEING ADDRESSED • There is one crossover fatality annually for about every 200 freeway miles • An average of 250 people are killed annually in freeway crossover crashes • Median crashes are three times more severe than other highway crashes (Stasberg and Crawley, 2005) III-3 4.0% 6.0% 8.0% 10.0% 12.0% 14.0% 16.0% 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 Year Pe rc en ta ge o f F at al C ra sh es Rural Fatal Crashes Urban Fatal Crashes Male 65% Female 34% Unknown 1% EXHIBIT III-3 Percentage of Fatal Crashes on Interstate Highways that are Head On or Sideswipe Opposite Direction Source: 2005 FARS data. EXHIBIT III-4 Fatal Crossover Crashes on Interstates by Gender Source: 2003 FARS data. Daylight 43% Dark 37% Dawn 1% Dusk 2% Dark but Lighted 17% EXHIBIT III-5 Fatal Crossover Crashes on Interstates by Light Condition Source: 2003 FARS data.

SECTION III—TYPE OF PROBLEM BEING ADDRESSED III-4 Mason et al. (2001) used crash and roadway inventory data to characterize cross-median crashes on Pennsylvania Interstates and expressways. Of the cross-median crashes, 15 percent were fatal and 72 percent resulted in occupants being injured. When compared to all crash types on Interstates and expressways, the severity level of cross-median crashes was significantly higher. As Exhibit III-5 indicates, 37 percent of the fatal crossover crashes occur during conditions of darkness. Summary Although a relatively small proportion of total fatalities, according to FHWA data head-on crashes on freeways and Interstates appear to be increasing in recent years. Head-on crashes can occur under a wide range of circumstances. The predominant geometric feature associated with such crashes is the median, including its width as well as the presence (or absence) of a barrier or similar device, and proximity to interchanges. There is evidence that such crashes are associated with high-risk driver behaviors, including excessive speeding and erratic maneuvers.

Next: Section IV - Index of Strategies by ImplementationTimeframe and Relative Cost »
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TRB's National Cooperative Highway Research Program (NCHRP) Report 500, Vol. 20, Guidance for Implementation of the AASHTO Strategic Highway Safety Plan: A Guide for Reducing Head-On Crashes on Freeways, provides strategies that can be employed to reduce head-on crashes on freeways.

In 1998, the American Association of State Highway and Transportation Officials (AASHTO) approved its Strategic Highway Safety Plan, which was developed by the AASHTO Standing Committee for Highway Traffic Safety with the assistance of the Federal Highway Administration, the National Highway Traffic Safety Administration, and the Transportation Research Board Committee on Transportation Safety Management. The plan includes strategies in 22 key emphasis areas that affect highway safety. The plan's goal is to reduce the annual number of highway deaths by 5,000 to 7,000. Each of the 22 emphasis areas includes strategies and an outline of what is needed to implement each strategy.

Over the next few years the National Cooperative Highway Research Program (NCHRP) will be developing a series of guides, several of which are already available, to assist state and local agencies in reducing injuries and fatalities in targeted areas. The guides correspond to the emphasis areas outlined in the AASHTO Strategic Highway Safety Plan. Each guide includes a brief introduction, a general description of the problem, the strategies/countermeasures to address the problem, and a model implementation process.

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