Left-turn phase: permissive, protected, or both? A quasi-experimental design in New York City.
Chen, Li; Chen, Cynthia; Ewing, Reid
2015-03-01
The practice of left-turn phasing selection (permissive, protected-only, or both) varies from one locality to another. The literature evidence on this issue is equally mixed and insufficient. In this study, we evaluate the safety impacts of changing left-turn signal phasing from permissive to protected/permissive or protected-only at 68 intersections in New York City using a rigorous quasi-experimental design accompanied with regression modeling. Changes in police reported crashes including total crashes, multiple-vehicle crashes, left-turn crashes, pedestrian crashes and bicyclist crashes were compared between before period and after period for the treatment group and comparison group by means of negative binomial regression using a Generalized Estimating Equations (GEE) technique. Confounding factors such as the built environment characteristics that were not controlled in comparison group selection are accounted for by this approach. The results show that the change of permissive left-turn signal phasing to protected/permissive or protected-only signal phasing does not result in a significant reduction in intersection crashes. Though the protected-only signal phasing does reduce the left-turn crashes and pedestrian crashes, this reduction was offset by a possible increase in over-taking crashes. These results suggest that left-turn phasing should not be treated as a universal solution that is always better than the permissive control for left-turn vehicles. The selection and implementation of left-turn signal phasing needs to be done carefully, considering potential trade-offs between safety and delay, and many other factors such as geometry, traffic flows and operations. Copyright © 2014 Elsevier Ltd. All rights reserved.
Countermeasures for fatal crashes on two-lane rural roads.
DOT National Transportation Integrated Search
2001-05-01
In the first phase of this study, characteristics of crashes on two-lane rural roads were summarized and compared to all crashes. Also, one-mile sections having high crash rates were identified. In this phase of the study, a detailed analysis was con...
Iraeus, Johan; Lindquist, Mats
2016-10-01
Frontal crashes still account for approximately half of all fatalities in passenger cars, despite several decades of crash-related research. For serious injuries in this crash mode, several authors have listed the thorax as the most important. Computer simulation provides an effective tool to study crashes and evaluate injury mechanisms, and using stochastic input data, whole populations of crashes can be studied. The aim of this study was to develop a generic buck model and to validate this model on a population of real-life frontal crashes in terms of the risk of rib fracture. The study was conducted in four phases. In the first phase, real-life validation data were derived by analyzing NASS/CDS data to find the relationship between injury risk and crash parameters. In addition, available statistical distributions for the parameters were collected. In the second phase, a generic parameterized finite element (FE) model of a vehicle interior was developed based on laser scans from the A2MAC1 database. In the third phase, model parameters that could not be found in the literature were estimated using reverse engineering based on NCAP tests. Finally, in the fourth phase, the stochastic FE model was used to simulate a population of real-life crashes, and the result was compared to the validation data from phase one. The stochastic FE simulation model overestimates the risk of rib fracture, more for young occupants and less for senior occupants. However, if the effect of underestimation of rib fractures in the NASS/CDS material is accounted for using statistical simulations, the risk of rib fracture based on the stochastic FE model matches the risk based on the NASS/CDS data for senior occupants. The current version of the stochastic model can be used to evaluate new safety measures using a population of frontal crashes for senior occupants. Copyright © 2016 Elsevier Ltd. All rights reserved.
Characteristics and contributory causes related to large truck crashes (phase II) : all crashes.
DOT National Transportation Integrated Search
2012-03-01
Statistics clearly demonstrate that large-truck crashes contribute to a significant percentage of high-severity crashes. It is : therefore important for the highway safety community to identify the characteristics and contributory causes of these typ...
Safety performance of traffic phases and phase transitions in three phase traffic theory.
Xu, Chengcheng; Liu, Pan; Wang, Wei; Li, Zhibin
2015-12-01
Crash risk prediction models were developed to link safety to various phases and phase transitions defined by the three phase traffic theory. Results of the Bayesian conditional logit analysis showed that different traffic states differed distinctly with respect to safety performance. The random-parameter logit approach was utilized to account for the heterogeneity caused by unobserved factors. The Bayesian inference approach based on the Markov Chain Monte Carlo (MCMC) method was used for the estimation of the random-parameter logit model. The proposed approach increased the prediction performance of the crash risk models as compared with the conventional logit model. The three phase traffic theory can help us better understand the mechanism of crash occurrences in various traffic states. The contributing factors to crash likelihood can be well explained by the mechanism of phase transitions. We further discovered that the free flow state can be divided into two sub-phases on the basis of safety performance, including a true free flow state in which the interactions between vehicles are minor, and a platooned traffic state in which bunched vehicles travel in successions. The results of this study suggest that a safety perspective can be added to the three phase traffic theory. The results also suggest that the heterogeneity between different traffic states should be considered when estimating the risks of crash occurrences on freeways. Copyright © 2015 Elsevier Ltd. All rights reserved.
Optimization of vehicle deceleration to reduce occupant injury risks in frontal impact.
Mizuno, Koji; Itakura, Takuya; Hirabayashi, Satoko; Tanaka, Eiichi; Ito, Daisuke
2014-01-01
In vehicle frontal impacts, vehicle acceleration has a large effect on occupant loadings and injury risks. In this research, an optimal vehicle crash pulse was determined systematically to reduce injury measures of rear seat occupants by using mathematical simulations. The vehicle crash pulse was optimized based on a vehicle deceleration-deformation diagram under the conditions that the initial velocity and the maximum vehicle deformation were constant. Initially, a spring-mass model was used to understand the fundamental parameters for optimization. In order to investigate the optimization under a more realistic situation, the vehicle crash pulse was also optimized using a multibody model of a Hybrid III dummy seated in the rear seat for the objective functions of chest acceleration and chest deflection. A sled test using a Hybrid III dummy was carried out to confirm the simulation results. Finally, the optimal crash pulses determined from the multibody simulation were applied to a human finite element (FE) model. The optimized crash pulse to minimize the occupant deceleration had a concave shape: a high deceleration in the initial phase, low in the middle phase, and high again in the final phase. This crash pulse shape depended on the occupant restraint stiffness. The optimized crash pulse determined from the multibody simulation was comparable to that from the spring-mass model. From the sled test, it was demonstrated that the optimized crash pulse was effective for the reduction of chest acceleration. The crash pulse was also optimized for the objective function of chest deflection. The optimized crash pulse in the final phase was lower than that obtained for the minimization of chest acceleration. In the FE analysis of the human FE model, the optimized pulse for the objective function of the Hybrid III chest deflection was effective in reducing rib fracture risks. The optimized crash pulse has a concave shape and is dependent on the occupant restraint stiffness and maximum vehicle deformation. The shapes of the optimized crash pulse in the final phase were different for the objective functions of chest acceleration and chest deflection due to the inertial forces of the head and upper extremities. From the human FE model analysis it was found that the optimized crash pulse for the Hybrid III chest deflection can substantially reduce the risk of rib cage fractures. Supplemental materials are available for this article. Go to the publisher's online edition of Traffic Injury Prevention to view the supplemental file.
Determination of the maximum MGS mounting height : phase II detailed analysis with LS-DYNA.
DOT National Transportation Integrated Search
2012-12-01
Determination of the maximum Midwest Guardrail System (MGS) mounting height was performed in two phases. : Phase I concentrated on crash testing: two full-scale crash tests were performed on the MGS with top-rail mounting heights : of 34 in. (864 mm)...
Roadway median treatments : phase 1 and phase 2.
DOT National Transportation Integrated Search
2010-02-01
This research project examined relationships among crash rates, cross section design elements, and other operational attributes of multilane urban and suburban roadways in Arkansas. Crash rates for four cross section categories (roadways with no medi...
CABLE MEDIAN BARRIER FAILURE ANALYSIS AND REMEDIATION, PHASE II
DOT National Transportation Integrated Search
2013-06-20
On divided roadways, cross-median fatalities are disproportionately overrepresented in fatal and serious injury crashes. Many state DOTs sought to mitigate cross-median crash risk by installing cable median barriers. Despite increased crash rates, st...
U 26: Enhanced finite element analysis crash model of tractor-trailers (Phase C).
DOT National Transportation Integrated Search
2010-09-01
NTRCI sponsored the research team of Battelle, Oak Ridge National Laboratory (ORNL) and the University of Tennessee at Knoxville (UTK) to conduct a : three-phase investigation to enhance and refine a FE model for simulating tractor-semitrailer crash ...
Evaluation of rumble stripes on low-volume rural roads in Iowa : phase II.
DOT National Transportation Integrated Search
2011-11-01
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...
Structural and topological phase transitions on the German Stock Exchange
NASA Astrophysics Data System (ADS)
Wiliński, M.; Sienkiewicz, A.; Gubiec, T.; Kutner, R.; Struzik, Z. R.
2013-12-01
We find numerical and empirical evidence for dynamical, structural and topological phase transitions on the (German) Frankfurt Stock Exchange (FSE) in the temporal vicinity of the worldwide financial crash. Using the Minimal Spanning Tree (MST) technique, a particularly useful canonical tool of the graph theory, two transitions of the topology of a complex network representing the FSE were found. The first transition is from a hierarchical scale-free MST representing the stock market before the recent worldwide financial crash, to a superstar-like MST decorated by a scale-free hierarchy of trees representing the market’s state for the period containing the crash. Subsequently, a transition is observed from this transient, (meta)stable state of the crash to a hierarchical scale-free MST decorated by several star-like trees after the worldwide financial crash. The phase transitions observed are analogous to the ones we obtained earlier for the Warsaw Stock Exchange and more pronounced than those found by Onnela-Chakraborti-Kaski-Kertész for the S&P 500 index in the vicinity of Black Monday (October 19, 1987) and also in the vicinity of January 1, 1998. Our results provide an empirical foundation for the future theory of dynamical, structural and topological phase transitions on financial markets.
Evaluation of rumble stripes on low-volume rural roads in Iowa--phase I : final report, July 2009.
DOT National Transportation Integrated Search
2009-07-01
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-volum...
DOT National Transportation Integrated Search
1997-01-01
The purpose of this Phase 2 Study is to compare national motor vehicle accident projections : made from the Crash Avoidance Research Data base (CARDfile) with national motor : vehicle accident projections made from other data bases. For the most part...
DOT National Transportation Integrated Search
2010-03-01
Traffic safety has become one of the most critical issues facing transportation agencies across the nation. In 2006, about 43,000 people were killed, and another 290,000 were seriously injured in crashes on public roadways in the United States. Accor...
Safety effects of exclusive and concurrent signal phasing for pedestrian crossing.
Zhang, Yaohua; Mamun, Sha A; Ivan, John N; Ravishanker, Nalini; Haque, Khademul
2015-10-01
This paper describes the estimation of pedestrian crash count and vehicle interaction severity prediction models for a sample of signalized intersections in Connecticut with either concurrent or exclusive pedestrian phasing. With concurrent phasing, pedestrians cross at the same time as motor vehicle traffic in the same direction receives a green phase, while with exclusive phasing, pedestrians cross during their own phase when all motor vehicle traffic on all approaches is stopped. Pedestrians crossing at each intersection were observed and classified according to the severity of interactions with motor vehicles. Observation intersections were selected to represent both types of signal phasing while controlling for other physical characteristics. In the nonlinear mixed models for interaction severity, pedestrians crossing on the walk signal at an exclusive signal experienced lower interaction severity compared to those crossing on the green light with concurrent phasing; however, pedestrians crossing on a green light where an exclusive phase was available experienced higher interaction severity. Intersections with concurrent phasing have fewer total pedestrian crashes than those with exclusive phasing but more crashes at higher severity levels. It is recommended that exclusive pedestrian phasing only be used at locations where pedestrians are more likely to comply. Copyright © 2015. Published by Elsevier Ltd.
Response of DP 600 products to dynamic impact loads
NASA Astrophysics Data System (ADS)
Clark, Deidra Darcell
The objective of this study was to compare the microstructural response of various DP 600 products subjected to low velocity, dynamic impact tests, typically encountered in a car crash. Since the response of steel is sensitive to its microstructure as controlled by the alloying elements, phase content, and processing; various DP 600 products may respond differently to crashes. The microstructure before and after dynamic impact deformation at 5 and 10 mph was characterized with regards to grain size, morphology, and phase content among vendors A, B, and C to evaluate efficiency in absorbing energy mechanisms during a crash simulated by dynamic impact testing in a drop tower.
Crash pulse optimization for occupant protection at various impact velocities.
Ito, Daisuke; Yokoi, Yusuke; Mizuno, Koji
2015-01-01
Vehicle deceleration has a large influence on occupant kinematic behavior and injury risks in crashes, and the optimization of the vehicle crash pulse that mitigates occupant loadings has been the subject of substantial research. These optimization research efforts focused on only high-velocity impact in regulatory or new car assessment programs though vehicle collisions occur over a wide range of velocities. In this study, the vehicle crash pulse was optimized for various velocities with a genetic algorithm. Vehicle deceleration was optimized in a full-frontal rigid barrier crash with a simple spring-mass model that represents the vehicle-occupant interaction and a Hybrid III 50th percentile male multibody model. To examine whether the vehicle crash pulse optimized at the high impact velocity is useful for reducing occupant loading at all impact velocities less than the optimized velocity, the occupant deceleration was calculated at various velocities for the optimized crash pulse determined at a high speed. The optimized vehicle deceleration-deformation characteristics that are effective for various velocities were investigated with 2 approaches. The optimized vehicle crash pulse at a single impact velocity consists of a high initial impulse followed by zero deceleration and then constant deceleration in the final stage. The vehicle deceleration optimized with the Hybrid III model was comparable to that determined from the spring-mass model. The optimized vehicle deceleration-deformation characteristics determined at a high speed did not necessarily lead to an occupant deceleration reduction at a lower velocity. The maximum occupant deceleration at each velocity was normalized by the maximum deceleration determined in the single impact velocity optimization. The resulting vehicle deceleration-deformation characteristic was a square crash pulse. The objective function was defined as the number of injuries, which was the product of the number of collisions at the velocity and the probability of occupant injury. The optimized vehicle deceleration consisted of a high deceleration in the initial phase, a small deceleration in the middle phase, and then a high deceleration in the final phase. The optimized vehicle crash pulse at a single impact velocity is effective for reducing occupant deceleration in a crash at the specific impact velocity. However, the crash pulse does not necessarily lead to occupant deceleration reduction at a lower velocity. The optimized vehicle deceleration-deformation characteristics, which are effective for all impact velocities, depend on the weighting of the occupant injury measures at each impact velocity.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wenzel, Tom P.
2016-05-20
Previous analyses have indicated that mass reduction is associated with an increase in crash frequency (crashes per VMT), but a decrease in fatality or casualty risk once a crash has occurred, across all types of light-duty vehicles. These results are counter-intuitive: one would expect that lighter, and perhaps smaller, vehicles have better handling and shorter braking distances, and thus should be able to avoid crashes that heavier vehicles cannot. And one would expect that heavier vehicles would have lower risk once a crash has occurred than lighter vehicles. However, these trends occur under several alternative regression model specifications. This reportmore » tests whether these results continue to hold after accounting for crash severity, by excluding crashes that result in relatively minor damage to the vehicle(s) involved in the crash. Excluding non-severe crashes from the initial LBNL Phase 2 and simultaneous two-stage regression models for the most part has little effect on the unexpected relationships observed in the baseline regression models. This finding suggests that other subtle differences in vehicles and/or their drivers, or perhaps biases in the data reported in state crash databases, are causing the unexpected results from the regression models.« less
Chandran, Aruna; Pérez-Núñez, Ricardo; Bachani, Abdulgafoor M; Híjar, Martha; Salinas-Rodríguez, Aarón; Hyder, Adnan A
2014-01-01
In January 2008, a national multifaceted road safety intervention program (IMESEVI) funded by the Bloomberg Philanthropies was launched in Mexico. Two years later in 2010, IMESEVI was refocused as part of a 10-country international consortium demonstration project (IMESEVI/RS10). We evaluate the initial effects of each phase of the road safety intervention project on numbers of RT crashes, injuries and deaths in Mexico and in the two main target cities of Guadalajara-Zapopan and León. An interrupted time series analysis using autoregressive integrated moving average (ARIMA) modeling was performed using monthly data of rates of RT crashes and injuries (police data), as well as deaths (mortality system data) from 1999-2011 with dummy variables representing each intervention phase. In the period following the first intervention phase at the country level and in the city of León, the rate of RT crashes decreased significantly (p<0.05). Notably, following the second intervention phase although there was no reduction at the country level, there has been a decrease in the RT crash rate in both Guadalajara-Zapopan (p = 0.029) and in León (p = 0.029). There were no significant differences in the RT injury or death rates following either intervention phase in either city. These initial results suggest that a multi-faceted road safety intervention program appears to be effective in reducing road crashes in a middle-income country setting. Further analysis is needed to differentiate the effects of various interventions, and to determine what other economic and political factors might have affected this change.
Chandran, Aruna; Pérez-Núñez, Ricardo; Bachani, Abdulgafoor M.; Híjar, Martha; Salinas-Rodríguez, Aarón; Hyder, Adnan A.
2014-01-01
Background In January 2008, a national multifaceted road safety intervention program (IMESEVI) funded by the Bloomberg Philanthropies was launched in Mexico. Two years later in 2010, IMESEVI was refocused as part of a 10-country international consortium demonstration project (IMESEVI/RS10). We evaluate the initial effects of each phase of the road safety intervention project on numbers of RT crashes, injuries and deaths in Mexico and in the two main target cities of Guadalajara-Zapopan and León. Methods An interrupted time series analysis using autoregressive integrated moving average (ARIMA) modeling was performed using monthly data of rates of RT crashes and injuries (police data), as well as deaths (mortality system data) from 1999–2011 with dummy variables representing each intervention phase. Results In the period following the first intervention phase at the country level and in the city of León, the rate of RT crashes decreased significantly (p<0.05). Notably, following the second intervention phase although there was no reduction at the country level, there has been a decrease in the RT crash rate in both Guadalajara-Zapopan (p = 0.029) and in León (p = 0.029). There were no significant differences in the RT injury or death rates following either intervention phase in either city. Conclusion These initial results suggest that a multi-faceted road safety intervention program appears to be effective in reducing road crashes in a middle-income country setting. Further analysis is needed to differentiate the effects of various interventions, and to determine what other economic and political factors might have affected this change. PMID:24498114
U08 : finite element analysis crash model of tractor-trailers (Phase B).
DOT National Transportation Integrated Search
2009-08-01
Improved understanding of truck-infrastructure crashes will enable the highway community to improve barrier design, to further reduce the likelihood of vehicle-infrastructure fatalities and injuries, and to reduce highway congestion resulting from se...
Assessing the risk of crash for trucks on onset yellow.
DOT National Transportation Integrated Search
2012-06-01
Each day, millions of signal changes to the yellow phase occur at isolated high speed intersections, when erroneous : driver decisions to stop or go may often lead to a crash. Dilemma zone protection systems are typically used to control : these inte...
Woitsch, Gernot; Sinz, Wolfgang
2014-01-01
Combination of active and passive safety systems is a future key to further improvement in vehicle safety. Autonomous braking systems are able to reduce collision speeds, and therefore severity levels significantly. Passengers change their position due to pre-impact vehicle motion, a fact, which has not yet been considered in common crash tests. For this paper, finite elements simulations of crash tests were performed to show that forward displacements due to pre-crash braking do not necessarily increase dummy load levels. So the influence of different pre-crash scenarios, all leading to equal closing speeds in the crash phase, are considered in terms of vehicle motion (pitching, deceleration) and restraint system configurations (belt load limiter, pretensioner). The influence is evaluated by dummy loads as well as contact risk between the dummy and the interior. Copyright © 2013 Elsevier Ltd. All rights reserved.
Impact of non-freeway rumble strips phase 1 : appendix III, example of rear end "target" crashes.
DOT National Transportation Integrated Search
2012-06-25
In an effort to reduce lane-departure crashes, in 2008 the Michigan Department of Transportation (MDOT) began a three-year statewide non-freeway rumble strip installation initiative. This initiative called for the installation of milled centerline ru...
Characteristics and Contributory Causes Related to Large Truck Crashes (Phase I) - Fatal Crashes
DOT National Transportation Integrated Search
2010-06-01
One-ninth of all traffic fatalities in the United States have involved large trucks in the past five years, although large trucks contributed to only 3% of registered vehicles and 7% of vehicle miles travelled. This contrasting proportion indicates t...
DOT National Transportation Integrated Search
2012-04-01
This report summarizes a study that seeks to identify the factors leading to the high crash rate experienced on Louisiana highways. Factors were identified by comparing statistics from the Louisiana Crash Database with those from peer states using th...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Xi, P. W.; Lawrence Livermore National Laboratory, Livermore, California 94550; Xu, X. Q.
We demonstrate that the occurrence of Edge-Localized-Modes (ELM) crashes does not depend only on the linear peeling-ballooning threshold, but also relies on nonlinear processes. Wave-wave interaction constrains the growth time of a mode, thus inducing a shift in the criterion for triggering an ELM crash. An ELM crash requires the P-B growth rate to exceed a critical value γ>γ{sub c}, where γ{sub c} is set by 1/τ{sup ¯}{sub c}, and τ{sup ¯}{sub c} is the averaged mode phase coherence time. For 0
DOT National Transportation Integrated Search
2012-06-26
In an effort to reduce lane-departure crashes, in 2008 the Michigan Department of Transportation (MDOT) began a three-year statewide non-freeway rumble strip installation initiative. This initiative called for the installation of milled centerline ru...
DOT National Transportation Integrated Search
1987-07-01
This report details the results of an analysis that compared the Crash Avoidance : Research Data Base (CARDfile) with the National Accident Sampling System (NASS). : CARDfile combines, in one data base, the police accident records for three years : (...
Conversion of the dominantly ideal perturbations into a tearing mode after a sawtooth crash
DOE Office of Scientific and Technical Information (OSTI.GOV)
Igochine, V., E-mail: valentin.igochine@ipp.mpg.de; Gude, A.; Günter, S.
2014-11-15
Forced magnetic reconnection is a topic of common interest in astrophysics, space science, and magnetic fusion research. The tearing mode formation process after sawtooth crashes implies the existence of this type of magnetic reconnection and is investigated in great detail in the ASDEX Upgrade tokamak. The sawtooth crash provides a fast relaxation of the core plasma temperature and can trigger a tearing mode at a neighbouring resonant surface. It is demonstrated for the first time that the sawtooth crash leads to a dominantly ideal kink mode formation at the resonant surface immediately after the sawtooth crash. Local measurements show thatmore » this kink mode transforms into a tearing mode on a much longer timescale (10{sup −3}s−10{sup −2}s) than the sawtooth crash itself (10{sup −4}s). The ideal kink mode formed after the sawtooth crash provides the driving force for magnetic reconnection and its amplitude is one of the critical parameters for the length of the transition phase from a ideal into an resistive mode. Nonlinear two fluid MHD simulations confirm these observations.« less
Modeling left-turn crash occurrence at signalized intersections by conflicting patterns.
Wang, Xuesong; Abdel-Aty, Mohamed
2008-01-01
In order to better understand the underlying crash mechanisms, left-turn crashes occurring at 197 four-legged signalized intersections over 6 years were classified into nine patterns based on vehicle maneuvers and then were assigned to intersection approaches. Crash frequency of each pattern was modeled at the approach level by mainly using Generalized Estimating Equations (GEE) with the Negative Binomial as the link function to account for the correlation among the crash data. GEE with a binomial logit link function was also applied for patterns with fewer crashes. The Cumulative Residuals test shows that, for correlated left-turn crashes, GEE models usually outperformed basic Negative Binomial models. The estimation results show that there are obvious differences in the factors that cause the occurrence of different left-turn collision patterns. For example, for each pattern, the traffic flows to which the colliding vehicles belong are identified to be significant. The width of the crossing distance (represented by the number of through lanes on the opposing approach of the left-turning traffic) is associated with more left-turn traffic colliding with opposing through traffic (Pattern 5), but with less left-turning traffic colliding with near-side crossing through traffic (Pattern 8). The safety effectiveness of the left-turning signal is not consistent for different crash patterns; "protected" phasing is correlated with fewer Pattern 5 crashes, but with more Pattern 8 crashes. The study indicates that in order to develop efficient countermeasures for left-turn crashes and improve safety at signalized intersections, left-turn crashes should be considered in different patterns.
Robertson, L S
1996-01-01
OBJECTIVES. Two phases of attempts to improve passenger car crash worthiness have occurred: minimum safety standards and publicized crash tests. This study evaluated these attempts, as well as changes in seat belt and alcohol use, in terms of their effect on occupant death and fatal crash rates. METHODS. Data on passenger car occupant fatalities and total involvement in fatal crashes, for 1975 through 1991, were obtained from the Fatal Accident Reporting System. Rates per mile were calculated through published sources on vehicle use by vehicle age. Regression estimates of effects of regulation, publicized crash tests, seat belt use and alcohol involvement were obtained. RESULTS. Substantial reductions in fatalities occurred in the vehicle model years from the late 1960s through most of the 1970s, when federal standards were applied. Some additional increments in reduced death rates, attributable to additional improved vehicle crashworthiness, occurred during the period of publicized crash tests. Increased seat belt use and reduced alcohol use also contributed significantly to reduced deaths. CONCLUSIONS. Minimum safety standards, crashworthiness improvements, seat belt use laws, and reduced alcohol use each contributed to a large reduction in passenger car occupant deaths. PMID:8561238
Thermal characterization of QSH crashes in RFX-mod
NASA Astrophysics Data System (ADS)
Fassina, Alessandro; Gobbin, Marco; Franz, Paolo; Marrelli, Lionello; Ruzzon, Alberto
2012-10-01
QSH (Quasi Single Helicity) states have gained a growing interest in RFP research since they show improved confinement and transport features with respect to standard discharges. However, ITBs associated with QSH states can be obtained only in a transient way, and in general with a shorter lifetime with respect to that of the QSH phase [1]. In this work the analysis has essentially the purpose of confirming, with TS data, the Te dynamics seen with the double filter, multichord SXR spectrometer in [1]: TS data allow a better spatial definition of temperature profile and a more reliable description of plasma edge. Te profile features in rising and crashing phases are determined via ensemble averaging, possible precursors of thermal crashes are identified, while q(r) behavior is studied identifying the thermal structures associated with rational surfaces. [4pt] [1] Ruzzon et al, 39th EPS Conference, P2.023
Fell, James C.; Jones, Kristina; Romano, Eduardo; Voas, Robert
2013-01-01
Objective Graduated driver licensing (GDL) systems are designed to reduce the high crash risk of young novice drivers. Almost all states in the United States have some form of a three-phased GDL system with various restrictions in the intermediate phase. Studies of the effects of GDL in various states show significant reductions in fatal crash involvements of 16- and 17-year-old drivers; however, only a few national studies of GDL effects have been published. The objective of this national panel study was to evaluate the effect of GDL laws on the fatal crash involvements of novice drivers while controlling for possible confounding factors not accounted for in prior studies. Methods The Fatality Analysis Reporting System (FARS) was used to examine 16- and 17-year-old driver involvement in fatal crashes (where GDL laws are applied) relative to two young driver age groups (19-20, 21-25) where GDL would not be expected to have an effect. Dates when various GDL laws were adopted in the states between 1990 and 2007 were coded from a variety of sources. Covariates in the longitudinal panel regression analyses conducted included four laws that could have an effect on 16- and 17-year-old drivers: primary enforcement seat belt laws, zero-tolerance (ZT) alcohol laws for drivers younger than age 21, lowering the blood alcohol concentration limit for driving to .08, and so-called “use and lose” laws where drivers aged 20 and younger lose their licenses for underage drinking violations. Results The adoption of a GDL law of average strength was associated with a significant decrease in fatal crash involvements of 16- and 17-year-old drivers relative to fatal crash involvements of one of the two comparison groups. GDL laws rated as “good” showed stronger relationships to fatal crash reductions, and laws rated as “less than good” showed no reductions in crash involvements relative to the older driver comparison groups. Conclusions States that adopt a basic GDL law can expect a decrease of 8 to 14% in the proportion of 16- and 17-year-old drivers involved in fatal crashes (relative to 21- to 25-year-old drivers), depending upon their other existing laws that affect novice drivers, such as those used in these analyses. This finding is consistent with recent national studies that used different outcome measures and covariates. The results of this study provide additional support for states to adopt, maintain, and upgrade GDL systems to reduce youthful traffic crash fatalities. PMID:21972851
Human factors in aviation crashes involving older pilots.
Li, Guohua; Baker, Susan P; Lamb, Margaret W; Grabowski, Jurek G; Rebok, George W
2002-02-01
Pilot errors are recognized as a contributing factor in as many as 80% of aviation crashes. Experimental studies using flight simulators indicate that due to decreased working memory capacity, older pilots are outperformed by their younger counterparts in communication tasks and flight summary scores. This study examines age-related differences in crash circumstances and pilot errors in a sample of pilots who flew commuter aircraft or air taxis and who were involved in airplane or helicopter crashes. A historical cohort of 3306 pilots who in 1987 flew commuter aircraft or air taxis and were 45-54 yr of age was constructed using the Federal Aviation Administration's airmen information system. Crash records of the study subjects for the years 1983-1997 were obtained from the National Transportation Safety Board (NTSB) by matching name and date of birth. NTSB's investigation reports were reviewed to identify pilot errors and other contributing factors. Comparisons of crash circumstances and human factors were made between pilots aged 40-49 yr and pilots aged 50-63 yr. A total of 165 crash records were studied, with 52% of these crashes involving pilots aged 50-63 yr. Crash circumstances, such as time and location of crash, type and phase of flight, and weather conditions, were similar between the two age groups. Pilot error was a contributing factor in 73% of the crashes involving younger pilots and in 69% of the crashes involving older pilots (p = 0.50). Age-related differences in the pattern of pilot errors were statistically insignificant. Overall, 23% of pilot errors were attributable to inattentiveness, 20% to flawed decisions, 18% to mishandled aircraft kinetics, and 18% to mishandled wind/runway conditions. Neither crash circumstances nor the prevalence and patterns of pilot errors appear to change significantly as age increases from the 40s to the 50s and early 60s.
Development of a highway incident management operational and training guide : phase II.
DOT National Transportation Integrated Search
2014-08-01
The overall goal of both phases of this project was to reduce responder fatalities and injuries, as well as to prevent : secondary crashes, especially those involving incident responders. The phases of this project worked toward this goal : by creati...
Xu, Chengcheng; Wang, Wei; Liu, Pan; Zhang, Fangwei
2015-01-01
This study aimed to identify the traffic flow variables contributing to crash risks under different traffic states and to develop a real-time crash risk model incorporating the varying crash mechanisms across different traffic states. The crash, traffic, and geometric data were collected on the I-880N freeway in California in 2008 and 2009. This study considered 4 different traffic states in Wu's 4-phase traffic theory. They are free fluid traffic, bunched fluid traffic, bunched congested traffic, and standing congested traffic. Several different statistical methods were used to accomplish the research objective. The preliminary analysis showed that traffic states significantly affected crash likelihood, collision type, and injury severity. Nonlinear canonical correlation analysis (NLCCA) was conducted to identify the underlying phenomena that made certain traffic states more hazardous than others. The results suggested that different traffic states were associated with various collision types and injury severities. The matching of traffic flow characteristics and crash characteristics in NLCCA revealed how traffic states affected traffic safety. The logistic regression analyses showed that the factors contributing to crash risks were quite different across various traffic states. To incorporate the varying crash mechanisms across different traffic states, random parameters logistic regression was used to develop a real-time crash risk model. Bayesian inference based on Markov chain Monte Carlo simulations was used for model estimation. The parameters of traffic flow variables in the model were allowed to vary across different traffic states. Compared with the standard logistic regression model, the proposed model significantly improved the goodness-of-fit and predictive performance. These results can promote a better understanding of the relationship between traffic flow characteristics and crash risks, which is valuable knowledge in the pursuit of improving traffic safety on freeways through the use of dynamic safety management systems.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wenzel, Tom P.
The Department of Energy’s (DOE) Vehicle Technologies Office funds research on development of technologies to improve the fuel economy of both light- and heavy-duty vehicles, including advanced combustion systems, improved batteries and electric drive systems, and new lightweight materials. Of these approaches to increase fuel economy and reduce fuel consumption, reducing vehicle mass through more extensive use of strong lightweight materials is perhaps the easiest and least expensive method; however, there is a concern that reducing vehicle mass may lead to more fatalities. Lawrence Berkeley National Laboratory (LBNL) has conducted several analyses to better understand the relationship between vehicle mass,more » size and safety, in order to ameliorate concerns that down-weighting vehicles will inherently lead to more fatalities. These analyses include recreating the regression analyses conducted by the National Highway Traffic Safety Administration (NHTSA) that estimate the relationship between mass reduction and U.S. societal fatality risk per vehicle mile of travel (VMT), while holding vehicle size (i.e. footprint, wheelbase times track width) constant; these analyses are referred to as LBNL Phase 1 analysis. In addition, LBNL has conducted additional analysis of the relationship between mass and the two components of risk per VMT, crash frequency (crashes per VMT) and risk once a crash has occurred (risk per crash); these analyses are referred to as LBNL Phase 2 analysis.« less
Economic Sanctions, Military Activity, and Road Traffic Crashes in Vojvodina, Serbia
Ðurić, Predrag; Peek-Asa, Corinne
2008-01-01
Objectives Political violence has not been examined as a risk factor for traumatic injuries from road traffic crashes. We identify trends in road traffic crashes related to war-related military activity and international economic sanctions in the Autonomous Province of Vojvodina, Serbia. Methods Overall road traffic crashes and crashes leading to hospitalization and fatality in Vojvodina, Serbia were examined from 1996 through 2001. Rates were calculated per 100,000 population and per 10,000 registered vehicles. Three time periods were examined: years with international sanctions and military activity; years with international sanctions but no military activity; and, years with neither sanctions nor military activity. Results Compared to the period with neither sanctions nor military activity, severe injury crashes were 1.23 times more frequent (95% CI = 1.19 – 1.27) during the period with sanctions and military activity and 1.21 times more frequent (95% CI= 1.16 – 1.27) during the period with sanctions but no military activity. Conclusions Our data suggest that vehicle travel became safer following the end of military action and economic sanctions. Road traffic safety needs to be a priority both during periods of political unrest and its recovery phase. PMID:19074242
DOT National Transportation Integrated Search
2009-03-01
This project was initiated in the fall of 1999. The results through the fall of 2005 (Phase I) have been documented in detail in an earlier report. The accomplishments of Phase I included the following: the identification of existing animal detection...
Impact of inward turbulence spreading on energy loss of edge-localized modes
Ma, C. H.; Xu, X. Q.; Xi, P. W.; ...
2015-05-18
Nonlinear two-fluid and gyrofluid simulations show that an edge localized modes(ELM) crash has two phases: fast initial crash of ion temperature perturbation on the Alfvén time scale and slow turbulence spreading. The turbulencetransport phase is a slow encroachment of electron temperature perturbation due to the ELM event into pedestal region. Because of the inward turbulence spreading effect, the energy loss of an ELM decreases when density pedestal height increases. The Landau resonance yields the different cross phase-shift of ions and electrons. A 3 + 1 gyro-Landau-fluid model is implemented in BOUT++ framework. As a result, the gyrofluid simulations show thatmore » the kinetic effects have stabilizing effects on the ideal ballooning mode and the energy loss increases with the pedestal height.« less
Kim, Taewung; Bose, Dipan; Foster, Jon; Bollapragada, Varun; Crandall, Jeff R; Clauser, Mark; Kerrigan, Jason R
2017-10-01
This study aimed to identify common patterns of pre-ballistic vehicle kinematics and roadway characteristics of real-world rollover crashes. Rollover crashes that were enrolled in the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS) between the years 2000 and 2010 were analyzed. A descriptive analysis was performed to understand the characteristics of the pre-ballistic phase. Also, a frequency based pattern analysis was performed using a selection of NASS-CDS variables describing the pre-ballistic vehicle kinematics and roadway characteristics to rank common pathways of rollover crashes. Most case vehicles departed the road due to a loss of control/traction (LOC) (61%). The road departure with LOC was found to be 13.4 times more likely to occur with slippery road conditions compared to dry conditions. The vehicle was typically laterally skidding with yawing prior to a rollover (66%). Most case vehicles tripped over (82%) mostly at roadside/median (69%). The tripping force was applied to the wheels/tires (82%) from the ground (79%). The combination of these six most frequent attributes resulted in the most common scenario, which accounted for 26% of the entire cases. Large proportion of road departure with LOC (61%) implies electronic stability control (ESC) systems being an effective countermeasure for preventing single-vehicle rollover crashes. Furthermore, the correlation between the road departure with LOC and the reduced friction limit suggests the necessity of the performance evaluation of ESC under compromised road surface condition. Copyright © 2017 Elsevier Ltd. All rights reserved.
Montella, Alfonso; Chiaradonna, Salvatore; Criscuolo, Giorgio; De Martino, Salvatore
2017-02-05
First step of the development of an effective safety management system is to create reliable crash databases since the quality of decision making in road safety depends on the quality of the data on which decisions are based. Improving crash data is a worldwide priority, as highlighted in the Global Plan for the Decade of Action for Road Safety adopted by the United Nations, which recognizes that the overall goal of the plan will be attained improving the quality of data collection at the national, regional and global levels. Crash databases provide the basic information for effective highway safety efforts at any level of government, but lack of uniformity among countries and among the different jurisdictions in the same country is observed. Several existing databases show significant drawbacks which hinder their effective use for safety analysis and improvement. Furthermore, modern technologies offer great potential for significant improvements of existing methods and procedures for crash data collection, processing and analysis. To address these issues, in this paper we present the development and evaluation of a web-based platform-independent software for crash data collection, processing and analysis. The software is designed for mobile and desktop electronic devices and enables a guided and automated drafting of the crash report, assisting police officers both on-site and in the office. The software development was based both on the detailed critical review of existing Australasian, EU, and U.S. crash databases and software as well as on the continuous consultation with the stakeholders. The evaluation was carried out comparing the completeness, timeliness, and accuracy of crash data before and after the use of the software in the city of Vico Equense, in south of Italy showing significant advantages. The amount of collected information increased from 82 variables to 268 variables, i.e., a 227% increase. The time saving was more than one hour per crash, i.e., a 36% reduction. The on-site data collection did not produce time saving, however this is a temporary weakness that will be annihilated very soon in the future after officers are more acquainted with the software. The phase of evaluation, processing and analysis carried out in the office was dramatically shortened, i.e., a 69% reduction. Another benefit was the standardization which allowed fast and consistent data analysis and evaluation. Even if all these benefits are remarkable, the most valuable benefit of the new procedure was the reduction of the police officers mistakes during the manual operations of survey and data evaluation. Because of these benefits, the satisfaction questionnaires administrated to the police officers after the testing phase showed very good acceptance of the procedure. Copyright © 2017 Elsevier Ltd. All rights reserved.
Roadway lighting and safety : phase II--monitoring quality, durability and efficiency.
DOT National Transportation Integrated Search
2011-10-01
This Phase II project follows a previous project titled Strategies to Address Nighttime Crashes at Rural, Unsignalized Intersections. Based on the results of the previous study, the Iowa Highway Research Board (IHRB) indicated interest in pursuing fu...
Small car exposure data project. Phase 1 : methodology
DOT National Transportation Integrated Search
1985-10-01
The Small Car Exposure Data Project represents the first phase of an effort to build a data : base of exposure variables for crash-avoidance studies. Among these are: (1) vehicle make, : model, year, body style, wheel base, weight, and horsepower; (2...
GIS-based accident location and analysis system (GIS-ALAS) : project report : phase I
DOT National Transportation Integrated Search
1998-04-06
This report summarizes progress made in Phase I of the geographic information system (GIS) based Accident Location and Analysis System (GIS-ALAS). The GIS-ALAS project builds on PC-ALAS, a locationally-referenced highway crash database query system d...
Bates, Lyndel J.; Allen, Siobhan; Armstrong, Kerry; Watson, Barry; King, Mark J.; Davey, Jeremy
2014-01-01
Graduated driver licensing (GDL) aims to gradually increase the exposure of new drivers to more complex driving situations and typically consists of learner, provisional and open licence phases. The first phase, the learner licence, is designed to allow novice drivers to obtain practical driving experience in lower risk situations. The learner licence can delay licensure, encourage novice drivers to learn under supervision, mandate the number of hours of practice required to progress to the next phase and encourage parental involvement. The second phase, the provisional licence, establishes various driving restrictions and thereby reduces exposure to situations of higher risk, such as driving at night, with passengers or after drinking alcohol. Parental involvement with a GDL system appears essential in helping novices obtain sufficient practice and in enforcing compliance with restrictions once the new driver obtains a provisional licence. Given the significant number of young drivers involved in crashes within Oman, GDL is one countermeasure that may be beneficial in reducing crash risk and involvement for this group. PMID:25364543
Pruchnicki, Shawn A; Wu, Lora J; Belenky, Gregory
2011-05-01
On 27 August 2006 at 0606 eastern daylight time (EDT) at Bluegrass Airport in Lexington, KY (LEX), the flight crew of Comair Flight 5191 inadvertently attempted to take off from a general aviation runway too short for their aircraft. The aircraft crashed killing 49 of the 50 people on board. To better understand this accident and to aid in preventing similar accidents, we applied mathematical modeling predicting fatigue-related degradation in performance for the Air Traffic Controller on-duty at the time of the crash. To provide the necessary input to the model, we attempted to estimate circadian phase and sleep/wake histories for the Captain, First Officer, and Air Traffic Controller. We were able to estimate with confidence the circadian phase for each. We were able to estimate with confidence the sleep/wake history for the Air Traffic Controller, but unable to do this for the Captain and First Officer. Using the sleep/wake history estimates for the Air Traffic Controller as input, the mathematical modeling predicted moderate fatigue-related performance degradation at the time of the crash. This prediction was supported by the presence of what appeared to be fatigue-related behaviors in the Air Traffic Controller during the 30 min prior to and in the minutes after the crash. Our modeling results do not definitively establish fatigue in the Air Traffic Controller as a cause of the accident, rather they suggest that had he been less fatigued he might have detected Comair Flight 5191's lining up on the wrong runway. We were not able to perform a similar analysis for the Captain and First Officer because we were not able to estimate with confidence their sleep/wake histories. Our estimates of sleep/wake history and circadian rhythm phase for the Air Traffic Controller might generalize to other air traffic controllers and to flight crew operating in the early morning hours at LEX. Relative to other times of day, the modeling results suggest an elevated risk of fatigue-related error, incident, or accident in the early morning due to truncated sleep from the early start and adverse circadian phase from the time of day. This in turn suggests that fatigue mitigation targeted to early morning starts might reduce fatigue risk. In summary, this study suggests that mathematical models predicting performance from sleep/wake history and circadian phase are (1) useful in retrospective accident analysis provided reliable sleep/wake histories are available for the accident personnel and, (2) useful in prospective fatigue-risk identification, mitigation, and accident prevention. Copyright © 2010 Elsevier Ltd. All rights reserved.
