Effects of roadway geometric features on run-off road crashes on the Florida State Highway System

Run-off-road (ROR) crashes have increasingly become a serious concern for transportation officials in the State of Florida. These types of crashes have increased proportionally in recent years statewide and have been the focus of the Florida Department of Transportation. The goal of this research was to develop statistical models that can be used to investigate the possible causal relationships between roadway geometric features and ROR crashes on Florida's rural and urban principal arterials. ^ In this research, Zero-Inflated Poisson (ZIP) and Zero-Inflated Negative Binomial (ZINB) Regression models were used to better model the excessive number of roadway segments with no ROR crashes. Since Florida covers a diverse area and since there are sixty-seven counties, it was divided into four geographical regions to minimize possible unobserved heterogeneity. Three years of crash data (2000–2002) encompassing those for principal arterials on the Florida State Highway System were used. Several statistical models based on the ZIP and ZINB regression methods were fitted to predict the expected number of ROR crashes on urban and rural roads for each region. Each region was further divided into urban and rural areas, resulting in a total of eight crash models. A best-fit predictive model was identified for each of these eight models in terms of AIC values. The ZINB regression was found to be appropriate for seven of the eight models and the ZIP regression was found to be more appropriate for the remaining model. To achieve model convergence, some explanatory variables that were not statistically significant were included. Therefore, strong conclusions cannot be derived from some of these models. ^ Given the complex nature of crashes, recommendations for additional research are made. The interaction of weather and human condition would be quite valuable in discerning additional causal relationships for these types of crashes. Additionally, roadside data should be considered and incorporated into future research of ROR crashes. ^

In Australia are people born in other countries at higher risk of road trauma than locally born people?

This study examined whether people born in other countries had higher rates of death and hospitalization due to road crashes than people born in Australia. Data on deaths that occurred in the whole of Australia between 1994 and 1997 and hospitalizations that occurred in the state of New South Wales, Australia, between I July 1995 and 30 June 1997 due to road crashes were analyzed. The rates of death and hospitalization, adjusted for age and area of residence, were calculated using population data from the 1996 Australian census. The study categorized people born in other countries according to the language (English speaking, non-English speaking) and the road convention (left-hand side, right-hand side) of their country of birth. Australia has the left-hand side driving convention. The study found that drivers born in other countries had rates of death or hospitalization due to road trauma equal to or below those of Australian born drivers. In contrast, pedestrians born in other countries, especially older pedestrians had higher rates of death and hospitalization due to road crashes. Pedestrians aged 60 years or more born in non-English speaking countries where traffic travels on the right-hand side of the road had risks about twice those of Australian born pedestrians in the same age group. (C) 2003 Elsevier Ltd. All rights reserved.

Road Safety Audit for US 52 in Dubuque County from IA 136 to the NCL of Dubuque, 2008

A section of US 52 between Dubuque and Luxemburg, Iowa, was listed in the top 5% of Iowa highways for severe crashes involving impaired drivers and single vehicle run-off-road crashes during 2001–2005, and several crashes have occurred on this roadway near the towns of Luxemburg, Holy Cross, and Rickardsville, Iowa, many on curves. Staff and officials from the Iowa Department of Transportation (Iowa DOT), Iowa State Patrol, Governor’s Traffic Safety Bureau, Federal Highway Administration, Center for Transportation Research and Education Dubuque County, and a retired fire chief met to review crash data and discuss potential safety improvements to U.S. Highway 52. This report outlines the findings and recommendations of the road safety audit team to address the safety concerns on this US 52 corridor and explains several mitigation strategies that the Iowa DOT District 6 Office has selected.