Gaewsky, James P; Weaver, Ashley A; Koya, Bharath; Stitzel, Joel D
2015-01-01
A 3-phase real-world motor vehicle crash (MVC) reconstruction method was developed to analyze injury variability as a function of precrash occupant position for 2 full-frontal Crash Injury Research and Engineering Network (CIREN) cases. Phase I: A finite element (FE) simplified vehicle model (SVM) was developed and tuned to mimic the frontal crash characteristics of the CIREN case vehicle (Camry or Cobalt) using frontal New Car Assessment Program (NCAP) crash test data. Phase II: The Toyota HUman Model for Safety (THUMS) v4.01 was positioned in 120 precrash configurations per case within the SVM. Five occupant positioning variables were varied using a Latin hypercube design of experiments: seat track position, seat back angle, D-ring height, steering column angle, and steering column telescoping position. An additional baseline simulation was performed that aimed to match the precrash occupant position documented in CIREN for each case. Phase III: FE simulations were then performed using kinematic boundary conditions from each vehicle's event data recorder (EDR). HIC15, combined thoracic index (CTI), femur forces, and strain-based injury metrics in the lung and lumbar vertebrae were evaluated to predict injury. Tuning the SVM to specific vehicle models resulted in close matches between simulated and test injury metric data, allowing the tuned SVM to be used in each case reconstruction with EDR-derived boundary conditions. Simulations with the most rearward seats and reclined seat backs had the greatest HIC15, head injury risk, CTI, and chest injury risk. Calculated injury risks for the head, chest, and femur closely correlated to the CIREN occupant injury patterns. CTI in the Camry case yielded a 54% probability of Abbreviated Injury Scale (AIS) 2+ chest injury in the baseline case simulation and ranged from 34 to 88% (mean = 61%) risk in the least and most dangerous occupant positions. The greater than 50% probability was consistent with the case occupant's AIS 2 hemomediastinum. Stress-based metrics were used to predict injury to the lower leg of the Camry case occupant. The regional-level injury metrics evaluated for the Cobalt case occupant indicated a low risk of injury; however, strain-based injury metrics better predicted pulmonary contusion. Approximately 49% of the Cobalt occupant's left lung was contused, though the baseline simulation predicted 40.5% of the lung to be injured. A method to compute injury metrics and risks as functions of precrash occupant position was developed and applied to 2 CIREN MVC FE reconstructions. The reconstruction process allows for quantification of the sensitivity and uncertainty of the injury risk predictions based on occupant position to further understand important factors that lead to more severe MVC injuries.
Evaluation of an autonomous braking system in real-world PTW crashes.
Savino, Giovanni; Pierini, Marco; Rizzi, Matteo; Frampton, Richard
2013-01-01
Powered 2-wheelers (PTWs) are becoming increasingly popular in Europe. They have the ability to get around traffic queues, thus lowering fuel consumption and increasing mobility. The risk of rider injury in a traffic crash is however much higher than that associated with car users. The European project, Powered Two Wheeler Integrated Safety (PISa), identified an autonomous braking system (AB) as a priority to reduce the injury consequences of a PTW crash. The aim of this study was to assess the potential effectiveness of the AB system developed in PISa, taking into account the specific system characteristics that emerged during the design, development and testing phases. Fifty-eight PTW cases representing European crash configurations were examined, in which 43 percent of riders sustained a Maximum Abbreviated Injury Scale (MAIS) 2+ injury. Two of the most common crash types were a PTW impacting a stationary object (car following scenario) 16% and an object pulling across the PTW path (crossing scenario) 54%. An expert team analysed the in-depth material of the sample crashes and determined a posteriori to what extent the AB would have affected the crash. For those cases where the AB was evaluated as applicable, a further quantitative evaluation of the benefits was conducted by considering a set of different possible rider reactions in addition to that exhibited in the actual crash. In 67 percent of cases, the application of AB could have mitigated the crash outcome. Analysis of those real crash cases showed the potential for an expert rider to avoid the collision. An early reaction of the rider, associated with a correct application of the brakes would have avoided 18 of the 37 car following/crossing scenarios. Conversely, according to the analysis, an expert rider would not have been able to avoid 19 of the 37 cases. In 14 of those 19 cases, the AB would have contributed to mitigating the crash outcome. This study demonstrated significant potential for application of the autonomous braking system in car following and crossing scenarios. In addition, the theoretical benefit curves for the AB globally, were able to provide good quantitative indications of its benefits in real cases where the AB was considered applicable. Further analysis with larger databases is suggested in order to confirm the magnitude of benefits in the PTW crash population.
Strandroth, Johan; Rizzi, Matteo; Olai, Maria; Lie, Anders; Tingvall, Claes
2012-03-01
This study set out to examine the effects of studded tires on fatal crashes on roads covered with ice or snow in Sweden and also to investigate the extra benefits of electronic stability control (ESC) during the winter months. Two different studies are presented in this paper. Both studies used an induced exposure approach. In the main study, 369 in-depth studies of fatal crashes with passenger cars were analyzed to determine whether loss-of-control (LOC) had been a major component or not. Only crashes involving cars without ESC and equipped with approved studded or non-studded winter tires were analyzed. The additional study used police-reported crashes that occurred during the winter seasons 2003-2010, involving passenger cars with and without ESC. While police records in Sweden do not include any tire information, it was assumed that most cars involved in crashes during the winter period would be equipped with studded tires. Findings in the main study showed that in 64% of the fatal crashes on roads covered with ice or snow LOC had been a major component. Furthermore, in 82% of LOC crashes, the passenger car over-steered prior to collision. Studded tires were found to have a statistically significant effect of 42% in terms of fatal crash reduction on roads covered with ice or snow, compared to non-studded winter tires. The effect on dry or wet roads in the winter was negative, although statistically non-significant. In the additional study, it was found that ESC further reduced crashes with injuries by 29%. The benefits on severe and fatal crashes were slightly greater (32%), although the lower 95% confidence limit was lower. Although studded tires were shown to reduce the risk of fatal crash involvement, compared to non-studded winter tires, the proportion of LOC and over-steering among cars with studded tires was large (59% and 49%, respectively). It was therefore concluded that studded tires do not prevent all LOC crashes, while ESC has benefits in those crashes since this technology mostly addresses over-steering. This is also supported by the fact that the share of LOC fatal crashes is considerably lower for ESC-equipped cars. This study recommends that non-ESC cars should be fitted with studded tires if they are to be driven on roads covered by ice or snow. If the proportion of studded tires is to be decreased on Swedish roads to reduce the about of hazardous particulates especially in built up areas, from a road safety point of view it is recommended that this should be done in phase with the implementation of ESC on all passenger cars. Copyright © 2011 Elsevier Ltd. All rights reserved.
Viano, David C; Parenteau, Chantal S
2016-04-01
This study investigated the change in the fatality and severe injury risks in rear impacts with vehicle model years (MY) grouped prior to, during the phase-in and after the revision to FMVSS 301. FARS and NASS-CDS data were used to determine the injury risks of non-ejected occupants in light vehicles involving non-rollover, rear impacts. The data were analyzed by MY groups: 1996-2001, 2002-2007 and 2008+ to represent the years prior to, during the phase-in and post-revision phase-in of FMVSS 301. The 1996-2013 FARS data were analyzed for rear crashes defined by the initial crash direction (IMPACT1) and direction with most damage (IMPACT2) to the rear. Fatality risk was determined by the number of fatally injured occupants per all occupants with known injury status. The 1994-2013 NASS-CDS was analyzed for rear crashes defined by the damage area variable. The risk of severe injury (MAIS 4+F) was determined as the number of occupants with MAIS 4+F injury per all occupants with known injury status. The distribution of rear crashes was determined by impact location and crash severity. NASS-CDS electronic cases with 2008+ MY vehicles were analyzed to evaluate the vehicle and occupant performance. The fatality risk was 20.6% in the 1996-2001, 17.3% in the 2002-2007 and 15.0% in the 2008+ MY vehicles using FARS with the initial crash direction variable (IMPACT1) to the rear. There was a 27.1% reduction in risk with post-FMVSS 301 vehicles 2008+ MY. The risk was 19.0%, 15.4% and 12.8% with the most damage variable (IMPACT2) to the rear. There was 32.8% reduction in risk with 2008+ MY vehicles. The NASS-CDS analysis showed that the risk of severe injury (MAIS 4+F) was 0.27±0.05% for 1996-2001, 0.30±0.13% for 2002-2007 and 0.08±0.04% for 2008+ MY year vehicles. There was a 70.2% reduction in the risk for severe injury with 2008+ MY vehicles. The NASS-CDS case review of MAIS 4+F injury in rear impacts of 2008+ MY vehicles that comply with the revised FMVSS 301 indicated that the crashes were very severe and generally involved significant 2nd row intrusion. The revision to FMVSS 301 has effectively reduced the risks for fatal and severe injury in vehicles compliant with the revision (2008+ MY). The reduction was 27.1-32.8% in fatality risk using FARS data and 70.2% in severe injury risk using the NASS-CDS when compared to vehicles prior to the phase-in of the revised FMVSS 301 (1996-2001 MY vehicles). It is not possible to parse the effects of other design changes in seats and restraint systems that also increased safety over the study years. Copyright © 2015 Elsevier Ltd. All rights reserved.
A new analysis of the effects of the Asian crisis of 1997 on emergent markets
NASA Astrophysics Data System (ADS)
Mariani, M. C.; Liu, Y.
2007-07-01
This work is devoted to the study of the Asian crisis of 1997, and its consequences on emerging markets. We have done so by means of a phase transition model. We have analyzed the crashes on leading indices of Hong Kong (HSI), Turkey (XU100), Mexico (MMX), Brazil (BOVESPA) and Argentina (MERVAL). We were able to obtain optimum values for the critical date, corresponding to the most probable date of the crash. The estimation of the critical date was excellent except for the MERVAL index; this improvement is due to a previous analysis of the parameters involved. We only used data from before the true crash date in order to obtain the predicted critical date. This article's conclusions are largely obtained via ad hoc empirical methods.
DOT National Transportation Integrated Search
2015-06-01
The objective of this project was to develop guidelines for time-of-day use of permitted left-turn phasing, : which can then be implemented using flashing yellow arrows (FYA). This required determining how the risk : for left-turn crashes varied as t...
NASA Astrophysics Data System (ADS)
Grech, Dariusz
We define and confront global and local methods to analyze the financial crash-like events on the financial markets from the critical phenomena point of view. These methods are based respectively on the analysis of log-periodicity and on the local fractal properties of financial time series in the vicinity of phase transitions (crashes). The log-periodicity analysis is made in a daily time horizon, for the whole history (1991-2008) of Warsaw Stock Exchange Index (WIG) connected with the largest developing financial market in Europe. We find that crash-like events on the Polish financial market are described better by the log-divergent price model decorated with log-periodic behavior than by the power-law-divergent price model usually discussed in log-periodic scenarios for developed markets. Predictions coming from log-periodicity scenario are verified for all main crashes that took place in WIG history. It is argued that crash predictions within log-periodicity model strongly depend on the amount of data taken to make a fit and therefore are likely to contain huge inaccuracies. Next, this global analysis is confronted with the local fractal description. To do so, we provide calculation of the so-called local (time dependent) Hurst exponent H loc for the WIG time series and for main US stock market indices like DJIA and S&P 500. We point out dependence between the behavior of the local fractal properties of financial time series and the crashes appearance on the financial markets. We conclude that local fractal method seems to work better than the global approach - both for developing and developed markets. The very recent situation on the market, particularly related to the Fed intervention in September 2007 and the situation immediately afterwards is also analyzed within fractal approach. It is shown in this context how the financial market evolves through different phases of fractional Brownian motion. Finally, the current situation on American market is analyzed in fractal language. This is to show how far we still are from the end of recession and from the beginning of a new boom on US financial market or on other world leading stocks.
1988-08-01
the crash of Delta Flight 191 in the summer of 1985, the Dallas community was faced with the awful reality of a mass casualty disaster. At that time...accident free aviation; air crashes appear to be an evil and seemingly inevitable reality . Airports involved in air carrier operations are required to...hours. (3) Retrieval Phase. At this point, the victim becomes aware that the end of his ordeal is in fact a reality and perhaps here is when the guard
Montella, Alfonso
2011-07-01
The use of roundabouts improves intersection safety by eliminating or altering conflict types, reducing crash severity, and causing drivers to reduce speeds. However, roundabout performances can degrade if precautions are not taken during either the design or the operation phase. Therefore, additional information on the safety of the roundabouts is extremely helpful for planners and designers in identifying existing deficiencies and in refining the design criteria currently being used. The aim of the paper was to investigate the crash contributory factors in 15 urban roundabouts located in Italy and to study the interdependences between these factors. The crash data refer to the period 2003-2008. The identification of the crash contributory factors was based on site inspections and rigorous analyses performed by a team of specialists with a relevant road safety engineering background. Each roundabout was inspected once every year from 2004 to 2009, both in daytime and in nighttime. Overall, 62 different contributory factors and 2156 total contributory factors were identified. In 51 crashes, a single contributory factor was found, whereas in the other 223 crashes, a combination of contributory factors was identified. Given the large amount of data, the interdependences between the contributory factors and between the contributory factors and the different crash types were explored by an association discovery. Association discovery is the identification of sets of items (i.e., crash contributory factors and crash types in our study) that occur together in a given event (i.e., a crash in our study). The rules were filtered by support, confidence, and lift. As a result, 112 association rules were discovered. Overall, numerous contributory factors related to the road and environment deficiencies but not related to the road user or to the vehicle were identified. The most important factors related to geometric design were the radius of deflection and the deviation angle. In existing roundabouts, the improvement of these factors might be quite expensive, but the crucial role of a moderate radius of deflection and a large deviation angle in the design of new roundabouts was stressed. Many of the contributory factors were related to markings and signs, and these factors could be easily removed with low-cost safety measures. Furthermore, because of the association between the markings, signs, and geometric design contributory factors, the study results suggest that the improvement in markings and signs might also have a significant effect in the sites where geometric design deficiencies were identified as contributory factors. Copyright © 2011 Elsevier Ltd. All rights reserved.
The non-resonant kink modes triggering strong sawtooth-like crashes in the EAST tokamak
NASA Astrophysics Data System (ADS)
Li, Erzhong; Igochine, V.; Dumbrajs, O.; Xu, L.; Chen, K.; Shi, T.; Hu, L.
2014-12-01
Evolution of the safety factor (q) profile during L-H transitions in the Experimental Advanced Superconducting Tokamak (EAST) was accompanied by strong core crashes prior to regular sawtooth behavior. These crashes appeared in the absence of q = 1 (q is the safety factor) rational surface inside the plasma. Analysis indicates that the m/n = 2/1 tearing mode is destabilized and phase-locked with the m/n = 1/1 non-resonant kink mode (the q = 1 rational surface is absent) due to the self-consistent evolution of plasma profiles as the L-H transition occurs (m and n are the poloidal and toroidal mode numbers, respectively). The growing m/n = 1/1 mode destabilizes the m/n = 2/2 kink mode which eventually triggers the strong crash due to an anomalous heat conductivity, as predicted by the transport model of stochastic magnetic fields using experimental parameters. It is also shown that the magnetic topology changes with the amplitude of m/n = 2/2 mode and the value of center safety factor in a reasonable range.
Bumper and grille airbags concept for enhanced vehicle compatibility in side impact: phase II.
Barbat, Saeed; Li, Xiaowei; Prasad, Priya
2013-01-01
Fundamental physics and numerous field studies have shown a higher injury and fatality risk for occupants in smaller and lighter vehicles when struck by heavier, taller and higher vehicles. The consensus is that the significant parameters influencing compatibility in front-to-side crashes are geometric interaction, vehicle stiffness, and vehicle mass. The objective of this research is to develop a concept of deployable bumper and grille airbags for improved vehicle compatibility in side impact. The external airbags, deployed upon signals from sensors, may help mitigate the effect of weight, geometry and stiffness differences and reduce side intrusions. However, a highly reliable pre-crash sensing system is required to enable the reliable deployment, which is currently not technologically feasible. Analytical and numerical methods and hardware testing were used to help develop the deployable external airbags concept. Various Finite Element (FE) models at different stages were developed and an extensive number of iterations were conducted to help optimize airbag and inflator parameters to achieve desired targets. The concept development was executed and validated in two phases. This paper covers Phase II ONLY, which includes: (1) Re-design of the airbag geometry, pressure, and deployment strategies; (2) Further validation using a Via sled test of a 48 kph perpendicular side impact of an SUV-type impactor against a stationary car with US-SID-H3 crash dummy in the struck side; (3) Design of the reaction surface necessary for the bumper airbag functionality. The concept was demonstrated through live deployment of external airbags with a reaction surface in a full-scale perpendicular side impact of an SUV against a stationary passenger car at 48 kph. This research investigated only the concept of the inflatable devices since pre-crash sensing development was beyond the scope of this research. The concept design parameters of the bumper and grille airbags are presented in this paper. Full vehicle-to-vehicle crash test results, Via sled test, and simulation results are also presented. Head peak acceleration, Head Injury Criteria (HIC), Thoracic Trauma Index (TTI), and Pelvic acceleration for the SID-H3 dummy and structural intrusion profiles were used as performance metrics for the bumper and grille airbags. Results obtained from the Via sled tests and the full vehicle-to-vehicle tests with bumper and grille airbags were compared to those of baseline test results with no external airbags.
NASA Astrophysics Data System (ADS)
Czarnecki, Łukasz; Grech, Dariusz; Pamuła, Grzegorz
2008-12-01
We confront global and local methods to analyze the financial crash-like events on the Polish financial market from the critical phenomena point of view. These methods are based on the analysis of log-periodicity and the local fractal properties of financial time series in the vicinity of phase transitions (crashes). The whole history (1991-2008) of Warsaw Stock Exchange Index (WIG) describing the largest developing financial market in Europe, is analyzed in a daily time horizon. We find that crash-like events on the Polish financial market are described better by the log-divergent price model decorated with log-periodic behavior than the corresponding power-law-divergent price model. Predictions coming from log-periodicity scenario are verified for all main crashes that took place in WIG history. It is argued that crash predictions within log-periodicity model strongly depend on the amount of data taken to make a fit and therefore are likely to contain huge inaccuracies. Turning to local fractal description, we calculate the so-called local (time dependent) Hurst exponent H for the WIG time series and we find the dependence between the behavior of the local fractal properties of the WIG time series and the crashes appearance on the financial market. The latter method seems to work better than the global approach - both for developing as for developed markets. The current situation on the market, particularly related to the Fed intervention in September’07 and the situation on the market immediately after this intervention is also analyzed from the fractional Brownian motion point of view.
Chen, Yikai; Wang, Kai; Xu, Chengcheng; Shi, Qin; He, Jie; Li, Peiqing; Shi, Ting
2018-05-19
To overcome the limitations of previous highway alignment safety evaluation methods, this article presents a highway alignment safety evaluation method based on fault tree analysis (FTA) and the characteristics of vehicle safety boundaries, within the framework of dynamic modeling of the driver-vehicle-road system. Approaches for categorizing the vehicle failure modes while driving on highways and the corresponding safety boundaries were comprehensively investigated based on vehicle system dynamics theory. Then, an overall crash probability model was formulated based on FTA considering the risks of 3 failure modes: losing steering capability, losing track-holding capability, and rear-end collision. The proposed method was implemented on a highway segment between Bengbu and Nanjing in China. A driver-vehicle-road multibody dynamics model was developed based on the 3D alignments of the Bengbu to Nanjing section of Ning-Luo expressway using Carsim, and the dynamics indices, such as sideslip angle and, yaw rate were obtained. Then, the average crash probability of each road section was calculated with a fixed-length method. Finally, the average crash probability was validated against the crash frequency per kilometer to demonstrate the accuracy of the proposed method. The results of the regression analysis and correlation analysis indicated good consistency between the results of the safety evaluation and the crash data and that it outperformed the safety evaluation methods used in previous studies. The proposed method has the potential to be used in practical engineering applications to identify crash-prone locations and alignment deficiencies on highways in the planning and design phases, as well as those in service.
Williams, A F
1997-01-01
Teenage drivers in the United States have greatly elevated crash rates, primarily a result of qualities associated with immaturity and lack of driving experience. State licensing systems vary substantially, but most have allowed quick and easy access to driving with full privileges at a young age, contributing to the crash problem. Formal driver education has not been an effective crash prevention measure. Following the introduction of graduated licensing in New Zealand, Australia, and Canada, this system has been considered in many states and has been implemented in some. Graduated systems phase in full privilege driving, requiring initial experience to be gained under conditions of lower risk. The author describes the first five multistage graduated systems enacted in the United States in 1996 and 1997. Factors that will influence the acceptability and effectiveness of these new licensing systems are discussed. Images p[452]-a p454-a p456-a p457-a p460-a PMID:10822470
NACA Study of Crash Fires with a Fairchild C-82 Packet
1950-06-21
Researchers at the National Advisory Committee for Aeronautics (NACA) Lewis Flight Propulsion Laboratory purposely crash a Fairchild C-82 Packet aircraft to study flame propagation. A rash of passenger aircraft crashes in 1946 and 1947 spurred a White House call for an investigatory board staffed by members of the Civil Aeronautics Board, military, and the NACA. The group addressed fire segregation, extinguishment, and prevention. The NACA established a Subcommittee on Aircraft Fire Prevention in February 1948 to coordinate its efforts. The Lewis team simulated situations in which an aircraft failed to become airborne during takeoff resulting in crashes into embankments and other objects. The Lewis researchers initially used surplus C-46 and C-82 military transport planes. In these situations, the aircraft generally suffered damage to its fuel system and other components, but was structurally survivable. The aircraft were mounted to a rail that ran down a 1700-foot long test runway. The aircraft was secured at the starting point with an anchor pier so it could get its engines up to takeoff speed before launching down the track. Barriers at the end of the runway were designed to simulate a variety of different types of crashes. Telemetry and high-speed cameras were crucial elements in these studies. The preliminary testing phase identified potential ignition sources and analyzed the spread of flammable materials.
Safety assessment tool for construction zone work phasing plans
DOT National Transportation Integrated Search
2016-05-01
The Highway Safety Manual (HSM) is the compilation of national safety research that provides quantitative methods for : analyzing highway safety. The HSM presents crash modification functions related to freeway work zone characteristics such as : wor...
Impact of non-freeway rumble strips phase 1.
DOT National Transportation Integrated Search
2012-06-26
In an effort to reduce lane-departure crashes, in 2008 the Michigan Department of Transportation (MDOT) began a : three-year statewide non-freeway rumble strip installation initiative. This initiative called for the installation of : milled centerlin...
Gopinath, Bamini; Jagnoor, Jagnoor; Elbers, Nieke; Cameron, Ian D
2017-02-01
Studies have shown that in people injured in a road traffic crash, persistent symptoms are common and can lead to significant ongoing personal impact. Hence, elucidating factors associated with the human costs are key to reducing the socio-economic burden of road traffic injuries. Therefore, in this study we aimed to track the experience and key outcomes of persons who had sustained mild/moderate injuries as they returned to health (and work, where relevant) following a road traffic crash. It is an inception study cohort of adults who had sustained mild to moderate injuries (that is, except serious injuries) in motor vehicle crashes in New South Wales, Australia, who were recruited and interviewed at baseline (within 3 months of the crash) and at 6, 12 and 24 months post-injury. We found that minor injuries had major impacts on pain ratings, physical and mental well-being, health-related quality of life and return to work and pre-injury participation during the 24 months post-injury phase. Further, for mild to moderately severe injuries, biopsychosocial factors appear to be prognostic indicators of recovery (not the location or type of injury). Examples of key biopsychosocial factors are: age; preinjury health; quality of life; reactions to injury (catastrophising, and pain); social support and the third party insurance compensation system. This study highlights the considerable impact of apparently "minor" road traffic crash injuries at a population level and suggests targeted approaches to the tertiary prevention of long-term morbidity and disability. Study findings have also reiterated the importance of looking beyond the injury to the 'whole person'.
CENTERLINE RUMBLE STRIPS SAFETY IMPACT EVALUATION—PHASE 2
DOT National Transportation Integrated Search
2018-02-02
Centerline rumble strips are used by various states as a low-cost countermeasure for mitigating cross-over crashes on two-way highways. This study performs a safety impact evaluation using an empirical Bayesian analysis. The researchers obtained a cr...
Determination of the maximum MGS mounting height : phase I crash testing.
DOT National Transportation Integrated Search
2012-03-09
Post-and-rail guardrail systems encounter environmental conditions, such as severe frost heave or erosion, which : may drastically affect the post embedment depth and rail mounting height. In addition, guardrail systems may be designed : to accommoda...
Fairchild C-82 Packet Destroyed in NACA Crash Fire Tests
1952-09-21
A Fairchild C-82 Packet is purposely destroyed by researchers at the National Advisory Committee for Aeronautics (NACA) Lewis Flight Propulsion Laboratory. In response to an escalating number of transport aircraft crashes in the mid-1940s, the NACA researchers undertook a decade-long investigation into a number of issues surrounding low-altitude aircraft crashes. The tests were conducted at the Ravenna Arsenal, approximately 60 miles south of the Lewis laboratory in Cleveland, Ohio. The aircraft were excess military transports from World War II. The aircraft was guided down the runway at speeds of 80 to 105 miles per hour. It came into contact with poles which tore open the 1500-gallon fuel tanks in the wings before reaching the barriers at the end of the runway. Fuel poured from the tanks and supply lines, resulting in the spread of both liquid fuel and a large cloud of spray. Solomon Weiss developed a method of dying the fuel red to improve its visibility during the crashes. This red fuel cloud trailed slightly behind the skidding aircraft, then rushed forward when the aircraft stopped. The nine-crash initial phase of testing used Lockheed C-56 Lodestar and C-82 transport aircraft to identify potential ignition sources and analyze the spread of flammable materials. The researchers were able to identify different classes of ignition sources, fuel disbursement patterns, the time when a particular ignition source might appear, rate of the fire spread, cabin survival times, and deceleration rates.
Assessment of roadway surface conditions using vehicle-intrinsic sensors, phase II.
DOT National Transportation Integrated Search
2016-06-28
Using onboard vehicle sensors to provide real-time identification of hazardous road surface conditions, such as the presence of ice, will allow drivers to receive warnings to proceed with caution on compromised road sections, thus reducing crash risk...
Determination of frontal offset test conditions based on crash data
DOT National Transportation Integrated Search
1998-01-01
This paper reports on the test procedure development : phase of the agencys Improved Frontal Protection : research program. It is anticipated that even after all cars : and light trucks have air bags for drivers and front seat : passengers there w...
Evaluation of a program to enhance young drivers' safety in Israel.
Toledo, Tomer; Lotan, Tsippy; Taubman-Ben-Ari, Orit; Grimberg, Einat
2012-03-01
Young drivers in Israel, as in other parts of the world, are involved in car crashes more than any other age group. The graduated driver licensing system in Israel requires that all new drivers be accompanied by an experienced driver whenever they drive for the first 3 months after obtaining a driving license. In an effort to make the accompanied driving phase more effective, a novel program which targets both young drivers and their parents was initiated in 2005. The program administers a personal meeting with the young driver and the accompanying parent scheduled for the beginning of the accompanied driving phase. In this meeting guidance is given regarding best practices for undertaking the accompanied driving, as well as tips for dealing with in-vehicle parent-teen dynamics. Through 2008, almost 130,000 families of young drivers have participated in the program. In order to evaluate the effectiveness of the program, injury crash records of the young drivers who participated in the program were compared with those of all other young drivers that were licensed at the same time period. The results obtained indicate statistically significant lower crash records for young drivers that participated in the program. Limitations of the evaluation related to self-selection biases are discussed, and practical implications are suggested. Copyright © 2011 Elsevier Ltd. All rights reserved.
Understanding the bursty electron cyclotron emission during a sawtooth crash in the HT-7 tokamak
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Erzhong, E-mail: rzhonglee@ipp.ac.cn; Hu, Liqun; Chen, Kaiyun
2014-01-15
Bursts in electron cyclotron emission (ECE) were observed during sawtooth crashes in HT-7 in discharges with ion cyclotron resonance heating injected near the q = 1 rational surface (q is the safety factor). The local ECE measurement indicated that the bursty radiation is only observed on channels near but a little away outward from the q = 1 magnetic surface. In conjunction with the soft x-ray tomography analysis, it was determined that, for the first time, only a compression process survives in the later stage of fast magnetic reconnection but before prompt heat transport. The compression enhanced the electron radiation temperature, the increased amplitudemore » of which agreed well with the estimation according to a kinetic compression theory model [R. J. Hastie and T. C. Hender, Nucl. Fusion 28, 585 (1988)]. This paper presents the experimental evidence that there indeed exists a transient compression phase which results in the bursty ECE radiation during a sawtooth crash.« less
DOT National Transportation Integrated Search
2006-08-01
Animal-vehicle collisions affect human safety, property and wildlife. The number of these types of collisions has increased : substantially over the last decades. This report describes the results of a project that explored the prospects for a relati...
DOT National Transportation Integrated Search
1988-08-01
This report details the results of an analysis performed to evaluate the : representativeness of the Crash Avoidance Research accident data base : (CARDfile). The accident records for 1983 and 1984 from six states (Indiana, : Maryland, Michigan, Penn...
DOT National Transportation Integrated Search
1985-12-01
This report details the results of an analysis performed to evaluate the representativeness of the Crash Avoidance Research accident data base (CARDfile). The accident records for 1983 and 1984 from six states (Indiana, Maryland, Michigan, Pennsylvan...
NASA Astrophysics Data System (ADS)
Voges-Schwieger, Kathrin; Hübner, Sven; Behrens, Bernd-Arno
2011-05-01
Metastable austenitic stainless steels change their lattice during forming operations by strain-induced alpha'-martensite formation. Temperatures below T = 20° C can accelerate the phase transformation while temperatures above T = 60° C may suppress the formation of martensite during the forming operation. In past investigations, the effect of high-strength martensitic regions in an austenitic ductile lattice was used in crash relevant parts for transportation vehicles. The local martensitic regions act as reinforcements leading to an increase in crash energy absorption. Moreover, they control the folding behavior as well as the force-distance-characteristic and increase the buckling resistance. This paper deals with a concerted thermomechanical drawing process to increase the local formation of alpha'-martensite caused by low temperatures.
Local evaluation report : state of Alabama (2001), automated crash notification system, UAB
DOT National Transportation Integrated Search
2005-01-01
This project is the pilot phase of a longer-term project to integrate ACN and AACN technology into a comprehensive trauma system. Such a system exists in Alabamas central Birmingham Regional EMS System (BREMSS). The project involves three tasks: t...
Impact of non-freeway rumble strips phase 1 : appendix I, driver behavior data for curve locations.
DOT National Transportation Integrated Search
2012-06-26
In an effort to reduce lane-departure crashes, in 2008 the Michigan Department of Transportation (MDOT) began a three-year statewide non-freeway rumble strip installation initiative. This initiative called for the installation of milled centerline ru...
Design Of An ITS-Level Advanced Traffic Management System, A Human Factors Perspective
DOT National Transportation Integrated Search
1999-09-01
The incidence of motorists violating the red phase of a traffic signal has been on the rise and is a contributing factor to intersection crashes. Technology has become available that automatically detects a motorist running the red light and records ...
Enhanced finite element analysis crash model of tractor-trailers (phase A)
DOT National Transportation Integrated Search
2008-10-28
On September 8, 1993, the Federal Highway Administration (FHWA) published a request for ITS FOTs. The concept for the SWIFT project was submitted in response to this request on January 6, 1994 by the SWIFT Project Team. The SWIFT Project Team propose...
DOT National Transportation Integrated Search
1999-06-01
The main purpose of Phase I of this project was to develop a methodology for predicting consequences of hazardous material (HM) crashes, such as injuries and property damage. An initial step in developing a risk assessment is to reliably estimate the...
Glider accidents: an analysis of 143 cases, 2001-2005.
van Doorn, Robert R A; de Voogt, Alexander J
2007-01-01
The majority of aviation crashes and casualties take place in general and sport aviation. Although gliding has gained popularity in recent decades, we could find no systematic analysis of glider accidents. This study determined factors associated with both non-fatal and fatal glider accidents to document their position within sport and general aviation accidents, and to suggest preventive measures and improvements. We performed a retrospective review of glider accidents for the period 2001-2005 in the database maintained by the U.S. National Transportation Safety Board (NTSB). A total of 117 non-fatal and 26 fatal glider accidents were reported for the 5-yr period. Adverse weather was the cause in 20% of all non-fatal accidents, 60% of which occurred in the cruise phase. Logistic regression revealed that fatal accidents were predicted by pilot error, flight phase, and home-built aircraft. Factors contributing to glider crashes are specific to this type of sport aviation. Owners of home-built gliders should pay particular attention to the aircraft's specifications and design limits.
Crash sequence based risk matrix for motorcycle crashes.
Wu, Kun-Feng; Sasidharan, Lekshmi; Thor, Craig P; Chen, Sheng-Yin
2018-04-05
Considerable research has been conducted related to motorcycle and other powered-two-wheeler (PTW) crashes; however, it always has been controversial among practitioners concerning with types of crashes should be first targeted and how to prioritize resources for the implementation of mitigating actions. Therefore, there is a need to identify types of motorcycle crashes that constitute the greatest safety risk to riders - most frequent and most severe crashes. This pilot study seeks exhibit the efficacy of a new approach for prioritizing PTW crash causation sequences as they relate to injury severity to better inform the application of mitigating countermeasures. To accomplish this, the present study constructed a crash sequence-based risk matrix to identify most frequent and most severe motorcycle crashes in an attempt to better connect causes and countermeasures of PTW crashes. Although the frequency of each crash sequence can be computed from crash data, a crash severity model is needed to compare the levels of crash severity among different crash sequences, while controlling for other factors that also have effects on crash severity such drivers' age, use of helmet, etc. The construction of risk matrix based on crash sequences involve two tasks: formulation of crash sequence and the estimation of a mixed-effects (ME) model to adjust the levels of severities for each crash sequence to account for other crash contributing factors that would have an effect on the maximum level of crash severity in a crash. Three data elements from the National Automotive Sampling System - General Estimating System (NASS-GES) data were utilized to form a crash sequence: critical event, crash types, and sequence of events. A mixed-effects model was constructed to model the severity levels for each crash sequence while accounting for the effects of those crash contributing factors on crash severity. A total of 8039 crashes involving 8208 motorcycles occurred during 2011 and 2013 were included in this study, weighted to represent 338,655 motorcyclists involved in traffic crashes in three years (2011-2013)(NHTSA, 2013). The top five most frequent and severe types of crash sequences were identified, accounting for 23 percent of all the motorcycle crashes included in the study, and they are (1) run-off-road crashes on the right, and hitting roadside objects, (2) cross-median crashes, and rollover, (3) left-turn oncoming crashes, and head-on, (4) crossing over (passing through) or turning into opposite direction at intersections, and (5) side-impacted. In addition to crash sequences, several other factors were also identified to have effects on crash severity: use of helmet, presence of horizontal curves, alcohol consumption, road surface condition, roadway functional class, and nighttime condition. Copyright © 2018 Elsevier Ltd. All rights reserved.
DOT National Transportation Integrated Search
2012-04-01
Louisianas crash rate is consistently among the highest in the nation, and it imposes signifi cant economic and social : costs on the state. Property damage, lost productivity, medical expenses, and infl ated motor vehicle insurance rates : impose...
DOT National Transportation Integrated Search
2016-05-01
The Highway Safety Manual (HSM) Part D provides a comprehensive list of the effects of safety treatments : (countermeasures). These effects are quantified by crash modification factors (CMF) which are based on compilation : from past studies of the e...
Brubacher, Jeffrey R.; Chan, Herbert; Erdelyi, Shannon; Schuurman, Nadine; Amram, Ofer
2016-01-01
Background British Columbia, Canada is a geographically large jurisdiction with varied environmental and socio-cultural contexts. This cross-sectional study examined variation in motor vehicle crash rates across 100 police patrols to investigate the association of crashes with key explanatory factors. Methods Eleven crash outcomes (total crashes, injury crashes, fatal crashes, speed related fatal crashes, total fatalities, single-vehicle night-time crashes, rear-end collisions, and collisions involving heavy vehicles, pedestrians, cyclists, or motorcyclists) were identified from police collision reports and insurance claims and mapped to police patrols. Six potential explanatory factors (intensity of traffic law enforcement, speed limits, climate, remoteness, socio-economic factors, and alcohol consumption) were also mapped to police patrols. We then studied the association between crashes and explanatory factors using negative binomial models with crash count per patrol as the response variable and explanatory factors as covariates. Results Between 2003 and 2012 there were 1,434,239 insurance claim collisions, 386,326 police reported crashes, and 3,404 fatal crashes. Across police patrols, there was marked variation in per capita crash rate and in potential explanatory factors. Several factors were associated with crash rates. Percent roads with speed limits ≤ 60 km/hr was positively associated with total crashes, injury crashes, rear end collisions, and collisions involving pedestrians, cyclists, and heavy vehicles; and negatively associated with single vehicle night-time crashes, fatal crashes, fatal speeding crashes, and total fatalities. Higher winter temperature was associated with lower rates of overall collisions, single vehicle night-time collisions, collisions involving heavy vehicles, and total fatalities. Lower socio-economic status was associated with higher rates of injury collisions, pedestrian collisions, fatal speeding collisions, and fatal collisions. Regions with dedicated traffic officers had fewer fatal crashes and fewer fatal speed related crashes but more rear end crashes and more crashes involving cyclists or pedestrians. The number of traffic citations per 1000 drivers was positively associated with total crashes, fatal crashes, total fatalities, fatal speeding crashes, injury crashes, single vehicle night-time crashes, and heavy vehicle crashes. Possible explanations for these associations are discussed. Conclusions There is wide variation in per capita rates of motor vehicle crashes across BC police patrols. Some variation is explained by factors such as climate, road type, remoteness, socioeconomic variables, and enforcement intensity. The ability of explanatory factors to predict crash rates would be improved if considered with local traffic volume by all travel modes. PMID:27099930
Physics of Financial Markets: Can we Understand the Unpredictable Phenomenon of Flash Crashes
NASA Astrophysics Data System (ADS)
Stanley, H. Eugene
2015-03-01
Dangerous vulnerability is hiding in complex systems. Indeed, disasters ranging from abrupt financial ``flash crashes'' and large-scale power outages to sudden death among the elderly dramatically exemplify this fact. While we can understand the cause of most events in complex systems, sudden unexpected ``black swans'' whether in economics or in the ``physicists world'' cry out for insight. To design more resilient systems we will describe recent results seeking understanding of these black swans. In many real-world phenomena, such as brain seizures in neuroscience or sudden market crashes in finance, after an inactive period of time a significant part of the damaged network is capable of spontaneously becoming active again. The process often occurs repeatedly. To model this marked network recovery, we examine the effect of local node recoveries and stochastic contiguous spreading, and find that they can lead to the spontaneous emergence of macroscopic ``phase-flipping'' phenomena. The fraction of active nodes switches back and forth between the two network collective modes characterized by high network activity and low network activity. Furthermore, the system exhibits a strong hysteresis behavior analogous to phase transitions near a critical point [A. Majdandzic, B. Podobnik, S. V. Buldyrev, D. Y. Kenett, S. Havlin, and H. E. Stanley, ``Spontaneous Recovery in Dynamic Networks,'' Nature Physics 10, 34 (2014)]. This work was carried out in collaboration with a number of colleagues, chief among whom are A. Majdanzic, B. Podobnik, S. V. Buldyrev, D. Y. Kenett, and S. Havlin.
Effect of electronic stability control on automobile crash risk.
Farmer, Charles
2004-12-01
Per vehicle crash involvement rates were compared for otherwise identical vehicle models with and without electronic stability control (ESC) systems. ESC was found to affect single-vehicle crashes to a greater extent than multiple-vehicle crashes, and crashes with fatal injuries to a greater extent than less severe crashes. Based on all police-reported crashes in 7 states over 2 years, ESC reduced single-vehicle crash involvement risk by approximately 41 percent (95 percent confidence limits 3348) and single-vehicle injury crash involvement risk by 41 percent (2752). This translates to an estimated 7 percent reduction in overall crash involvement risk (310) and a 9 percent reduction in overall injury crash involvement risk (314). Based on all fatal crashes in the United States over 3 years, ESC was found to have reduced single-vehicle fatal crash involvement risk by 56 percent (3968). This translates to an estimated 34 percent reduction in overall fatal crash involvement risk (2145).
Teoh, Eric R
2018-07-04
The objective of this study was to identify and quantify the motorcycle crash population that would be potential beneficiaries of 3 crash avoidance technologies recently available on passenger vehicles. Two-vehicle crashes between a motorcycle and a passenger vehicle that occurred in the United States during 2011-2015 were classified by type, with consideration of the functionality of 3 classes of passenger vehicle crash avoidance technologies: frontal crash prevention, lane maintenance, and blind spot detection. Results were expressed as the percentage of crashes potentially preventable by each type of technology, based on all known types of 2-vehicle crashes and based on all crashes involving motorcycles. Frontal crash prevention had the largest potential to prevent 2-vehicle motorcycle crashes with passenger vehicles. The 3 technologies in sum had the potential to prevent 10% of fatal 2-vehicle crashes and 23% of police-reported crashes. However, because 2-vehicle crashes with a passenger vehicle represent fewer than half of all motorcycle crashes, these technologies represent a potential to avoid 4% of all fatal motorcycle crashes and 10% of all police-reported motorcycle crashes. Refining the ability of passenger vehicle crash avoidance systems to detect motorcycles represents an opportunity to improve motorcycle safety. Expanding the capabilities of these technologies represents an even greater opportunity. However, even fully realizing these opportunities can affect only a minority of motorcycle crashes and does not change the need for other motorcycle safety countermeasures such as helmets, universal helmet laws, and antilock braking systems.
"Crashing the gates" - selection criteria for television news reporting of traffic crashes.
De Ceunynck, Tim; De Smedt, Julie; Daniels, Stijn; Wouters, Ruud; Baets, Michèle
2015-07-01
This study investigates which crash characteristics influence the probability that the crash is reported in the television news. To this purpose, all news items from the period 2006-2012 about traffic crashes from the prime time news of two Belgian television channels are linked to the official injury crash database. Logistic regression models are built for the database of all injury crashes and for the subset of fatal crashes to identify crash characteristics that correlate with a lower or higher probability of being reported in the news. A number of significant biases in terms of crash severity, time, place, types of involved road users and victims' personal characteristics are found in the media reporting of crashes. More severe crashes are reported in the media more easily than less severe crashes. Significant fluctuations in media reporting probability through time are found in terms of the year and month in which the crash took place. Crashes during week days are generally less reported in the news. The geographical area (province) in which the crash takes place also has a significant impact on the probability of being reported in the news. Crashes on motorways are significantly more represented in the news. Regarding the age of the involved victims, a clear trend of higher media reporting rates of crashes involving young victims or young fatalities is observed. Crashes involving female fatalities are also more frequently reported in the news. Furthermore, crashes involving a bus have a significantly higher probability of being reported in the news, while crashes involving a motorcycle have a significantly lower probability. Some models also indicate a lower reporting rate of crashes involving a moped, and a higher reporting rate of crashes involving heavy goods vehicles. These biases in media reporting can create skewed perceptions in the general public about the prevalence of traffic crashes and eventually may influence people's behaviour. Copyright © 2015 Elsevier Ltd. All rights reserved.
DOT National Transportation Integrated Search
2012-03-01
The purpose of this project was to identify the impacts of implementing speed limiters (SL) in commercial vehicle fleet operations. These impacts may be related to safety through a reduction in the number and/or severity of crashes, and/or address op...
DOT National Transportation Integrated Search
2001-04-28
An Institute of Transportation Engineers (ITE) test at 122 standard four-leg intersections in Long Island, NY, shows that retiming the length of the yellow/red phases of traffic signals can reduce serious and reportable accidents ($1,000-plus damage ...
Evaluation of fog predictions and detection, Phase 2 : draft final report.
DOT National Transportation Integrated Search
2016-09-01
On January 29, 2012 at about 4:00 am a thick fog and smoke caused a multiple car crash just south of Gainesville, Florida. 11 people were killed and 18 were hospitalized. Nationally there are about 38,000 fog related accidents which result in about 6...
DOT National Transportation Integrated Search
2008-02-01
The IVBSS program is a four-year, two-phase project to design and evaluate an integrated crash warning system for forward collision, lateral drift, lane-change merge, and curve speed warnings for both light vehicles and heavy trucks. This report, cov...
NASA Astrophysics Data System (ADS)
Henn, Philipp; Liewald, Mathias; Sindel, Manfred
2018-05-01
As lightweight design as well as crash performance are crucial to future car body design, exact material characterisation is important to use materials at their full potential and reach maximum efficiency. Within the scope of this paper, the potential of newly established bending-tension test procedure to characterise material crashworthiness is investigated. In this test setup for the determination of material failure, a buckling-bending test is coupled with a subsequent tensile test. If prior bending load is critical, tensile strength and elongation in the subsequent tensile test are dramatically reduced. The new test procedure therefore offers an applicable definition of failure as the incapacity of energy consumption in subsequent phases of the crash represents failure of a component. In addition to that, the correlation of loading condition with actual crash scenarios (buckling and free bending) is improved compared to three- point bending test. The potential of newly established bending-tension test procedure to characterise material crashworthiness is investigated in this experimental studys on two aluminium sheet alloys. Experimental results are validated with existing ductility characterisation from edge compression test.
Simulating the Response of a Composite Honeycomb Energy Absorber. Part 2; Full-Scale Impact Testing
NASA Technical Reports Server (NTRS)
Fasanella, Edwin L.; Annett, Martin S.; Jackson, Karen E.; Polanco, Michael A.
2012-01-01
NASA has sponsored research to evaluate an externally deployable composite honeycomb designed to attenuate loads in the event of a helicopter crash. The concept, designated the Deployable Energy Absorber (DEA), is an expandable Kevlar(Registered TradeMark) honeycomb. The DEA has a flexible hinge that allows the honeycomb to be stowed collapsed until needed during an emergency. Evaluation of the DEA began with material characterization of the Kevlar(Registered TradeMark)-129 fabric/epoxy, and ended with a full-scale crash test of a retrofitted MD-500 helicopter. During each evaluation phase, finite element models of the test articles were developed and simulations were performed using the dynamic finite element code, LS-DYNA(Registered TradeMark). The paper will focus on simulations of two full-scale impact tests involving the DEA, a mass-simulator and a full-scale crash of an instrumented MD-500 helicopter. Isotropic (MAT24) and composite (MAT58) material models, which were assigned to DEA shell elements, were compared. Based on simulations results, the MAT58 model showed better agreement with test.
Injury patterns and preventability in prehospital motor vehicle crash fatalities in Victoria.
Ryan, Matt; Stella, Julian; Chiu, Herman; Ragg, Michael
2004-08-01
To examine the pattern of anatomical injury in victims of motor vehicle crashes who die prior to reaching hospital. Cases were identified where death was an unexpected outcome. A retrospective review of autopsy case records including police reports, of all persons who died in motor vehicle crashes between 1 January 1998 and 31 December 1999 and underwent full autopsy at the Victorian Institute of Forensic Medicine (VIFM). Those cases where the victim died in the prehospital phase were examined. Abbreviate Injury Scores and Injury Severity Scores were calculated in each case. Bull's probit analysis was used to identify unexpected deaths. There were 352 motor road crash fatalities identified that underwent autopsy at the VIFM in the study period. Two hundred and six of these were prehospital deaths involving motor vehicles, which satisfied specified criteria. 82% (95% CI: 77.7-86.3%) of cases had Abbreviated Injury Scores of 5 (critical) or 6 (incompatible with life). 80.1% (95% CI: 75.7-84.5%) had an Injury Severity Score greater than 40. 36.9% (95% CI: 34.5-39.3%) of cases had the maximum Injury Severity score of 75. 88.8% (95% CI: 85-92.7%) of cases sustained a head injury and 83.9% (95% CI: 79.8-88.2%) a chest injury. Possibly preventable fatality was identified in 30 (14.6% 95% CI: 13.9-15.3%) cases. In motor vehicle crash fatalities, most victims who die before reaching hospital do so because of major injury, with the head and chest the commonest regions involved. A large proportion of these injuries could be considered unsurvivable regardless of treatment. Earlier intervention or retrieval of such patients is unlikely to influence outcome in the majority of cases.
Multivariate poisson lognormal modeling of crashes by type and severity on rural two lane highways.
Wang, Kai; Ivan, John N; Ravishanker, Nalini; Jackson, Eric
2017-02-01
In an effort to improve traffic safety, there has been considerable interest in estimating crash prediction models and identifying factors contributing to crashes. To account for crash frequency variations among crash types and severities, crash prediction models have been estimated by type and severity. The univariate crash count models have been used by researchers to estimate crashes by crash type or severity, in which the crash counts by type or severity are assumed to be independent of one another and modelled separately. When considering crash types and severities simultaneously, this may neglect the potential correlations between crash counts due to the presence of shared unobserved factors across crash types or severities for a specific roadway intersection or segment, and might lead to biased parameter estimation and reduce model accuracy. The focus on this study is to estimate crashes by both crash type and crash severity using the Integrated Nested Laplace Approximation (INLA) Multivariate Poisson Lognormal (MVPLN) model, and identify the different effects of contributing factors on different crash type and severity counts on rural two-lane highways. The INLA MVPLN model can simultaneously model crash counts by crash type and crash severity by accounting for the potential correlations among them and significantly decreases the computational time compared with a fully Bayesian fitting of the MVPLN model using Markov Chain Monte Carlo (MCMC) method. This paper describes estimation of MVPLN models for three-way stop controlled (3ST) intersections, four-way stop controlled (4ST) intersections, four-way signalized (4SG) intersections, and roadway segments on rural two-lane highways. Annual Average Daily traffic (AADT) and variables describing roadway conditions (including presence of lighting, presence of left-turn/right-turn lane, lane width and shoulder width) were used as predictors. A Univariate Poisson Lognormal (UPLN) was estimated by crash type and severity for each highway facility, and their prediction results are compared with the MVPLN model based on the Average Predicted Mean Absolute Error (APMAE) statistic. A UPLN model for total crashes was also estimated to compare the coefficients of contributing factors with the models that estimate crashes by crash type and severity. The model coefficient estimates show that the signs of coefficients for presence of left-turn lane, presence of right-turn lane, land width and speed limit are different across crash type or severity counts, which suggest that estimating crashes by crash type or severity might be more helpful in identifying crash contributing factors. The standard errors of covariates in the MVPLN model are slightly lower than the UPLN model when the covariates are statistically significant, and the crash counts by crash type and severity are significantly correlated. The model prediction comparisons illustrate that the MVPLN model outperforms the UPLN model in prediction accuracy. Therefore, when predicting crash counts by crash type and crash severity for rural two-lane highways, the MVPLN model should be considered to avoid estimation error and to account for the potential correlations among crash type counts and crash severity counts. Copyright © 2016 Elsevier Ltd. All rights reserved.
Night driving restrictions for youthful drivers: a literature review and commentary.
Williams, A F; Preusser, D F
1997-01-01
The research literature on night driving curfews is reviewed. Driving at night involves high risk, particularly for young beginners. Although only about 15 percent of the total miles of 16-17-year-old drivers occur between 9 p.m. and 6 a.m., about 40 percent of their fatal crashes take place during these hours. Curfews that limit recreational driving at night without an adult have been found to substantially reduce nighttime crashes. Parents of teenagers strongly endorse curfews and favor earlier starting times than prevail in most jurisdictions with curfews. A night driving curfew is an essential component of graduated licensing, a system that phases in young beginners to full-privilege licensure, limiting initial driving to lower-risk situations.
Doecke, Sam D; Kloeden, Craig N; Dutschke, Jeffrey K; Baldock, Matthew R J
2018-05-19
The objective of this article is to provide empirical evidence for safe speed limits that will meet the objectives of the Safe System by examining the relationship between speed limit and injury severity for different crash types, using police-reported crash data. Police-reported crashes from 2 Australian jurisdictions were used to calculate a fatal crash rate by speed limit and crash type. Example safe speed limits were defined using threshold risk levels. A positive exponential relationship between speed limit and fatality rate was found. For an example fatality rate threshold of 1 in 100 crashes it was found that safe speed limits are 40 km/h for pedestrian crashes; 50 km/h for head-on crashes; 60 km/h for hit fixed object crashes; 80 km/h for right angle, right turn, and left road/rollover crashes; and 110 km/h or more for rear-end crashes. The positive exponential relationship between speed limit and fatal crash rate is consistent with prior research into speed and crash risk. The results indicate that speed zones of 100 km/h or more only meet the objectives of the Safe System, with regard to fatal crashes, where all crash types except rear-end crashes are exceedingly rare, such as on a high standard restricted access highway with a safe roadside design.
Crash energy absorption of two-segment crash box with holes under frontal load
NASA Astrophysics Data System (ADS)
Choiron, Moch. Agus; Sudjito, Hidayati, Nafisah Arina
2016-03-01
Crash box is one of the passive safety components which designed as an impact energy absorber during collision. Crash box designs have been developed in order to obtain the optimum crashworthiness performance. Circular cross section was first investigated with one segment design, it rather influenced by its length which is being sensitive to the buckling occurrence. In this study, the two-segment crash box design with additional holes is investigated and deformation behavior and crash energy absorption are observed. The crash box modelling is performed by finite element analysis. The crash test components were impactor, crash box, and fixed rigid base. Impactor and the fixed base material are modelled as a rigid, and crash box material as bilinear isotropic hardening. Crash box length of 100 mm and frontal crash velocity of 16 km/jam are selected. Crash box material of Aluminum Alloy is used. Based on simulation results, it can be shown that holes configuration with 2 holes and ¾ length locations have the largest crash energy absorption. This condition associated with deformation pattern, this crash box model produces axisymmetric mode than other models.
Filtness, A J; Armstrong, K A; Watson, A; Smith, S S
2017-02-01
Sleep-related (SR) crashes are an endemic problem the world over. However, police officers report difficulties in identifying sleepiness as a crash contributing factor. One approach to improving the sensitivity of SR crash identification is by applying a proxy definition post hoc to crash reports. To identify the prominent characteristics of SR crashes and highlight the influence of proxy definitions, ten years of Queensland (Australia) police reports of crashes occurring in ≥100km/h speed zones were analysed. In Queensland, two approaches are routinely taken to identifying SR crashes. First, attending police officers identify crash causal factors; one possible option is 'fatigue/fell asleep'. Second, a proxy definition is applied to all crash reports. Those meeting the definition are considered SR and added to the police-reported SR crashes. Of the 65,204 vehicle operators involved in crashes 3449 were police-reported as SR. Analyses of these data found that male drivers aged 16-24 years within the first two years of unsupervised driving were most likely to have a SR crash. Collision with a stationary object was more likely in SR than in not-SR crashes. Using the proxy definition 9739 (14.9%) crashes were classified as SR. Using the proxy definition removes the findings that SR crashes are more likely to involve males and be of high severity. Additionally, proxy defined SR crashes are no less likely at intersections than not-SR crashes. When interpreting crash data it is important to understand the implications of SR identification because strategies aimed at reducing the road toll are informed by such data. Without the correct interpretation, funding could be misdirected. Improving sleepiness identification should be a priority in terms of both improvement to police and proxy reporting. Copyright © 2015 Elsevier Ltd. All rights reserved.
Seacrist, Thomas; Belwadi, Aditya; Prabahar, Abhiti; Chamberlain, Samuel; Megariotis, James; Loeb, Helen
2016-09-01
Motor vehicle crashes are the leading cause of death for teens. Previous teen and adult crash rates have been based upon fatal crashes, police-reported crashes, and estimated miles driven. Large-scale naturalistic driving studies offer the opportunity to compute crash rates using a reliable methodology to capture crashes and driving exposure. The Strategic Highway Research Program 2 (SHRP2) Naturalistic Driving Study contains extensive real-world data on teen and adult driving. This article presents findings on the crash rates of novice teen and experienced adult drivers in naturalistic crashes. A subset from the SHRP2 database consisting of 539 crash events for novice teens (16-19 years, n = 549) and experienced adults (35-54 years, n = 591) was used. Onboard instrumentation such as scene cameras, accelerometers, and Global Positioning System logged time series data at 10 Hz. Scene videos were reviewed for all events to identify rear-end striking crashes. Dynamic variables such as acceleration and velocity were analyzed for rear-end striking events. Number of crashes, crash rates, rear-end striking crash severity, and rear-end striking impact velocity were compared between novice teens and experienced adults. Video review of the SHRP2 crashes identified significantly more crashes (P < 0.01) and rear-end striking crashes (P < 0.01) among the teen group than among the adult group. This yielded crash rates of 30.0 crashes per million miles driven for novice teens compared to 5.3 crashes per million miles driven for experienced adults. The crash rate ratio for teens vs. adults was 5.7. The rear-end striking crash rate was 13.5 and 1.8 per million miles driven for novice teens and experienced adults, respectively. The rear-end striking crash rate ratio for teens vs. adults was 7.5. The rear-end striking crash severity measured by the accelerometers was greater (P < 0.05) for the teen group (1.8 ± 0.9 g; median = 1.6 g) than for the adult group (1.1 ± 0.4 g; median = 1.0 g), suggesting that teen crashes tend to be more serious than adult crashes. Increased rear-end striking impact velocity (P < 0.01) was also observed for novice teens (18.8 ± 13.2 mph; median = 18.9 mph) compared to experienced adults (3.3 ± 1.2 mph; median = 2.8 mph). To our knowledge, this is the first study to compare crash rates between teens and adults using a large-scale naturalistic driving database. Unlike previous crash rates, the reported rates reliably control for crash type and driving exposure. These results conform to previous findings that novice teens exhibit increased crash rates compared to experienced adults.
Sternlund, Simon
2017-05-29
Lane departure crashes account for a significant proportion of passenger car occupant fatalities and serious injuries. Utilizing real-world data involving fatal passenger car crashes in Sweden, the characteristics of lane departure crashes were identified and the safety potential of lane departure warning (LDW) systems was quantified. The material consisted of 104 in-depth studies of fatal passenger car crashes in 2010. The crashes were classified as single-vehicle (n = 48), head-on (n = 52), and overtaking (n = 4) crashes. These crash types were identified as crashes that could have potentially involved lane departure. A case-by-case analysis was carried out and lane departure crashes were identified and characterized using police reports and information collected by crash investigators at the Swedish Transport Administration; for example, inspections and photographs of the crash sites and of the involved vehicles. Lane departure crashes were separated from crashes where loss of control occurred pre-lane departure. Furthermore, loss of control post-lane departures were identified. When studying the pre-stage of lane departure without prior loss of control, crashes were categorized as unintentional drifting, intentional lane change, or evasive maneuver. Using previously published effectiveness information, the potential for LDW systems to prevent crashes was estimated. Of all crashes with passenger car occupant fatalities in Sweden in 2010, 46% (63/138) were found to relate to lane departure without prior loss of control. These crashes accounted for 61% (63/104) of all single-vehicle, head-on, and overtaking crashes. The remaining 41 crashes were due to loss of control pre-lane departure. Unintentional drifting accounted for 81% (51/63) of all lane departure crashes without prior loss of control, which corresponded to 37% (51/138) of all fatal passenger car occupant crashes. LDW systems were found to potentially prevent 33-38 of the 100 fatal head-on and single vehicle crashes. These crashes involved drifting and occurred on roads with visible lane markings, signed posted speed limits ≥70 km/h, and without rumble strips on the corresponding lane departure side. The range of potentially prevented crashes (33-38) is due to the inclusion or exclusion of crashes involving excessive speeding. In this study, approximately half (51/100) of all head-on and single-vehicle crashes were identified as being a consequence of drifting, where LDW systems had the potential to prevent the majority (33-38) of these crashes. The typical lane departure crash without prior loss of control occurred on undivided roads in rural areas with signed posted speed limits ≥70 km/h, where the center and side road markings were visible.
Crash energy absorption of two-segment crash box with holes under frontal load
DOE Office of Scientific and Technical Information (OSTI.GOV)
Choiron, Moch Agus, E-mail: agus-choiron@ub.ac.id; Sudjito,; Hidayati, Nafisah Arina
Crash box is one of the passive safety components which designed as an impact energy absorber during collision. Crash box designs have been developed in order to obtain the optimum crashworthiness performance. Circular cross section was first investigated with one segment design, it rather influenced by its length which is being sensitive to the buckling occurrence. In this study, the two-segment crash box design with additional holes is investigated and deformation behavior and crash energy absorption are observed. The crash box modelling is performed by finite element analysis. The crash test components were impactor, crash box, and fixed rigid base.more » Impactor and the fixed base material are modelled as a rigid, and crash box material as bilinear isotropic hardening. Crash box length of 100 mm and frontal crash velocity of 16 km/jam are selected. Crash box material of Aluminum Alloy is used. Based on simulation results, it can be shown that holes configuration with 2 holes and ¾ length locations have the largest crash energy absorption. This condition associated with deformation pattern, this crash box model produces axisymmetric mode than other models.« less
Gasoline prices and their relationship to drunk-driving crashes.
Chi, Guangqing; Zhou, Xuan; McClure, Timothy E; Gilbert, Paul A; Cosby, Arthur G; Zhang, Li; Robertson, Angela A; Levinson, David
2011-01-01
This study investigates the relationship between changing gasoline prices and drunk-driving crashes. Specifically, we examine the effects of gasoline prices on drunk-driving crashes in Mississippi by several crash types and demographic groups at the monthly level from 2004 to 2008, a period experiencing great fluctuation in gasoline prices. An exploratory visualization by graphs shows that higher gasoline prices are generally associated with fewer drunk-driving crashes. Higher gasoline prices depress drunk-driving crashes among young and adult drivers, among male and female drivers, and among white and black drivers. Results from negative binomial regression models show that when gas prices are higher, there are fewer drunk-driving crashes, particularly among property-damage-only crashes. When alcohol consumption levels are higher, there are more drunk-driving crashes, particularly fatal and injury crashes. The effects of gasoline prices and alcohol consumption are stronger on drunk-driving crashes than on all crashes. The findings do not vary much across different demographic groups. Overall, gasoline prices have greater effects on less severe crashes and alcohol consumption has greater effects on more severe crashes. Copyright © 2010 Elsevier Ltd. All rights reserved.
Crash avoidance potential of four large truck technologies.
Jermakian, Jessica S
2012-11-01
The objective of this paper was to estimate the maximum potential large truck crash reductions in the United States associated with each of four crash avoidance technologies: side view assist, forward collision warning/mitigation, lane departure warning/prevention, and vehicle stability control. Estimates accounted for limitations of current systems. Crash records were extracted from the 2004-08 files of the National Automotive Sampling System General Estimates System (NASS GES) and the Fatality Analysis Reporting System (FARS). Crash descriptors such as location of damage on the vehicle, road characteristics, time of day, and precrash maneuvers were reviewed to determine whether the information or action provided by each technology potentially could have prevented the crash. Of the four technologies, side view assist had the greatest potential for preventing large truck crashes of any severity; the technology is potentially applicable to 39,000 crashes in the United States each year, including 2000 serious and moderate injury crashes and 79 fatal crashes. Vehicle stability control is another promising technology, with the potential to prevent or mitigate up to 31,000 crashes per year including more serious crashes--up to 7000 moderate-to-serious injury crashes and 439 fatal crashes per year. Vehicle stability control could prevent or mitigate up to 20 and 11 percent of moderate-to-serious injury and fatal large truck crashes, respectively. Forward collision warning has the potential to prevent as many as 31,000 crashes per year, including 3000 serious and moderate injury crashes and 115 fatal crashes. Finally, 10,000 large truck crashes annually were relevant to lane departure warning/prevention systems. Of these, 1000 involved serious and moderate injuries and 247 involved fatal injuries. There is great potential effectiveness for truck-based crash avoidance systems. However, it is yet to be determined how drivers will interact with the systems. Actual effectiveness of crash avoidance systems will not be known until sufficient real-world experience has been gained. Copyright © 2012 Elsevier Ltd. All rights reserved.
A classification tree based modeling approach for segment related crashes on multilane highways.
Pande, Anurag; Abdel-Aty, Mohamed; Das, Abhishek
2010-10-01
This study presents a classification tree based alternative to crash frequency analysis for analyzing crashes on mid-block segments of multilane arterials. The traditional approach of modeling counts of crashes that occur over a period of time works well for intersection crashes where each intersection itself provides a well-defined unit over which to aggregate the crash data. However, in the case of mid-block segments the crash frequency based approach requires segmentation of the arterial corridor into segments of arbitrary lengths. In this study we have used random samples of time, day of week, and location (i.e., milepost) combinations and compared them with the sample of crashes from the same arterial corridor. For crash and non-crash cases, geometric design/roadside and traffic characteristics were derived based on their milepost locations. The variables used in the analysis are non-event specific and therefore more relevant for roadway safety feature improvement programs. First classification tree model is a model comparing all crashes with the non-crash data and then four groups of crashes (rear-end, lane-change related, pedestrian, and single-vehicle/off-road crashes) are separately compared to the non-crash cases. The classification tree models provide a list of significant variables as well as a measure to classify crash from non-crash cases. ADT along with time of day/day of week are significantly related to all crash types with different groups of crashes being more likely to occur at different times. From the classification performance of different models it was apparent that using non-event specific information may not be suitable for single vehicle/off-road crashes. The study provides the safety analysis community an additional tool to assess safety without having to aggregate the corridor crash data over arbitrary segment lengths. Copyright © 2010. Published by Elsevier Ltd.
A novel approach for analyzing severe crash patterns on multilane highways.
Pande, Anurag; Abdel-Aty, Mohamed
2009-09-01
This study presents a novel approach for analysis of patterns in severe crashes that occur on mid-block segments of multilane highways with partially limited access. A within stratum matched crash vs. non-crash classification approach is adopted towards that end. Under this approach crashes serve as units of analysis and it does not require aggregation of crash data over arterial segments of arbitrary lengths. Also, the proposed approach does not use information on non-severe crashes and hence is not affected by under-reporting of the minor crashes. Random samples of time, day of week, and location (i.e., milepost) combinations were collected for multilane arterials in the state of Florida and matched with severe crashes from the corresponding corridor to form matched strata consisting of severe crash and non-crash cases. For these cases, geometric design/roadside and traffic characteristics were derived based on the corresponding milepost locations. Four groups of crashes, severe rear-end, lane-change related, pedestrian, and single-vehicle/off-road crashes, on multilane arterials segments were compared separately to the non-crash cases. Severe lane-change related crashes may primarily be attributed to exposure while single-vehicle crashes and pedestrian crashes have no significant relationship with the ADT (Average Daily Traffic). For severe rear-end crashes speed limit, ADT, K-factor, time of day/day of week, median type, pavement condition, and presence of horizontal curvature were significant factors. The proposed approach uses general roadway characteristics as independent variables rather than event-specific information (i.e., crash characteristics such as driver/vehicle details); it has the potential to fit within a safety evaluation framework for arterial segments.
Pre-crash scenario typology for crash avoidance research
DOT National Transportation Integrated Search
2007-04-01
This report defines a new pre-crash scenario typology for crash avoidance research based on the 2004 General Estimates System (GES) crash database, which consists of pre-crash scenarios depicting vehicle movements and dynamics as well as the critical...
Safety analytics for integrating crash frequency and real-time risk modeling for expressways.
Wang, Ling; Abdel-Aty, Mohamed; Lee, Jaeyoung
2017-07-01
To find crash contributing factors, there have been numerous crash frequency and real-time safety studies, but such studies have been conducted independently. Until this point, no researcher has simultaneously analyzed crash frequency and real-time crash risk to test whether integrating them could better explain crash occurrence. Therefore, this study aims at integrating crash frequency and real-time safety analyses using expressway data. A Bayesian integrated model and a non-integrated model were built: the integrated model linked the crash frequency and the real-time models by adding the logarithm of the estimated expected crash frequency in the real-time model; the non-integrated model independently estimated the crash frequency and the real-time crash risk. The results showed that the integrated model outperformed the non-integrated model, as it provided much better model results for both the crash frequency and the real-time models. This result indicated that the added component, the logarithm of the expected crash frequency, successfully linked and provided useful information to the two models. This study uncovered few variables that are not typically included in the crash frequency analysis. For example, the average daily standard deviation of speed, which was aggregated based on speed at 1-min intervals, had a positive effect on crash frequency. In conclusion, this study suggested a methodology to improve the crash frequency and real-time models by integrating them, and it might inspire future researchers to understand crash mechanisms better. Copyright © 2017 Elsevier Ltd. All rights reserved.
Intelligent geocoding system to locate traffic crashes.
Qin, Xiao; Parker, Steven; Liu, Yi; Graettinger, Andrew J; Forde, Susie
2013-01-01
State agencies continue to face many challenges associated with new federal crash safety and highway performance monitoring requirements that use data from multiple and disparate systems across different platforms and locations. On a national level, the federal government has a long-term vision for State Departments of Transportation (DOTs) to report state route and off-state route crash data in a single network. In general, crashes occurring on state-owned or state maintained highways are a priority at the Federal and State level; therefore, state-route crashes are being geocoded by state DOTs. On the other hand, crashes occurring on off-state highway system do not always get geocoded due to limited resources and techniques. Creating and maintaining a statewide crash geographic information systems (GIS) map with state route and non-state route crashes is a complicated and expensive task. This study introduces an automatic crash mapping process, Crash-Mapping Automation Tool (C-MAT), where an algorithm translates location information from a police report crash record to a geospatial map and creates a pinpoint map for all crashes. The algorithm has approximate 83 percent mapping rate. An important application of this work is the ability to associate the mapped crash records to underlying business data, such as roadway inventory and traffic volumes. The integrated crash map is the foundation for effective and efficient crash analyzes to prevent highway crashes. Published by Elsevier Ltd.
Ims, Rolf A.; Henden, John-André; Thingnes, Anders V.; Killengreen, Siw T.
2013-01-01
Production cycles in birds are proposed as prime cases of indirect interactions in food webs. They are thought to be driven by predators switching from rodents to bird nests in the crash phase of rodent population cycles. Although rodent cycles are geographically widespread and found in different rodent taxa, bird production cycles appear to be most profound in the high Arctic where lemmings dominate. We hypothesized that this may be due to arctic lemmings inducing stronger predator responses than boreal voles. We tested this hypothesis by estimating predation rates in dummy bird nests during a rodent cycle in low-Arctic tundra. Here, the rodent community consists of a spatially variable mix of one lemming (Lemmus lemmus) and two vole species (Myodes rufocanus and Microtus oeconomus) with similar abundances. In consistence with our hypothesis, lemming peak abundances predicted well crash-phase nest predation rates, whereas the vole abundances had no predictive ability. Corvids were found to be the most important nest predators. Lemmings appear to be accessible to the whole predator community which makes them particularly powerful drivers of food web dynamics. PMID:24173526
Development of 780MPa grade gal annealed dual phase steel sheets for automobile
NASA Astrophysics Data System (ADS)
Jiang, Yinghua; Xie, Chunqian; Kuang, Shuang
2018-01-01
As the weight reduction of automotive body and crash safety become much more important factors, in an effort to satisfy these requirements, Shougang has developed 780MPa grade galvannealed dual phase steel sheet. Steel chemistry with low C and low Si was designed for good zinc wettability and spot weldability. And some of elements were added to improve the hole expansibility and work hardening capacity of steel as these effectively refine the microstructure and introduce retained austenite. Newly developed 780MPa grade galvannealed dual phase steels have a high yield strength and a good hole expansibility.
DOE Office of Scientific and Technical Information (OSTI.GOV)
DiNapoli, N.; Fitzpatrick, M.; Strother, C.
1977-11-01
Phase I identified trends leading to the desired national social goals of the mid-1980's in vehicle crashworthiness, crash avoidance, damageability, pedestrian safety, fuel economy, emissions and cost, and characterized an RSV to satisfy them. In Phase II an RSV prototype was designed, developed and tested to demonstrate the feasibility of meeting these goals simultaneously. Although further refinement is necessary to assure operational validity, in all categories the results meet or exceed the most advanced performance specified by The Presidential Task Force on Motor Vehicle Goals beyond 1980.
The frequency--severity indeterminacy.
Hauer, Ezra
2006-01-01
Nothing is known about unreported crashes; the information we have is of reported crashes only. Whether a crash gets reported depends on its severity. It follows by logic that, using only data about reported crashes, it is impossible to say whether a change or difference in crash counts reflects a change or difference in crash frequency or in crash severity. This indeterminacy has practical implications. Examples discussed are of the misattribution of over-representation in reported crashes of older drivers and of trucks to causal factors related to the frequency of crash involvement, and of misinterpretation by researchers of findings about the rollover propensity of SUVs.
Harland, Karisa K; Greenan, Mitchell; Ramirez, Marizen
2014-09-01
Although approximately one-third of agricultural equipment-related crashes occur near town, these crashes are thought to be a rural problem. This analysis examines differences between agricultural equipment-related crashes by their urban-rural distribution and distance from a town. Agricultural equipment crashes were collected from nine Midwest Departments of Transportation (2005-2008). Crash zip code was assigned as urban or rural (large, small and isolated) using Rural-Urban Commuting Areas. Crash proximity to a town was estimated with ArcGIS. Multivariable logistic regression was used to estimate the odds of crashing in an urban versus rural zip codes and across rural gradients. ANOVA analysis estimated mean distance (miles) from a crash site to a town. Over four years, 4444 crashes involved agricultural equipment. About 30% of crashes occurred in urban zip codes. Urban crashes were more likely to be non-collisions (aOR=1.69[1.24-2.30]), involve ≥2 vehicles (2 vehicles: aOR=1.58[1.14-2.20], 3+ vehicles: aOR=1.68[0.98-2.88]), occur in a town (aOR=2.06[1.73-2.45]) and within one mile of a town (aOR=1.65[1.40-1.95]) than rural crashes. The proportion of crashes within a town differed significantly across rural gradients (P<0.0001). Small rural crashes, compared to isolated rural crashes, were 1.98 (95%CI[1.28-3.06]) times more likely to be non-collisions. The distance from the crash to town differed significantly by the urban-rural distribution (P<0.0001). Crashes with agricultural equipment are unexpectedly common in urban areas and near towns and cities. Education among all roadway users, increased visibility of agricultural equipment and the development of complete rural roads are needed to increase road safety and prevent agricultural equipment-related crashes. Copyright © 2014 Elsevier Ltd. All rights reserved.
Crash avoidance potential of four passenger vehicle technologies.
Jermakian, Jessica S
2011-05-01
The objective was to update estimates of maximum potential crash reductions in the United States associated with each of four crash avoidance technologies: side view assist, forward collision warning/mitigation, lane departure warning/prevention, and adaptive headlights. Compared with previous estimates (Farmer, 2008), estimates in this study attempted to account for known limitations of current systems. Crash records were extracted from the 2004-08 files of the National Automotive Sampling System General Estimates System (NASS GES) and the Fatality Analysis Reporting System (FARS). Crash descriptors such as vehicle damage location, road characteristics, time of day, and precrash maneuvers were reviewed to determine whether the information or action provided by each technology potentially could have prevented or mitigated the crash. Of the four crash avoidance technologies, forward collision warning/mitigation had the greatest potential for preventing crashes of any severity; the technology is potentially applicable to 1.2 million crashes in the United States each year, including 66,000 serious and moderate injury crashes and 879 fatal crashes. Lane departure warning/prevention systems appeared relevant to 179,000 crashes per year. Side view assist and adaptive headlights could prevent 395,000 and 142,000 crashes per year, respectively. Lane departure warning/prevention was relevant to the most fatal crashes, up to 7500 fatal crashes per year. A combination of all four current technologies potentially could prevent or mitigate (without double counting) up to 1,866,000 crashes each year, including 149,000 serious and moderate injury crashes and 10,238 fatal crashes. If forward collision warning were extended to detect objects, pedestrians, and bicyclists, it would be relevant to an additional 3868 unique fatal crashes. There is great potential effectiveness for vehicle-based crash avoidance systems. However, it is yet to be determined how drivers will interact with the systems. The actual effectiveness of these systems will not be known until sufficient real-world experience has been gained. Copyright © 2010 Elsevier Ltd. All rights reserved.
Stigson, H
2009-06-01
The objective in this study, using data from crashed cars fitted with on-board crash pulse recorders, was to present differences in average crash severity, distribution of crash severity, and injury outcomes, based on an independent safety rating of roads, also taking road type and speed limit into consideration. Furthermore, the objective was to evaluate differences in injury risk, based on the distribution of crash severity. The investigation included both frontal two-vehicle crashes and single-vehicle crashes with known injury outcome. In total, 209 real-world crashes involving cars fitted with crash pulse recorders were included. For all crashes, average mean acceleration and change of velocity of the vehicle acceleration pulse were measured and calculated. All crash spots were classified according to an independent road safety rating program (European Road Assessment Programme Road Protection Score), where the safety quality of roads is rated in relation to posted speed limits. The crash severity and injury outcome in crashes that occurred on roads with good safety ratings were compared with crashes on roads with poor safety ratings. The data were also divided into subcategories according to posted speed limit and road type, to evaluate whether there was a difference in crash severity and injury outcome within the categories. In total, crash severity was statistically significantly lower in crashes occurring on roads with good safety ratings than in crashes occurring on roads with poor safety ratings. It was found that crash severity and injury risk were lower on roads with good safety ratings with a speed limit of above 90 km/h compared with roads with poor safety ratings, irrespective of speed limit. On the other hand, crash severity was higher on roads with good safety ratings with speed limit of 70 km/h than on roads with poor safety ratings with the same speed limit. Though it was found that a higher speed limit resulted in higher crash severity on roads with poor safety ratings, the opposite was found on roads with good safety ratings. The main reason for this was that lanes for traffic traveling in opposite directions were more often separated at higher speeds on roads with good safety ratings. On divided roads with good safety ratings, there were no crashes resulting in crash severity above the level corresponding to a 10 percent risk of sustaining serious or fatal injury. This indicates that one of the most important safety measures is divided roads.
Characteristics of Single Vehicle Crashes with a Teen Driver in South Carolina, 2005-2008.
Shults, Ruth A; Bergen, Gwen; Smith, Tracy J; Cook, Larry; Kindelberger, John; West, Bethany
2017-09-22
Teens' crash risk is highest in the first years of independent driving. Circumstances surrounding fatal crashes have been widely documented, but less is known about factors related to nonfatal teen driver crashes. This study describes single vehicle nonfatal crashes involving the youngest teen drivers (15-17 years), compares these crashes to single vehicle nonfatal crashes among adult drivers (35-44 years) and examines factors related to nonfatal injury producing crashes for teen drivers. Police crash data linked to hospital inpatient and emergency department data for 2005-2008 from the South Carolina Crash Outcomes Data Evaluation System (CODES) were analyzed. Nonfatal, single vehicle crashes involving passenger vehicles occurring on public roadways for teen (15-17 years) drivers were compared with those for adult (35-44 years) drivers on temporal patterns and crash risk factors per licensed driver and per vehicle miles traveled. Vehicle miles traveled by age group was estimated using data from the 2009 National Household Travel Survey. Multivariable log-linear regression analysis was conducted for teen driver crashes to determine which characteristics were related to crashes resulting in a minor/moderate injury or serious injury to at least one vehicle occupant. Compared with adult drivers, teen drivers in South Carolina had 2.5 times the single vehicle nonfatal crash rate per licensed driver and 11 times the rate per vehicle mile traveled. Teen drivers were nearly twice as likely to be speeding at the time of the crash compared with adult drivers. Teen driver crashes per licensed driver were highest during the afternoon hours of 3:00-5:59 pm and crashes per mile driven were highest during the nighttime hours of 9:00-11:59 pm. In 66% of the teen driver crashes, the driver was the only occupant. Crashes were twice as likely to result in serious injury when teen passengers were present than when the teen driver was alone. When teen drivers crashed while transporting teen passengers, the passengers were >5 times more likely to all be restrained if the teen driver was restrained. Crashes in which the teen driver was unrestrained were 80% more likely to result in minor/moderate injury and 6 times more likely to result in serious injury compared with crashes in which the teen driver was restrained. Despite the reductions in teen driver crashes associated with Graduated Driver Licensing (GDL), South Carolina's teen driver crash rates remain substantially higher than those for adult drivers. Established risk factors for fatal teen driver crashes, including restraint nonuse, transporting teen passengers, and speeding also increase the risk of nonfatal injury in single vehicle crashes. As South Carolina examines strategies to further reduce teen driver crashes and associated injuries, the state could consider updating its GDL passenger restriction to either none or one passenger <21years and dropping the passenger restriction exemption for trips to and from school. Surveillance systems such as CODES that link crash data with health outcome data provide needed information to more fully understand the circumstances and consequences of teen driver nonfatal crashes and evaluate the effectiveness of strategies to improve teen driver safety. Published by Elsevier Ltd.
Factors influencing pre-hospital care time intervals in Iran: a qualitative study.
Khorasani-Zavareh, Davoud; Mohammadi, Reza; Bohm, Katarina
2018-06-23
Pre-hospital time management provides better access to victims of road traffic crashes (RTCs) and can help minimize preventable deaths, injuries and disabilities. While most studies have been focused on measuring various time intervals in the pre-hospital phase, to our best knowledge there is no study exploring the barriers and facilitators that affects these various intervals qualitatively. The present study aimed to explore factors affecting various time intervals relating to road traffic incidents in the pre-hospital phase and provides suggestions for improvements in Iran. The study was conducted during 2013-2014 at both the national and local level in Iran. Overall, 18 face-to-face interviews with emergency medical services (EMS) personnel were used for data collection. Qualitative content analysis was employed to analyze the data. The most important barriers in relation to pre-hospital intervals were related to the manner of cooperation by members of the public with the EMS and their involvement at the crash scene, as well as to pre-hospital system factors, including the number and location of EMS facilities, type and number of ambulances and manpower. These factors usually affect how rapidly the EMS can arrive at the scene of the crash and how quickly victims can be transferred to hospital. These two categories have six main themes: notification interval; activation interval; response interval; on-scene interval; transport interval; and delivery interval. Despite more focus on physical resources, cooperation from members of the public needs to be taken in account in order to achieve better pre-hospital management of the various intervals, possibly through the use of public education campaigns.
Crash and risky driving involvement among novice adolescent drivers and their parents.
Simons-Morton, Bruce G; Ouimet, Marie Claude; Zhang, Zhiwei; Klauer, Sheila E; Lee, Suzanne E; Wang, Jing; Albert, Paul S; Dingus, Thomas A
2011-12-01
We compared rates of risky driving among novice adolescent and adult drivers over the first 18 months of adolescents' licensure. Data-recording systems installed in participants' vehicles provided information on driving performance of 42 newly licensed adolescent drivers and their parents. We analyzed crashes and near crashes and elevated g-force event rates by Poisson regression with random effects. During the study period, adolescents were involved in 279 crashes or near crashes (1 involving injury); parents had 34 such accidents. The incidence rate ratio (IRR) comparing adolescent and parent crash and near-crash rates was 3.91. Among adolescent drivers, elevated rates of g-force events correlated with crashes and near crashes (r = 0.60; P < .001). The IRR comparing incident rates of risky driving among adolescents and parents was 5.08. Adolescents' rates of crashes and near crashes declined with time (with a significant uptick in the last quarter), but elevated g-force event rates did not decline. Elevated g-force events among adolescents may have contributed to crash and near-crash rates that remained much higher than adult levels after 18 months of driving.
Casualty Crash Types for which Teens are at Excess Risk
Bingham, C. R.; Shope, J. T.
2007-01-01
This study identified casualty crash types for which teen drivers experience excess risk relative to adults. Michigan State Police crash records were used to examine casualty crashes in two statewide populations of drivers who experienced at least one crash from 1989–1996 (pre-graduated driver licensing in Michigan): teens (ages 16–19) and adults (ages 45–65). Rates and rate ratios (RR) based on crash occurrence per 100,000 person miles driven (PMD) compared teens and adults from the two statewide populations. Excess risk was defined as a RR for a specific type of crash that was significantly greater than the RR for all crashes combined. The RRs for all crashes combined for teenage males was 2.41 and 1.75 for teenage females. RRs for teenage males ranged from a low of 2.16 for casualty crashes attributed to alcohol to 8.98 for casualty road departure crashes at night. Among teenage females, RRs ranged from 2.06 for casualty crashes on the weekend to 7.86 for casualty crashes at night with passengers. Casualty crash rates for teenage males ranged from 0.21 per 100,000 PMD for rollover crashes to 1.95 per 100,000 PMD for crashes with passengers. Among teen females, casualty crash rates ranged from 0.21 per 100,000 PMD for drink/driving with passengers to 3.31 per 100,000 PMD for crashes with passengers. Implications for graduated driver licensing, teen driver supervision, and policy are discussed. This study was funded by the National Institute on Alcohol Abuse and Alcoholism and the Centers for Disease Control and Prevention’s National Center for Injury Prevention and Control. PMID:18184510
Crashes of sightseeing helicopter tours in Hawaii.
Haaland, Wren L; Shanahan, Dennis F; Baker, Susan P
2009-07-01
Crashes of sightseeing helicopter flights in Hawaii and the resulting tourist deaths prompted the FAA to issue regulations in 1994 specific to air tours in Hawaii. Research was undertaken to examine the effect of the 1994 Rule and to describe the circumstances of such crashes. From National Transportation Safety Board data, 59 crashes of helicopter air tour flights in Hawaii during 1981-2008 were identified; crash investigation reports were read and coded. Crashes in 1995-2008 were compared with those in 1981-1994. The 1994 Rule was followed by a 47% decrease in the crash rate, from 3.4 to 1.8/100,000 flight hours. The number of crashes into the ocean decreased from eight before the Rule to one afterwards. VFR-IMC crashes increased from 5 to 32% of crashes. There were 46 tourists and 9 pilots who died in 16 fatal crashes. Aircraft malfunctions, primarily due to poor maintenance, precipitated 34 (58%) of the crashes and persisted throughout the 28-yr period. Pilot errors were apparent in 23 crashes (39%). Flight from visual to instrument conditions occurred in two cases before the Rule and seven cases after. Terrain unsuitable for landing was cited in 37 crashes (63%). Decreases occurred in the overall number and rate of crashes and in ocean crash landings. The increase in VFR-IMC crashes may be related to the requirement that tour helicopters fly at least 1500 ft. above terrain. Attention is still needed to maintenance, pilot training, and restricting flights to operating areas and conditions that enable safe emergency landings.