Road Safety Audit for County Road X-37, from the Intersection of G-62 to the East Corporate Limits of Columbus City in Louisa County, Iowa, 2009

A road safety audit was conducted for a 7.75 mile section of County Road X-37 in Louisa County, Iowa. In 2006, the average annual daily traffic on this roadway was found to be 680 vehicles per day. Using crash data from 2001 to 2007, the Iowa Department of Transportation (Iowa DOT) has identified this roadway as being in the highest 5% of local rural roads in Iowa for single-vehicle runoff- road crashes. Considering these safety data, the Louisa County Engineer requested that a road safety audit be conducted to identify areas of safety concerns and recommend low-cost mitigation to address those concerns. Staff and officials from the Iowa DOT, Governor’s Traffic Safety Bureau, Federal Highway Administration, Institute for Transportation, and local law enforcement and transportation agencies met to review crash data and discuss potential safety improvements to this segment of X-37. This report outlines the findings and recommendations of the road safety audit team to address the safety concerns on this X-37 corridor and explain several selected mitigation strategies.

Road Safety Audit for County Road H-46 from Redwood Avenue to the Southerly Corporate Limits of Fairfield in Jefferson County, Iowa, 2010

Jefferson County Road H-46 from Redwood Avenue to the southeast corporate limits (SCL) of Fairfield, Iowa, is a paved roadway approximately 6.5 miles long made of asphaltic concrete pavement with curvilinear alignment. The roadway consists of a 22 ft wide pavement, last overlaid in 2002, with 3 to 4 ft wide earth shoulders. Traffic estimates indicated volumes ranging from 500 to 1,590 vehicles per day, with numbers increasing as the route nears Fairfield. This roadway was found to be among the highest 5 percent of similar Iowa roadways in terms of severity of run-off-road crashes. In response, Iowa Department of Transportation (Iowa DOT) requested a road safety audit to examine the roadway and suggest possible mitigation. Representatives from the Iowa DOT, Federal Highway Administration, Institute for Transportation, local law enforcement, and local government met to review crash data and discuss potential safety improvements to this segment H-46. This report outlines the findings and recommendations of the road safety audit team for addressing the safety concerns on this roadway.

Road Safety Audits for County Road X-23 from IA 2 to the South Corporate Limits of West Point and for County Road W-62 from US 218 to IA 27 in Lee County, Iowa, 2010

On October 20–21, 2009, two road safety audits were conducted in Lee County, Iowa: one for a 6 mile section of County Road X-23 from IA 2 to the south corporate limits of West Point and one for a 9.7 mile section of County Road W-62 from US 218 to IA 27. Both roads have high severe crash histories for the years of 2001 through 2008. Using these crash data, the Iowa Department of Transportation (Iowa DOT) has identified County Road X-23 as being in the top 5 percent of similar roads for run-off-road crashes. The Iowa DOT lists County Road W-62 as a high-risk rural road that has above-average crash numbers and is eligible for funding under the Federal High-Risk Rural Road Program. Considering these issues, the Lee County Engineer and Iowa DOT requested that road safety audits be conducted to address the safety concerns and to suggest possible mitigation strategies.

Aortic rupture in high-speed skiing crashes

BACKGROUND: New equipment and techniques in winter sports, such as carving skis and snowboards, have brought up new trauma patterns into the spectrum of leisure trauma. The injuries resemble high-energy trauma known from road crashes. The aim of the present study was to assess the incidence of acute traumatic descending aortic rupture in recreational skiing-crashes. MATERIAL: Between January 1995 and December 2004, 22 patients were admitted to our hospital for aortic rupture. Four patients had skiing crashes (18.2%). Mean age was 31 years, all patients were male. In two cases, aortic rupture was associated with fractures of the upper and lower extremities. One patient additionally had a cerebral contusion with an initial Glasgow Coma Scale score of 13. In two patients, isolated aortic rupture was diagnosed. RESULTS: Two patients were treated by graft interposition, and one by endograft. One patient arrived under mechanical resuscitation without blood pressure. He died at admission. He had been observed for 5 hours in another hospital, complaining of severe intrascapular back pain, before transport to our trauma unit for unknown bleeding. In the other three cases, treatment was successful. CONCLUSION: Rescue services and paramedics should be aware of this new type of injury. Acute aortic rupture has to be considered as possible injury in high velocity skiing crashes.