Fatal light aircraft accidents in Ontario: a five year study.
Shkrum, M J; Hurlbut, D J; Young, J G
1996-03-01
Fatal civil aviation crashes in Ontario from 1985 to 1989 were studied. Data regarding accident circumstances, injury patterns and medical factors (disease, alcohol/drugs) which could have contributed to accident causation was obtained from a review of the files of the Chief Coroner for Ontario in Toronto and the aviation occurrence reports of the Transportation Safety Board of Canada. Forty-seven crashes involving mainly general aviation type aircraft but also 2 gyroplanes, 2 ultralights and a glider were reviewed. About half occurred during the cruise phase of the flight. Seventy (40 pilots; 30 passengers) of the 98 occupants died. The bodies of 68 victims were recovered; 63 were dead at the scene and 5 survived up to ten hours after impact. Multiple trauma killed about half of all the victims (n = 34); 29% (n = 20) drowned; 16% (n = 11) and 3% (n = 2) died of head/neck injuries and coronary disease respectively. Neck trauma was observed mostly in pilots and was the most frequent major blunt trauma injury in drowning victims. Passengers sustained relatively more craniofacial fractures and abdominal/retroperitoneal trauma. Pilot error was the most frequent cause of crashes (55%; 26/47 impacts) followed by mechanical failure (15%; 7/47) and adverse weather/environmental conditions (11%; 5/47). Coronary artery disease incapacitated two pilots (4% of crashes) and ethanol intoxication was implicated in two other accidents. Other drugs did not appear to be a definite factor in accident causation.
Sleep-related vehicle crashes on low speed roads.
Filtness, A J; Armstrong, K A; Watson, A; Smith, S S
2017-02-01
Very little is known about the characteristics of sleep related (SR) crashes occurring on low speed roads compared with current understanding of the role of sleep in crashes occurring on high speed roads e.g. motorways. To address this gap, analyses were undertaken to identify the differences and similarities between (1) SR crashes occurring on roads with low (≤60km/h) and high (≥100km/h) speed limits, and (2) SR crashes and not-SR crashes occurring on roads with low speed limits. Police reports of all crashes occurring on low and high speed roads over a ten year period between 2000 and 2009 were examined for Queensland, Australia. Attending police officers identified all crash attributes, including 'fatigue/fell asleep', which indicates that the police believe the crash to have a causal factor relating to falling asleep, sleepiness due to sleep loss, time of day, or fatigue. Driver or rider involvement in crashes was classified as SR or not-SR. All crash-associated variables were compared using Chi-square tests (Cramer's V=effect size). A series of logistic regression was performed, with driver and crash characteristics as predictors of crash category. A conservative alpha level of 0.001 determined statistical significance. There were 440,855 drivers or riders involved in a crash during this time; 6923 (1.6%) were attributed as SR. SR crashes on low speed roads have similar characteristics to those on high speed roads with young (16-24y) males consistently over represented. SR crashes on low speed roads are noticeably different to not-SR crashes in the same speed zone in that male and young novice drivers are over represented and outcomes are more severe. Of all the SR crashes identified, 41% occurred on low speed roads. SR crashes are not confined to high speed roads. Low speed SR crashes warrant specific investigation because they occur in densely populated areas, exposing a greater number of people to risk and have more severe outcomes than not-SR crashes on the same low speed roads. Copyright © 2016 Elsevier Ltd. All rights reserved.
Cost of Crashes Related to Road Conditions, United States, 2006
Zaloshnja, Eduard; Miller, Ted R.
2009-01-01
This is the first study to estimate the cost of crashes related to road conditions in the U.S. To model the probability that road conditions contributed to the involvement of a vehicle in the crash, we used 2000–03 Large Truck Crash Causation Study (LTCCS) data, the only dataset that provides detailed information whether road conditions contributed to crash occurrence. We applied the logistic regression results to a costed national crash dataset in order to calculate the probability that road conditions contributed to the involvement of a vehicle in each crash. In crashes where someone was moderately to seriously injured (AIS-2-6) in a vehicle that harmfully impacted a large tree or medium or large non-breakaway pole, or if the first harmful event was collision with a bridge, we changed the calculated probability of being road-related to 1. We used the state distribution of costs of fatal crashes where road conditions contributed to crash occurrence or severity to estimate the respective state distribution of non-fatal crash costs. The estimated comprehensive cost of traffic crashes where road conditions contributed to crash occurrence or severity was $217.5 billion in 2006. This represented 43.6% of the total comprehensive crash cost. The large share of crash costs related to road design and conditions underlines the importance of these factors in highway safety. Road conditions are largely controllable. Road maintenance and upgrading can prevent crashes and reduce injury severity. PMID:20184840
The impact of Michigan's text messaging restriction on motor vehicle crashes.
Ehsani, Johnathon P; Bingham, C Raymond; Ionides, Edward; Childers, David
2014-05-01
The purpose of this study was to determine the effects of Michigan's universal text messaging restriction (effective July 2010) across different age groups of drivers and crash severities. Changes in monthly crash rates and crash trends per 10,000 licensed drivers aged 16, 17, 18, 19, 20-24, and 25-50 years were estimated using time series analysis for three levels of crash severity: (1) fatal/disabling injury; (2) nondisabling injury; and (3) possible injury/property damage only (PDO) crashes for the period 2005-2012. Analyses were adjusted for crash rates of drivers' aged 65-99 years, Michigan's unemployment rate, and gasoline prices. After the introduction of the texting restriction, significant increases were observed in crash rates and monthly trends in fatal/disabling injury crashes and nondisabling injury crashes, and significant decreases in possible injury/PDO crashes. The magnitude of the effects where significant changes were observed was small. The introduction of the texting restriction was not associated with a reduction in crash rates or trends in severe crash types. On the contrary, small increases in the most severe crash types (fatal/disabling and nondisabling injury) and small decreases in the least severe crash types (possible injury/PDO) were observed. These findings extend the literature on the effects of cell phone restrictions by examining the effects of the restriction on newly licensed adolescent drivers and adult drivers separately by crash severity. Published by Elsevier Inc.
Chung, Younshik
2018-02-01
In-vehicle recording devices have enabled recent changes in methodological paradigms for traffic safety research. Such devices include event data recorders (EDRs), vehicle black boxes (VBBs), and various sensors used in naturalistic driving studies (NDSs). These technologies may help improve the validity of models used to assess impacts on traffic safety. The objective of this study is to analyze the injury severity in taxi-pedestrian crashes using the accurate crash data from VBBs, such as the time-to-collision (TTC), speed, angle, and region of the crash. VBB data from a two-year period (2010-2011) were collected from taxis operating in Incheon, South Korea. An ordered probit model was then applied to analyze the injury severity in crashes. Five variables were found to have a greater effect on injury severity: crash speed, crashes in no-median sections, crashes where the secondary impact object of pedestrians was the crash vehicle, crashes where the third impact object of pedestrians was another moving vehicle, and crashes where the third impact region of pedestrians was their head. However, injuries were less severe in crashes where the first impact region on the pedestrian was their leg, crashes with the car moving in a straight line, and crashes involving junior high school students. Copyright © 2017 Elsevier Ltd. All rights reserved.
McDonald, Catherine C; Curry, Allison E; Kandadai, Venk; Sommers, Marilyn S; Winston, Flaura K
2014-11-01
Motor vehicle crashes are the leading cause of death and acquired disability during the first four decades of life. While teen drivers have the highest crash risk, few studies examine the similarities and differences in teen and adult driver crashes. We aimed to: (1) identify and compare the most frequent crash scenarios-integrated information on a vehicle's movement prior to crash, immediate pre-crash event, and crash configuration-for teen and adult drivers involved in serious crashes, and (2) for the most frequent scenarios, explore whether the distribution of driver critical errors differed for teens and adult drivers. We analyzed data from the National Motor Vehicle Crash Causation Survey, a nationally representative study of serious crashes conducted by the U.S. National Highway Traffic Safety Administration from 2005 to 2007. Our sample included 642 16- to 19-year-old and 1167 35- to 54-year-old crash-involved drivers (weighted n=296,482 and 439,356, respectively) who made a critical error that led to their crash's critical pre-crash event (i.e., event that made the crash inevitable). We estimated prevalence ratios (PR) and 95% confidence intervals (CI) to compare the relative frequency of crash scenarios and driver critical errors. The top five crash scenarios among teen drivers, accounting for 37.3% of their crashes, included: (1) going straight, other vehicle stopped, rear end; (2) stopped in traffic lane, turning left at intersection, turn into path of other vehicle; (3) negotiating curve, off right edge of road, right roadside departure; (4) going straight, off right edge of road, right roadside departure; and (5) stopped in lane, turning left at intersection, turn across path of other vehicle. The top five crash scenarios among adult drivers, accounting for 33.9% of their crashes, included the same scenarios as the teen drivers with the exception of scenario (3) and the addition of going straight, crossing over an intersection, and continuing on a straight path. For two scenarios ((1) and (3) above), teens were more likely than adults to make a critical decision error (e.g., traveling too fast for conditions). Our findings indicate that among those who make a driver critical error in a serious crash, there are few differences in the scenarios or critical driver errors for teen and adult drivers. Copyright © 2014 Elsevier Ltd. All rights reserved.
Costs of Alcohol-Involved Crashes, United States, 2010
Zaloshnja, Eduard; Miller, Ted R.; Blincoe, Lawrence J.
2013-01-01
This paper estimates total and unit costs of alcohol-involved crashes in the U.S. in 2010. With methods from earlier studies, we estimated costs per crash survivor by MAIS, body part, and fracture/dislocation involvement. We multiplied them times 2010 crash incidence estimates from NHTSA data sets, with adjustments for underreporting of crashes and their alcohol involvement. The unit costs are lifetime costs discounted at 3%. To develop medical costs, we combined 2008 Health Care Utilization Program national data for hospitalizations and ED visits of crash survivors with prior estimates of post-discharge costs. Productivity losses drew on Current Population Survey and American Time Use Survey data. Quality of life losses came from a 2011 AAAM paper and property damage from insurance data. We built a hybrid incidence file comprised of 2008–2010 and 1984–86 NHTSA crash surveillance data, weighted with 2010 General Estimates System weights. Fatality data came from the 2010 FARS. An estimated 12% of 2010 crashes but only 0.9% of miles driven were alcohol-involved (BAC > .05). Alcohol-involved crashes cost an estimated $125 billion. That is 22.5% of the societal cost of all crashes. Alcohol-attributable crashes accounted for an estimated 22.5% of US auto liability insurance payments. Alcohol-involved crashes cost $0.86 per drink. Above the US BAC limit of .08, crash costs were $8.37 per mile driven; 1 in 788 trips resulted in a crash and 1 in 1,016 trips in an arrest. Unit costs for crash survivors by severity are higher for impaired driving than for other crashes. That suggests national aggregate impaired driving cost estimates in other countries are substantial underestimates if they are based on all-crash unit costs. PMID:24406941
Chen, Cong; Zhang, Guohui; Liu, Xiaoyue Cathy; Ci, Yusheng; Huang, Helai; Ma, Jianming; Chen, Yanyan; Guan, Hongzhi
2016-12-01
There is a high potential of severe injury outcomes in traffic crashes on rural interstate highways due to the significant amount of high speed traffic on these corridors. Hierarchical Bayesian models are capable of incorporating between-crash variance and within-crash correlations into traffic crash data analysis and are increasingly utilized in traffic crash severity analysis. This paper applies a hierarchical Bayesian logistic model to examine the significant factors at crash and vehicle/driver levels and their heterogeneous impacts on driver injury severity in rural interstate highway crashes. Analysis results indicate that the majority of the total variance is induced by the between-crash variance, showing the appropriateness of the utilized hierarchical modeling approach. Three crash-level variables and six vehicle/driver-level variables are found significant in predicting driver injury severities: road curve, maximum vehicle damage in a crash, number of vehicles in a crash, wet road surface, vehicle type, driver age, driver gender, driver seatbelt use and driver alcohol or drug involvement. Among these variables, road curve, functional and disabled vehicle damage in crash, single-vehicle crashes, female drivers, senior drivers, motorcycles and driver alcohol or drug involvement tend to increase the odds of drivers being incapably injured or killed in rural interstate crashes, while wet road surface, male drivers and driver seatbelt use are more likely to decrease the probability of severe driver injuries. The developed methodology and estimation results provide insightful understanding of the internal mechanism of rural interstate crashes and beneficial references for developing effective countermeasures for rural interstate crash prevention. Copyright © 2016 Elsevier Ltd. All rights reserved.
Subaiya, Saleena; Hogg, Euan; Roberts, Ian
2011-02-03
All sectors of the economy, including the health research sector, must reduce their carbon emissions. The UK National Institute for Health Research has recently prepared guidelines on how to minimize the carbon footprint of research. We compare the carbon emissions from two international clinical trials in order to identify where emissions reductions can be made. We conducted a carbon audit of two clinical trials (the CRASH-1 and CRASH-2 trials), quantifying the carbon dioxide emissions produced over a one-year audit period. Carbon emissions arising from the coordination centre, freight delivery, trial-related travel and commuting were calculated and compared. The total emissions in carbon dioxide equivalents during the one-year audit period were 181.3 tonnes for CRASH-1 and 108.2 tonnes for CRASH-2. In total, CRASH-1 emitted 924.6 tonnes of carbon dioxide equivalents compared with 508.5 tonnes for CRASH-2. The CRASH-1 trial recruited 10,008 patients over 5.1 years, corresponding to 92 kg of carbon dioxide per randomized patient. The CRASH-2 trial recruited 20,211 patients over 4.7 years, corresponding to 25 kg of carbon dioxide per randomized patient. The largest contributor to emissions in CRASH-1 was freight delivery of trial materials (86.0 tonnes, 48% of total emissions), whereas the largest contributor in CRASH-2 was energy use by the trial coordination centre (54.6 tonnes, 30% of total emissions). Faster patient recruitment in the CRASH-2 trial largely accounted for its greatly increased carbon efficiency in terms of emissions per randomized patient. Lighter trial materials and web-based data entry also contributed to the overall lower carbon emissions in CRASH-2 as compared to CRASH-1. CRASH-1: ISRCTN74459797CRASH-2: ISRCTN86750102.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Carter, R.J.; Barickman, F.S.; Spelt, P.F.
1998-01-01
A two-phase, multi-year research program entitled ``development of a portable driver performance data acquisition system for human factors research`` was recently completed. The primary objective of the project was to develop a portable data acquisition system for crash avoidance research (DASCAR) that will allow drive performance data to be collected using a large variety of vehicle types and that would be capable of being installed on a given vehicle type within a relatively short-time frame. During phase 1 a feasibility study for designing and fabricating DASCAR was conducted. In phase 2 of the research DASCAR was actually developed and validated.more » This technical memorandum documents the results from the feasibility study. It is subdivided into three volumes. Volume one (this report) addresses the last five items in the phase 1 research and the first issue in the second phase of the project. Volumes two and three present the related appendices, and the design specifications developed for DASCAR respectively. The six tasks were oriented toward: identifying parameters and measures; identifying analysis tools and methods; identifying measurement techniques and state-of-the-art hardware and software; developing design requirements and specifications; determining the cost of one or more copies of the proposed data acquisition system; and designing a development plan and constructing DASCAR. This report also covers: the background to the program; the requirements for the project; micro camera testing; heat load calculations for the DASCAR instrumentation package in automobile trunks; phase 2 of the research; the DASCAR hardware and software delivered to the National Highway Traffic Safety Administration; and crash avoidance problems that can be addressed by DASCAR.« less
The Pattern of Road Traffic Crashes in South East Iran
Rad, Mahdieh; Martiniuk, Alexandra LC.; Ansari-Moghaddam, Alireza; Mohammadi, Mahdi; Rashedi, Fariborz; Ghasemi, Ardavan
2016-01-01
Background: In the present study, the epidemiologic aspects of road traffic crashes in South East of Iran are described. Methods: This cross-sectional study included the profile of 2398 motor vehicle crashes recorded in the police office in one Year in South East of Iran. Data collected included: demographics, the type of crash, type of involved vehicle, location of crash and factors contributing to the crash. Descriptive statistics were used for data analysis. Results: Collisions with other vehicles or objects contributed the highest proportion (62.4%) of motor vehicle crashes. Human factors including careless driving, violating traffic laws, speeding, and sleep deprivation/fatigue were the most important causal factors accounting for 90% of road crashes. Data shows that 41% of drivers were not using a seat belt at the time of crash. One- third of the crashes resulted in injury (25%) or death (5%). Conclusions: Reckless driving such as speeding and violation of traffic laws are major risk factors for crashes in the South East of Iran. This highlights the need for education along with traffic law enforcement to reduce motor vehicle crashes in future. PMID:27157159
The Pattern of Road Traffic Crashes in South East Iran.
Rad, Mahdieh; Martiniuk, Alexandra Lc; Ansari-Moghaddam, Alireza; Mohammadi, Mahdi; Rashedi, Fariborz; Ghasemi, Ardavan
2016-09-01
In the present study, the epidemiologic aspects of road traffic crashes in South East of Iran are described. This cross-sectional study included the profile of 2398 motor vehicle crashes recorded in the police office in one Year in South East of Iran. Data collected included: demographics, the type of crash, type of involved vehicle, location of crash and factors contributing to the crash. Descriptive statistics were used for data analysis. Collisions with other vehicles or objects contributed the highest proportion (62.4%) of motor vehicle crashes. Human factors including careless driving, violating traffic laws, speeding, and sleep deprivation/fatigue were the most important causal factors accounting for 90% of road crashes. Data shows that 41% of drivers were not using a seat belt at the time of crash. One- third of the crashes resulted in injury (25%) or death (5%). Reckless driving such as speeding and violation of traffic laws are major risk factors for crashes in the South East of Iran. This highlights the need for education along with traffic law enforcement to reduce motor vehicle crashes in future.
Phase I of the Near Term Hybrid Passenger Vehicle Development Program. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1980-10-01
The results of Phase I of the Near-Term Hybrid Vehicle Program are summarized. This phase of the program ws a study leading to the preliminary design of a 5-passenger hybrid vehicle utilizing two energy sources (electricity and gasoline/diesel fuel) to minimize petroleum usage on a fleet basis. This report presents the following: overall summary of the Phase I activity; summary of the individual tasks; summary of the hybrid vehicle design; summary of the alternative design options; summary of the computer simulations; summary of the economic analysis; summary of the maintenance and reliability considerations; summary of the design for crash safety;more » and bibliography.« less
Yang, Hongtai; Cherry, Christopher R; Su, Fan; Ling, Ziwen; Pannell, Zane; Li, Yanlai; Fu, Zhijian
2018-05-25
Unreported minor crashes have importance as a surrogate for more serious crashes that require infrastructure, education, and enforcement strategies; and they still inflict damages. To study factors that influence underreporting, cause, and severity of minor crashes; a survey was performed in Kunming and Beijing to collect self-reported personal characteristics and crash history data of the three major urban road users in China: automobile drivers, bicycle riders and electric bike (e-bike) riders. Underreporting rates of automobile to automobile, automobile to non-motorized vehicle, and non-motorized vehicle to non-motorized vehicle crashes are 56%, 77% and 94%, respectively. Minor crashes with higher reported injury severity levels are more likely to be reported. E-bike riders without a driver's license are more likely to cause crashes. Licensing and education could be an effective way to reduce their crashes. The party that is not at fault in a crash is more likely to sustain high level of injury.
Selection of comparison crash types for quasi-induced exposure risk estimation.
Keall, Michael; Newstead, Stuart
2009-03-01
The objective of this study was to find a comparison crash type that best represented exposure on the road and to identify situations where the induced exposure risk estimates were likely to be biased. Counts of crash involvements were compared with distance driven estimates derived from a register of licensed motor vehicles to identify the most appropriate comparison crash type for induced exposure estimation, which is the crash type whose counts are best correlated with vehicle distance driven. The best sets of comparison crashes for disaggregations by driver age and gender and vehicle type were found to be multi-vehicle crashes in which the vehicle was damaged in the rear or multi-vehicle crashes in which the driver was adjudged to be not at fault. Likely bias of induced exposure risk estimates was identified, even for these best sets of comparison crashes, according to vehicle size (with large vehicles underrepresented) and owner age and gender (with young owners and female owners overrepresented). This research identified some important features of crash occurrence useful for making choices of comparison crash types when controlling for exposure. None of the crash types considered as comparison crashes performed perfectly. Even the crash types that seemed to best reflect exposure on the road still appeared to over- or underestimate distance driven according to owner age group, gender, and vehicle size.
Death and injury in aerial spraying: pre-crash, crash, and post-crash prevention strategies.
Richter, E D; Gordon, M; Halamish, M; Gribetz, B
1981-01-01
To prevent crash-related death and injury among spray pilots, a program including pre-crash, crash and post-crash stages of intervention for aircraft, physical environment, and pilots and ground crews was proposed in accordance with a matrix of options derived from road crash epidemiology. In addition to the dangers of fixed obstacles, low-altitude runs, and heavy work schedules, work hazards included combined exposures to noise, vibration, G forces, heat stress, pesticides, and dehydration. Together, these exposures were believed to have produced slight, but crucial decreases in pilot performance, alertness and skill. For aircraft, the major pre-crash measure was cockpit air cooling, with filter technologies to prevent in-flight pesticide exposure. Crash and post-crash design changes to reduce energy transfers to the pilot's body (thermal, kinetic) were the most important recommendations, because absolute prevention of the crash event was unlikely. For the environment, pre-crash recommendations included marking fixed obstacles, such as power and telephone lines, but preferably their elimination. Other measures included drainage pits with sodium hydroxide points to neutralize parathion and prevent dispersion of parathion-containing mists. Pilot pre-crash measures (more fluid intake, biological monitoring--EMG, urinary alkyl phosphate, cholinesterase testing) required special organizational arrangements. Systematic application of options from the foregoing matrix suggest that the high risk of death and injury from aerial spraying is unnecessary.
Traffic crash statistics report, 1998
DOT National Transportation Integrated Search
1999-01-01
The information contained in this Traffic Crash Facts booklet is extracted from law : enforcement agency long-form reports of traffic crashes. A law enforcement officer must submit a : long-form crash report when investigating: : Motor vehicle crashe...
Traffic crash statistics report, 1995
DOT National Transportation Integrated Search
1996-01-01
The information contained in this Traffic Crash Facts booklet is extracted from law enforcement : agency long-form reports of traffic crashes. A law enforcement officer must submit a long-form crash report : when investigating: : Motor vehicle crashe...
Traffic crash statistics report, 1996
DOT National Transportation Integrated Search
1997-11-01
The information contained in this Traffic Crash Facts booklet is extracted from law enforcement : agency long-form reports of traffic crashes. A law enforcement officer must submit a long-form crash report : when investigating: : Motor vehicle crashe...
Traffic crash statistics report, 1994
DOT National Transportation Integrated Search
1995-01-01
The information contained in this Traffic Crash Data booklet is extracted from law enforcement : agency long-form reports of traffic crashes. A law enforcement officer must submit a long-form crash report : when investigating: : Motor vehicle crashes...
Traffic crash statistics report, 2004
DOT National Transportation Integrated Search
2005-01-01
The information contained in this Traffic Crash Data booklet is extracted from law enforcement : agency long-form reports of traffic crashes. A law enforcement officer must submit a long-form crash report : when investigating: : Motor vehicle crashes...
Traffic crash statistics report, 1997
DOT National Transportation Integrated Search
1998-01-01
The information contained in this Traffic Crash Facts booklet is extracted from law enforcement agency : long-form reports of traffic crashes. A law enforcement officer must submit a long-form crash report when : investigating: : Motor vehicle crashe...
Wu, Kun-Feng; Donnell, Eric T; Aguero-Valverde, Jonathan
2014-06-01
To approach the goal of "Toward Zero Deaths," there is a need to develop an analysis paradigm to better understand the effects of a countermeasure on reducing the number of severe crashes. One of the goals in traffic safety research is to search for an effective treatment to reduce fatal and major injury crashes, referred to as severe crashes. To achieve this goal, the selection of promising countermeasures is of utmost importance, and relies on the effectiveness of candidate countermeasures in reducing severe crashes. Although it is important to precisely evaluate the effectiveness of candidate countermeasures in reducing the number of severe crashes at a site, the current state-of-the-practice often leads to biased estimates. While there have been a few advanced statistical models developed to mitigate the problem in practice, these models are computationally difficult to estimate because severe crashes are dispersed spatially and temporally, and cannot be integrated into the Highway Safety Manual framework, which develops a series of safety performance functions and crash modification factors to predict the number of crashes. Crash severity outcomes are generally integrated into the Highway Safety Manual using deterministic distributions rather than statistical models. Accounting for the variability in crash severity as a function geometric design, traffic flow, and other roadway and roadside features is afforded by estimating statistical models. Therefore, there is a need to develop a new analysis paradigm to resolve the limitations in the current Highway Safety Manual methods. We propose an approach which decomposes the severe crash frequency into a function of the change in the total number of crashes and the probability of a crash becoming a severe crash before and after a countermeasure is implemented. We tested this approach by evaluating the effectiveness of shoulder rumble strips on reducing the number of severe crashes. A total of 310 segments that have had shoulder rumble strips installed during 2002-2009 are included in the analysis. It was found that shoulder rumble strips reduce the total number of crashes, but have no statistically significant effect on reducing the probability of a severe crash outcome. Copyright © 2014 Elsevier Ltd. All rights reserved.
Crash risk factors for interstate large trucks in North Carolina.
Teoh, Eric R; Carter, Daniel L; Smith, Sarah; McCartt, Anne T
2017-09-01
Provide an updated examination of risk factors for large truck involvements in crashes resulting in injury or death. A matched case-control study was conducted in North Carolina of large trucks operated by interstate carriers. Cases were defined as trucks involved in crashes resulting in fatal or non-fatal injury, and one control truck was matched on the basis of location, weekday, time of day, and truck type. The matched-pair odds ratio provided an estimate of the effect of various driver, vehicle, or carrier factors. Out-of-service (OOS) brake violations tripled the risk of crashing; any OOS vehicle defect increased crash risk by 362%. Higher historical crash rates (fatal, injury, or all crashes) of the carrier were associated with increased risk of crashing. Operating on a short-haul exemption increased crash risk by 383%. Antilock braking systems reduced crash risk by 65%. All of these results were statistically significant at the 95% confidence level. Other safety technologies also showed estimated benefits, although not statistically significant. With the exception of the finding that short-haul exemption is associated with increased crash risk, results largely bolster what is currently known about large truck crash risk and reinforce current enforcement practices. Results also suggest vehicle safety technologies can be important in lowering crash risk. This means that as safety technology continues to penetrate the fleet, whether from voluntary usage or government mandates, reductions in large truck crashes may be achieved. Practical application: Results imply that increased enforcement and use of crash avoidance technologies can improve the large truck crash problem. Copyright © 2017 National Safety Council and Elsevier Ltd. All rights reserved.
DOT National Transportation Integrated Search
1997-01-01
Indiana Crash Facts 1997...is the fifth annual publication : of Indiana Crash Facts. This year significant changes have been made : to the book, including the consolidation of the Alcohol Crash Facts and : the Crash Facts book into one publication. A...
DOT National Transportation Integrated Search
1996-01-01
According to Indiana State Police Crash Reports, : 221,465 traffic crashes were reported in Indiana : during 1996 (Table 1). Of these, 870 were fatal : crashes in which 982 people died. There were an : additional 52,058 personal injury crashes and a ...
The trend of road traffic crashes at urban signalised intersection
NASA Astrophysics Data System (ADS)
Farhana Nasarrudin, Nurul; Razelan, Intan Suhana Mohd
2018-04-01
Road traffic crash is one of the main contributing factors for deaths in the world. Intersection is listed as the second road type which road crashes occurred frequently. Hence, the traffic light was installed to minimise the road crashes at intersection. However, the crashes are still occurring and arising. The objective of this study was to exhibit the trend of road crashes at the signalised intersections. The data of road crashes for the past 6 years were analysed using descriptive analysis. The results showed that the road traffic crashes at three- and four-legged signalised intersection recorded the increasing trend. In conclusion, this finding shows that the road traffic crashes for these types of signalised intersection in Malaysia is rising. It is also one the contributors to the increasing number of crashes in Malaysia. This finding will encourage the local authority to conduct awareness programs on the safety at the signalised intersection.
Effects of blind spot monitoring systems on police-reported lane-change crashes.
Cicchino, Jessica B
2018-06-21
To examine the effectiveness of blind spot monitoring systems in preventing police-reported lane-change crashes. Poisson regression was used to compare crash involvement rates per insured vehicle year in police-reported lane-change crashes in 26 U.S. states during 2009-2015 between vehicles with blind spot monitoring and the same vehicle models without the optional system, controlling for other factors that can affect crash risk. Crash involvement rates in lane-change crashes were 14% lower (95% confidence limits -24% to -2%) among vehicles with blind spot monitoring than those without. Blind spot monitoring systems are effective in preventing police-reported lane-change crashes when considering crashes of all severities. If every U.S. vehicle in 2015 were equipped with blind spot monitoring that performed like the study systems, it is estimated that about 50,000 crashes could have been prevented.
Identifying work-related motor vehicle crashes in multiple databases.
Thomas, Andrea M; Thygerson, Steven M; Merrill, Ray M; Cook, Lawrence J
2012-01-01
To compare and estimate the magnitude of work-related motor vehicle crashes in Utah using 2 probabilistically linked statewide databases. Data from 2006 and 2007 motor vehicle crash and hospital databases were joined through probabilistic linkage. Summary statistics and capture-recapture were used to describe occupants injured in work-related motor vehicle crashes and estimate the size of this population. There were 1597 occupants in the motor vehicle crash database and 1673 patients in the hospital database identified as being in a work-related motor vehicle crash. We identified 1443 occupants with at least one record from either the motor vehicle crash or hospital database indicating work-relatedness that linked to any record in the opposing database. We found that 38.7 percent of occupants injured in work-related motor vehicle crashes identified in the motor vehicle crash database did not have a primary payer code of workers' compensation in the hospital database and 40.0 percent of patients injured in work-related motor vehicle crashes identified in the hospital database did not meet our definition of a work-related motor vehicle crash in the motor vehicle crash database. Depending on how occupants injured in work-related motor crashes are identified, we estimate the population to be between 1852 and 8492 in Utah for the years 2006 and 2007. Research on single databases may lead to biased interpretations of work-related motor vehicle crashes. Combining 2 population based databases may still result in an underestimate of the magnitude of work-related motor vehicle crashes. Improved coding of work-related incidents is needed in current databases.
Ito, Daisuke; Hayakawa, Kosei; Kondo, Yuma; Mizuno, Koji; Thomson, Robert; Piccinini, Giulio Bianchi; Hosokawa, Naruyuki
2018-08-01
Analyzing a crash using driving recorder data makes it possible to objectively examine factors contributing to the occurrence of the crash. In this study, car-to-cyclist crashes and near crashes recorded on cars equipped with advanced driving recorders were compared with each other in order to examine the factors that differentiate near crashes from crashes, as well as identify the causes of the crashes. Focusing on cases where the car and cyclist approached each other perpendicularly, the differences in the car's and cyclist's parameters such as velocity, distance and avoidance behavior were analyzed. The results show that car-to-cyclist crashes would not be avoidable when the car approaching the cyclist enters an area where the average deceleration required to stop the car is more than 0.45 G (4.4 m/s 2 ). In order for this situation to occur, there are two types of cyclist crash scenarios. In the first scenario, the delay in the drivers' reaction in activating the brakes is the main factor responsible for the crash. In this scenario, time-to-collision when the cyclist first appears in the video is more than 2.0 s. In the second scenario, the sudden appearance of a cyclist from behind an obstacle on the street is the factor responsible for the crash. In this case, the time-to-collision is less than 1.2 s, and the crash cannot be avoided even if the driver exhibited avoidance maneuvers. Copyright © 2018 Elsevier Ltd. All rights reserved.
Risk and type of crash among young drivers by rurality of residence: findings from the DRIVE Study.
Chen, H Y; Ivers, R Q; Martiniuk, A L C; Boufous, S; Senserrick, T; Woodward, M; Stevenson, M; Williamson, A; Norton, R
2009-07-01
Most previous literature on urban/rural differences in road crashes has a primary focus on severe injuries or deaths, which may be largely explained by variations of medical resources. Little has been reported on police-reported crashes by geographical location, or crash type and severity, especially among young drivers. DRIVE is a prospective cohort study of 20,822 drivers aged 17-24 in NSW, Australia. Information on risk factors was collected via online questionnaire and subsequently linked to police-reported crashes. Poisson regression was used to analyse risk of various crash types by three levels of rurality of residence: urban, regional (country towns and surrounds) and rural. Compared to urban drivers, risk of crash decreased with increasing rurality (regional adjusted RR: 0.7, 95% CI 0.6-0.9; rural adjusted RR: 0.5, 95% CI 0.3-0.7). Among those who crashed, risk of injurious crash did not differ by geographic location; however, regional and rural drivers had significantly higher risk of a single versus multiple vehicle crash (regional adjusted RR 1.8, 95% CI 1.3-2.5; rural adjusted RR: 2.0, 95% CI 1.1-3.6), which was explained by speeding involvement and road alignment at the time or site of crash. Although young urban drivers have a higher crash risk overall, rural and regional residents have increased risk of a single vehicle crash. Interventions to reduce single vehicle crashes should aim to address key issues affecting such crashes, including speeding and specific aspects of road geometry.
DOT National Transportation Integrated Search
2014-04-01
Through the analysis of national crash databases from the National Highway Traffic Safety Administration, pre-crash scenarios are identified, prioritized, and described for the development of objective tests for pedestrian crash avoidance/mitigation ...
The Stock Market Crashes of 1929 and 1987: Linking History and Personal Finance Education
ERIC Educational Resources Information Center
Lopus, Jane S.
2005-01-01
This article discusses two twentieth-century stock market crashes: the crash of 1929 and the crash of 1987. When this material is presented to students, they see important parallels between the two historical events. But despite remarkable similarities in the severity and many other aspects of the two crashes, the crash of 1929 was followed by the…
Changes in fatal and nonfatal crash rates on a toll highway.
Doege, T C; Levy, P S
1976-02-01
Rates of crashes, crashes with injuries, and crashes with fatalities were lower during the 6 months of March 1-August 31, 1974, following a 5-15 mph (8-24 kph) decrease in speed limits on the Illinois Tollway, than the corresponding rates for any of the 6 preceding years, 1968-1973. During the same months of 1968-1974, rates of crashes and of crashes with injuries showed peaks without consistent trends, but rates and percentages of fatal crashes decreased. The data agree with the hypothesis that reducing speed limits on toll roads may lead to substantial reductions in rate of crashes and injuries.
The effect of crash experience on changes in risk taking among urban and rural young people.
Lin, Mau-Roung; Huang, Wenzheng; Hwang, Hei-Fen; Wu, Hong-Dar Isaac; Yen, Lee-Lan
2004-03-01
A 20-month prospective study was conducted to investigate the effect of motorcycle crash experience on changes in risk taking among 2514 urban and 2304 rural students in Taiwan. Risk taking was assessed using a 14-item self-administered questionnaire at the beginning and end of the study. A risk-taking score for each student at the initial and the last follow-up assessments was generated from adding up points across all 14 items. For exposure variables, the study documented past motorcycle crash history at the initial assessment and collected detailed information about any motorcycle crash involvement that occurred during the study period. A general linear mixed model was applied to assess the effects of prior and recent crash involvements on the path of risk-taking behavior. The results show that at the initial assessment, students with crash experience had higher risk-taking levels than those without crash experience. However, crash experience, irregardless of whether it was measured in terms of crash history prior to the study, crash frequency, time elapsed since the last crash, or crash severity, did not significantly change the risk-taking path among students, even though its effect differed between urban and rural areas.
Traffic environment and demographic factors affecting impaired driving and crashes
Romano, Eduardo O.; Peck, Raymond C.; Voas, Robert B.
2012-01-01
Introduction Data availability has forced researchers to examine separately the role of alcohol among drivers who crashed and drivers who did not crash. Such a separation fails to account fully for the transition from impaired driving to an alcohol-related crash. Method In this study, we analyzed recent data to investigate how traffic-related environments, conditions, and drivers’ demographics shape the likelihood of a driver being either involved in a crash (alcohol impaired or not) or not involved in a crash (alcohol impaired or not). Our data, from a recent case–control study, included a comprehensive sampling of the drivers in nonfatal crashes and a matched set of comparison drivers in two U.S. locations. Multinomial logistic regression was applied to investigate the likelihood that a driver would crash or would not crash, either with a blood alcohol concentration (BAC)=.00 or with a BAC≥.05. Conclusions To our knowledge, this study is the first to examine how different driver characteristics and environmental factors simultaneously contribute to alcohol use by crash-involved and non-crash-involved drivers. This effort calls attention to the need for research on the simultaneous roles played by all the factors that may contribute to motor vehicle crashes. PMID:22385743
Reporting on cyclist crashes in Australian newspapers.
Boufous, Soufiane; Aboss, Ahmad; Montgomery, Victoria
2016-10-01
To assess information on cyclist crashes reported in Australian newspapers. The Factiva news archive was searched for articles on cyclist crashes published in major Australian newspapers between 2010 and 2013. Information on the circumstances of cyclist crashes were extracted and coded. A total of 160 cyclist crashes were covered by 198 newspaper articles, with 44% of crashes resulting in cyclist fatalities. Crashes reported by more than one newspaper were more likely to involve public figures or protracted court cases. Individual characteristics of cyclists as well as the location of the crash were reported for more than 80% of crashes. The road user at fault was reported for more than half of crashes. In contrast, information on helmet use, alcohol and cycling lanes was mentioned for only about 10% of crashes. Fewer than one in five articles mentioned prevention strategies including education campaigns, legislative and infrastructure changes. Australian newspapers tend to focus on the most dramatic and more 'newsworthy' aspects of cyclist crashes. Cycling advocates need to work with journalists to improve the quality of this coverage. Better communication between cycling advocates and journalists is likely to have a positive impact on the safety and the uptake of cycling in the community. © 2016 Public Health Association of Australia.
2011-01-01
Background All sectors of the economy, including the health research sector, must reduce their carbon emissions. The UK National Institute for Health Research has recently prepared guidelines on how to minimize the carbon footprint of research. We compare the carbon emissions from two international clinical trials in order to identify where emissions reductions can be made. Methods We conducted a carbon audit of two clinical trials (the CRASH-1 and CRASH-2 trials), quantifying the carbon dioxide emissions produced over a one-year audit period. Carbon emissions arising from the coordination centre, freight delivery, trial-related travel and commuting were calculated and compared. Results The total emissions in carbon dioxide equivalents during the one-year audit period were 181.3 tonnes for CRASH-1 and 108.2 tonnes for CRASH-2. In total, CRASH-1 emitted 924.6 tonnes of carbon dioxide equivalents compared with 508.5 tonnes for CRASH-2. The CRASH-1 trial recruited 10,008 patients over 5.1 years, corresponding to 92 kg of carbon dioxide per randomized patient. The CRASH-2 trial recruited 20,211 patients over 4.7 years, corresponding to 25 kg of carbon dioxide per randomized patient. The largest contributor to emissions in CRASH-1 was freight delivery of trial materials (86.0 tonnes, 48% of total emissions), whereas the largest contributor in CRASH-2 was energy use by the trial coordination centre (54.6 tonnes, 30% of total emissions). Conclusions Faster patient recruitment in the CRASH-2 trial largely accounted for its greatly increased carbon efficiency in terms of emissions per randomized patient. Lighter trial materials and web-based data entry also contributed to the overall lower carbon emissions in CRASH-2 as compared to CRASH-1. Trial Registration Numbers CRASH-1: ISRCTN74459797 CRASH-2: ISRCTN86750102 PMID:21291517
Head-on crashes on two-way interurban roads: a public health concern in road safety.
Olabarria, Marta; Santamariña-Rubio, Elena; Marí-Dell'Olmo, Marc; Gotsens, Mercè; Novoa, Ana M; Borrell, Carme; Pérez, Katherine
2015-09-01
To describe the magnitude and characteristics of crashes and drivers involved in head-on crashes on two-way interurban roads in Spain between 2007 and 2012, and to identify the factors associated with the likelihood of head-on crashes on these roads compared with other types of crash. A cross-sectional study was conducted using the National Crash Register. The dependent variables were head-on crashes with injury (yes/no) and drivers involved in head-on crashes (yes/no). Factors associated with head-on crashes and with being a driver involved in a head-on crash versus other types of crash were studied using a multivariate robust Poisson regression model to estimate proportion ratios (PR) and confidence intervals (95% CI). There were 9,192 head-on crashes on two-way Spanish interurban roads. A total of 15,412 men and 3,862 women drivers were involved. Compared with other types of crash, head-on collisions were more likely on roads 7 m or more wide, on road sections with curves, narrowings or drop changes, on wet or snowy surfaces, and in twilight conditions. Transgressions committed by drivers involved in head-on crashes were driving in the opposite direction and incorrectly overtaking another vehicle. Factors associated with a lower probability of head-on crashes were the existence of medians (PR=0.57; 95%CI: 0.48-0.68) and a paved shoulder of less than 1.5 meters (PR=0.81; 95%CI: 0.77-0.86) or from 1.5 to 2.45 meters (PR=0.90; 95%CI: 0.84-0.96). This study allowed the characterization of crashes and drivers involved in head-on crashes on two-way interurban roads. The lower probability observed on roads with median strips point to these measures as an effective way to reduce these collisions. Copyright © 2014 SESPAS. Published by Elsevier Espana. All rights reserved.
Hosseinpour, Mehdi; Yahaya, Ahmad Shukri; Sadullah, Ahmad Farhan
2014-01-01
Head-on crashes are among the most severe collision types and of great concern to road safety authorities. Therefore, it justifies more efforts to reduce both the frequency and severity of this collision type. To this end, it is necessary to first identify factors associating with the crash occurrence. This can be done by developing crash prediction models that relate crash outcomes to a set of contributing factors. This study intends to identify the factors affecting both the frequency and severity of head-on crashes that occurred on 448 segments of five federal roads in Malaysia. Data on road characteristics and crash history were collected on the study segments during a 4-year period between 2007 and 2010. The frequency of head-on crashes were fitted by developing and comparing seven count-data models including Poisson, standard negative binomial (NB), random-effect negative binomial, hurdle Poisson, hurdle negative binomial, zero-inflated Poisson, and zero-inflated negative binomial models. To model crash severity, a random-effect generalized ordered probit model (REGOPM) was used given a head-on crash had occurred. With respect to the crash frequency, the random-effect negative binomial (RENB) model was found to outperform the other models according to goodness of fit measures. Based on the results of the model, the variables horizontal curvature, terrain type, heavy-vehicle traffic, and access points were found to be positively related to the frequency of head-on crashes, while posted speed limit and shoulder width decreased the crash frequency. With regard to the crash severity, the results of REGOPM showed that horizontal curvature, paved shoulder width, terrain type, and side friction were associated with more severe crashes, whereas land use, access points, and presence of median reduced the probability of severe crashes. Based on the results of this study, some potential countermeasures were proposed to minimize the risk of head-on crashes. Copyright © 2013 Elsevier Ltd. All rights reserved.
Reductions in injury crashes associated with red light camera enforcement in oxnard, california.
Retting, Richard A; Kyrychenko, Sergey Y
2002-11-01
This study estimated the impact of red light camera enforcement on motor vehicle crashes in one of the first US communities to employ such cameras-Oxnard, California. Crash data were analyzed for Oxnard and for 3 comparison cities. Changes in crash frequencies were compared for Oxnard and control cities and for signalized and nonsignalized intersections by means of a generalized linear regression model. Overall, crashes at signalized intersections throughout Oxnard were reduced by 7% and injury crashes were reduced by 29%. Right-angle crashes, those most associated with red light violations, were reduced by 32%; right-angle crashes involving injuries were reduced by 68%. Because red light cameras can be a permanent component of the transportation infrastructure, crash reductions attributed to camera enforcement should be sustainable.
Injury Risk Functions in Frontal Impacts Using Data from Crash Pulse Recorders
Stigson, Helena; Kullgren, Anders; Rosén, Erik
2012-01-01
Knowledge of how crash severity influences injury risk in car crashes is essential in order to create a safe road transport system. Analyses of real-world crashes increase the ability to obtain such knowledge. The aim of this study was to present injury risk functions based on real-world frontal crashes where crash severity was measured with on-board crash pulse recorders. Results from 489 frontal car crashes (26 models of four car makes) with recorded acceleration-time history were analysed. Injury risk functions for restrained front seat occupants were generated for maximum AIS value of two or greater (MAIS2+) using multiple logistic regression. Analytical as well as empirical injury risk was plotted for several crash severity parameters; change of velocity, mean acceleration and peak acceleration. In addition to crash severity, the influence of occupant age and gender was investigated. A strong dependence between injury risk and crash severity was found. The risk curves reflect that small changes in crash severity may have a considerable influence on the risk of injury. Mean acceleration, followed by change of velocity, was found to be the single variable that best explained the risk of being injured (MAIS2+) in a crash. Furthermore, all three crash severity parameters were found to predict injury better than age and gender. However, age was an important factor. The very best model describing MAIS2+ injury risk included delta V supplemented by an interaction term of peak acceleration and age. PMID:23169136
Selecting exposure measures in crash rate prediction for two-lane highway segments.
Qin, Xiao; Ivan, John N; Ravishanker, Nalini
2004-03-01
A critical part of any risk assessment is identifying how to represent exposure to the risk involved. Recent research shows that the relationship between crash count and traffic volume is non-linear; consequently, a simple crash rate computed as the ratio of crash count to volume is not proper for comparing the safety of sites with different traffic volumes. To solve this problem, we describe a new approach for relating traffic volume and crash incidence. Specifically, we disaggregate crashes into four types: (1) single-vehicle, (2) multi-vehicle same direction, (3) multi-vehicle opposite direction, and (4) multi-vehicle intersecting, and define candidate exposure measures for each that we hypothesize will be linear with respect to each crash type. This paper describes initial investigation using crash and physical characteristics data for highway segments in Michigan from the Highway Safety Information System (HSIS). We use zero-inflated-Poisson (ZIP) modeling to estimate models for predicting counts for each of the above crash types as a function of the daily volume, segment length, speed limit and roadway width. We found that the relationship between crashes and the daily volume (AADT) is non-linear and varies by crash type, and is significantly different from the relationship between crashes and segment length for all crash types. Our research will provide information to improve accuracy of crash predictions and, thus, facilitate more meaningful comparison of the safety record of seemingly similar highway locations.
Intersection crash prediction modeling with macro-level data from various geographic units.
Lee, Jaeyoung; Abdel-Aty, Mohamed; Cai, Qing
2017-05-01
There have been great efforts to develop traffic crash prediction models for various types of facilities. The crash models have played a key role to identify crash hotspots and evaluate safety countermeasures. In recent, many macro-level crash prediction models have been developed to incorporate highway safety considerations in the long-term transportation planning process. Although the numerous macro-level studies have found that a variety of demographic and socioeconomic zonal characteristics have substantial effects on traffic safety, few studies have attempted to coalesce micro-level with macro-level data from existing geographic units for estimating crash models. In this study, the authors have developed a series of intersection crash models for total, severe, pedestrian, and bicycle crashes with macro-level data for seven spatial units. The study revealed that the total, severe, and bicycle crash models with ZIP-code tabulation area data performs the best, and the pedestrian crash models with census tract-based data outperforms the competing models. Furthermore, it was uncovered that intersection crash models can be drastically improved by only including random-effects for macro-level entities. Besides, the intersection crash models are even further enhanced by including other macro-level variables. Lastly, the pedestrian and bicycle crash modeling results imply that several macro-level variables (e.g., population density, proportions of specific age group, commuters who walk, or commuters using bicycle, etc.) can be a good surrogate exposure for those crashes. Copyright © 2017 Elsevier Ltd. All rights reserved.
Isaksson-Hellman, Irene; Lindman, Magdalena
2018-02-28
Lane changes, which frequently occur when vehicles travel on major roads, may contribute to critical situations that significantly affect the traffic flow and traffic safety. Thus, knowledge of lane change situations is important for infrastructure improvements as well as for driver support systems and automated driving development projects. The objectives of this study were to evaluate the crash avoidance performance of a lane change driver support system, the Blind Spot Information System (BLIS) in Volvo car models, and to describe the characteristics of lane change crashes by analyzing detailed information from insurance claim reports. An overall evaluation of the safety effect of BLIS was performed by analyzing crash rate differences in lane change situations for cars with and without the optionally mounted BLIS system based on a population of 380,000 insured vehicle years. Further, crashes in which the repair cost of the host vehicle exceeded approximately US$1,250 were selected and compared. Finally, the study examined different precrash factors and crash configurations, using in-depth insurance claims data from representative lane change crash cases including all severity levels in a population of more than 200,000 insured vehicle years. The technology did not significantly reduce the overall number of crashes when all types of lane change crashes and severity levels were considered, though a significant crash-reducing effect of 31% for BLIS cars was found when more severe crashes with a repair cost exceeding US$1,250 were analysed. Cars with the BLIS technology also have a 30% lower claim cost on average for reported lane change crashes, indicating reduced crash severity. When stratifying the data into specific situations, by collecting precrash information in a case-by-case study, the influence of BLIS was indicated to differ for the evaluated situations, although no significant results were found. For example, during general lane change maneuvers (i.e., not while exiting or entering highways or during weaving/merging situations) the crash rate was reduced by 14%, whereas in weaving/merging situations the crash rate increased. The insurance data analyzed provided useful information about real-world lane change crash characteristics by covering collisions in all crash severities and thus revealed information beyond what is available in, for example, data sets of police-reported crashes. This will guide further development of driver support systems. For crashes with repair cost exceeding US$1,250, a significant crash reduction was found, although the technology did not significantly reduce the total number of lane change crashes. An average lower insurance claim cost for cars equipped with the BLIS technology also indicated that the technology contributes to reduced crash severity even if crashes were not totally avoided. Stratifying the data into different lane change crash situations gave indications of the condition-specific performance of the system, even if the results were not statistically significant at the 95% level.
Lee, Chris; Li, Xuancheng
2014-10-01
This study analyzes driver's injury severity in single- and two-vehicle crashes and compares the effects of explanatory variables among various types of crashes. The study identified factors affecting injury severity and their effects on severity levels using 5-year crash records for provincial highways in Ontario, Canada. Considering heteroscedasticity in the effects of explanatory variables on injury severity, the heteroscedastic ordered logit (HOL) models were developed for single- and two-vehicle crashes separately. The results of the models show that there exists heteroscedasticity for young drivers (≤30), safety equipment and ejection in the single-vehicle crash model, and female drivers, safety equipment and head-on collision in the two-vehicle crash models. The results also show that young car drivers have opposite effects between single-car and car-car crashes, and sideswipe crashes have opposite effects between car-car and truck-truck crashes. The study demonstrates that separate HOL models for single-vehicle and different types of two-vehicle crashes can identify differential effects of factors on driver's injury severity. Copyright © 2014 Elsevier Ltd. All rights reserved.
Sebego, Miriam; Naumann, Rebecca B.; Rudd, Rose A.; Voetsch, Karen; Dellinger, Ann M.; Ndlovu, Christopher
2015-01-01
In Botswana, increased development and motorization have brought increased road traffic-related death rates. Between 1981 and 2001, the road traffic-related death rate in Botswana more than tripled. The country has taken several steps over the last several years to address the growing burden of road traffic crashes and particularly to address the burden of alcohol-related crashes. This study examines the impact of the implementation of alcohol and road safety-related policies on crash rates, including overall crash rates, fatal crash rates, and single-vehicle nighttime fatal (SVNF) crash rates, in Botswana from 2004 to 2011. The overall crash rate declined significantly in June 2009 and June 2010, such that the overall crash rate from June 2010 to December 2011 was 22% lower than the overall crash rate from January 2004 to May 2009. Additionally, there were significant declines in average fatal crash and SVNF crash rates in early 2010. Botswana’s recent crash rate reductions occurred during a time when aggressive policies and other activities (e.g., education, enforcement) were implemented to reduce alcohol consumption and improve road safety. While it is unclear which of the policies or activities contributed to these declines and to what extent, these reductions are likely the result of several, combined efforts. PMID:24686164
Sebego, Miriam; Naumann, Rebecca B; Rudd, Rose A; Voetsch, Karen; Dellinger, Ann M; Ndlovu, Christopher
2014-09-01
In Botswana, increased development and motorization have brought increased road traffic-related death rates. Between 1981 and 2001, the road traffic-related death rate in Botswana more than tripled. The country has taken several steps over the last several years to address the growing burden of road traffic crashes and particularly to address the burden of alcohol-related crashes. This study examines the impact of the implementation of alcohol and road safety-related policies on crash rates, including overall crash rates, fatal crash rates, and single-vehicle nighttime fatal (SVNF) crash rates, in Botswana from 2004 to 2011. The overall crash rate declined significantly in June 2009 and June 2010, such that the overall crash rate from June 2010 to December 2011 was 22% lower than the overall crash rate from January 2004 to May 2009. Additionally, there were significant declines in average fatal crash and SVNF crash rates in early 2010. Botswana's recent crash rate reductions occurred during a time when aggressive policies and other activities (e.g., education, enforcement) were implemented to reduce alcohol consumption and improve road safety. While it is unclear which of the policies or activities contributed to these declines and to what extent, these reductions are likely the result of several, combined efforts. Copyright © 2014 Elsevier Ltd. All rights reserved.
Cheng, Wen; Gill, Gurdiljot Singh; Sakrani, Taha; Dasu, Mohan; Zhou, Jiao
2017-11-01
Motorcycle crashes constitute a very high proportion of the overall motor vehicle fatalities in the United States, and many studies have examined the influential factors under various conditions. However, research on the impact of weather conditions on the motorcycle crash severity is not well documented. In this study, we examined the impact of weather conditions on motorcycle crash injuries at four different severity levels using San Francisco motorcycle crash injury data. Five models were developed using Full Bayesian formulation accounting for different correlations commonly seen in crash data and then compared for fitness and performance. Results indicate that the models with serial and severity variations of parameters had superior fit, and the capability of accurate crash prediction. The inferences from the parameter estimates from the five models were: an increase in the air temperature reduced the possibility of a fatal crash but had a reverse impact on crashes of other severity levels; humidity in air was not observed to have a predictable or strong impact on crashes; the occurrence of rainfall decreased the possibility of crashes for all severity levels. Transportation agencies might benefit from the research results to improve road safety by providing motorcyclists with information regarding the risk of certain crash severity levels for special weather conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.
Impact of roadway geometric features on crash severity on rural two-lane highways.
Haghighi, Nima; Liu, Xiaoyue Cathy; Zhang, Guohui; Porter, Richard J
2018-02-01
This study examines the impact of a wide range of roadway geometric features on the severity outcomes of crashes occurred on rural two-lane highways. We argue that crash data have a hierarchical structure which needs to be addressed in modeling procedure. Moreover, most of previous studies ignored the impact of geometric features on crash types when developing crash severity models. We hypothesis that geometric features are more likely to determine crash type, and crash type together with other occupant, environmental and vehicle characteristics determine crash severity outcome. This paper presents an application of multilevel models to successfully capture both hierarchical structure of crash data and indirect impact of geometric features on crash severity. Using data collected in Illinois from 2007 to 2009, multilevel ordered logit model is developed to quantify the impact of geometric features and environmental conditions on crash severity outcome. Analysis results revealed that there is a significant variation in severity outcomes of crashes occurred across segments which verifies the presence of hierarchical structure. Lower risk of severe crashes is found to be associated with the presence of 10-ft lane and/or narrow shoulders, lower roadside hazard rate, higher driveway density, longer barrier length, and shorter barrier offset. The developed multilevel model offers greater consistency with data generating mechanism and can be utilized to evaluate safety effects of geometric design improvement projects. Published by Elsevier Ltd.
Characteristics of cyclist crashes in Italy using latent class analysis and association rule mining
De Angelis, Marco; Marín Puchades, Víctor; Fraboni, Federico; Pietrantoni, Luca
2017-01-01
The factors associated with severity of the bicycle crashes may differ across different bicycle crash patterns. Therefore, it is important to identify distinct bicycle crash patterns with homogeneous attributes. The current study aimed at identifying subgroups of bicycle crashes in Italy and analyzing separately the different bicycle crash types. The present study focused on bicycle crashes that occurred in Italy during the period between 2011 and 2013. We analyzed categorical indicators corresponding to the characteristics of infrastructure (road type, road signage, and location type), road user (i.e., opponent vehicle and cyclist’s maneuver, type of collision, age and gender of the cyclist), vehicle (type of opponent vehicle), and the environmental and time period variables (time of the day, day of the week, season, pavement condition, and weather). To identify homogenous subgroups of bicycle crashes, we used latent class analysis. Using latent class analysis, the bicycle crash data set was segmented into 19 classes, which represents 19 different bicycle crash types. Logistic regression analysis was used to identify the association between class membership and severity of the bicycle crashes. Finally, association rules were conducted for each of the latent classes to uncover the factors associated with an increased likelihood of severity. Association rules highlighted different crash characteristics associated with an increased likelihood of severity for each of the 19 bicycle crash types. PMID:28158296
Huisingh, Carrie; Owsley, Cynthia; Levitan, Emily B; Irvin, Marguerite R; MacLennan, Paul; McGwin, Gerald
2018-05-17
The purpose of this study was to examine the association between secondary task involvement and risk of crash and near-crash involvement among older drivers using naturalistic driving data. Data from drivers aged ≥70 years in the Strategic Highway Research Program (SHRP2) Naturalistic Driving Study database was utilized. The personal vehicle of study participants was equipped with four video cameras enabling recording of the driver and the road environment. Secondary task involvement during a crash or near-crash event was compared to periods of non-crash involvement in a case-crossover study design. Conditional logistic regression was used to generate odds ratios (OR) and 95% confidence intervals (CI). Overall, engaging in any secondary task was not associated with crash (OR=0.94, 95% CI 0.68-1.29) or near-crash (OR=1.08, 95% CI 0.79-1.50) risk. The risk of a major crash event with cell phone use was 3.79 times higher than the risk with no cell phone use (95% CI 1.00-14.37). Other glances into the interior of the vehicle were associated with an increased risk of near-crash involvement (OR=2.55, 95% CI 1.24-5.26). Other distractions external to the vehicle were associated with a decreased risk of crash involvement (OR=0.53, 95% CI 0.30-0.94). Interacting with a passenger and talking/singing were not associated with crash or near-crash risk. Older drivers should avoid any cell phone use and minimize non-driving related eye glances towards the interior of the vehicle while driving. Certain types of events external to the vehicle are associated with a reduced crash risk among older drivers.
Zhang, Guangnan; Li, Yanyan; King, Mark J; Zhong, Qiaoting
2018-03-21
Motor vehicle overloading is correlated with the possibility of road crash occurrence and severity. Although overloading of motor vehicles is pervasive in developing nations, few empirical analyses have been performed on factors that might influence the occurrence of overloading. This study aims to address this shortcoming by seeking evidence from several years of crash data from Guangdong province, China. Data on overloading and other factors are extracted for crash-involved vehicles from traffic crash records for 2006-2010 provided by the Traffic Management Bureau in Guangdong province. Logistic regression is applied to identify risk factors for overloading in crash-involved vehicles and within these crashes to identify factors contributing to greater crash severity. Driver, vehicle, road and environmental characteristics and violation types are considered in the regression models. In addition to the basic logistic models, association analysis is employed to identify the potential interactions among different risk factors during fitting the logistic models of overloading and severity. Crash-involved vehicles driven by males from rural households and in an unsafe condition are more likely to be overloaded and to be involved in higher severity overloaded vehicle crashes. If overloaded vehicles speed, the risk of severe traffic crash casualties increases. Young drivers (aged under 25 years) in mountainous areas are more likely to be involved in higher severity overloaded vehicle crashes. This study identifies several factors associated with overloading in crash-involved vehicles and with higher severity overloading crashes and provides an important reference for future research on those specific risk factors. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Weather impacts on single-vehicle truck crash injury severity.
Naik, Bhaven; Tung, Li-Wei; Zhao, Shanshan; Khattak, Aemal J
2016-09-01
The focus of this paper is on illustrating the feasibility of aggregating data from disparate sources to investigate the relationship between single-vehicle truck crash injury severity and detailed weather conditions. Specifically, this paper presents: (a) a methodology that combines detailed 15-min weather station data with crash and roadway data, and (b) an empirical investigation of the effects of weather on crash-related injury severities of single-vehicle truck crashes. Random parameters ordinal and multinomial regression models were used to investigate crash injury severity under different weather conditions, taking into account the individual unobserved heterogeneity. The adopted methodology allowed consideration of environmental, roadway, and climate-related variables in single-vehicle truck crash injury severity. Results showed that wind speed, rain, humidity, and air temperature were linked with single-vehicle truck crash injury severity. Greater recorded wind speed added to the severity of injuries in single-vehicle truck crashes in general. Rain and warmer air temperatures were linked to more severe crash injuries in single-vehicle truck crashes while higher levels of humidity were linked to less severe injuries. Random parameters ordered logit and multinomial logit, respectively, revealed some individual heterogeneity in the data and showed that integrating comprehensive weather data with crash data provided useful insights into factors associated with single-vehicle truck crash injury severity. The research provided a practical method that combined comprehensive 15-min weather station data with crash and roadway data, thereby providing useful insights into crash injury severity of single-vehicle trucks. Those insights are useful for future truck driver educational programs and for truck safety in different weather conditions. Copyright © 2016 Elsevier Ltd and National Safety Council. All rights reserved.
Investigations of Crashes Involving Pregnant Occupants
Klinich, Kathleen DeSantis; Schneider, Lawrence W.; Moore, Jamie L.; Pearlman, Mark D.
2000-01-01
Case reports of 16 crashes involving pregnant occupants are presented that illustrate the main conclusions of a crash-investigation program that includes 42 crashes investigated to date. Some unusual cases that are exceptions to the overall trends are also described. The study indicates a strong association between adverse fetal outcome and both crash severity and maternal injury. Proper restraint use, with and without airbag deployment, generally leads to acceptable fetal outcomes in lower severity crashes, while it does not affect fetal outcome in high-severity crashes. Compared to properly restrained pregnant occupants, improperly restrained occupants have a higher risk of adverse fetal outcome in lower severity crashes, which comprise the majority of all motor-vehicle collisions. PMID:11558095
Bulian, Christopher J [Yankton, SD; Dye, Robert C [Los Alamos, NM; Son, Steven F [Los Alamos, NM; Jorgensen, Betty S [Jemez Springs, NM; Perry, W Lee [Jemez Springs, NM
2009-09-22
Tungsten trioxide hydrate (WO.sub.3.H.sub.2O) was prepared from a precursor solution of ammonium paratungstate in concentrated aqueous hydrochloric acid. The precursor solution was rapidly added to water, resulting in the crash precipitation of a yellow white powder identified as WO.sub.3.H.sub.2O nanosized platelets by x-ray diffraction and scanning electron microscopy. Annealing of the powder at 200.degree. C. provided cubic phase WO.sub.3 nanopowder, and at 400.degree. C. provided WO.sub.3 nanopowder as a mixture of monoclinic and orthorhombic phases.
Numerical and behavioral effects within a pulse-driven system: consequences for shared prey.
Schmidt, Kenneth A; Ostfeld, Richard S
2008-03-01
Some of the clearest examples of the ramifying effects of resource pulses exist in deciduous forests dominated by mast-producing trees, such as oaks, beech, and hornbeam. Seed production in these forests represents only the first of several pulsed events. Secondary pulses emerge as mast-consuming small rodents numerically respond to seed production and tertiary pulses emerge as generalist predators numerically respond to rodents. Raptors may also respond behaviorally (i.e., diet shifts) to subsequent crashes in small rodents following the crash phase in seed production. In oak-dominated forest in the Hudson Valley, New York, these various pulse and crash phases act synergistically, although not simultaneously, to influence thrush population dynamics through predation on nests, juveniles, and adults. As a consequence, factors limiting population growth rate and their age-specific action vary as a function of past acorn production. We highlight these interactions based on our eight-year study of thrush demography, acorn production, and small mammal abundance coupled with information on regional adult thrush population trends from the Breeding Bird Survey. We use these data sets to demonstrate the sequence of primary to tertiary pulses and how they influence breeding thrush populations. To extend our discussion beyond masting phenomena in the eastern United States, we briefly review the literature of alternative avian prey within pulsed systems to show (1) numerical and behavioral responses by generalist predators are ubiquitous in pulsed systems, and this contributes to (2) variability in reproduction and survivorship of avian prey linked to the underlying dynamics of the pulse. We conclude by exploring the broad consequences of cascading resource pulses for alternative prey based upon the indirect interaction of apparent competition among shared prey and the nature of temporal variability on populations.
Statistical analysis of vehicle crashes in Mississippi based on crash data from 2010 to 2014.
DOT National Transportation Integrated Search
2017-08-15
Traffic crash data from 2010 to 2014 were collected by Mississippi Department of Transportation (MDOT) and extracted for the study. Three tasks were conducted in this study: (1) geographic distribution of crashes; (2) descriptive statistics of crash ...
DOT National Transportation Integrated Search
2010-06-01
The New Jersey Crash Record Geocoding Initiative was designed as a provisional measure to address missing crash locations. The purpose of the initiative was twofold. Primarily, students worked to locate crashes that had no location information after ...
Zaloshnja, Eduard; Miller, Ted; Council, Forrest; Persaud, Bhagwant
2004-01-01
This paper presents estimates for both the economic and comprehensive costs per crash for three police-coded severity groupings within 16 selected crash types and within two speed limit categories (
Vehicular crash data used to rank intersections by injury crash frequency and severity.
Liu, Yi; Li, Zongzhi; Liu, Jingxian; Patel, Harshingar
2016-09-01
This article contains data on research conducted in "A double standard model for allocating limited emergency medical service vehicle resources ensuring service reliability" (Liu et al., 2016) [1]. The crash counts were sorted out from comprehensive crash records of over one thousand major signalized intersections in the city of Chicago from 2004 to 2010. For each intersection, vehicular crashes were counted by crash severity levels, including fatal, injury Types A, B, and C for major, moderate, and minor injury levels, property damage only (PDO), and unknown. The crash data was further used to rank intersections by equivalent injury crash frequency. The top 200 intersections with the highest number of crash occurrences identified based on crash frequency- and severity-based scenarios are shared in this brief. The provided data would be a valuable source for research in urban traffic safety analysis and could also be utilized to examine the effectiveness of traffic safety improvement planning and programming, intersection design enhancement, incident and emergency management, and law enforcement strategies.
Zaloshnja, Eduard; Miller, Ted; Council, Forrest; Persaud, Bhagwant
2004-01-01
This paper presents estimates for both the economic and comprehensive costs per crash for three police-coded severity groupings within 16 selected crash types and within two speed limit categories (<=45 and >=50 mph). The economic costs are hard dollar costs. The comprehensive costs include economic costs and quality of life losses. We merged previously developed costs per victim keyed on the Abbreviated Injury Scale (AIS) into US crash data files that scored injuries in both the AIS and police-coded severity scales to produce per crash estimates. The most costly crashes were non-intersection fatal/disabling injury crashes on a road with a speed limit of 50 miles per hour or higher where multiple vehicles crashed head-on or a single vehicle struck a human (over 1.69 and $1.16 million per crash, respectively). The annual cost of police-reported run-off-road collisions, which include both rollovers and object impacts, represented 34% of total costs. PMID:15319129
Predicting reduced visibility related crashes on freeways using real-time traffic flow data.
Hassan, Hany M; Abdel-Aty, Mohamed A
2013-06-01
The main objective of this paper is to investigate whether real-time traffic flow data, collected from loop detectors and radar sensors on freeways, can be used to predict crashes occurring at reduced visibility conditions. In addition, it examines the difference between significant factors associated with reduced visibility related crashes to those factors correlated with crashes occurring at clear visibility conditions. Random Forests and matched case-control logistic regression models were estimated. The findings indicated that real-time traffic variables can be used to predict visibility related crashes on freeways. The results showed that about 69% of reduced visibility related crashes were correctly identified. The results also indicated that traffic flow variables leading to visibility related crashes are slightly different from those variables leading to clear visibility crashes. Using time slices 5-15 minutes before crashes might provide an opportunity for the appropriate traffic management centers for a proactive intervention to reduce crash risk in real-time. Copyright © 2013 Elsevier Ltd. All rights reserved.
Levine, Zachary S.; Floridi, Luciano
2017-01-01
We investigate the causal uncertainty surrounding the flash crash in the U.S. Treasury bond market on October 15, 2014, and the unresolved concern that no clear link has been identified between the start of the flash crash at 9:33 and the opening of the U.S. equity market at 9:30. We consider the contributory effect of mini flash crashes in equity markets, and find that the number of equity mini flash crashes in the three-minute window between market open and the Treasury Flash Crash was 2.6 times larger than the number experienced in any other three-minute window in the prior ten weekdays. We argue that (a) this statistically significant finding suggests that mini flash crashes in equity markets both predicted and contributed to the October 2014 U.S. Treasury Bond Flash Crash, and (b) mini-flash crashes are important phenomena with negative externalities that deserve much greater scholarly attention. PMID:29091931
Seacrist, Thomas; Douglas, Ethan C; Huang, Elaine; Megariotis, James; Prabahar, Abhiti; Kashem, Abyaad; Elzarka, Ayya; Haber, Leora; MacKinney, Taryn; Loeb, Helen
2018-02-28
Motor vehicle crashes are the leading cause of death among young drivers. Though previous research has focused on crash events, near crashes offer additional data to help identify driver errors that could potentially lead to crashes as well as evasive maneuvers used to avoid them. The Strategic Highway Research Program 2 (SHRP2) Naturalistic Driving Study (NDS) contains extensive data on real-world driving and offers a reliable methodology to quantify and study near crashes. This article presents findings on near crashes and how they compare to crash events among teen, young adult, and experienced adult drivers. A subset from the SHRP2 database consisting of 1,653 near crashes for teen (16-19 years, n = 550), young adult (20-24 years, n = 748), and experienced adult (35-54 years, n = 591) drivers was used. Onboard instrumentation including scene cameras, accelerometers, and Global Positioning System logged time series data at 10 Hz. Scene videos were reviewed for all events to classify near crashes based on 7 types: rear-end, road departure, intersection, head-on, side-swipe, pedestrian/cyclist, and animal. Near crash rates, incident type, secondary tasks, and evasive maneuvers were compared across age groups and between crashes and near crashes. For rear-end near crashes, vehicle dynamic variables including near crash severity, headway distance, time headway, and time to collision at the time of braking were compared across age groups. Crashes and near crashes were combined to compare the frequency of critical events across age. Teen drivers exhibited a significantly higher (P <.01) near crash rate than young adult and experienced adult drivers. The near crash rates were 81.6, 56.6, and 37.3 near crashes per million miles for teens, young adults, and experienced adults, respectively. Teens were also involved in significantly more rear-end (P <.01), road departure (P <.01), side-swipe (P <.01), and animal (P <.05) near crashes compared to young and experienced adults. Teens exhibited a significantly greater (P <.01) critical event rate of 102.2 critical events per million miles compared to 72.4 and 40.0 critical events per million miles for young adults and experienced adults, respectively; the critical event rate ratio was 2.6 and 1.8 for teens and young adults, respectively. To our knowledge, this is the first study to examine near crashes among teen, young adult, and experienced adult drivers using SHRP2 naturalistic data. Near crash and critical event rates significantly decreased with increasing age and driver experience. Overall, teens were more than twice as likely to be involved in critical events compared to experienced adults. These data can be used to develop more targeted driver training programs and help manufacturers design active safety systems based on the most common driving errors for vulnerable road users.
Kashani, Ali Tavakoli; Besharati, Mohammad Mehdi
2017-06-01
The aim of this study was to uncover patterns of pedestrian crashes. In the first stage, 34,178 pedestrian-involved crashes occurred in Iran during a four-year period were grouped into homogeneous clusters using a clustering analysis. Next, some in-cluster and inter-cluster crash patterns were analysed. The clustering analysis yielded six pedestrian crash groups. Car/van/pickup crashes on rural roads as well as heavy vehicle crashes were found to be less frequent but more likely to be fatal compared to other crash clusters. In addition, after controlling for crash frequency in each cluster, it was found that the fatality rate of each pedestrian age group as well as the fatal crash involvement rate of each driver age group varies across the six clusters. Results of present study has some policy implications including, promoting pedestrian safety training sessions for heavy vehicle drivers, imposing limitations over elderly heavy vehicle drivers, reinforcing penalties toward under 19 drivers and motorcyclists. In addition, road safety campaigns in rural areas may be promoted to inform people about the higher fatality rate of pedestrians on rural roads. The crash patterns uncovered in this study might also be useful for prioritizing future pedestrian safety research areas.
Under-reporting of road traffic crash data in Ghana.
Salifu, Mohammed; Ackaah, Williams
2012-01-01
Having reliable estimates of the shortfalls in road traffic crash data is an important prerequisite for setting more realistic targets for crash/casualty reduction programmes and for a better appreciation of the socio-economic significance of road traffic crashes. This study was carried out to establish realistic estimates of the overall shortfall (under-reporting) in the official crash statistics in Ghana over an eight-year period (1997-2004). Surveys were conducted at hospitals and among drivers to generate relevant alternative data which were then matched against records in police crash data files and the official database. Overall shortfalls came from two sources, namely, 'non-reporting' and 'under-recording'. The results show that the level of non-reporting varied significantly with the severity of the crash from about 57% for property damage crashes through 8% for serious injury crashes to 0% for fatal crashes. Crashes involving cyclists and motorcyclists were also substantially non-reported. Under-recording on the other hand declined significantly over the period from an average of 37% in 1997-1998 to 27% in 2003-2004. Thus, the official statistics of road traffic crashes in Ghana are subject to significant shortfalls that need to be accounted for. Correction factors have therefore been suggested for adjusting the official data.
Characteristics of the Injury Environment in Far-Side Crashes
Digges, K.; Gabler, H; Mohan, P.; Alonso, B.
2005-01-01
The population of occupants in far-side crashes that are documented in the US National database (NASS/CDS) was studied. The annual number of front seat occupants with serious or fatal injuries in far-side planar and rollover crashes was 17,194. The crash environment that produces serious and fatal injuries to belted front seat occupants in planar far-side crashes was investigated in detail. It was found that both the change in velocity and extent of damage were important factors that relate to crash severity. The median severity for crashes with serious or fatal injuries was a lateral delta-V of 28 kph and an extent of damage of CDC 3.6. Vehicle-to-vehicle impacts were simulated by finite element models to determine the intrusion characteristics associated with the median crash condition. These simulations indicated that the side damage caused by the IIHS barrier was representative of the damage in crashes that produce serious injuries in far-side crashes. Occupant simulations of the IIHS barrier crash at 28 kph showed that existing dummies lack biofidelity in upper body motion. The analysis suggested test conditions for studying far-side countermeasures and supported earlier studies that showed the need for an improved dummy to evaluate safety performance in the far-side crash environment. PMID:16179148
Singh, Jai
2013-01-01
The objective of this study was a thorough reconsideration, within the framework of Newtonian mechanics and work-energy relationships, of the empirically interpreted relationships employed within the CRASH3 damage analysis algorithm in regards to linearity between barrier equivalent velocity (BEV) or peak collision force magnitude and residual damage depth. The CRASH3 damage analysis algorithm was considered, first in terms of the cases of collisions that produced no residual damage, in order to properly explain the damage onset speed and crush resistance terms. Under the modeling constraints of the collision partners representing a closed system and the a priori assumption of linearity between BEV or peak collision force magnitude and residual damage depth, the equations for the sole realistic model were derived. Evaluation of the work-energy relationships for collisions at or below the elastic limit revealed that the BEV or peak collision force magnitude relationships are bifurcated based upon the residual damage depth. Rather than being additive terms from the linear curve fits employed in the CRASH3 damage analysis algorithm, the Campbell b 0 and CRASH3 AL terms represent the maximum values that can be ascribed to the BEV or peak collision force magnitude, respectively, for collisions that produce zero residual damage. Collisions resulting in the production of non-zero residual damage depth already account for the surpassing of the elastic limit during closure and therefore the secondary addition of the elastic limit terms represents a double accounting of the same. This evaluation shows that the current energy absorbed formulation utilized in the CRASH3 damage analysis algorithm extraneously includes terms associated with the A and G stiffness coefficients. This sole realistic model, however, is limited, secondary to reducing the coefficient of restitution to a constant value for all cases in which the residual damage depth is nonzero. Linearity between BEV or peak collision force magnitude and residual damage depth may be applicable for particular ranges of residual damage depth for any given region of any given vehicle. Within the modeling construct employed by the CRASH3 damage algorithm, the case of uniform and ubiquitous linearity cannot be supported. Considerations regarding the inclusion of internal work recovered and restitution for modeling the separation phase change in velocity magnitude should account for not only the effects present during the evaluation of a vehicle-to-vehicle collision of interest but also to the approach taken for modeling the force-deflection response for each collision partner.
Influence of pedestrian age and gender on spatial and temporal distribution of pedestrian crashes.
Toran Pour, Alireza; Moridpour, Sara; Tay, Richard; Rajabifard, Abbas
2018-01-02
Every year, about 1.24 million people are killed in traffic crashes worldwide and more than 22% of these deaths are pedestrians. Therefore, pedestrian safety has become a significant traffic safety issue worldwide. In order to develop effective and targeted safety programs, the location- and time-specific influences on vehicle-pedestrian crashes must be assessed. The main purpose of this research is to explore the influence of pedestrian age and gender on the temporal and spatial distribution of vehicle-pedestrian crashes to identify the hotspots and hot times. Data for all vehicle-pedestrian crashes on public roadways in the Melbourne metropolitan area from 2004 to 2013 are used in this research. Spatial autocorrelation is applied in examining the vehicle-pedestrian crashes in geographic information systems (GIS) to identify any dependency between time and location of these crashes. Spider plots and kernel density estimation (KDE) are then used to determine the temporal and spatial patterns of vehicle-pedestrian crashes for different age groups and genders. Temporal analysis shows that pedestrian age has a significant influence on the temporal distribution of vehicle-pedestrian crashes. Furthermore, men and women have different crash patterns. In addition, results of the spatial analysis shows that areas with high risk of vehicle-pedestrian crashes can vary during different times of the day for different age groups and genders. For example, for those between ages 18 and 65, most vehicle-pedestrian crashes occur in the central business district (CBD) during the day, but between 7:00 p.m. and 6:00 a.m., crashes among this age group occur mostly around hotels, clubs, and bars. This research reveals that temporal and spatial distributions of vehicle-pedestrian crashes vary for different pedestrian age groups and genders. Therefore, specific safety measures should be in place during high crash times at different locations for different age groups and genders to increase the effectiveness of the countermeasures in preventing and reducing vehicle-pedestrian crashes.
DOT National Transportation Integrated Search
2016-08-01
This research supports establishing an updated understanding of the pedestrian crash problem and defining a way to connect the crash problem with vehicle-to-pedestrian (V2P) communication crash avoidance technology. It describes 5 priority pre-crash ...
Naturalistic Assessment of Novice Teenage Crash Experience
Lee, Suzanne E.; Simons-Morton, Bruce G.; Klauer, Sheila E.; Ouimet, Marie Claude; Dingus, Thomas A.
2011-01-01
Background Crash risk is highest during the first months after licensure. Current knowledge about teenagers’ driving exposure and the factors increasing their crash risk is based on self-reported data and crash database analyses. While these research tools are useful, new developments in naturalistic technologies have allowed researchers to examine newly-licensed teenagers’ exposure and crash risk factors in greater detail. The Naturalistic Teenage Driving Study (NTDS) described in this paper is the first study to follow a group of newly-licensed teenagers continuously for 18 months after licensure. The goals of this paper are to compare the crash and near-crash experience of drivers in the NTDS to national trends, to describe the methods and lessons learned in the NTDS, and to provide initial data on driving exposure for these drivers. Methods A data acquisition system was installed in the vehicles of 42 newly-licensed teenage drivers 16 years of age during their first 18 months of independent driving. It consisted of cameras, sensors (accelerometers, GPS, yaw, front radar, lane position, and various sensors obtained via the vehicle network), and a computer with removable hard drive. Data on the driving of participating parents was also collected when they drove the instrumented vehicle. Findings The primary findings after 18 months included the following: (1) crash and near-crash rates among teenage participants were significantly higher during the first six months of the study than the final 12 months, mirroring the national trends; (2) crash and near-crash rates were significantly higher for teenage than adult (parent) participants, also reflecting national trends; (3) teenaged driving exposure averaged between 507-710 kilometers (315-441 miles) per month over the study period, but varied substantially between participants with standard errors representing 8-14 percent of the mean; and (4) crash and near-crash types were very similar for male and female teenage drivers.. Discussion The findings are the first comparing crash and near-crash rates among novice teenage drivers with those of adults using the same vehicle over the same period of time. The finding of highly elevated crash rates of novice teenagers during the first six months of licensure are consistent with and confirm the archival crash data showing high crash risk for novice teenagers. The NTDS convenience sample of teenage drivers was similar to the U.S. teenage driver population in terms of exposure and crash experience. The dataset is expected be a valuable resource for future in-depth analyses of crash risk, exposure to risky driving conditions, and comparisons of teenage and adult driving performance in various driving situations. PMID:21545880
76 FR 53660 - Federal Motor Vehicle Safety Standards; Seat Belt Assemblies
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-29
... further require integration of electrical signals from existing front and side crash sensor information... require additional crash sensors for rollover and rear-end crash events for vehicles without such sensors. Crash imminent sensors, or sensors that detect an impending crash, may also be needed. It is also...
49 CFR 238.403 - Crash energy management.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 4 2014-10-01 2014-10-01 false Crash energy management. 238.403 Section 238.403... Equipment § 238.403 Crash energy management. (a) Each power car and trailer car shall be designed with a crash energy management system to dissipate kinetic energy during a collision. The crash energy...
49 CFR 238.403 - Crash energy management.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 4 2013-10-01 2013-10-01 false Crash energy management. 238.403 Section 238.403... Equipment § 238.403 Crash energy management. (a) Each power car and trailer car shall be designed with a crash energy management system to dissipate kinetic energy during a collision. The crash energy...
49 CFR 238.403 - Crash energy management.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 4 2012-10-01 2012-10-01 false Crash energy management. 238.403 Section 238.403... Equipment § 238.403 Crash energy management. (a) Each power car and trailer car shall be designed with a crash energy management system to dissipate kinetic energy during a collision. The crash energy...
49 CFR 238.403 - Crash energy management.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 4 2011-10-01 2011-10-01 false Crash energy management. 238.403 Section 238.403... Equipment § 238.403 Crash energy management. (a) Each power car and trailer car shall be designed with a crash energy management system to dissipate kinetic energy during a collision. The crash energy...
Facilities and Methods Used in Full-scale Airplane Crash-fire Investigation
NASA Technical Reports Server (NTRS)
Black, Dugald O.
1952-01-01
The facilities and the techniques employed in the conduct of full scale airplane crash-fire studies currently being conducted at the NACA Lewis laboratory are discussed herein. This investigation is part of a comprehensive study of the airplane crash-fire problem. The crash configuration chosen, the general physical layout of the crash site, the test methods, the instrumentation, the data-recording systems, and the post-crash examination procedure are described
Comparative analysis of PA-31-350 Chieftain (N44LV) accident and NASA crash test data
NASA Technical Reports Server (NTRS)
Hayduk, R. J.
1979-01-01
A full scale, controlled crash test to simulate the crash of a Piper PA-31-350 Chieftain airplane is described. Comparisons were performed between the simulated crash and the actual crash in order to assess seat and floor behavior, and to estimate the acceleration levels experienced in the craft at the time of impact. Photographs, acceleration histories, and the tested airplane crash data is used to augment the accident information to better define the crash conditions. Measured impact parameters are presented along with flight path velocity and angle in relation to the impact surface.
Real World Crash Evaluation of Vehicle Stability Control (VSC) Technology
Bahouth, G.
2005-01-01
This study quantifies the effect of Vehicle Stability Control (VSC) in reducing crash involvement rates for a subset of vehicles in the US fleet. Crash rates for a variety of impact types before and after VSC technology was implemented are compared. Police-reported crashes from six available US state files from 1998–2002 were analyzed including 13,987 crash-involved study vehicles not equipped with the technology and 5,671 crashes of vehicles equipped with VSC as a standard feature. Overall, an 11.2% (95% CI: 2.4%, 21.1%) reduction in multi-vehicle frontal crash involvement was identified for VSC-equipped vehicles. A 52.6% (95% CI: 42.5%, 62.7%) reduction in single-vehicle crash rates was found. PMID:16179137
Real world crash evaluation of vehicle stability control (VSC) technology.
Bahouth, G
2005-01-01
This study quantifies the effect of Vehicle Stability Control (VSC) in reducing crash involvement rates for a subset of vehicles in the US fleet. Crash rates for a variety of impact types before and after VSC technology was implemented are compared. Police-reported crashes from six available US state files from 1998-2002 were analyzed including 13,987 crash-involved study vehicles not equipped with the technology and 5,671 crashes of vehicles equipped with VSC as a standard feature. Overall, an 11.2% (95% CI: 2.4%, 21.1%) reduction in multi-vehicle frontal crash involvement was identified for VSC-equipped vehicles. A 52.6% (95% CI: 42.5%, 62.7%) reduction in single-vehicle crash rates was found.