Advances in neurotrauma in Australia 1970-2000

The management of neurotrauma in Australia has been one of the significant public health triumphs during the last 30 years of the 20th century. State and national government agencies act in a coordinated fashion to collect data and to promote research on how to manage neurotrauma patients. Between 1970 and 1995, fatalities from road accidents decreased by 47%. Hospital admissions have decreased by 40% despite a 40% increase in the population and a 120% increase in registered vehicles. Fatalities per 10,000 registered vehicles were 8.05% in 1970 and they fell to 1.84% per vehicles in 1995, while fatalities per 10;000 population were 3 in 1970 falling to 1.11 in 1995. Hospitalization from road crashes decreased 23% between March 1988 and March 1997. Public education has steadily improved, backed by the state public health sources. A uniform code of road safety laws has been adopted, backed by legislation and legal penalties and increasing police enforcement. Clinical care of patients has improved as a result of faster communications, tele-medicine, trauma systems, the CT scanner; intensive care units, and improved monitoring. Patient rehabilitation and counseling are now carried out at units accredited by the Australian Council on Health Care Standards.

Evaluation of Rumble Stripes on Low-Volume Rural Roads in Iowa—Phase II Final Report, November 2011

Single-vehicle run-off-road crashes are the most common crash type on rural two-lane Iowa roads. Rumble strips have proven effective in mitigating these crashes, but the strips are commonly installed in paved shoulders on higher-volume roads that are owned by the State of Iowa. Lower-volume paved rural roads owned by local agencies do not commonly feature paved shoulders but frequently experience run-off-road crashes. This project involved installing rumble stripes, which are a combination of conventional rumble strips with a painted edge line placed on the surface of the milled area, along the edge of the travel lanes, but at a narrow width to avoid possible intrusion into the normal vehicle travel paths. The research described in this report was part of a project funded by the Federal Highway Administration, Iowa Highway Research Board, and Iowa Department of Transportation to evaluate the effectiveness of edge-line rumble strips in Iowa. The project evaluated the effectiveness of rumble stripes in reducing run-off-road crashes and in improving the longevity and wet-weather visibility of edge-line markings. This project consisted of two phases. The first phase was to select pilot study locations, select a set of test sites, install rumble stripes, summarize lessons learned during installation, and provide a preliminary assessment of the rumble stripes’ performance. The purpose of this report was to document results from Phase II. A before and after crash analysis was conducted to assess whether use of the treatment had resulted in fewer crashes. However, due to low sample size, results of the analysis were inconclusive. Lateral position was also evaluated before and after installation of the treatment to determine whether vehicles engaged in better lane keeping. Pavement marking wear was also assessed.

Evaluation of Rumble Stripes on Low-Volume Rural Roads in Iowa—Phase I, TR-577, 2009

Single-vehicle run-off-road crashes are the most common crash type on rural two-lane Iowa roads. Rumble strips have been proven effective in mitigating these crashes, but these strips are commonly installed in paved shoulders adjacent to higher-volume roads owned by the State of Iowa. Lower-volume paved rural roads owned by local agencies do not commonly feature paved shoulders but frequently experience run-off-road crashes. This project involved installing “rumble stripes,” which are a combination of conventional rumble strips with a painted edge line placed on the surface of the milled area, along the edge of the travel lanes but at a narrow width to avoid possible intrusion into the normal vehicle travel paths. Candidate locations were selected from a list of paved local rural roads that were most recently listed in the top 5% of roads for run-off-road crashes in Iowa. Horizontal curves were the most favored locations for rumble stripe installation because they commonly experience roadway departure crashes. The research described in this report was part of a project funded by the Federal Highway Administration, Iowa Highway Research Board, and Iowa Department of Transportation to evaluate the effectiveness of edge line rumble strips in Iowa. The project evaluated the effectiveness of “rumble stripes” in reducing run-off-road crashes and in improving the longevity and wet weather visibility of edge line markings. This project consists of two phases. The first phase was to select pilot study locations, select a set of test sites, install rumble stripes, summarize lessons learned during installation, and provide a preliminary assessment of the rumble stripes’ performance. This information is summarized in this report. The purpose of the second phase is to provide a more long-term assessment of the performance of the pavement markings, conduct preliminary crash assessments, and evaluate lane keeping. This will result in a forthcoming second report.