Farmer, C M
2001-05-01
Fatal crash rates for passenger cars and vans were compared for the last model year before four-wheel antilock brakes were introduced and the first model year for which antilock brakes were standard equipment. A prior study, based on fatal crash experience through 1995, reported that vehicle models with antilock brakes were more likely than identical but 1-year-earlier models to be involved in crashes fatal to their own occupants, but were less likely to be involved in crashes fatal to occupants of other vehicles. Overall, there was no significant effect of antilocks on the likelihood of fatal crashes. Similar analyses, based on fatal crash experience during 1996-98, yielded very different results. During 1996-98, vehicles with antilock brakes were again less likely than earlier models to be involved in crashes fatal to occupants of other vehicles, but they were no longer overinvolved in crashes fatal to their own occupants.
Neighborhood Influences on Vehicle-Pedestrian Crash Severity.
Toran Pour, Alireza; Moridpour, Sara; Tay, Richard; Rajabifard, Abbas
2017-12-01
Socioeconomic factors are known to be contributing factors for vehicle-pedestrian crashes. Although several studies have examined the socioeconomic factors related to the location of the crashes, limited studies have considered the socioeconomic factors of the neighborhood where the road users live in vehicle-pedestrian crash modelling. This research aims to identify the socioeconomic factors related to both the neighborhoods where the road users live and where crashes occur that have an influence on vehicle-pedestrian crash severity. Data on vehicle-pedestrian crashes that occurred at mid-blocks in Melbourne, Australia, was analyzed. Neighborhood factors associated with road users' residents and location of crash were investigated using boosted regression tree (BRT). Furthermore, partial dependence plots were applied to illustrate the interactions between these factors. We found that socioeconomic factors accounted for 60% of the 20 top contributing factors to vehicle-pedestrian crashes. This research reveals that socioeconomic factors of the neighborhoods where the road users live and where the crashes occur are important in determining the severity of the crashes, with the former having a greater influence. Hence, road safety countermeasures, especially those focussing on the road users, should be targeted at these high-risk neighborhoods.
NASA Astrophysics Data System (ADS)
Gill, G.; Sakrani, T.; Cheng, W.; Zhou, J.
2017-09-01
Traffic safety is a major concern in the transportation industry due to immense monetary and emotional burden caused by crashes of various severity levels, especially the injury and fatality ones. To reduce such crashes on all public roads, the safety management processes are commonly implemented which include network screening, problem diagnosis, countermeasure identification, and project prioritization. The selection of countermeasures for potential mitigation of crashes is governed by the influential factors which impact roadway crashes. Crash prediction model is the tool widely adopted by safety practitioners or researchers to link various influential factors to crash occurrences. Many different approaches have been used in the past studies to develop better fitting models which also exhibit prediction accuracy. In this study, a crash prediction model is developed to investigate the vehicular crashes occurring at roadway segments. The spatial and temporal nature of crash data is exploited to form a spatiotemporal model which accounts for the different types of heterogeneities among crash data and geometric or traffic flow variables. This study utilizes the Poisson lognormal model with random effects, which can accommodate the yearly variations in explanatory variables and the spatial correlations among segments. The dependency of different factors linked with roadway geometric, traffic flow, and road surface type on vehicular crashes occurring at segments was established as the width of lanes, posted speed limit, nature of pavement, and AADT were found to be correlated with vehicle crashes.
Figler, Bradley D; Mack, Christopher D; Kaufman, Robert; Wessells, Hunter; Bulger, Eileen; Smith, Thomas G; Voelzke, Bryan
2014-03-01
The National Highway Traffic Safety Administration's New Car Assessment Program (NCAP) implemented side-impact crash testing on all new vehicles since 1998 to assess the likelihood of major thoracoabdominal injuries during a side-impact crash. Higher crash test rating is intended to indicate a safer car, but the real-world applicability of these ratings is unknown. Our objective was to determine the relationship between a vehicle's NCAP side-impact crash test rating and the risk of major thoracoabdominal injury among the vehicle's occupants in real-world side-impact motor vehicle crashes. The National Automotive Sampling System Crashworthiness Data System contains detailed crash and injury data in a sample of major crashes in the United States. For model years 1998 to 2010 and crash years 1999 to 2010, 68,124 occupants were identified in the Crashworthiness Data System database. Because 47% of cases were missing crash severity (ΔV), multiple imputation was used to estimate the missing values. The primary predictor of interest was the occupant vehicle's NCAP side-impact crash test rating, and the outcome of interest was the presence of major (Abbreviated Injury Scale [AIS] score ≥ 3) thoracoabdominal injury. In multivariate analysis, increasing NCAP crash test rating was associated with lower likelihood of major thoracoabdominal injury at high (odds ratio [OR], 0.8; 95% confidence interval [CI], 0.7-0.9; p < 0.01) and medium (OR, 0.9; 95% CI, 0.8-1.0; p < 0.05) crash severity (ΔV), but not at low ΔV (OR, 0.95; 95% CI, 0.8-1.2; p = 0.55). In our model, older age and absence of seat belt use were associated with greater likelihood of major thoracoabdominal injury at low and medium ΔV (p < 0.001), but not at high ΔV (p ≥ 0.09). Among adults in model year 1998 to 2010 vehicles involved in medium and high severity motor vehicle crashes, a higher NCAP side-impact crash test rating is associated with a lower likelihood of major thoracoabdominal trauma. Epidemiologic study, level III.
Identifying crash-prone traffic conditions under different weather on freeways.
Xu, Chengcheng; Wang, Wei; Liu, Pan
2013-09-01
Understanding the relationships between traffic flow characteristics and crash risk under adverse weather conditions will help highway agencies develop proactive safety management strategies to improve traffic safety in adverse weather conditions. The primary objective is to develop separate crash risk prediction models for different weather conditions. The crash data, weather data, and traffic data used in this study were collected on the I-880N freeway in California in 2008 and 2010. This study considered three different weather conditions: clear weather, rainy weather, and reduced visibility weather. The preliminary analysis showed that there was some heterogeneity in the risk estimates for traffic flow characteristics by weather conditions, and that the crash risk prediction model for all weather conditions cannot capture the impacts of the traffic flow variables on crash risk under adverse weather conditions. The Bayesian random intercept logistic regression models were applied to link the likelihood of crash occurrence with various traffic flow characteristics under different weather conditions. The crash risk prediction models were compared to their corresponding logistic regression model. It was found that the random intercept model improved the goodness-of-fit of the crash risk prediction models. The model estimation results showed that the traffic flow characteristics contributing to crash risk were different across different weather conditions. The speed difference between upstream and downstream stations was found to be significant in each crash risk prediction model. Speed difference between upstream and downstream stations had the largest impact on crash risk in reduced visibility weather, followed by that in rainy weather. The ROC curves were further developed to evaluate the predictive performance of the crash risk prediction models under different weather conditions. The predictive performance of the crash risk model for clear weather was better than those of the crash risk models for adverse weather conditions. The research results could promote a better understanding of the impacts of traffic flow characteristics on crash risk under adverse weather conditions, which will help transportation professionals to develop better crash prevention strategies in adverse weather. Copyright © 2013 National Safety Council and Elsevier Ltd. All rights reserved.
Conner, Kristen A; Smith, Gary A
2017-05-19
Nationally, motor vehicle crashes are the leading cause of death among youth ages 16 to 20 years. Graduated driver licensing (GDL) laws have been implemented to reduce motor vehicle crashes among teen drivers. Studies have shown decreases in teen crash rates and crash-related fatality rates following enactment of GDL laws. However, GDL laws typically apply to teens only until their 18th birthday; therefore, the effect, if any, that GDL laws have on youth drivers ages 18 to 20 years and whether these programs should be extended to include these older youth warrant further study. The objective of this study was to evaluate the effects of Ohio's 2007 revised GDL law on motor vehicle crashes and crash-related injuries for crashes involving teen drivers ages 16 to 20 years, with a focus on the effects on crashes involving drivers ages 18 to 20 years. Cross-sectional analysis of motor vehicle crashes involving drivers ages 16 to 20 years in Ohio in the pre-GDL (2004-2006) and post-GDL (2008-2010) periods was performed. Descriptive statistics and population-based crash rates for drivers and occupants ages 16 to 20 years were calculated, as well as rate ratios and 95% confidence intervals (CIs) comparing crashes in the pre-GDL and post-GDL periods. Compared with the pre-GDL period, the post-GDL period was associated with lower crash rates for drivers age 16 years (relative risk [RR] = 0.94; 95% CI, 0.90-0.98), age 17 years (RR = 0.90; 95% CI, 0.88-0.93), age 18 years (RR = 0.95; 95% CI, 0.92-0.97), and ages 16-17 years combined (RR = 0.92; 95% CI, 0.90-0.95). Crash rate was higher for the post-GDL period for drivers age 19 years (RR = 1.04; 95% CI, 1.01-1.07), age 20 years (RR = 1.09; 95% CI, 1.05-1.13), and ages 18-20 years combined (RR = 1.02; 95% CI, 1.00-1.03). Unlike previous studies, this investigation used linked data to evaluate the outcomes of all occupants in crashes involving drivers ages 16-20 years. The post-GDL period was associated with lower crash, injury crash, and fatal crash involvement among drivers and occupants ages 16-17 years but higher overall crash involvement for drivers and occupants ages 19 years, 20 years, and 18-20 years combined. These findings support extending GDL restrictions to novice drivers ages 18 through 20 years to reduce crashes in that group.
Cruz, Miguel A; Burger, Ronald; Keim, Mark
2007-01-01
On 11 September 2001, terrorists hijacked two passenger planes and crashed them into the two towers of the World Trade Center (WTC) in New York City. These synchronized attacks were the largest act of terrorism ever committed on US soil. The impacts, fires, and subsequent collapse of the towers killed and injured thousands of people. Within minutes after the first plane crashed into the WTC, the Centers for Disease Control and Prevention (CDC) in Atlanta, Georgia, initiated one of the largest public health responses in its history. Staff of the CDC provided technical assistance on several key public health issues. During the acute phase of the event, CDC personnel assisted with: (1) assessing hospital capacity; (2) establishing injury and disease surveillance activities; (3) deploying emergency coordinators/liaisons to facilitate inter-agency coordination with the affected jurisdictions; and (4) arranging rapid delivery of emergency medical supplies, therapeutics, and personal protective equipment. This incident highlighted the need for adequate planning for all potential hazards and the importance of interagency and interdepartmental coordination in preparing for and responding to public health emergencies.
Research safety vehicle, Phase II. Volume I. Executive summary. Final report jul 75-dec 76
DOE Office of Scientific and Technical Information (OSTI.GOV)
Struble, D.
1976-12-01
Volume I summarizes the results of the Minicars Research Safety Vehicle Phase II program, as detailed in Volumes II and III. Phase I identified trends leading to the desired national social goals of the mid-1980's in vehicle crashworthiness, crash avoidance, damageability, pedestrian safety, fuel economy, emissions and cost, and characterized an RSV to satisfy them. In Phase II an RSV prototype was designed, developed and tested to demonstrate the feasibility of meeting these goals simultaneously. Although further refinement is necessary to assure operational validity, in all categories the results meet or exceed the most advanced performance specified by The Presidentialmore » Task Force on Motor Vehicle Goals beyond 1980.« less
Severe injury in multiple impacts: Analysis of 1997-2015 NASS-CDS.
Viano, David C; Parenteau, Chantal S
2018-07-04
This is a descriptive study of the incidence and risk for severe injury in single-impact and multi-impact crashes by belt use and crash type using NASS-CDS. 1997-2015 NASS-CDS data were used to determine the distribution of crashes by the number of impacts and severe injury (Maximum Abbreviated Injury Score [MAIS] 4+F) to >15-year-old nonejected drivers by seat belt use in 1997+ MY vehicles. It compares the risk for severe injury in a single impact and in crashes involving 2, 3, or 4+ impacts in the collision with a focus on a frontal crash followed by other impacts. Most vehicle crashes involve a single impact (75.4% of 44,889,518 vehicles), followed by 2-impact crashes (19.6%), 3-impact crashes (5.0%) and 4+ impacts (2.6%). For lap-shoulder-belted drivers, the distribution of severe injury was 42.1% in a single impact, 29.3% in 2 impacts, 13.4% in 3 impacts, and 15.1% in 4+ impact crashes. The risk for a belted driver was 0.256 ± 0.031% in a single impact, 0.564 ± 0.079% in 2 impacts, 0.880 ± 0.125% in 3 impacts, and 2.121 ± 0.646% in 4+ impact. The increase in risk from a single crash to multi-impact collisions was statistically significant (P < .001). In a single impact, 53.8% of belted drivers were in a frontal crashes, 22.4% in side crashes, 20% in rear crashes, and 1.7% in rollover crashes. The risk for severe injury was highest in a rollover at 0.677 ± 0.250%, followed by near-side impact at 0.467 ± 0.084% and far-side impact at 0.237 ± 0.071%. Seat belt use was 82.4% effective in preventing severe injury (MAIS 4+F) in a rollover, 47.9% in a near-side impact, and 74.8% in a far-side impact. In 2-impact crashes with a belted driver, the most common sequence was a rear impact followed by a frontal crash at 1,843,506 (21.5%) with a risk for severe injury of 0.100 ± 0.058%. The second most common was a frontal impact followed by another frontal crash at 1,257,264 (14.7%) with a risk of 0.401 ± 0.057%. The risk was 0.658 ± 0.271% in a frontal impact followed by a rear impact. A near-side impact followed by a rear crash had the highest risk for severe injury at 2.073 ± 1.322%. Restraint systems are generally developed for a single crash or sled test. The risk for severe injury was significantly higher in 2-, 3-, and 4+-impact crashes than a single impact. The majority (57.9%) of severe injuries occurred in multi-impact crashes with belted drivers. The evaluation of restraint performance warrants additional study in multi-impact crashes.
Melvin, John W; Begeman, Paul C; Faller, Ronald K; Sicking, Dean L; McClellan, Scott B; Maynard, Edwin; Donegan, Michael W; Mallott, Annette M; Gideon, Thomas W
2006-11-01
Biomechanical analysis of Indy car crashes using on-board impact recorders (Melvin et al. 1998, Melvin et al. 2001) indicates that Indy car driver protection in high-energy crashes can be achieved in frontal, side, and rear crashes with severities in the range of 100 to 135 G peak deceleration and velocity changes in the range of 50 to 70 mph. These crashes were predominantly single-car impacts with the rigid concrete walls of oval tracks. This impressive level of protection was found to be due to the unique combination of a very supportive and tight-fitting cockpit-seating package, a six-point belt restraint system, and effective head padding with an extremely strong chassis that defines the seat and cockpit of a modern Indy car. In 2000 and 2001, a series of fatal crashes in stock car racing created great concern for improving the crash protection for drivers in those racecars. Unlike the Indy car, the typical racing stock car features a more spacious driver cockpit due to its resemblance to the shape of a passenger car. The typical racing seat used in stock cars did not have the same configuration or support characteristics of the Indy car seat, and five-point belt restraints were used. The tubular steel space frame chassis of a stock car also differs from an Indy car's composite chassis structure in both form and mechanical behavior. This paper describes the application of results of the biomechanical analysis of the Indy car crash studies to the unique requirements of stock car racing driver crash protection. Sled test and full-scale crash test data using both Hybrid III frontal crash anthropomorphic test devices (ATDs) and BioSID side crash ATDs for the purpose of evaluating countermeasures involving restraint systems, seats and head/neck restraints has been instrumental in guiding these developments. In addition, the development of deformable walls for oval tracks (the SAFER Barrier) is described as an adjunct to improved occupant restraint through control of the crash forces acting on a racing car. NASCAR (National Association for Stock Car Auto Racing, Inc) implemented crash recording in stock car racing in its three national series in 2002. Data from 2925 crashes from 2002 through the 2005 season are summarized in terms of crash severity, crash direction, injury outcome, and protective system performance.
Database improvements for motor vehicle/bicycle crash analysis
Lusk, Anne C; Asgarzadeh, Morteza; Farvid, Maryam S
2015-01-01
Background Bicycling is healthy but needs to be safer for more to bike. Police crash templates are designed for reporting crashes between motor vehicles, but not between vehicles/bicycles. If written/drawn bicycle-crash-scene details exist, these are not entered into spreadsheets. Objective To assess which bicycle-crash-scene data might be added to spreadsheets for analysis. Methods Police crash templates from 50 states were analysed. Reports for 3350 motor vehicle/bicycle crashes (2011) were obtained for the New York City area and 300 cases selected (with drawings and on roads with sharrows, bike lanes, cycle tracks and no bike provisions). Crashes were redrawn and new bicycle-crash-scene details were coded and entered into the existing spreadsheet. The association between severity of injuries and bicycle-crash-scene codes was evaluated using multiple logistic regression. Results Police templates only consistently include pedal-cyclist and helmet. Bicycle-crash-scene coded variables for templates could include: 4 bicycle environments, 18 vehicle impact-points (opened-doors and mirrors), 4 bicycle impact-points, motor vehicle/bicycle crash patterns, in/out of the bicycle environment and bike/relevant motor vehicle categories. A test of including these variables suggested that, with bicyclists who had minor injuries as the control group, bicyclists on roads with bike lanes riding outside the lane had lower likelihood of severe injuries (OR, 0.40, 95% CI 0.16 to 0.98) compared with bicyclists riding on roads without bicycle facilities. Conclusions Police templates should include additional bicycle-crash-scene codes for entry into spreadsheets. Crash analysis, including with big data, could then be conducted on bicycle environments, motor vehicle potential impact points/doors/mirrors, bicycle potential impact points, motor vehicle characteristics, location and injury. PMID:25835304
Liu, Jun; Khattak, Asad J; Richards, Stephen H; Nambisan, Shashi
2015-12-01
Crashes at highway-rail grade crossings can result in severe injuries and fatalities to vehicle occupants. Using a crash database from the Federal Railroad Administration (N=15,639 for 2004-2013), this study explores differences in safety outcomes from crashes between passive controls (Crossbucks and STOP signs) and active controls (flashing lights, gates, audible warnings and highway signals). To address missing data, an imputation model is developed, creating a complete dataset for estimation. Path analysis is used to quantify the direct and indirect associations of passive and active controls with pre-crash behaviors and crash outcomes in terms of injury severity. The framework untangles direct and indirect associations of controls by estimating two models, one for pre-crash driving behaviors (e.g., driving around active controls), and another model for injury severity. The results show that while the presence of gates is not directly associated with injury severity, the indirect effect through stopping behavior is statistically significant (95% confidence level) and substantial. Drivers are more likely to stop at gates that also have flashing lights and audible warnings, and stopping at gates is associated with lower injury severity. This indirect association lowers the chances of injury by 16%, compared with crashes at crossings without gates. Similar relationships between other controls and injury severity are explored. Generally, crashes occurring at active controls are less severe than crashes at passive controls. The results of study can be used to modify Crash Modification Factors (CMFs) to account for crash injury severity. The study contributes to enhancing the understanding of safety by incorporating pre-crash behaviors in a broader framework that quantifies correlates of crash injury severity at active and passive crossings. Copyright © 2015 Elsevier Ltd. All rights reserved.
Comparison of four statistical and machine learning methods for crash severity prediction.
Iranitalab, Amirfarrokh; Khattak, Aemal
2017-11-01
Crash severity prediction models enable different agencies to predict the severity of a reported crash with unknown severity or the severity of crashes that may be expected to occur sometime in the future. This paper had three main objectives: comparison of the performance of four statistical and machine learning methods including Multinomial Logit (MNL), Nearest Neighbor Classification (NNC), Support Vector Machines (SVM) and Random Forests (RF), in predicting traffic crash severity; developing a crash costs-based approach for comparison of crash severity prediction methods; and investigating the effects of data clustering methods comprising K-means Clustering (KC) and Latent Class Clustering (LCC), on the performance of crash severity prediction models. The 2012-2015 reported crash data from Nebraska, United States was obtained and two-vehicle crashes were extracted as the analysis data. The dataset was split into training/estimation (2012-2014) and validation (2015) subsets. The four prediction methods were trained/estimated using the training/estimation dataset and the correct prediction rates for each crash severity level, overall correct prediction rate and a proposed crash costs-based accuracy measure were obtained for the validation dataset. The correct prediction rates and the proposed approach showed NNC had the best prediction performance in overall and in more severe crashes. RF and SVM had the next two sufficient performances and MNL was the weakest method. Data clustering did not affect the prediction results of SVM, but KC improved the prediction performance of MNL, NNC and RF, while LCC caused improvement in MNL and RF but weakened the performance of NNC. Overall correct prediction rate had almost the exact opposite results compared to the proposed approach, showing that neglecting the crash costs can lead to misjudgment in choosing the right prediction method. Copyright © 2017 Elsevier Ltd. All rights reserved.
Harland, Karisa K; Carney, Cher; McGehee, Daniel
2016-07-03
The objective of this study was to estimate the prevalence and odds of fleet driver errors and potentially distracting behaviors just prior to rear-end versus angle crashes. Analysis of naturalistic driving videos among fleet services drivers for errors and potentially distracting behaviors occurring in the 6 s before crash impact. Categorical variables were examined using the Pearson's chi-square test, and continuous variables, such as eyes-off-road time, were compared using the Student's t-test. Multivariable logistic regression was used to estimate the odds of a driver error or potentially distracting behavior being present in the seconds before rear-end versus angle crashes. Of the 229 crashes analyzed, 101 (44%) were rear-end and 128 (56%) were angle crashes. Driver age, gender, and presence of passengers did not differ significantly by crash type. Over 95% of rear-end crashes involved inadequate surveillance compared to only 52% of angle crashes (P < .0001). Almost 65% of rear-end crashes involved a potentially distracting driver behavior, whereas less than 40% of angle crashes involved these behaviors (P < .01). On average, drivers spent 4.4 s with their eyes off the road while operating or manipulating their cell phone. Drivers in rear-end crashes were at 3.06 (95% confidence interval [CI], 1.73-5.44) times adjusted higher odds of being potentially distracted than those in angle crashes. Fleet driver driving errors and potentially distracting behaviors are frequent. This analysis provides data to inform safe driving interventions for fleet services drivers. Further research is needed in effective interventions to reduce the likelihood of drivers' distracting behaviors and errors that may potentially reducing crashes.
Prevalence of teen driver errors leading to serious motor vehicle crashes.
Curry, Allison E; Hafetz, Jessica; Kallan, Michael J; Winston, Flaura K; Durbin, Dennis R
2011-07-01
Motor vehicle crashes are the leading cause of adolescent deaths. Programs and policies should target the most common and modifiable reasons for crashes. We estimated the frequency of critical reasons for crashes involving teen drivers, and examined in more depth specific teen driver errors. The National Highway Traffic Safety Administration's (NHTSA) National Motor Vehicle Crash Causation Survey collected data at the scene of a nationally representative sample of 5470 serious crashes between 7/05 and 12/07. NHTSA researchers assigned a single driver, vehicle, or environmental factor as the critical reason for the event immediately leading to each crash. We analyzed crashes involving 15-18 year old drivers. 822 teen drivers were involved in 795 serious crashes, representing 335,667 teens in 325,291 crashes. Driver error was by far the most common reason for crashes (95.6%), as opposed to vehicle or environmental factors. Among crashes with a driver error, a teen made the error 79.3% of the time (75.8% of all teen-involved crashes). Recognition errors (e.g., inadequate surveillance, distraction) accounted for 46.3% of all teen errors, followed by decision errors (e.g., following too closely, too fast for conditions) (40.1%) and performance errors (e.g., loss of control) (8.0%). Inadequate surveillance, driving too fast for conditions, and distracted driving together accounted for almost half of all crashes. Aggressive driving behavior, drowsy driving, and physical impairments were less commonly cited as critical reasons. Males and females had similar proportions of broadly classified errors, although females were specifically more likely to make inadequate surveillance errors. Our findings support prioritization of interventions targeting driver distraction and surveillance and hazard awareness training. Copyright © 2010 Elsevier Ltd. All rights reserved.
Assessing the role of pavement macrotexture in preventing crashes on highways.
Pulugurtha, Srinivas S; Kusam, Prasanna R; Patel, Kuvleshay J
2010-02-01
The objective of this article is to assess the role of pavement macrotexture in preventing crashes on highways in the State of North Carolina. Laser profilometer data obtained from the North Carolina Department of Transportation (NCDOT) for highways comprising four corridors are processed to calculate pavement macrotexture at 100-m (approximately 330-ft) sections according to the American Society for Testing and Materials (ASTM) standards. Crash data collected over the same lengths of the corridors were integrated with the calculated pavement macrotexture for each section. Scatterplots were generated to assess the role of pavement macrotexture on crashes and logarithm of crashes. Regression analyses were conducted by considering predictor variables such as million vehicle miles of travel (as a function of traffic volume and length), the number of interchanges, the number of at-grade intersections, the number of grade-separated interchanges, and the number of bridges, culverts, and overhead signs along with pavement macrotexture to study the statistical significance of relationship between pavement macrotexture and crashes (both linear and log-linear) when compared to other predictor variables. Scatterplots and regression analysis conducted indicate a more statistically significant relationship between pavement macrotexture and logarithm of crashes than between pavement macrotexture and crashes. The coefficient for pavement macrotexture, in general, is negative, indicating that the number of crashes or logarithm of crashes decreases as it increases. The relation between pavement macrotexture and logarithm of crashes is generally stronger than between most other predictor variables and crashes or logarithm of crashes. Based on results obtained, it can be concluded that maintaining pavement macrotexture greater than or equal to 1.524 mm (0.06 in.) as a threshold limit would possibly reduce crashes and provide safe transportation to road users on highways.
Spinal injury in car crashes: crash factors and the effects of occupant age.
Bilston, Lynne E; Clarke, Elizabeth C; Brown, Julie
2011-08-01
Motor vehicle crashes are the leading cause of serious spinal injury in most developed nations. However, since these injuries are rare, systematic analyses of the crash factors that are predictive of spinal injury have rarely been performed. This study aimed to use a population-reference crash sample to identify crash factors associated with moderate to severe spinal injury, and how these vary with occupant age. The US National Automotive Sampling System Crashworthiness Data System (NASS) data for 1993-2007 were analysed using logistic regression to identify crash factors associated with Abbreviated Injury Scale (AIS)2+ spinal injury among restrained vehicle passengers. Risk of moderate or severe spinal injury (AIS2+) was associated with higher severity crashes (OR=3.5 (95% CI 2.6 to 4.6)), intrusion into an occupant's seating position (OR=2.7 (95% CI 1.9 to 3.7)), striking a fixed object rather than another car (OR=1.7 (95% CI 1.3 to 2.1)), and use of a shoulder-only belt (OR=2.7 (95% CI 1.5 to 4.8)). Older occupants (65 years or older) were at higher risk of spinal injury than younger adults in frontal, side and rollover crashes. Children under 16 were at a lower risk of spinal injury than adults in all crash types except frontal crashes. While the risk of serious spinal injury in motor vehicle crashes is low, these injuries are more common in crashes of higher severity or into fixed objects, and in the presence of intrusion. There are elevated risks of spinal injury for older occupants compared with younger adults, which may reflect changes in biomechanical tolerances with age. Children appear to be at lower risk of serious spinal injury than adults except in frontal crashes.
Fitzpatrick, Cole D; Rakasi, Saritha; Knodler, Michael A
2017-01-01
Speed is one of the most important factors in traffic safety as higher speeds are linked to increased crash risk and higher injury severities. Nearly a third of fatal crashes in the United States are designated as "speeding-related", which is defined as either "the driver behavior of exceeding the posted speed limit or driving too fast for conditions." While many studies have utilized the speeding-related designation in safety analyses, no studies have examined the underlying accuracy of this designation. Herein, we investigate the speeding-related crash designation through the development of a series of logistic regression models that were derived from the established speeding-related crash typologies and validated using a blind review, by multiple researchers, of 604 crash narratives. The developed logistic regression model accurately identified crashes which were not originally designated as speeding-related but had crash narratives that suggested speeding as a causative factor. Only 53.4% of crashes designated as speeding-related contained narratives which described speeding as a causative factor. Further investigation of these crashes revealed that the driver contributing code (DCC) of "driving too fast for conditions" was being used in three separate situations. Additionally, this DCC was also incorrectly used when "exceeding the posted speed limit" would likely have been a more appropriate designation. Finally, it was determined that the responding officer only utilized one DCC in 82% of crashes not designated as speeding-related but contained a narrative indicating speed as a contributing causal factor. The use of logistic regression models based upon speeding-related crash typologies offers a promising method by which all possible speeding-related crashes could be identified. Published by Elsevier Ltd.
Abdel-Aty, Mohamed; Chundi, Sai Srinivas; Lee, Chris
2007-01-01
There is a growing concern with the safety of school-aged children. This study identifies the locations of pedestrian/bicyclist crashes involving school-aged children and examines the conditions when these crashes are more likely to occur. The 5-year records of crashes in Orange County, Florida where school-aged children were involved were used. The spatial distribution of these crashes was investigated using the Geographic Information Systems (GIS) and the likelihoods of crash occurrence under different conditions were estimated using log-linear models. A majority of school-aged children crashes occurred in the areas near schools. Although elementary school children were generally very involved, middle and high school children were more involved in crashes, particularly on high-speed multi-lane roadways. Driver's age, gender, and alcohol use, pedestrian's/bicyclist's age, number of lanes, median type, speed limits, and speed ratio were also found to be correlated with the frequency of crashes. The result confirms that school-aged children are exposed to high crash risk near schools. High crash involvement of middle and high school children reflects that middle and high schools tend to be located near multi-lane high-speed roads. The pedestrian's/bicyclist's demographic factors and geometric characteristics of the roads adjacent to schools associated with school children's crash involvement are of interest to school districts.
Helicopter crashes related to oil and gas operations in the Gulf of Mexico.
Baker, Susan P; Shanahan, Dennis F; Haaland, Wren; Brady, Joanne E; Li, Guohua
2011-09-01
The hazards inherent in flight operations in the Gulf of Mexico prompted investigation of the number and circumstances of crashes related to oil and gas operations in the region. The National Transportation Safety Board (NTSB) database was queried for helicopter crashes during 1983 through 2009 related to Gulf of Mexico oil or gas production. The crashes were identified based on word searches confirmed by a narrative statement indicating that the flight was related to oil or gas operations. During 1983-2009, the NTSB recorded a total of 178 helicopter crashes related to oil and gas operations in the Gulf of Mexico, with an average of 6.6 crashes per year (5.6 annually during 1983-1999 vs. 8.2 during 2000-2009). The crashes resulted in a total of 139 fatalities, including 41 pilots. Mechanical failure was the most common precipitating factor, accounting for 68 crashes (38%). Bad weather led to 29 crashes (16%), in which 40% of the 139 deaths occurred. Pilot error was cited by the NTSB in 83 crashes (47%). After crashes or emergency landings on water, 15 helicopters sank when flotation devices were not activated automatically or by pilots. Mechanical failure, non-activation of flotation, and pilot error are major problems to be addressed if crashes and deaths in this lethal environment are to be reduced.
DOT National Transportation Integrated Search
1998-10-01
The report uses police-reported crash data that have been linked to hospital discharge data to evaluate charges for hospital care provided to motor vehicle crash victims in Pennsylvania. Approximately 17,000 crash victims were hospitalized in Pennsyl...
Injury severity data for front and second row passengers in frontal crashes.
Atkinson, Theresa; Leszek Gawarecki; Tavakoli, Massoud
2016-06-01
The data contained here were obtained from the National Highway Transportation Safety Administration׳s National Automotive Sampling System - Crashworthiness Data System (NASS-CDS) for the years 2008-2014. This publically available data set monitors motor vehicle crashes in the United States, using a stratified random sample frame, resulting in information on approximately 5000 crashes each year that can be utilized to create national estimates for crashes. The NASS-CDS data sets document vehicle, crash, and occupant factors. These data can be utilized to examine public health, law enforcement, roadway planning, and vehicle design issues. The data provided in this brief are a subset of crash events and occupants. The crashes provided are exclusively frontal crashes. Within these crashes, only restrained occupants who were seated in the right front seat position or the second row outboard seat positions were included. The front row and second row data sets were utilized to construct occupant pairs crashes where both a right front seat occupant and a second row occupant were available. Both unpaired and paired data sets are provided in this brief.
Injury severity data for front and second row passengers in frontal crashes
Atkinson, Theresa; Leszek Gawarecki; Tavakoli, Massoud
2016-01-01
The data contained here were obtained from the National Highway Transportation Safety Administration׳s National Automotive Sampling System – Crashworthiness Data System (NASS-CDS) for the years 2008–2014. This publically available data set monitors motor vehicle crashes in the United States, using a stratified random sample frame, resulting in information on approximately 5000 crashes each year that can be utilized to create national estimates for crashes. The NASS-CDS data sets document vehicle, crash, and occupant factors. These data can be utilized to examine public health, law enforcement, roadway planning, and vehicle design issues. The data provided in this brief are a subset of crash events and occupants. The crashes provided are exclusively frontal crashes. Within these crashes, only restrained occupants who were seated in the right front seat position or the second row outboard seat positions were included. The front row and second row data sets were utilized to construct occupant pairs crashes where both a right front seat occupant and a second row occupant were available. Both unpaired and paired data sets are provided in this brief. PMID:27077084
Perception-based road hazard identification with Internet support.
Tarko, Andrew P; DeSalle, Brian R
2003-01-01
One of the most important tasks faced by highway agencies is identifying road hazards. Agencies use crash statistics to detect road intersections and segments where the frequency of crashes is excessive. With the crash-based method, a dangerous intersection or segment can be pointed out only after a sufficient number of crashes occur. A more proactive method is needed, and motorist complaints may be able to assist agencies in detecting road hazards before crashes occur. This paper investigates the quality of safety information reported by motorists and the effectiveness of hazard identification based on motorist reports, which were collected with an experimental Internet website. It demonstrates that the intersections pointed out by motorists tended to have more crashes than other intersections. The safety information collected through the website was comparable to 2-3 months of crash data. It was concluded that although the Internet-based method could not substitute for the traditional crash-based methods, its joint use with crash statistics might be useful in detecting new hazards where crash data had been collected for a short time.
Tay, Richard; Rifaat, Shakil Mohammad; Chin, Hoong Chor
2008-07-01
Leaving the scene of a crash without reporting it is an offence in most countries and many studies have been devoted to improving ways to identify hit-and-run vehicles and the drivers involved. However, relatively few studies have been conducted on identifying factors that contribute to the decision to run after the crash. This study identifies the factors that are associated with the likelihood of hit-and-run crashes including driver characteristics, vehicle types, crash characteristics, roadway features and environmental characteristics. Using a logistic regression model to delineate hit-and-run crashes from nonhit-and-run crashes, this study found that drivers were more likely to run when crashes occurred at night, on a bridge and flyover, bend, straight road and near shop houses; involved two vehicles, two-wheel vehicles and vehicles from neighboring countries; and when the driver was a male, minority, and aged between 45 and 69. On the other hand, collisions involving right turn and U-turn maneuvers, and occurring on undivided roads were less likely to be hit-and-run crashes.
Bahouth, George; Digges, Kennerly; Schulman, Carl
2012-01-01
This paper presents methods to estimate crash injury risk based on crash characteristics captured by some passenger vehicles equipped with Advanced Automatic Crash Notification technology. The resulting injury risk estimates could be used within an algorithm to optimize rescue care. Regression analysis was applied to the National Automotive Sampling System / Crashworthiness Data System (NASS/CDS) to determine how variations in a specific injury risk threshold would influence the accuracy of predicting crashes with serious injuries. The recommended thresholds for classifying crashes with severe injuries are 0.10 for frontal crashes and 0.05 for side crashes. The regression analysis of NASS/CDS indicates that these thresholds will provide sensitivity above 0.67 while maintaining a positive predictive value in the range of 0.20. PMID:23169132
Spatial panel analyses of alcohol outlets and motor vehicle crashes in California: 1999–2008
Ponicki, William R.; Gruenewald, Paul J.; Remer, Lillian G.
2014-01-01
Although past research has linked alcohol outlet density to higher rates of drinking and many related social problems, there is conflicting evidence of density’s association with traffic crashes. An abundance of local alcohol outlets simultaneously encourages drinking and reduces driving distances required to obtain alcohol, leading to an indeterminate expected impact on alcohol-involved crash risk. This study separately investigates the effects of outlet density on (1) the risk of injury crashes relative to population and (2) the likelihood that any given crash is alcohol-involved, as indicated by police reports and single-vehicle nighttime status of crashes. Alcohol outlet density effects are estimated using Bayesian misalignment Poisson analyses of all California ZIP codes over the years 1999–2008. These misalignment models allow panel analysis of ZIP-code data despite frequent redefinition of postal-code boundaries, while also controlling for overdispersion and the effects of spatial autocorrelation. Because models control for overall retail density, estimated alcohol-outlet associations represent the extra effect of retail establishments selling alcohol. The results indicate a number of statistically well-supported associations between retail density and crash behavior, but the implied effects on crash risks are relatively small. Alcohol-serving restaurants have a greater impact on overall crash risks than on the likelihood that those crashes involve alcohol, whereas bars primarily affect the odds that crashes are alcohol-involved. Off-premise outlet density is negatively associated with risks of both crashes and alcohol involvement, while the presence of a tribal casino in a ZIP code is linked to higher odds of police-reported drinking involvement. Alcohol outlets in a given area are found to influence crash risks both locally and in adjacent ZIP codes, and significant spatial autocorrelation also suggests important relationships across geographical units. These results suggest that each type of alcohol outlet can have differing impacts on risks of crashing as well as the alcohol involvement of those crashes. PMID:23537623
A multiyear assessment of a hospital-school program to promote teen motor vehicle safety.
Unni, Purnima; Estrada, Cristina M; Chung, Dai H; Riley, Emily B; Worsley-Hynd, Lesley; Stinson, Neil
2017-08-01
Motor vehicle crashes are the leading cause of death among teen drivers. The main goal of this program was to reduce texting while driving among high school teens through a unique peer-generated anti-texting campaign. The program consisted of two phases. In phase 1, student leaders participated in a half-day, hospital-based experiential program that emphasized safe teen driving. In phase 2, these students conceptualized and implemented an anti-texting while driving campaign during the school year. The program enrolled 32 schools with 137 student participants in phase 1.This study uses a prospective quasi-experimental pre-post design. A presurvey and a follow-up online survey were used. Response rate was 81%. In phase 2, two rounds of observations of drivers were made near the participating schools at the beginning and end of the phase 2 campaign. The results were analyzed using proportion tests. There was a strong belief (6.49 on a seven-point scale) that texting while driving could result in a crash. About 58% had texted while driving in the previous 7 days in the pre-survey. This proportion decreased significantly to 44% in the follow-up (p < 0.05). Knowledge of Tennessee Graduated Driver Licensing laws and feeling of empowerment to take action with a teen driver who was texting improved significantly (p < 0.05). In phase 2, 12,309 drivers (adults and teens) were observed in the first round, and 13,153 were observed in the second round of observations. Significant reduction in the proportion of drivers texting while driving (from 13% to 9%; p < 0.0001) was observed. Results of driver observations support the effectiveness of this program in meeting the key objective of reducing texting while driving. The program also influenced teenagers' willingness to take positive steps when faced with a driver who was texting. Future efforts should aim to influence social and peer norms. Therapeutic study, level III.
A multiyear assessment of a hospital-school program to promote teen motor vehicle safety.
Unni, Purnima; Estrada, Cristina M; Chung, Dai H; Riley, Emily B; Worsley-Hynd, Lesley; Stinson, Neil
2017-11-01
Motor vehicle crashes are the leading cause of death among teen drivers. The main goal of this program was to reduce texting while driving among high school teens through a unique peer-generated anti-texting campaign. The program consisted of two phases. In phase 1, student leaders participated in a half-day, hospital-based experiential program that emphasized safe teen driving. In phase 2, these students conceptualized and implemented an anti-texting while driving campaign during the school year. The program enrolled 32 schools with 137 student participants in phase 1. This study uses a prospective quasi-experimental pre-post design. A presurvey and a follow-up online survey were used. Response rate was 81%. In phase 2, two rounds of observations of drivers were made near the participating schools at the beginning and end of the phase 2 campaign. The results were analyzed using proportion tests. There was a strong belief (6.49 on a seven-point scale) that texting while driving could result in a crash. About 58% had texted while driving in the previous 7 days in the pre-survey. This proportion decreased significantly to 44% in the follow-up (p < 0.05). Knowledge of Tennessee Graduated Driver Licensing laws and feeling of empowerment to take action with a teen driver who was texting improved significantly (p < 0.05). In phase 2, 12,309 drivers (adults and teens) were observed in the first round, and 13,153 were observed in the second round of observations. Significant reduction in the proportion of drivers texting while driving (from 13% to 9%; p < 0.0001) was observed. Results of driver observations support the effectiveness of this program in meeting the key objective of reducing texting while driving. The program also influenced teenagers' willingness to take positive steps when faced with a driver who was texting. Future efforts should aim to influence social and peer norms. Therapeutic study, level IV.
Incidence and crash mechanisms of aortic injury during the past decade.
Schulman, Carl I; Carvajal, Daniel; Lopez, Peter P; Soffer, Dror; Habib, Fahim; Augenstein, Jeffrey
2007-03-01
Aortic injuries were traditionally thought to be the result of severe frontal crashes. Newer data has suggested other crash types such as nearside crashes may also be important in aortic injury. We hypothesized the implementation of recent safety measures would decrease the incidence of aortic injury associated with fatal motor vehicle crashes. The autopsy reports of all traffic fatalities for motor vehicle occupants in a large urban county for the years 1993 to 2004 were examined. The demographics, impact types, safety measures used, and the presence of any aortic injury were recorded. Trends were evaluated for significance by weighted linear regression. The incidence of aortic injury associated with fatal motor vehicle crashes has remained unchanged during the past 12 years (r = 0.057, p = 0.45). There is a trend toward decreased aortic injuries associated with frontal crashes (r = 0.26, p = 0.089) but no change in aortic injuries associated with nearside or farside crashes (r = 0.053, p = 0.47), when the crash resulted in a fatality. This is despite an increase in seat belt use and increased presence of airbags during the same time period. Despite improved safety measures designed to minimize the occurrence of aortic injuries, the incidence of blunt aortic injury in fatal motor vehicle crashes has not decreased during the past decade. Although not statistically significant, there is a trend toward decreased frontal impacts in fatal motor vehicle crashes associated with aortic injuries. The nearside crash mechanism continues to play a prominent role, and efforts at improving vehicle safety should be focused on crash mechanisms as they relate to aortic injury.
Investigation of pedestrian crashes on two-way two-lane rural roads in Ethiopia.
Tulu, Getu Segni; Washington, Simon; Haque, Md Mazharul; King, Mark J
2015-05-01
Understanding pedestrian crash causes and contributing factors in developing countries is critically important as they account for about 55% of all traffic crashes. Not surprisingly, considerable attention in the literature has been paid to road traffic crash prediction models and methodologies in developing countries of late. Despite this interest, there are significant challenges confronting safety managers in developing countries. For example, in spite of the prominence of pedestrian crashes occurring on two-way two-lane rural roads, it has proven difficult to develop pedestrian crash prediction models due to a lack of both traffic and pedestrian exposure data. This general lack of available data has further hampered identification of pedestrian crash causes and subsequent estimation of pedestrian safety performance functions. The challenges are similar across developing nations, where little is known about the relationship between pedestrian crashes, traffic flow, and road environment variables on rural two-way roads, and where unique predictor variables may be needed to capture the unique crash risk circumstances. This paper describes pedestrian crash safety performance functions for two-way two-lane rural roads in Ethiopia as a function of traffic flow, pedestrian flows, and road geometry characteristics. In particular, random parameter negative binomial model was used to investigate pedestrian crashes. The models and their interpretations make important contributions to road crash analysis and prevention in developing countries. They also assist in the identification of the contributing factors to pedestrian crashes, with the intent to identify potential design and operational improvements. Copyright © 2015. Published by Elsevier Ltd.
Epidemiology of pedestrian–MVCs by road type in Cluj, Romania
Hamann, Cara; Peek-Asa, Corinne; Rus, Diana
2017-01-01
Objective Pedestrian–motor vehicle (PMV) crash rates in Romania are among the highest in all of Europe. The purpose of this study was to examine the characteristics of pedestrian–MVCs in Cluj County, Romania, on the two major types of roadways: national or local. Methods Cluj County police crash report data from 2010 were used to identify pedestrian, driver and crash characteristics of pedestrian–MVCs. Crashes with available location data were geocoded and road type (national or local) for each crash was determined. Distributions of crash characteristics were examined by road type and multivariable logistic regression models were built to determine predictors of crash road type. Results Crashes occurring on national roads involved more teenagers and adults, while those on local roads involved more young children (0–12) and older adults (65+) (p<0.01). Crashes on national roads were more likely to have marked pedestrian crossings and shoulders compared with local crashes. Pedestrian–MVCs that involved a moving violation by the motorist were more likely to occur on national roadways (adjusted OR=1.93, 95% CI 1.07 to 3.49). Conclusions Pedestrian–MVCs pose a considerable health burden in Romania. Results from this study suggest that factors leading to PMV crashes on national roads are more likely to involve driver-related causes compared with local roads. Intervention priorities to reduce pedestrian crashes on national roads should be directed towards driver behaviour on national roads. Further examination of driver and pedestrian behaviours related to crash risk on both national and local roads, such as distraction and speeding, is warranted. PMID:25178278
Costs of Crashes to Government, United States, 2008
Miller, Ted R; Bhattacharya, Soma; Zaloshnja, Eduard; Taylor, Dexter; Bahar, Geni; David, Iuliana
2011-01-01
We estimated how much the Federal government and state/local government pay for different kinds of crashes in the United States. Government costs include reductions in an array of public services (emergency, incident management, vocational rehabilitation, coroner court processing of liability litigation), medical payments, social safety net assistance to the injured and their families, and taxes foregone because victims miss work. Government also pays when its employees crash while working and covers fringe benefits for crash-involved employees and their benefit-eligible dependents in non-work hours. We estimated government shares of crash costs by component. We applied those estimates to existing US Department of Transportation estimates of crash costs to society and employers. Government pays an estimated $35 billion annually because of crashes, an estimated 12.6% of the economic cost of crashes (Federal 7.1%, State/local 5.5%). Government bears a higher percentage of the monetary costs of injury crashes than fatal crashes or crashes involving property damage only. Government is increasingly recovering the medical cost of crashes from auto insurers. Nevertheless, medical costs and income and sales tax losses account for 75% of government's crash costs. For State/local government to break even on a 100%-State funded investment in road safety, the intervention would need to have an unrealistically high benefit-cost ratio of 34. Government invests in medical treatment of illness to save lives and improve quality of life. Curing a child's leukemia, for example, is not less costly than leaving that leukemia untreated. Safety should not be held to a different standard. PMID:22105409
af Wåhlberg, Anders; Freeman, James; Watson, Barry; Watson, Angela
2016-01-01
Background Traffic offences have been considered an important predictor of crash involvement, and have often been used as a proxy safety variable for crashes. However the association between crashes and offences has never been meta-analysed and the population effect size never established. Research is yet to determine the extent to which this relationship may be spuriously inflated through systematic measurement error, with obvious implications for researchers endeavouring to accurately identify salient factors predictive of crashes. Methodology and Principal Findings Studies yielding a correlation between crashes and traffic offences were collated and a meta-analysis of 144 effects drawn from 99 road safety studies conducted. Potential impact of factors such as age, time period, crash and offence rates, crash severity and data type, sourced from either self-report surveys or archival records, were considered and discussed. After weighting for sample size, an average correlation of r = .18 was observed over the mean time period of 3.2 years. Evidence emerged suggesting the strength of this correlation is decreasing over time. Stronger correlations between crashes and offences were generally found in studies involving younger drivers. Consistent with common method variance effects, a within country analysis found stronger effect sizes in self-reported data even controlling for crash mean. Significance The effectiveness of traffic offences as a proxy for crashes may be limited. Inclusion of elements such as independently validated crash and offence histories or accurate measures of exposure to the road would facilitate a better understanding of the factors that influence crash involvement. PMID:27128093
Restraint use law enforcement intervention in Latino communities.
Schaechter, Judy; Uhlhorn, Susan B
2011-11-01
Motor vehicle crashes are the leading cause of death for U.S. Latinos aged 1 to 35 years. Restraint use is an effective means of prevention of motor vehicle crash injury. Effective interventions to raise restraint use include the following: legislation, law enforcement, education, and equipment distribution. The effects of law enforcement interventions in Latino immigrant communities are understudied. We measured the community-level effect of a combined intervention that included warnings and citations phase enforcement in Latino communities. We designed and implemented in two of three Latino-majority communities a multicomponent intervention consisting of a community awareness campaign, restraint use education with equipment distribution, and a two-staged law enforcement intervention. Restraint use observations were conducted in all three communities at baseline, after the warnings phase and again after the citations phase of the intervention were completed. The combined intervention of community awareness, education, child passenger restraint distribution, and law enforcement focused on educational traffic stops with incentives and warnings was associated with a significant increase in both driver and child passenger restraint use in one intervention community, but only driver restraint increased to a level of significance in the other intervention community; significant increase was also noted among nonintervention drivers. The citations phase of the intervention did not result in a significant increase in restraint use and was complicated by interruptions due to unlicensed drivers. The combined effort of community awareness, education, equipment distribution and law enforcement intervention that included incentives and warnings may be effective at increasing seat belt use in Latino communities without the need for citations.
Crash probability estimation via quantifying driver hazard perception.
Li, Yang; Zheng, Yang; Wang, Jianqiang; Kodaka, Kenji; Li, Keqiang
2018-07-01
Crash probability estimation is an important method to predict the potential reduction of crash probability contributed by forward collision avoidance technologies (FCATs). In this study, we propose a practical approach to estimate crash probability, which combines a field operational test and numerical simulations of a typical rear-end crash model. To consider driver hazard perception characteristics, we define a novel hazard perception measure, called as driver risk response time, by considering both time-to-collision (TTC) and driver braking response to impending collision risk in a near-crash scenario. Also, we establish a driving database under mixed Chinese traffic conditions based on a CMBS (Collision Mitigation Braking Systems)-equipped vehicle. Applying the crash probability estimation in this database, we estimate the potential decrease in crash probability owing to use of CMBS. A comparison of the results with CMBS on and off shows a 13.7% reduction of crash probability in a typical rear-end near-crash scenario with a one-second delay of driver's braking response. These results indicate that CMBS is positive in collision prevention, especially in the case of inattentive drivers or ole drivers. The proposed crash probability estimation offers a practical way for evaluating the safety benefits in the design and testing of FCATs. Copyright © 2017 Elsevier Ltd. All rights reserved.
Ehrlich, Peter F; Brown, J Kristine; Sochor, Mark R; Wang, Stewart C; Eichelberger, Martin E
2006-11-01
Motor vehicle crashes account for more than 50% of pediatric injuries. Triage of pediatric patients to appropriate centers can be based on the crash/injury characteristics. Pediatric motor vehicle crash/injury characteristics can be determined from an in vitro laboratory using child crash dummies. However, to date, no detailed data with respect to outcomes and crash mechanism have been presented with a pediatric in vivo model. The Crash Injury Research Engineering Network is comprised of 10 level 1 trauma centers. Crashes were examined with regard to age, crash severity (DeltaV), crash direction, restraint use, and airbag deployment. Multiple logistic regression analysis was performed with Injury Severity Score (ISS) and Glasgow Coma Scale (GCS) as outcomes. Standard age groupings (0-4, 5-9, 10-14, and 15-18) were used. The database is biases toward a survivor population with few fatalities. Four hundred sixty-one motor vehicle crashes with 2500 injuries were analyzed (242 boys, 219 girls). Irrespective of age, DeltaV > 30 mph resulted in increased ISS and decreased GCS (eg, for 0-4 years, DeltaV < 30: ISS = 10, GCS = 13.5 vs DeltaV > 30: ISS = 19.5, GCS = 10.6; P < .007, < .002, respectively). Controlling for DeltaV, children in lateral crashes had increased ISS and decreased GCS versus those in frontal crashes. Airbag deployment was protective for children 15 to 18 years old and resulted in a lower ISS and higher GCS (odds ratio, 2.1; 95% confidence interval, 0.9-4.6). Front-seat passengers suffered more severe (ISS > 15) injuries than did backseat passengers (odds ratio, 1.7; 95% confidence interval, 0.7-3.4). A trend was noted for children younger than 12 years sitting in the front seat to have increased ISS and decreased GCS with airbag deployment but was limited by case number. A reproducible pattern of increased ISS and lower GCS characterized by high severity, lateral crashes in children was noted. Further analysis of the specific injuries as a function and the crash characteristic can help guide management and prevention strategies.
Dezman, Zachary; de Andrade, Luciano; Vissoci, Joao Ricardo; El-Gabri, Deena; Johnson, Abree; Hirshon, Jon Mark; Staton, Catherine A.
2017-01-01
Introduction Road traffic injuries are a leading killer of youth (aged 15–29) and are projected to be the 7th leading cause of death by 2030. To better understand road traffic crash locations and characteristics in the city of Baltimore, we used police and census data, to describe the epidemiology, hotspots, and modifiable risk factors involved to guide further interventions. Materials and methods Data on all crashes in Baltimore City from 2009 to 2013 were made available from the Maryland Automated Accident Reporting System. Socioeconomic data collected by the US CENSUS 2010 were obtained. A time series analysis was conducted using an ARIMA model. We analyzed the geographical distribution of traffic crashes and hotspots using exploratory spatial data analysis and spatial autocorrelation. Spatial regression was performed to evaluate the impact of socioeconomic indicators on hotspots. Results In Baltimore City, between 2009 and 2013, there were a total of 100,110 crashes reported, with 1% of crashes considered severe. Of all crashes, 7% involved vulnerable road users and 12% had elderly or youth involvement. Reasons for crashes included: distracted driving (31%), speeding (6%), and alcohol or drug use (5%). After 2010, we observed an increasing trend in all crashes especially from March to June. Distracted driving then youth and elderly drivers were consistently the highest risk factors over time. Multivariate spatial regression model including socioeconomic indicators and controlling for age, gender and population size did not show a distinct predictor of crashes explaining only 20% of the road crash variability, indicating crashes are not geographically explained by socioeconomic indicators alone. Conclusion In Baltimore City, road traffic crashes occurred predominantly in the high density center of the city, involved distracted driving and extremes of age with an increase in crashes from March to June. There was no association between socioeconomic variables where crashes occurred and hotspots. In depth analysis of how modifiable risk factors are impacted by geospatial characteristics and the built environment is warranted in Baltimore to tailor interventions. PMID:27614672
Dezman, Zachary; de Andrade, Luciano; Vissoci, Joao Ricardo; El-Gabri, Deena; Johnson, Abree; Hirshon, Jon Mark; Staton, Catherine A
2016-11-01
Road traffic injuries are a leading killer of youth (aged 15-29) and are projected to be the 7th leading cause of death by 2030. To better understand road traffic crash locations and characteristics in the city of Baltimore, we used police and census data, to describe the epidemiology, hotspots, and modifiable risk factors involved to guide further interventions. Data on all crashes in Baltimore City from 2009 to 2013 were made available from the Maryland Automated Accident Reporting System. Socioeconomic data collected by the US CENSUS 2010 were obtained. A time series analysis was conducted using an ARIMA model. We analyzed the geographical distribution of traffic crashes and hotspots using exploratory spatial data analysis and spatial autocorrelation. Spatial regression was performed to evaluate the impact of socioeconomic indicators on hotspots. In Baltimore City, between 2009 and 2013, there were a total of 100,110 crashes reported, with 1% of crashes considered severe. Of all crashes, 7% involved vulnerable road users and 12% had elderly or youth involvement. Reasons for crashes included: distracted driving (31%), speeding (6%), and alcohol or drug use (5%). After 2010, we observed an increasing trend in all crashes especially from March to June. Distracted driving then youth and elderly drivers were consistently the highest risk factors over time. Multivariate spatial regression model including socioeconomic indicators and controlling for age, gender and population size did not show a distinct predictor of crashes explaining only 20% of the road crash variability, indicating crashes are not geographically explained by socioeconomic indicators alone. In Baltimore City, road traffic crashes occurred predominantly in the high density center of the city, involved distracted driving and extremes of age with an increase in crashes from March to June. There was no association between socioeconomic variables where crashes occurred and hotspots. In depth analysis of how modifiable risk factors are impacted by geospatial characteristics and the built environment is warranted in Baltimore to tailor interventions. Copyright © 2016 Elsevier Ltd. All rights reserved.
DOT National Transportation Integrated Search
2007-01-01
Idaho Traffic Crashes 2007 provides an annual description of motor vehicle crash characteristics for : crashes that have occurred within the State of Idaho. This document is used by state and local : transportation, law enforcement, health, and other...
Crash countermeasure and mobility effects.
DOT National Transportation Integrated Search
2012-04-19
The Michigan Department of Transportation (MDOT) has undertaken several initiatives to reduce crashes on its roadway network. In 2009, there were 2,201 reported crashes involving pedestrians and 866 reported crashes involving bicyclists in Michigan. ...
Traffic crash statistics report, 2005
DOT National Transportation Integrated Search
2006-01-01
The information contained in this Traffic Crash Statistics booklet is extracted from law enforcement : agency long-form reports of traffic crashes. A law enforcement officer must submit a long-form : crash report when investigating: : Motor vehic...
DOT National Transportation Integrated Search
2007-02-01
This annual edition of Large Truck Crash Facts contains descriptive statistics about fatal, injury, and property damage only crashes involving large trucks in 2005. Selected crash statistics on passenger vehicles are also presented for comparison pur...
Cell phone use and traffic crash risk: a culpability analysis.
Asbridge, Mark; Brubacher, Jeff R; Chan, Herbert
2013-02-01
The use of a cell phone or communication device while driving is illegal in many jurisdictions, yet evidence evaluating the crash risk associated with cell phone use in naturalistic settings is limited. This article aims to determine whether cell phone use while driving increases motor vehicle crash culpability. Method Drivers involved in crashes where police reported cell phone use (n = 312) and propensity matched drivers (age, sex, suspect alcohol/drug impairment, crash type, date, time of day, geographical location) without cell phone use (n = 936) were drawn from Insurance Corporation of British Columbia Traffic Accident System data. A standardized scoring tool, modified to account for Canadian driving conditions, was used to determine crash culpability from police reports on all drivers from the crashes. The association between crash culpability and cell phone use was determined, with additional subgroup analyses based on crash severity, driver characteristics and type of licence. A comparison of crashes with vs without cell phones revealed an odds ratio of 1.70 (95% confidence interval 1.22-2.36; P = 0.002). This association was consistent after adjustment for matching variables and other covariates. Subgroup analyses demonstrated an association for male drivers, unimpaired drivers, injured and non-injured drivers, and for drivers aged between 26 and 65 years. Crash culpability was found to be significantly associated with cell phone use by drivers, increasing the odds of a culpable crash by 70% compared with drivers who did not use a cell phone. This increased risk was particularly high for middle-aged drivers.
Impact of pavement conditions on crash severity.
Li, Yingfeng; Liu, Chunxiao; Ding, Liang
2013-10-01
Pavement condition has been known as a key factor related to ride quality, but it is less clear how exactly pavement conditions are related to traffic crashes. The researchers used Geographic Information System (GIS) to link Texas Department of Transportation (TxDOT) Crash Record Information System (CRIS) data and Pavement Management Information System (PMIS) data, which provided an opportunity to examine the impact of pavement conditions on traffic crashes in depth. The study analyzed the correlation between several key pavement condition ratings or scores and crash severity based on a large number of crashes in Texas between 2008 and 2009. The results in general suggested that poor pavement condition scores and ratings were associated with proportionally more severe crashes, but very poor pavement conditions were actually associated with less severe crashes. Very good pavement conditions might induce speeding behaviors and therefore could have caused more severe crashes, especially on non-freeway arterials and during favorable driving conditions. In addition, the results showed that the effects of pavement conditions on crash severity were more evident for passenger vehicles than for commercial vehicles. These results provide insights on how pavement conditions may have contributed to crashes, which may be valuable for safety improvement during pavement design and maintenance. Readers should notice that, although the study found statistically significant effects of pavement variables on crash severity, the effects were rather minor in reality as suggested by frequency analyses. Copyright © 2013 Elsevier Ltd. All rights reserved.
Fatal crashes involving large numbers of vehicles and weather.
Wang, Ying; Liang, Liming; Evans, Leonard
2017-12-01
Adverse weather has been recognized as a significant threat to traffic safety. However, relationships between fatal crashes involving large numbers of vehicles and weather are rarely studied according to the low occurrence of crashes involving large numbers of vehicles. By using all 1,513,792 fatal crashes in the Fatality Analysis Reporting System (FARS) data, 1975-2014, we successfully described these relationships. We found: (a) fatal crashes involving more than 35 vehicles are most likely to occur in snow or fog; (b) fatal crashes in rain are three times as likely to involve 10 or more vehicles as fatal crashes in good weather; (c) fatal crashes in snow [or fog] are 24 times [35 times] as likely to involve 10 or more vehicles as fatal crashes in good weather. If the example had used 20 vehicles, the risk ratios would be 6 for rain, 158 for snow, and 171 for fog. To reduce the risk of involvement in fatal crashes with large numbers of vehicles, drivers should slow down more than they currently do under adverse weather conditions. Driver deaths per fatal crash increase slowly with increasing numbers of involved vehicles when it is snowing or raining, but more steeply when clear or foggy. We conclude that in order to reduce risk of involvement in crashes involving large numbers of vehicles, drivers must reduce speed in fog, and in snow or rain, reduce speed by even more than they already do. Copyright © 2017 National Safety Council and Elsevier Ltd. All rights reserved.
Moradi, Ali; Soori, Hamid; Kavousi, Amir; Eshghabadi, Farshid; Jamshidi, Ensiyeh; Zeini, Salahdien
2016-01-01
Background: More than 20% of deaths from traffic crashes are related to pedestrians. This figure in Tehran, the capital of Iran, reaches to 40%. This study aimed to determine the high-risk areas and spatially analyze the traffic crashes, causing death to pedestrians in Tehran. Methods: Mapping was used to display the distribution of the crashes. Determining the distribution pattern of crashes and the hot spots/ low-risk areas were done, using Moran’s I index and Getis-Ord G, respectively. Results: A total of 198 crashes were studied; 92 of which, (46.4%) occurred in 2013 to 2014 and other 106 cases (63.6%) occurred in 2014 to 2015. The highest and the lowest frequency of crashes was related to January (26 cases) and June (10 cases), respectively. One hundred fifty- eight cases (79.8%) of crashes occurred in Tehran highways. Moran’s index showed that the studied traffic crashes had a cluster distribution (p<0.001). Getis- Ord General G index indicated that the distribution of hot and cold spots of the studied crashes was statistically significant (p<0.001). Conclusion: The majority of traffic crashes causing death to pedestrians occurred in highways located in the main entrances and exits of Tehran. Given the important role of environmental factors in the occurrence of traffic crashes related to pedestrians, identification of these factors requires more studies with casual inferences. PMID:28210615
NASA Astrophysics Data System (ADS)
Gill, G.; Sakrani, T.; Cheng, W.; Zhou, J.
2017-09-01
Many studies have utilized the spatial correlations among traffic crash data to develop crash prediction models with the aim to investigate the influential factors or predict crash counts at different sites. The spatial correlation have been observed to account for heterogeneity in different forms of weight matrices which improves the estimation performance of models. But very rarely have the weight matrices been compared for the prediction accuracy for estimation of crash counts. This study was targeted at the comparison of two different approaches for modelling the spatial correlations among crash data at macro-level (County). Multivariate Full Bayesian crash prediction models were developed using Decay-50 (distance-based) and Queen-1 (adjacency-based) weight matrices for simultaneous estimation crash counts of four different modes: vehicle, motorcycle, bike, and pedestrian. The goodness-of-fit and different criteria for accuracy at prediction of crash count reveled the superiority of Decay-50 over Queen-1. Decay-50 was essentially different from Queen-1 with the selection of neighbors and more robust spatial weight structure which rendered the flexibility to accommodate the spatially correlated crash data. The consistently better performance of Decay-50 at prediction accuracy further bolstered its superiority. Although the data collection efforts to gather centroid distance among counties for Decay-50 may appear to be a downside, but the model has a significant edge to fit the crash data without losing the simplicity of computation of estimated crash count.
Identification of CRASH, a gene deregulated in gynecological tumors.
Evtimova, Vesna; Zeillinger, Robert; Kaul, Sepp; Weidle, Ulrich H
2004-01-01
We have identified CRASH, a human asparaginase-like protein which is composed of 308 amino acids and exhibits 32% homology to human aspartylglucosaminadase at the amino acid level. Database analysis revealed that the gene corresponding to CRASH is composed of 7 exons and 6 introns. Steady-state level of CRASH mRNA was found to be increased in 5 cell lines derived from metastatic lesions compared with 2 cell lines derived from primary mammary carcinoma and HMEC (human mammary epithelial cells). We found that the mRNA level of CRASH correlates with the metastatic propensity of several isogenic human colon cancer and pancreatic carcinoma cell lines. CRASH corresponds to a recently identified sperm autoantigen and furthermore we have demonstrated inducibility of CRASH mRNA by androgen and progesterone. Investigation of several types of human cancers and their corresponding normal tissues revealed high levels of CRASH mRNA in uterine, mammary and ovarian tumors compared with the corresponding normal tissues. CRASH mRNA expression was analysed in breast cancer samples with disclosed clinico-pathological features and corresponding normal tissues. The levels of CRASH mRNA were significantly up-regulated in tumors compared with normal breast tissues and correlate with lack of estrogen receptor expression of the tumors.
Prevalence and factors associated with road traffic crash among taxi drivers in Hanoi, Vietnam.
La, Quang Ngoc; Lee, Andy H; Meuleners, Lynn B; Van Duong, Dat
2013-01-01
Injury due to road traffic crash is a major cause of ill health and premature deaths in developing countries. Taxis provide a main mode of public transport in Vietnam but there has been little research on the risk of crash for taxi drivers. This retrospective study collected information on taxi crashes for the period 2006-2009 by interviewing drivers from five taxi companies in Hanoi, Vietnam, using a structured questionnaire. Of the total 1214 participants recruited, 276 drivers reported at least one crash, giving an overall crash prevalence of 22.7%. Among the crashed group, 50 drivers (18.1%) were involved in two to four crashes. Logistic regression analysis further identified age of driver, type of driving licence, employment status, perceived sufficiency of income, seat-belt usage, and traffic infringement history to be significantly associated with the crash risk. Further prospective and qualitative studies are recommended to provide detailed crash characteristics as well as behaviour and perception of taxi drivers, so that an effective intervention can be developed to improve road safety and to prevent injury of these commercial drivers. Copyright © 2012 Elsevier Ltd. All rights reserved.
Active muscle response using feedback control of a finite element human arm model.
Östh, Jonas; Brolin, Karin; Happee, Riender
2012-01-01
Mathematical human body models (HBMs) are important research tools that are used to study the human response in car crash situations. Development of automotive safety systems requires the implementation of active muscle response in HBM, as novel safety systems also interact with vehicle occupants in the pre-crash phase. In this study, active muscle response was implemented using feedback control of a nonlinear muscle model in the right upper extremity of a finite element (FE) HBM. Hill-type line muscle elements were added, and the active and passive properties were assessed. Volunteer tests with low impact loading resulting in elbow flexion motions were performed. Simulations of posture maintenance in a gravity field and the volunteer tests were successfully conducted. It was concluded that feedback control of a nonlinear musculoskeletal model can be used to obtain posture maintenance and human-like reflexive responses in an FE HBM.
Road traffic crashes among farm vehicle drivers in southern China: A cross-sectional survey.
Zhang, Xujun; Yang, Yaming; Chen, Yu; Yao, Hongyan; Wu, Ming; Cui, Mengjing; Li, Yang; Hu, Jie; Zhang, Cong; Li, Zhen; Stallones, Lorann; Xiang, Huiyun
2017-01-02
The objective of this study was to identify the prevalence and potential risk factors of farm vehicle-related road traffic crashes among farm vehicle drivers in southern China. A cross-sectional study was used to interview 1,422 farm vehicle drivers in southern China. Farm vehicle-related road traffic crashes that occurred from December 2013 to November 2014 were investigated. Data on farm vehicle-related road traffic crashes and related factors were collected by face-to-face interviews. The prevalence of farm vehicle-related road traffic crashes among the investigated drivers was 7.2%. Farm vehicle-related road traffic crashes were significantly associated with self-reported vision problem (adjusted odds ratio [AOR] = 6.48, 95% confidence interval [CI], 3.86-10.87), self-reported sleep disorders (AOR = 10.03, 95% CI, 6.28-15.99), self-reported stress (AOR = 20.47, 95% CI, 9.96-42.08), reported history of crashes (AOR = 5.40, 95% CI, 3.47-8.42), reported history of drunk driving (AOR = 5.07, 95% CI, 2.97-8.65), and reported history of fatigued driving (AOR = 5.72, 95% CI, 3.73-8.78). The number of road traffic crashes was highest in the daytime and during harvest season. In over 96% of farm vehicle-related road traffic crashes, drivers were believed to be responsible for the crash. Major crash-causing factors included improper driving, careless driving, violating of traffic signals or signs, and being in the wrong lane. Findings of this study suggest that farm vehicle-related road traffic crashes have become a burgeoning public health problem in China. Programs need to be developed to prevent farm vehicle-related road traffic crashes in this emerging country.
Epidemiology of pedestrian-MVCs by road type in Cluj, Romania.
Hamann, Cara; Peek-Asa, Corinne; Rus, Diana
2015-04-01
Pedestrian-motor vehicle (PMV) crash rates in Romania are among the highest in all of Europe. The purpose of this study was to examine the characteristics of pedestrian-MVCs in Cluj County, Romania, on the two major types of roadways: national or local. Cluj County police crash report data from 2010 were used to identify pedestrian, driver and crash characteristics of pedestrian-MVCs. Crashes with available location data were geocoded and road type (national or local) for each crash was determined. Distributions of crash characteristics were examined by road type and multivariable logistic regression models were built to determine predictors of crash road type. Crashes occurring on national roads involved more teenagers and adults, while those on local roads involved more young children (0-12) and older adults (65+) (p<0.01). Crashes on national roads were more likely to have marked pedestrian crossings and shoulders compared with local crashes. Pedestrian-MVCs that involved a moving violation by the motorist were more likely to occur on national roadways (adjusted OR=1.93, 95% CI 1.07 to 3.49). Pedestrian-MVCs pose a considerable health burden in Romania. Results from this study suggest that factors leading to PMV crashes on national roads are more likely to involve driver-related causes compared with local roads. Intervention priorities to reduce pedestrian crashes on national roads should be directed towards driver behaviour on national roads. Further examination of driver and pedestrian behaviours related to crash risk on both national and local roads, such as distraction and speeding, is warranted. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Geographic Region, Weather, Pilot Age and Air Carrier Crashes: a Case-Control Study
Li, Guohua; Pressley, Joyce C.; Qiang, Yandong; Grabowski, Jurek G.; Baker, Susan P.; Rebok, George W.
2009-01-01
Background Information about risk factors of aviation crashes is crucial for developing effective intervention programs. Previous studies assessing factors associated with crash risk were conducted primarily in general aviation, air taxis and commuter air carriers. Methods A matched case-control design was used to examine the associations of geographic region, basic weather condition, and pilot age with the risk of air carrier (14 CFR Part 121) crash involvement. Cases (n=373) were air carrier crashes involving aircraft made by Boeing, McDonnell Douglas, and Airbus, recorded in the National Transportation Safety Board’s aviation crash database during 1983 through 2002, and controls (n=746) were air carrier incidents involving aircraft of the same three makes selected at random from the Federal Aviation Administration’s aviation incident database. Each case was matched with two controls on the calendar year when the index crash occurred. Conditional logistic regression was used for statistical analysis. Results With adjustment for basic weather condition, pilot age, and total flight time, the risk of air carrier crashes in Alaska was more than three times the risk for other regions [adjusted odds ratio (OR) 3.18, 95% confidence interval (CI) 1.35 – 7.49]. Instrument meteorological conditions were associated with an increased risk for air carrier crashes involving pilot error (adjusted OR 2.26, 95% CI 1.15 – 4.44) and a decreased risk for air carrier crashes without pilot error (adjusted OR 0.57, 95% CI 0.40 – 0.87). Neither pilot age nor total flight time was significantly associated with the risk of air carrier crashes. Conclusions The excess risk of air carrier crashes in Alaska and the effect of adverse weather on pilot-error crashes underscore the importance of environmental hazards in flight safety. PMID:19378910
Geographic region, weather, pilot age, and air carrier crashes: a case-control study.
Li, Guohua; Pressley, Joyce C; Qiang, Yandong; Grabowski, Jurek G; Baker, Susan P; Rebok, George W
2009-04-01
Information about risk factors of aviation crashes is crucial for developing effective intervention programs. Previous studies assessing factors associated with crash risk were conducted primarily in general aviation, air taxis, and commuter air carriers. A matched case-control design was used to examine the associations of geographic region, basic weather condition, and pilot age with the risk of air carrier (14 CFR Part 121) crash involvement. Cases (N = 373) were air carrier crashes involving aircraft made by Boeing, McDonnell Douglas, and Airbus recorded in the National Transportation Safety Board's aviation crash database during 1983 through 2002, and controls (N = 746) were air carrier incidents involving aircraft of the same three makes selected at random from the Federal Aviation Administration's aviation incident database. Each case was matched with two controls on the calendar year when the index crash occurred. Conditional logistic regression was used for statistical analysis. With adjustment for basic weather condition, pilot age, and total flight time, the risk of air carrier crashes in Alaska was more than three times the risk for other regions ladjusted odds ratio (OR) 3.18, 95% confidence interval (CI) 1.35-7.49]. Instrument meteorological conditions were associated with an increased risk for air carrier crashes involving pilot error (adjusted OR 2.26, 95% CI 1.15-4.44) and a decreased risk for air carrier crashes without pilot error (adjusted OR 0.60, 95% CI 0.37-0.96). Neither pilot age nor total flight time were significantly associated with the risk of air carrier crashes. The excess risk of air carrier crashes in Alaska and the effect of adverse weather on pilot-error crashes underscore the importance of environmental hazards in flight safety.
Bajaj, Jasmohan S; Saeian, Kia; Schubert, Christine M; Hafeezullah, Muhammad; Franco, Jose; Varma, Rajiv R; Gibson, Douglas P; Hoffmann, Raymond G; Stravitz, R Todd; Heuman, Douglas M; Sterling, Richard K; Shiffman, Mitchell; Topaz, Allyne; Boyett, Sherry; Bell, Debulon; Sanyal, Arun J
2009-01-01
Patients with minimal hepatic encephalopathy (MHE) have impaired driving skills, but association of MHE with motor vehicle crashes is unclear. Standard psychometric tests (SPT) or inhibitory control test (ICT) can be used to diagnose MHE. The aim was to determine the association of MHE with crashes and traffic violations over the preceding year and on 1-year follow-up. Cirrhotics were diagnosed with MHE by ICT (MHEICT) and SPT (MHESPT). Self and department-of-transportation (DOT)-reports were used to determine crashes and violations over the preceding year. Agreement between self and DOT-reports was analyzed. Patients then underwent 1 year follow-up for crash/violation occurrence. Crashes in those with/without MHEICT and MHESPT were compared. 167 cirrhotics had DOT-reports, of which 120 also had self-reports. A significantly higher proportion of MHEICT cirrhotics experienced crashes in the preceding year compared to those without MHE by self-report (17% vs. 0%, p=0.0004) and DOT-reports (17% vs. 3%, p=0.004, relative risk:5.77). SPT did not differentiate between those with/without crashes. A significantly higher proportion of patients with crashes had MHEICT compared to MHESPT, both self-reported (100% vs. 50%, p=0.03) and DOT-reported (89% vs. 44%, p=0.01). There was excellent agreement between self and DOT-reports for crashes and violations (Kappa 0.90 and 0.80). 109 patients were followed prospectively. MHEICT patients had a significantly higher future crashes/violations compared to those without (22% vs. 7%, p=0.03) but MHESPT did not. MHEICT (Odds ratio:4.51) and prior year crash/violation (Odds ratio:2.96) were significantly associated with future crash/violation occurrence. PMID:19670416
Analysis of the frequency and severity of rear-end crashes in work zones.
Qi, Yi; Srinivasan, Raghavan; Teng, Hualiang; Baker, Robert
2013-01-01
The objective of this study was to identify the factors that influence the frequency and severity of rear-end crashes in work zones because rear-end crashes represent a significant proportion of crashes that occur in work zones. Truncated count data models were developed to identify influencing factors on the frequency of read-end crashes in work zones and ordered probit models were developed to evaluate influencing factors on the severity of rear-end crashes in work zones. Most of the variables identified in this study for these 2 models were significant at the 95 percent level. The statistics for models indicate that the 2 developed models are appropriate compared to alternative models. Major findings related to the frequency of rear-end crashes include the following: (1) work zones for capacity and pavement improvements have the highest frequency compared to other types of work zones; (2) work zones controlled by flaggers are associated with more rear-end crashes compared to those controlled by arrow boards; and (3) work zones with alternating one-way traffic tended to have more rear-end crashes compared to those with lane shifts. Major findings related to the severity of the rear-end crashes include the following: (1) rear-end crashes associated with alcohol, night, pedestrians, and roadway defects are more severe, and those associated with careless backing, stalled vehicles, slippery roadways, and misunderstanding flagging signals are less severe; (2) truck involvement and a large number of vehicles in a crash are both associated with increased severity, and (3) rear-end crashes that happened in work zones for bridge, capacity, and pavement are likely to be more severe than others.
Analysis of work zone rear-end crash risk for different vehicle-following patterns.
Weng, Jinxian; Meng, Qiang; Yan, Xuedong
2014-11-01
This study evaluates rear-end crash risk associated with work zone operations for four different vehicle-following patterns: car-car, car-truck, truck-car and truck-truck. The deceleration rate to avoid the crash (DRAC) is adopted to measure work zone rear-end crash risk. Results show that the car-truck following pattern has the largest rear-end crash risk, followed by truck-truck, truck-car and car-car patterns. This implies that it is more likely for a car which is following a truck to be involved in a rear-end crash accident. The statistical test results further confirm that rear-end crash risk is statistically different between any two of the four patterns. We therefore develop a rear-end crash risk model for each vehicle-following pattern in order to examine the relationship between rear-end crash risk and its influencing factors, including lane position, the heavy vehicle percentage, lane traffic flow and work intensity which can be characterized by the number of lane reductions, the number of workers and the amount of equipment at the work zone site. The model results show that, for each pattern, there will be a greater rear-end crash risk in the following situations: (i) heavy work intensity; (ii) the lane adjacent to work zone; (iii) a higher proportion of heavy vehicles and (iv) greater traffic flow. However, the effects of these factors on rear-end crash risk are found to vary according to the vehicle-following patterns. Compared with the car-car pattern, lane position has less effect on rear-end crash risk in the car-truck pattern. The effect of work intensity on rear-end crash risk is also reduced in the truck-car pattern. Copyright © 2014 Elsevier Ltd. All rights reserved.
Omitted variable bias in crash reduction factors.
DOT National Transportation Integrated Search
2015-09-01
Transportation planners and traffic engineers are increasingly turning to crash reduction factors to evaluate changes in road : geometric and design features in order to reduce crashes. Crash reduction factors are typically estimated based on segment...
DOT National Transportation Integrated Search
2009-01-01
Idaho Traffic Crashes 2009 provides an annual description of motor vehicle crash characteristics for : crashes that have occurred on public roads within the State of Idaho. This document is used by state and : local transportation, law enforcement, h...
DOT National Transportation Integrated Search
2008-01-01
Idaho Traffic Crashes 2008 provides an annual description of motor vehicle crash characteristics for : crashes that have occurred on public roads within the State of Idaho. This document is used by state and : local transportation, law enforcement, h...
2007 South Dakota motor vehicle traffic crash summary
DOT National Transportation Integrated Search
2008-01-01
The Motor Vehicle Traffic Crash Summary is divided into two main sections, Historical : Trends and 2007 Motor Vehicle Traffic Crash Profile. The Historical Trend section : provides information on alcohol involvement in motor vehicle crashes, severity...
2006 South Dakota motor vehicle traffic crash summary
DOT National Transportation Integrated Search
2007-05-01
The Motor Vehicle Traffic Crash Summary is divided into two main sections, Historical : Trends and 2006 Motor Vehicle Traffic Crash Profile. The Historical Trend section : provides information on alcohol involvement in motor vehicle crashes, severity...
2008 South Dakota motor vehicle traffic crash summary
DOT National Transportation Integrated Search
2009-06-01
The Motor Vehicle Traffic Crash Summary is divided into two main sections, Historical : Trends and 2008 Motor Vehicle Traffic Crash Profile. The Historical Trend section : provides information on alcohol involvement in motor vehicle crashes, severity...
2009 South Dakota motor vehicle traffic crash summary
DOT National Transportation Integrated Search
2010-06-01
The Motor Vehicle Traffic Crash Summary is divided into two main sections, Historical : Trends and 2009 Motor Vehicle Traffic Crash Profile. The Historical Trend section : provides information on alcohol involvement in motor vehicle crashes, severity...
Objective tests for forward looking pedestrian crash avoidance/mitigation systems.
DOT National Transportation Integrated Search
2014-06-01
This report documents the work completed by the Crash Avoidance Metrics Partnership (CAMP) Crash Imminent Braking : (CIB) Consortium during the project titled Objective Tests for Forward Looking Pedestrian Crash Avoidance/Mitigation : Systems. ...
Chimba, Deo; Kutela, Boniphace
2014-09-01
Extent of secondary crashes derived from primary incidents involving abandoned and disabled vehicles are presented in this paper. Using years 2004 to 2010 incident and crash data on selected Tennessee freeways, the study identified secondary crashes that resulted from disabled and abandoned vehicle primary incidents. The relationship between time and distance gaps before the secondary crash with respect to individual incident characteristics were evaluated through descriptive statistics and linear regression. The time and distance gap analysis indicated that a large portion of secondary crashes occurred within 20 min after the primary incidents and within a distance of 0.5 miles upstream. While 76% of incidents involved shoulder, most secondary crashes were related to the closing of right lanes. Overall, 58% of the secondary crashes occurred within 30 min after the occurrence of the primary incidents. Most of the vehicles in the incidents that involved towing and caused secondary crashes were towed or removed out of the travel way within 60 min from the time of occurrence. The study found that most (95%) secondary crashes were property damage only (PDO), while 49% were rear-end crashes. The negative binomial model was used to evaluate the impact of roadway geometry and traffic factors associated with frequency of these secondary crashes. It was found that the posted speed limit, congested segments, segments with high percentages of trucks, and peak hour volumes increased the likelihood of secondary crash occurrence. Roadway segments with wider medians, shoulders, and multilanes decrease the likelihood of secondary crashes caused by abandoned and disabled vehicles as the primary incidents. Practical applications The paper recommends that wider shoulders be provided on any section of freeway to accommodate abandoned or disabled vehicles to avoid blocking of travel lane(s). Copyright © 2014 National Safety Council and Elsevier Ltd. All rights reserved.
Repeatability study of replicate crash tests: A signal analysis approach.
Seppi, Jeremy; Toczyski, Jacek; Crandall, Jeff R; Kerrigan, Jason
2017-10-03
To provide an objective basis on which to evaluate the repeatability of vehicle crash test methods, a recently developed signal analysis method was used to evaluate correlation of sensor time history data between replicate vehicle crash tests. The goal of this study was to evaluate the repeatability of rollover crash tests performed with the Dynamic Rollover Test System (DRoTS) relative to other vehicle crash test methods. Test data from DRoTS tests, deceleration rollover sled (DRS) tests, frontal crash tests, frontal offset crash tests, small overlap crash tests, small overlap impact (SOI) crash tests, and oblique crash tests were obtained from the literature and publicly available databases (the NHTSA vehicle database and the Insurance Institute for Highway Safety TechData) to examine crash test repeatability. Signal analysis of the DRoTS tests showed that force and deformation time histories had good to excellent repeatability, whereas vehicle kinematics showed only fair repeatability due to the vehicle mounting method for one pair of tests and slightly dissimilar mass properties (2.2%) in a second pair of tests. Relative to the DRS, the DRoTS tests showed very similar or higher levels of repeatability in nearly all vehicle kinematic data signals with the exception of global X' (road direction of travel) velocity and displacement due to the functionality of the DRoTS fixture. Based on the average overall scoring metric of the dominant acceleration, DRoTS was found to be as repeatable as all other crash tests analyzed. Vertical force measures showed good repeatability and were on par with frontal crash barrier forces. Dynamic deformation measures showed good to excellent repeatability as opposed to poor repeatability seen in SOI and oblique deformation measures. Using the signal analysis method as outlined in this article, the DRoTS was shown to have the same or better repeatability of crash test methods used in government regulatory and consumer evaluation test protocols.
Does crash risk increase when emergency vehicles are driving with lights and sirens?