Safety Benefits of Paved Shoulders, 2009

Single vehicle run-off-road (ROR) crashes are the largest type of fatal passenger vehicle crash in the United States (NCHRP 500 2003). In Iowa, ROR crashes accounted for 36% of rural crashes and 9% of total crashes in 2006. Run-off-road crashes accounted for more than 61.8% of rural fatal crashes and 32.6% of total fatal crashes in Iowa in 2006. Paved shoulders are a potential countermeasure for ROR crashes. Several studies are available which have generally indicated that paved shoulders are effective in reducing crashes. However, the number of studies that quantify the benefits are limited. The research described in this report evaluates the effectiveness of paved shoulders. Model results indicated that covariate for speed limit was not significant at the 0.05 confidence level and was removed from the model. All other variables which resulted in the final model were significant at the 0.05 confidence level. The final model indicated that season of the year was significant in indicating expected number of total monthly crashes with a higher number of crashes occurring in the winter and fall than for spring and summer. The model also indicated that presence of rumble strips, paved shoulder width, unpaved shoulder width, and presence of a divided median were correlated with a decrease in crashes. The model also indicated that roadway sections with paved shoulders had fewer crashes in the after period as compared to both the before period and control sections. The actual impact of paved shoulders depends on several other covariates as indicated in the final model such as installation year and width of paved shoulders. However, comparing the expected number of total crashes before and after installation of paved shoulders for several scenarios indicated around a 4.6% reduction in the expected number of monthly crashes in the after period.

Sleepiness, sleep-disordered breathing, and accident risk factors in commercial vehicle drivers

Sleep-disordered breathing and excessive sleepiness may be more common in commercial vehicle drivers than in the general population. The relative importance of factors causing excessive sleepiness and accidents in this population remains unclear. We measured the prevalence of excessive sleepiness and sleep-disordered breathing and assessed accident risk factors in 2,342 respondents to a questionnaire distributed to a random sample of 3,268 Australian commercial vehicle drivers and another 161 drivers among 244 invited to undergo polysomnography. More than half (59.6%) of drivers had sleep-disordered breathing and 15.8% had obstructive sleep apnea syndrome. Twenty-four percent of drivers had excessive sleepiness. Increasing sleepiness was related to an increased accident risk. The sleepiest 5% of drivers on the Epworth Sleepiness Scale and Functional Outcomes of Sleep Questionnaire had an in-creased risk of an accident (odds ratio [OR] 1.91, p = 0.02 and OR 2.23, p < 0.01, respectively) and multiple accidents (OR 2.67, p < 0.01 and OR 2.39, p = 0.01), adjusted for established risk factors. There was an increased accident risk with narcotic analgesic use (OR 2.40, p < 0.01) and antihistamine use (OR 3.44, p = 0.04). Chronic excessive sleepiness and sleep-disordered breathing are common in Australian commercial vehicle drivers. Accident risk was related to increasing chronic sleepiness and antihistamine and narcotic analgesic use.

Full road closure for work zone operations : a cross-cutting study : reducing congestion and crashes through full road closure for maintenance and construction.

"EDL# 13795."

Full road closure for work zone operations : a case study : accelerating construction and reducing crashes during the rehabilitation of a major downtown route : M-10 Lodge Freeway in Detroit, Michigan.

"FHWA-HOP-05-013"--P. [4] of cover.