Missikpode, Celestin; Peek-Asa, Corinne; Young, Tracy; Hamann, Cara
2018-04-01
Emergency vehicles, such as police, ambulances, and fire vehicles, need to arrive at the scene of emergencies as quickly as possible, and thus they often travel in emergency mode - using their lights and sirens and often bypassing traffic signals. We examined whether travelling in emergency mode increased crash risk among police, ambulance and fire vehicles. We conducted a quasi-induced exposure analysis using data from the Iowa Crash Database for the period of 2005 through 2013. The data are maintained by the Iowa Department of Transportation (IADOT), Office of Driver Services (ODS) and includes all investigating police officer's reports of motor vehicle crashes. The quasi-induced exposure method is an approach to calculate crash risk in the absence of exposure data using vehicles without a contributing cause (did not contribute to the crash) as a proxy for the baseline driving population. From 2005 - 2013, police vehicles were involved in 2406 crashes and ambulances and fire vehicles were involved in 528 crashes. Police vehicles were 1.8 times more likely to crash while driving in emergency mode than usual mode; this was a statistically significant increase. Ambulance and fire vehicles were not more likely to crash in emergency mode compared with usual mode. For police, other factors that contributed to crash risk included gender, age, icy/snowy roads, unpaved roads, and intersections. For ambulances and fire vehicles, other factors that contributed to crash risk included gender, age, weekends, icy/snowy roads and urban locations. Crash risk increased when police vehicles drove with lights and sirens but did not increase for ambulance and fire vehicles. Further research is necessary to develop and evaluate strategies to mitigate crash risk among police vehicles. Cultural approaches which prioritize transportation safety in conjunction with reaching the scene as quickly as possible may be warranted. Copyright © 2018 Elsevier Ltd. All rights reserved.
Gasoline prices and traffic crashes in Alabama, 1999-2009.
Chi, Guangqing; McClure, Timothy E; Brown, David B
2012-09-01
The price of gasoline has been found to be negatively associated with traffic crashes in a limited number of studies. However, most of the studies have focused either on fatal crashes only or on all crashes but measured over a very short time period. In this study, we examine gasoline price effects on all traffic crashes by demographic groups in the state of Alabama from 1999 to 2009. Using negative binomial regression techniques to examine monthly data from 1999 to 2009 in the state of Alabama, we estimate the effects of changes in gasoline price on changes in automobile crashes. We also examine how these effects differ by age group (16-20, 21-25, 26-30, 31-64, and 65+), gender (male and female), and race/ethnicity (non-Hispanic white, non-Hispanic black, and Hispanic). The results show that gasoline prices have both short-term and long-term effects on reducing total traffic crashes and crashes of each age, gender, and race/ethnicity group (except Hispanic due to data limitations). The short-term and long-term effects are not statistically different for each individual demographic group. Gasoline prices have a stronger effect in reducing crashes involving drivers aged 16 to 20 than crashes involving drivers aged 31 to 64 and 65+ in the short term; the effects, however, are not statistically different across other demographic groups. Although gasoline price increases are not favored, our findings show that gasoline price increases (or decreases) are associated with reductions (or increases) in the incidence of traffic crashes. If gasoline prices had remained at the 1999 level of $1.41 from 1999 to 2009, applying the estimated elasticities would result in a predicted increase in total crashes of 169,492 (or 11.3%) from the actual number of crashes. If decision makers wish to reduce traffic crashes, increasing gasoline taxes is a possible option-however, doing so would increase travel costs and lead to equity concerns. These findings may help to shape transportation safety planning and policy making.
Vehicle crashworthiness ratings in Australia.
Cameron, M; Mach, T; Neiger, D; Graham, A; Ramsay, R; Pappas, M; Haley, J
1994-08-01
The paper reviews the published vehicle safety ratings based on mass crash data from the United States, Sweden, and Great Britain. It then describes the development of vehicle crashworthiness ratings based on injury compensation claims and police accident reports from Victoria and New South Wales, the two most populous states in Australia. Crashworthiness was measured by a combination of injury severity (of injured drivers) and injury risk (of drivers involved in crashes). Injury severity was based on 22,600 drivers injured in crashes in the two states. Injury risk was based on 70,900 drivers in New South Wales involved in crashes after which a vehicle was towed away. Injury risk measured in this way was compared with the "relative injury risk" of particular model cars involved in two car crashes in Victoria (where essentially only casualty crashes are reported), which was based on the method developed by Folksam Insurance in Sweden from Evans' double-pair comparison method. The results include crashworthiness ratings for the makes and models crashing in Australia in sufficient numbers to measure their crash performance adequately. The ratings were normalised for the driver sex and speed limit at the crash location, the two factors found to be strongly related to injury risk and/or severity and to vary substantially across makes and models of Australian crash-involved cars. This allows differences in crashworthiness of individual models to be seen, uncontaminated by major crash exposure differences.
Is the useful field of view a good predictor of at-fault crash risk in elderly Japanese drivers?
Sakai, Hiroyuki; Uchiyama, Yuji; Takahara, Miwa; Doi, Shun'ichi; Kubota, Fumiko; Yoshimura, Takayoshi; Tachibana, Atsumichi; Kurahashi, Tetsuo
2015-05-01
Although age-related decline in the useful field of view (UFOV) is well recognized as a risk factor for at-fault crash involvement in elderly drivers, there is still room to study its applicability to elderly Japanese drivers. In the current study, we thus examined the relationship between UFOV and at-fault crash history in an elderly Japanese population. We also explored whether potential factors that create awareness of reduced driving fitness could be a trigger for the self-regulation of driving in elderly drivers. We measured UFOV and at-fault crash history from 151 community-dwelling Japanese aged 60 years or older, and compared UFOV of at-fault crash-free and crash-involved drivers. We also measured self-evaluated driving style using a questionnaire. UFOV in crash-involved drivers was significantly lower than that in crash-free drivers. No significant difference was found in self-evaluated driving style between crash-free and crash-involved drivers. In addition, there was no significant association between UFOV and self-evaluated driving style. The present study showed that UFOV is a good predictor of at-fault crash risk in elderly Japanese drivers. Furthermore, our data imply that it might be difficult for elderly drivers to adopt appropriate driving strategies commensurate with their current driving competence. © 2014 Japan Geriatrics Society.
Multivariate spatial models of excess crash frequency at area level: case of Costa Rica.
Aguero-Valverde, Jonathan
2013-10-01
Recently, areal models of crash frequency have being used in the analysis of various area-wide factors affecting road crashes. On the other hand, disease mapping methods are commonly used in epidemiology to assess the relative risk of the population at different spatial units. A natural next step is to combine these two approaches to estimate the excess crash frequency at area level as a measure of absolute crash risk. Furthermore, multivariate spatial models of crash severity are explored in order to account for both frequency and severity of crashes and control for the spatial correlation frequently found in crash data. This paper aims to extent the concept of safety performance functions to be used in areal models of crash frequency. A multivariate spatial model is used for that purpose and compared to its univariate counterpart. Full Bayes hierarchical approach is used to estimate the models of crash frequency at canton level for Costa Rica. An intrinsic multivariate conditional autoregressive model is used for modeling spatial random effects. The results show that the multivariate spatial model performs better than its univariate counterpart in terms of the penalized goodness-of-fit measure Deviance Information Criteria. Additionally, the effects of the spatial smoothing due to the multivariate spatial random effects are evident in the estimation of excess equivalent property damage only crashes. Copyright © 2013 Elsevier Ltd. All rights reserved.
Truck crash severity in New York city: An investigation of the spatial and the time of day effects.
Zou, Wei; Wang, Xiaokun; Zhang, Dapeng
2017-02-01
This paper investigates the differences between single-vehicle and multi-vehicle truck crashes in New York City. The random parameter models take into account the time of day effect, the heterogeneous truck weight effect and other influencing factors such as crash characteristics, driver and vehicle characteristics, built environment factors and traffic volume attributes. Based on the results from the co-location quotient analysis, a spatial generalized ordered probit model is further developed to investigate the potential spatial dependency among single-vehicle truck crashes. The sample is drawn from the state maintained incident data, the publicly available Smart Location Data, and the BEST Practices Model (BPM) data from 2008 to 2012. The result shows that there exists a substantial difference between factors influencing single-vehicle and multi-vehicle truck crash severity. It also suggests that heterogeneity does exist in the truck weight, and it behaves differently in single-vehicle and multi-vehicle truck crashes. Furthermore, individual truck crashes are proved to be spatially dependent events for both single and multi-vehicle crashes. Last but not least, significant time of day effects were found for PM and night time slots, crashes that occurred in the afternoons and at nights were less severe in single-vehicle crashes, but more severe in multi-vehicle crashes. Copyright © 2016. Published by Elsevier Ltd.
2010 South Dakota motor vehicle traffic crash summary
DOT National Transportation Integrated Search
2011-01-01
The Motor Vehicle Traffic Crash Summary is divided into two main sections, Historical Trends and 2010 Motor Vehicle Traffic Crash Profile. The Historical Trend section provides information on alcohol involvement in motor vehicle crashes, severity of ...
2007 Oregon state highway accident rate tables
DOT National Transportation Integrated Search
2008-09-01
State highway crash rate tables present crash frequencies in relation to traffic volume and : highway mileage. The four major sections of this publication are: : I Results of Analysis : II State Highway Crash Rates : III Fatal Traffic Crash Summaries...
2009 Oregon state highway accident rate tables
DOT National Transportation Integrated Search
2010-08-01
State highway crash rate tables present crash frequencies in relation to traffic volume and : highway mileage. The four major sections of this publication are: : I Results of Analysis : II State Highway Crash Rates : III Fatal Traffic Crash Summaries...
Illinois crash facts and statistics, 2002
DOT National Transportation Integrated Search
2002-01-01
This publication, Illinois Traffic Crash Facts : and Statistics for 2002, is designed to provide an : overview of motor vehicle crash experience in : Illinois. In addition to a plethora of crash data, the : publication includes key events in th...
Illinois crash facts and statistics, 2004-2005
DOT National Transportation Integrated Search
2005-01-01
The 2004-2005 Illinois Crash Facts & Statistics publication : is designed to provide the public with an overview of motor : vehicle crashes that occur in Illinois. This publication not : only consists of crash data but includes information abou...
Illinois crash facts and statistics, 2001
DOT National Transportation Integrated Search
2001-01-01
This publication, Illinois Traffic Crash Facts : and Statistics for 2001, is designed to provide an : overview of motor vehicle crash experience in : Illinois. In addition to a plethora of crash data, the : publication includes key events in th...
Illinois crash facts and statistics, 2003
DOT National Transportation Integrated Search
2003-01-01
This publication, Illinois Traffic Crash Facts : and Statistics for 2003, is designed to provide an : overview of motor vehicle crash experience in : Illinois. In addition to a plethora of crash data, the : publication includes key events in th...
2004 Oregon state highway accident rate tables
DOT National Transportation Integrated Search
2005-08-01
State highway crash rate tables present crash frequencies in relation to traffic volume and : highway mileage. The four major sections of this publication are: : I Results of Analysis : II State Highway Crash Rates : III Fatal Traffic Crash Summaries...
2008 Oregon state highway accident rate tables
DOT National Transportation Integrated Search
2009-08-01
State highway crash rate tables present crash frequencies in relation to traffic volume and : highway mileage. The four major sections of this publication are: : I Results of Analysis : II State Highway Crash Rates : III Fatal Traffic Crash Summaries...
2006 Oregon state highway accident rate tables
DOT National Transportation Integrated Search
2007-07-01
State highway crash rate tables present crash frequencies in relation to traffic volume and : highway mileage. The four major sections of this publication are: : I Results of Analysis : II State Highway Crash Rates : III Fatal Traffic Crash Summaries...
2010 Oregon state highway accident rate tables
DOT National Transportation Integrated Search
2011-11-01
State highway crash rate tables present crash frequencies in relation to traffic volume and : highway mileage. The four major sections of this publication are: I. Results of Analysis, II. State Highway Crash Rates, III. Fatal Traffic Crash Summaries,...
Large truck and bus crash facts, 2010.
DOT National Transportation Integrated Search
2012-09-01
This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and : property damage only crashes involving large trucks and buses in 2010. Selected crash statistics on passenger : vehicles are also presen...
Large truck and bus crash facts, 2007.
DOT National Transportation Integrated Search
2009-03-01
This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and : property damage only crashes involving large trucks and buses in 2007. Selected crash statistics on passenger : vehicles are also presen...
Large truck and bus crash facts, 2008.
DOT National Transportation Integrated Search
2010-03-01
This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and : property damage only crashes involving large trucks and buses in 2008. Selected crash statistics on passenger : vehicles are also presen...
Large truck and bus crash facts, 2011.
DOT National Transportation Integrated Search
2013-10-01
This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and : property damage only crashes involving large trucks and buses in 2011. Selected crash statistics on passenger : vehicles are also presen...
Large truck and bus crash facts, 2013.
DOT National Transportation Integrated Search
2015-04-01
This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and property damage only crashes involving large trucks and buses in 2013. Selected crash statistics on passenger vehicles are also presented ...
Large truck and bus crash facts, 2009.
DOT National Transportation Integrated Search
2011-10-01
This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and : property damage only crashes involving large trucks and buses in 2009. Selected crash statistics on passenger : vehicles are also presen...
Large truck and bus crash facts, 2012.
DOT National Transportation Integrated Search
2014-06-01
This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and property damage only crashes involving large trucks and buses in 2012. Selected crash statistics on passenger vehicles are also presented ...
Computer simulations and experimental study on crash box of automobile in low speed collision
NASA Astrophysics Data System (ADS)
Liu, Yanjie; Ding, Lin; Yan, Shengyuan; Yang, Yongsheng
2008-11-01
Based on the problems of energy-absorbing components in the automobile low speed collision process, according to crash box frontal crash test in low speed as the example, the simulation analysis of crash box impact process was carried out by Hyper Mesh and LS-DYNA. Each parameter on the influence modeling was analyzed by mathematics analytical solution and test comparison, which guaranteed that the model was accurate. Combination of experiment and simulation result had determined the weakness part of crash box structure crashworthiness aspect, and improvement method of crash box crashworthiness was discussed. Through numerical simulation of the impact process of automobile crash box, the obtained analysis result was used to optimize the design of crash box. It was helpful to improve the vehicles structure and decrease the collision accident loss at most. And it was also provided a useful method for the further research on the automobile collision.
Storvik, Steven G; Campbell, Julius Q; Wheeler, Jeffrey B
2017-06-01
Rates of death because of asphyxia in motor vehicle crashes have been previously estimated using county and statewide data sets, but national estimates have not been reported. The literature regarding asphyxia in motor vehicle crashes primarily involves discussions about clinical findings, and crash-related variables have been sparsely reported. The current study calculated a nationwide fatality rate for asphyxia in motor vehicle crashes of 1.4%. Seventeen case studies of asphyxia were also reported providing crash-, vehicle-, and occupant-related variables. These included type of accident, crash severity, seat belt use, containment status, extent of occupant compartment intrusion, height, weight, and injury pattern. The data presented can be used to better understand the injury mechanism, identify risk factors, develop possible protective countermeasures, and create situational awareness for emergency responders and investigators.
The mean time-limited crash rate of stock price
NASA Astrophysics Data System (ADS)
Li, Yun-Xian; Li, Jiang-Cheng; Yang, Ai-Jun; Tang, Nian-Sheng
2017-05-01
In this article we investigate the occurrence of stock market crash in an economy cycle. Bayesian approach, Heston model and statistical-physical method are considered. Specifically, Heston model and an effective potential are employed to address the dynamic changes of stock price. Bayesian approach has been utilized to estimate the Heston model's unknown parameters. Statistical physical method is used to investigate the occurrence of stock market crash by calculating the mean time-limited crash rate. The real financial data from the Shanghai Composite Index is analyzed with the proposed methods. The mean time-limited crash rate of stock price is used to describe the occurrence of stock market crash in an economy cycle. The monotonous and nonmonotonous behaviors are observed in the behavior of the mean time-limited crash rate versus volatility of stock for various cross correlation coefficient between volatility and price. Also a minimum occurrence of stock market crash matching an optimal volatility is discovered.
Sleep deficiency and motor vehicle crash risk in the general population: a prospective cohort study.
Gottlieb, Daniel J; Ellenbogen, Jeffrey M; Bianchi, Matt T; Czeisler, Charles A
2018-03-20
Insufficient sleep duration and obstructive sleep apnea, two common causes of sleep deficiency in adults, can result in excessive sleepiness, a well-recognized cause of motor vehicle crashes, although their contribution to crash risk in the general population remains uncertain. The objective of this study was to evaluate the relation of sleep apnea, sleep duration, and excessive sleepiness to crash risk in a community-dwelling population. This was a prospective observational cohort study nested within the Sleep Heart Health Study, a community-based study of the health consequences of sleep apnea. The participants were 1745 men and 1456 women aged 40-89 years. Sleep apnea was measured by home polysomnography and questionnaires were used to assess usual sleep duration and daytime sleepiness. A follow-up questionnaire 2 years after baseline ascertained driving habits and motor vehicle crash history. Logistic regression analysis was used to examine the relation of sleep apnea and sleep duration at baseline to the occurrence of motor vehicle crashes during the year preceding the follow-up visit, adjusting for relevant covariates. The population-attributable fraction of motor vehicle crashes was estimated from the sample proportion of motor vehicle crashes and the adjusted odds ratios for motor vehicle crash within each exposure category. Among 3201 evaluable participants, 222 (6.9%) reported at least one motor vehicle crash during the prior year. A higher apnea-hypopnea index (p < 0.01), fewer hours of sleep (p = 0.04), and self-reported excessive sleepiness (p < 0.01) were each significantly associated with crash risk. Severe sleep apnea was associated with a 123% increased crash risk, compared to no sleep apnea. Sleeping 6 hours per night was associated with a 33% increased crash risk, compared to sleeping 7 or 8 hours per night. These associations were present even in those who did not report excessive sleepiness. The population-attributable fraction of motor vehicle crashes was 10% due to sleep apnea and 9% due to sleep duration less than 7 hours. Sleep deficiency due to either sleep apnea or insufficient sleep duration is strongly associated with motor vehicle crashes in the general population, independent of self-reported excessive sleepiness.
Sleep-deprived young drivers and the risk for crash: the DRIVE prospective cohort study.
Martiniuk, Alexandra L C; Senserrick, Teresa; Lo, Serigne; Williamson, Ann; Du, Wei; Grunstein, Ronald R; Woodward, Mark; Glozier, Nick; Stevenson, Mark; Norton, Robyn; Ivers, Rebecca Q
2013-07-01
Short sleep duration is common in adolescents and young adults, and short sleep duration is a risk factor for motor vehicle crash. To assess the association between hours of sleep and the risk for motor vehicle crash, including the time of day of crash and types of crash (single, multiple vehicle, run off road, and intersection). Prospective cohort study. New South Wales, Australia. Questionnaire responses were obtained from 20,822 newly licensed drivers aged 17 to 24 years. Participants held a first-stage provisional license between June 2003 and December 2004 prospectively linked to licensing and police-reported crash data, with an average of 2 years of follow-up. Analyses were conducted on a subsample of 19,327 participants for which there was full information. Sleeping 6 or fewer hours per night. The main outcome variable was police-reported crash. Multivariable Poisson regression models were used to investigate the role of sleep duration on the risk for crash. On average, those who reported sleeping 6 or fewer hours per night had an increased risk for crash compared with those who reported sleeping more than 6 hours (relative risk [RR], 1.21; 95% CI, 1.04-1.41). Less weekend sleep was significantly associated with an increased risk for run-off-road crashes (RR, 1.55; 95% CI, 1.21-2.00). Crashes for individuals who had less sleep per night (on average and on weekends) were significantly more likely to occur between 8 pm and 6 am (RR, 1.86; 95% CI, 1.11-3.13, for midnight to 5:59 am and RR, 1.66; 95% CI, 1.15-2.39, for 8:00 pm to 11:59 pm). Less sleep per night significantly increased the risk for crash for young drivers. Less sleep on weekend nights increased the risk for run-off-road crashes and crashes occurring in the late-night hours. This provides rationale for governments and health care providers to address sleep-related crashes among young drivers.
Sasidharan, Lekshmi; Donnell, Eric T
2014-10-01
Accurate estimation of the expected number of crashes at different severity levels for entities with and without countermeasures plays a vital role in selecting countermeasures in the framework of the safety management process. The current practice is to use the American Association of State Highway and Transportation Officials' Highway Safety Manual crash prediction algorithms, which combine safety performance functions and crash modification factors, to estimate the effects of safety countermeasures on different highway and street facility types. Many of these crash prediction algorithms are based solely on crash frequency, or assume that severity outcomes are unchanged when planning for, or implementing, safety countermeasures. Failing to account for the uncertainty associated with crash severity outcomes, and assuming crash severity distributions remain unchanged in safety performance evaluations, limits the utility of the Highway Safety Manual crash prediction algorithms in assessing the effect of safety countermeasures on crash severity. This study demonstrates the application of a propensity scores-potential outcomes framework to estimate the probability distribution for the occurrence of different crash severity levels by accounting for the uncertainties associated with them. The probability of fatal and severe injury crash occurrence at lighted and unlighted intersections is estimated in this paper using data from Minnesota. The results show that the expected probability of occurrence of fatal and severe injury crashes at a lighted intersection was 1 in 35 crashes and the estimated risk ratio indicates that the respective probabilities at an unlighted intersection was 1.14 times higher compared to lighted intersections. The results from the potential outcomes-propensity scores framework are compared to results obtained from traditional binary logit models, without application of propensity scores matching. Traditional binary logit analysis suggests that the probability of occurrence of severe injury crashes is higher at lighted intersections compared to unlighted intersections, which contradicts the findings obtained from the propensity scores-potential outcomes framework. This finding underscores the importance of having comparable treated and untreated entities in traffic safety countermeasure evaluations. Copyright © 2014 Elsevier Ltd. All rights reserved.
Hosseinpour, Mehdi; Sahebi, Sina; Zamzuri, Zamira Hasanah; Yahaya, Ahmad Shukri; Ismail, Noriszura
2018-06-01
According to crash configuration and pre-crash conditions, traffic crashes are classified into different collision types. Based on the literature, multi-vehicle crashes, such as head-on, rear-end, and angle crashes, are more frequent than single-vehicle crashes, and most often result in serious consequences. From a methodological point of view, the majority of prior studies focused on multivehicle collisions have employed univariate count models to estimate crash counts separately by collision type. However, univariate models fail to account for correlations which may exist between different collision types. Among others, multivariate Poisson lognormal (MVPLN) model with spatial correlation is a promising multivariate specification because it not only allows for unobserved heterogeneity (extra-Poisson variation) and dependencies between collision types, but also spatial correlation between adjacent sites. However, the MVPLN spatial model has rarely been applied in previous research for simultaneously modelling crash counts by collision type. Therefore, this study aims at utilizing a MVPLN spatial model to estimate crash counts for four different multi-vehicle collision types, including head-on, rear-end, angle, and sideswipe collisions. To investigate the performance of the MVPLN spatial model, a two-stage model and a univariate Poisson lognormal model (UNPLN) spatial model were also developed in this study. Detailed information on roadway characteristics, traffic volume, and crash history were collected on 407 homogeneous segments from Malaysian federal roads. The results indicate that the MVPLN spatial model outperforms the other comparing models in terms of goodness-of-fit measures. The results also show that the inclusion of spatial heterogeneity in the multivariate model significantly improves the model fit, as indicated by the Deviance Information Criterion (DIC). The correlation between crash types is high and positive, implying that the occurrence of a specific collision type is highly associated with the occurrence of other crash types on the same road segment. These results support the utilization of the MVPLN spatial model when predicting crash counts by collision manner. In terms of contributing factors, the results show that distinct crash types are attributed to different subsets of explanatory variables. Copyright © 2018 Elsevier Ltd. All rights reserved.
Optimization of a simplified automobile finite element model using time varying injury metrics.
Gaewsky, James P; Danelson, Kerry A; Weaver, Caitlin M; Stitzel, Joel D
2014-01-01
In 2011, frontal crashes resulted in 55% of passenger car injuries with 10,277 fatalities and 866,000 injuries in the United States. To better understand frontal crash injury mechanisms, human body finite element models (FEMs) can be used to reconstruct Crash Injury Research and Engineering Network (CIREN) cases. A limitation of this method is the paucity of vehicle FEMs; therefore, we developed a functionally equivalent simplified vehicle model. The New Car Assessment Program (NCAP) data for our selected vehicle was from a frontal collision with Hybrid III (H3) Anthropomorphic Test Device (ATD) occupant. From NCAP test reports, the vehicle geometry was created and the H3 ATD was positioned. The material and component properties optimized using a variation study process were: steering column shear bolt fracture force and stroke resistance, seatbelt pretensioner force, frontal and knee bolster airbag stiffness, and belt friction through the D-ring. These parameters were varied using three successive Latin Hypercube Designs of Experiments with 130-200 simulations each. The H3 injury response was compared to the reported NCAP frontal test results for the head, chest and pelvis accelerations, and seat belt and femur forces. The phase, magnitude, and comprehensive error factors, from a Sprague and Geers analysis were calculated for each injury metric and then combined to determine the simulations with the best match to the crash test. The Sprague and Geers analyses typically yield error factors ranging from 0 to 1 with lower scores being more optimized. The total body injury response error factor for the most optimized simulation from each round of the variation study decreased from 0.466 to 0.395 to 0.360. This procedure to optimize vehicle FEMs is a valuable tool to conduct future CIREN case reconstructions in a variety of vehicles.
Planar Impacts in Rollover Crashes: Significance, Distribution and Injury Epidemiology
Bose, Dipan; Kerrigan, Jason R.; Foster, Jonathan B.; Crandall, Jeff R.; Tobaru, Shigeo
2011-01-01
While one third of all fatal motor vehicle crashes involve rollover of the vehicle, a substantially large portion of these rollover crashes involve planar impacts (e.g., frontal, side or rear impact) that influence the crash kinematics and subsequently the injury outcome. The objective of the study was to evaluate the distribution of planar impacts in rollover crashes, and in particular, to describe the differences in the underlying crash kinematics, injury severity and the regional distribution of injuries when compared to the rollover-dominated crashes without significant planar impact (i.e., primary rollovers). Sampled cases (n=6,900) from the U.S. National Automotive Sampling System – Crashworthiness Data System, representing approximately 3.3 million belted drivers involved in a rollover crash in years 1998–2008, were analyzed. Single vehicle rollover crashes with significant planar impact (21% of all rollover crashes) were in general more likely to result in occupant fatality and involved higher incidence of moderate to severe injuries compared to single vehicle primary rollovers (p<0.05). A substantial proportion of the planar impact rollovers ended in single quarter turn crashes (30%), mostly resulting from a frontal impact (59%). While chest was the most frequently injured body region among all rollover victims sustaining severe injuries, severe injuries sustained in primary rollovers were more isolated (single body region) in comparison to the ones sustained in rollovers with planar impacts. The results emphasize the higher risk of rollover victims sustaining an injury and the differences in distribution of injuries sustained when a planar impact is associated with the rollover crash. PMID:22105400
McDonald, Catherine C.; Seacrist, Thomas S.; Lee, Yi-Ching; Loeb, Helen; Kandadai, Venk; Winston, Flaura K.
2014-01-01
Summary Driving simulators can be used to evaluate driving performance under controlled, safe conditions. Teen drivers are at particular risk for motor vehicle crashes and simulated driving can provide important information on performance. We developed a new simulator protocol, the Simulated Driving Assessment (SDA), with the goal of providing a new tool for driver assessment and a common outcome measure for evaluation of training programs. As an initial effort to examine the validity of the SDA to differentiate performance according to experience, this analysis compared driving behaviors and crashes between novice teens (n=20) and experienced adults (n=17) on a high fidelity simulator for one common crash scenario, a rear-end crash. We examined headway time and crashes during a lead truck with sudden braking event in our SDA. We found that 35% of the novice teens crashed and none of the experienced adults crashed in this lead truck braking event; 50% of the teens versus 25% of the adults had a headway time <3 seconds at the time of truck braking. Among the 10 teens with <3 seconds headway time, 70% crashed. Among all participants with a headway time of 2–3 seconds, further investigation revealed descriptive differences in throttle position and brake pedal force when comparing teens who crashed, teens who did not crash and adults (none of whom crashed). Even with a relatively small sample, we found statistically significant differences in headway time for adults and teens, providing preliminary construct validation for our new SDA. PMID:25197724
Huisingh, Carrie; Levitan, Emily B.; Irvin, Marguerite R.; MacLennan, Paul; Wadley, Virginia; Owsley, Cynthia
2017-01-01
Purpose An innovative methodology using naturalistic driving data was used to examine the association between visual sensory and visual-cognitive function and rates of future crash or near-crash involvement among older drivers. Methods The Strategic Highway Research Program (SHRP2) Naturalistic Driving Study was used for this prospective analysis. The sample consisted of N = 659 drivers aged ≥70 years and study participation lasted 1 or 2 years for most participants. Distance and near visual acuity, contrast sensitivity, peripheral vision, visual processing speed, and visuospatial skills were assessed at baseline. Crash and near-crash involvement were based on video recordings and vehicle sensors. Poisson regression models were used to generate crude and adjusted rate ratios (RRs) and 95% confidence intervals, while accounting for person-miles of travel. Results After adjustment, severe impairment of the useful field of view (RR = 1.33) was associated with an increased rate of near-crash involvement. Crash, severe crash, and at-fault crash involvement were associated with impaired contrast sensitivity in the worse eye (RRs = 1.38, 1.54, and 1.44, respectively) and far peripheral field loss in both eyes (RRs = 1.74, 2.32, and 1.73, respectively). Conclusions Naturalistic driving data suggest that contrast sensitivity in the worse eye and far peripheral field loss in both eyes elevate the rates of crash involvement, and impaired visual processing speed elevates rates of near-crash involvement among older drivers. Naturalistic driving data may ultimately be critical for understanding the relationship between vision and driving safety. PMID:28605807
Ferguson, Susan A
2007-12-01
Electronic stability control (ESC) is designed to help drivers maintain heading control of their vehicles in high-speed or sudden maneuvers and on slippery roads. The wider proliferation of ESC across the vehicle fleet has allowed evaluation of its effects in real-world crashes in many countries, including Japan, Germany, Sweden, France, Great Britain, and the United States. This article provides a summary of the findings. Studies that examined the real-world effectiveness of ESC were reviewed. Crash effects have been examined for different roadways, using differing analytic methods, different crash severities, and different make/model vehicles including both cars and SUVs. The review discusses the methodological differences and examines the findings according to vehicle type, crash type and severity, and road conditions. The overwhelming majority of studies find that ESC is highly effective in reducing single-vehicle crashes in cars and SUVs. Fatal single-vehicle crashes involving cars are reduced by about 30-50% and SUVs by 50-70%. Fatal rollover crashes are estimated to be about 70-90% lower with ESC regardless of vehicle type. A number of studies find improved effectiveness in reducing crashes when road conditions are slippery. There is little or no effect of ESC in all multi-vehicle crashes; however, there is a 17-38% reduction in more serious, fatal multi-vehicle crashes. Given the extraordinary benefits of ESC in preventing crashes, especially those with more serious outcomes, the implementation of ESC should be accelerated to cover the full range of passenger vehicles in both developed and developing markets.
Increased inequality in mortality from road crashes among Arabs and Jews in Israel.
Magid, Avi; Leibovitch-Zur, Shalhevet; Baron-Epel, Orna
2015-01-01
Previous studies in several countries have shown that the economically disadvantaged seem to have a greater risk of being involved in a car crash. The aim of the present study was to compare rates and trends in mortality and injury from road crashes by age among the Arab and Jewish populations in Israel. Data on road crashes with casualties (2003-2011) from the Israeli Central Bureau of Statistics were analyzed. Age-adjusted road crash injury rates and mortality rates for 2003 to 2011 were calculated and time trends for each age group and population group are presented. Time trend significance was evaluated by linear regression models. Arabs in Israel are at increased risk of injury and mortality from road crashes compared to Jews. Road crash injury rates have significantly decreased in both populations over the last decade, although the rates have been persistently higher among Arabs. Road crash mortality rates have also decreased significantly in the Jewish population but not in the Arab population. This implies an increase in the disparity in mortality between Jews and Arabs. The most prominent differences in road crash injury and mortality rates between Arabs and Jews can be observed in young adults and young children. The reduction in road crashes in the last decade is a positive achievement. However, the reductions are not equal among Arabs and Jews in Israel. Therefore, an increase in the disparities in mortality from road crashes is apparent. Public health efforts need to focus specifically on decreasing road crashes in the Arab community.
Crash Rates of Quebec Drivers with Medical Conditions
Dow, Jamie; Gaudet, Michel; Turmel, Émilie
2013-01-01
Using a databank that combines comprehensive medical data with the driving records of 96% of the drivers in Quebec, odds ratios were calculated for crash risk involving death or serious injury according to the diagnosis of medical conditions traditionally associated with increased crash risk. Results were controlled for age, sex, residence (rural/urban), possession of a professional licence (classes 1 – 4), previous involvement in a crash with injury or death and for the presence of other medical conditions. In addition, crash risk was calculated for drivers with multiple conditions. There was a slight to moderate increase in crash risk for most of the conditions and an incremental increase in crash risk as the number of conditions increased. PMID:24406946
Cable median barrier failure analysis and prevention.
DOT National Transportation Integrated Search
2012-12-01
Cross-median crashes have been identified as one of the highest injury or fatality risk crash types. Although crossmedian : crashes account for only 2% to 5% of all median crash events, they are disproportionately represented in the number : and freq...
A comprehensive engineering analysis of motorcycle crashes in Maryland.
DOT National Transportation Integrated Search
2010-12-01
The goal of this study was to identify recurring or common road characteristics of motorcycle crashes : in Maryland from 1998 to 2007. Motorcycle crash data was obtained from the National Highway : Traffic Safety Administrations Crash Outcome Data...
1997 New Mexico traffic crash information
DOT National Transportation Integrated Search
1998-06-01
This edition of New Mexico Traffic Crash Information reviews : traffic crash data in New Mexico from January through : December, 1997. It presents crash data in the form of graphs : for those who prefer an impressionistic view and tables for : those ...
1995 New Mexico traffic crash information
DOT National Transportation Integrated Search
1996-09-01
This edition of New Mexico Traffic Crash Information reviews : traffic crash data in New Mexico from January through : December, 1995. It presents crash data in the form of graphs : for those who prefer an impressionistic view and tables for : those ...
Frequency of target crashes for IntelliDrive safety systems
DOT National Transportation Integrated Search
2010-10-01
This report estimates the frequency of different crash types that would potentially be addressed by various categories of Intelligent Transportation Systems as part of the IntelliDriveSM safety systems program. Crash types include light-vehicle crash...
Commercial bus crashes in North Carolina 1995-1999
DOT National Transportation Integrated Search
2000-04-01
Tables and figures are shown to depict a statistical representation of commercial bus crashes in North Carolina. Information displayed includes crash frequency, crashes by county, accident severity, time of day, month of the year, class of roadway, r...
Problem definition for pre-crash sensing advanced restraints.
DOT National Transportation Integrated Search
2009-04-01
This report presents the results of crash analyses that defined and prioritized target crashes for advanced restraint systems based on pre-crash sensors. These analyses targeted the driver and front-seat passenger 13 or older, traveling in light vehi...
Developing inexpensive crash countermeasures for Louisiana local roads.
DOT National Transportation Integrated Search
2014-03-01
Although 40% of all crashes in Louisiana are on local roads, local road safety improvement programs have not received : the attention needed to reduce crashes. Local road crash countermeasures are an important part of the overall efforts to : reduce ...
2000 New Mexico traffic crash information
DOT National Transportation Integrated Search
2002-03-01
This edition of New Mexico Traffic Crash Information reviews traffic : crash data in New Mexico from January through December, 2000. : It presents crash data in the form of graphs for those who prefer : an impressionistic view and tables for those wh...
2005 New Mexico traffic crash information
DOT National Transportation Integrated Search
2006-11-01
This edition of New Mexico Traffic Crash Information reviews traffic : crash data in New Mexico from January through December, 2005. : It presents crash data in the form of graphs for those who prefer : an impressionistic view and tables for those wh...
2001 New Mexico traffic crash information
DOT National Transportation Integrated Search
2003-01-01
This edition of New Mexico Traffic Crash Information reviews traffic : crash data in New Mexico from January through December, 2001. : It presents crash data in the form of graphs for those who prefer : an impressionistic view and tables for those wh...
2008 New Mexico traffic crash information
DOT National Transportation Integrated Search
2010-05-01
This edition of New Mexico Traffic Crash Information reviews : traffic crash data in New Mexico from January through December, : 2008. It presents crash data in the form of graphs for those who : prefer an impressionistic view and tables for those wh...
1996 New Mexico traffic crash information
DOT National Transportation Integrated Search
1997-06-01
This edition of New Mexico Traffic Crash Information reviews : traffic crash data in New Mexico from January through : December, 1997. It presents crash data in the form of graphs : for those who prefer an impressionistic view and tables for : those ...
1998 New Mexico traffic crash information
DOT National Transportation Integrated Search
1999-06-01
This edition of New Mexico Traffic Crash Information reviews : traffic crash data in New Mexico from January through : December, 1998. It presents crash data in the form of graphs : for those who prefer an impressionistic view and tables for : those ...
2002 New Mexico traffic crash information
DOT National Transportation Integrated Search
2004-02-01
This edition of New Mexico Traffic Crash Information reviews traffic : crash data in New Mexico from January through December, 2002. : It presents crash data in the form of graphs for those who prefer : an impressionistic view and tables for those wh...
2004 Wisconsin traffic crash facts
DOT National Transportation Integrated Search
2005-07-01
2004 Facts and Figures - 784 persons were killed in Wisconsin motor vehicle traffic crashes. This is an average of two lives lost each day on Wisconsin trafficways. - 55,258 persons were injured in 38,451 reported injury crashes and 714 fatal crashes...
2004 South Dakota motor vehicle traffic crash summary
DOT National Transportation Integrated Search
2005-01-01
The South Dakota Motor Vehicle Traffic Crash Summary was developed to provide an overview of : the South Dakota traffic crash picture, as well as make frequently requested information available. : Beginning in 2004, South Dakota developed its Crash D...
2005 Oregon state highway accident rate tables
DOT National Transportation Integrated Search
2006-08-01
State highway crash rate tables present crash frequencies in relation to traffic volume and highway mileage. The four major sections of this publication are: I Results of Analysis II State Highway Crash Rates III Fatal Traffic Crash Summaries IV Appe...
2005 South Dakota motor vehicle traffic crash summary
DOT National Transportation Integrated Search
2006-05-01
The South Dakota Motor Vehicle Traffic Crash Summary was developed to provide an overview of : the South Dakota traffic crash picture, as well as make frequently requested information available. : Beginning in 2004, South Dakota developed its Crash D...
Socio-economic analysis of fatal crash trends : final report.
DOT National Transportation Integrated Search
2005-12-01
This report describes the analysis of fatal crash patterns and explores the impact of socioeconomic factors and safety regulations on statewide crash rates. This analysis separated statewide crash rates between 2002 and 2004 into two samples, 1) thos...
Savino, Giovanni; Rizzi, Matteo; Brown, Julie; Piantini, Simone; Meredith, Lauren; Albanese, Bianca; Pierini, Marco; Fitzharris, Michael
2014-01-01
In 2006, Motorcycle Autonomous Emergency Braking (MAEB) was developed by a European Consortium (Powered Two Wheeler Integrated Safety, PISa) as a crash severity countermeasure for riders. This system can detect an obstacle through sensors in the front of the motorcycle and brakes automatically to achieve a 0.3 g deceleration if the collision is inevitable and the rider does not react. However, if the rider does brake, full braking force is applied automatically. Previous research into the potential benefits of MAEB has shown encouraging results. However, this was based on MAEB triggering algorithms designed for motorcycle crashes involving impacts with fixed objects and rear-end crashes. To estimate the full potential benefit of MAEB, there is a need to understand the full spectrum of motorcycle crashes and further develop triggering algorithms that apply to a wider spectrum of crash scenarios. In-depth crash data from 3 different countries were used: 80 hospital admittance cases collected during 2012-2013 within a 3-h driving range of Sydney, Australia, 40 crashes with Injury Severity Score (ISS)>15 collected in the metropolitan area of Florence, Italy, during 2009-2012, and 92 fatal crashes that occurred in Sweden during 2008-2009. In the first step, the potential applicability of MAEB among the crashes was assessed using a decision tree method. To achieve this, a new triggering algorithm for MAEB was developed to address crossing scenarios as well as crashes involving stationary objects. In the second step, the potential benefit of MAEB across the applicable crashes was examined by using numerical computer simulations. Each crash was reconstructed twice-once with and once without MAEB deployed. The principal finding is that using the new triggering algorithm, MAEB is seen to apply to a broad range of multivehicle motorcycle crashes. Crash mitigation was achieved through reductions in impact speed of up to approximately 10 percent, depending on the crash scenario and the initial vehicle pre-impact speeds. This research is the first attempt to evaluate MAEB with simulations on a broad range of crash scenarios using in-depth data. The results give further insights into the feasibility of MAEB in different speed ranges. It is clear then that MAEB is a promising technology that warrants further attention by researchers, manufacturers, and regulators.
An empirical analysis of farm vehicle crash injury severities on Iowa's public road system.
Gkritza, Konstantina; Kinzenbaw, Caroline R; Hallmark, Shauna; Hawkins, Neal
2010-07-01
Farm vehicle crashes are a major safety concern for farmers as well as all other users of the public road system in agricultural states. Using data on farm vehicle crashes that occurred on Iowa's public roads between 2004 and 2006, we estimate a multinomial logit model to identify crash-, farm vehicle-, and driver-specific factors that determine farm vehicle crash injury severity outcomes. Estimation findings indicate that there are crash patterns (rear-end manner of collision; single-vehicle crash; farm vehicle crossed the centerline or median) and conditions (obstructed vision and crash in rural area; dry road, dark lighting, speed limit 55 mph or higher, and harvesting season), as well as farm vehicle and driver-contributing characteristics (old farm vehicle, young farm vehicle driver), where targeted intervention can help reduce the severity of crash outcomes. Determining these contributing factors and their effect is the first step to identifying countermeasures and safety strategies in a bid to improve transportation safety for all users on the public road system in Iowa as well as other agricultural states. Copyright 2010 Elsevier Ltd. All rights reserved.
The effects of roadway characteristics on farm equipment crashes: A GIS approach
NASA Astrophysics Data System (ADS)
Greenan, Mitchell Joseph
Tractors and other self-propelled farm equipment, such as combines, sprayers, and towed grain carts, are often used on public roadways as the primary means for traveling from homestead to homestead or from homestead to a distributer. Increased roadway exposure has led to a growing concern for crashes involving farm equipment on the public roadway. A handful of studies exist examining public roadway crashes involving farm equipment using crash data, but none thus far have evaluated road segment data to identify road-specific risk factors. The objective of this study is to identify if roadway characteristics (traffic density, speed limit, road type, surface type, road width, and shoulder width) affect the risk of a crash involving farm equipment on Iowa public roadways. A retrospective cohort study of Iowa roads was conducted to identify the types of roads that are at an increased risk of having a farm-equipment crash on them. Crash data from the Iowa Department of Transportation (to identify crashes) were spatial linked to Iowa roadway data using Geographic Information Systems (GIS). Logistic regression was used to calculate ORs and 95% CL. Out of 319,705 road segments in Iowa, 0.4% segments (n=1,337) had a farm equipment crash from 2005-2011. The odds of having a farm equipment crash were significantly higher for road segments with increased traffic density and speed limit. Roads with an average daily traffic volume of at least 1,251 vehicles were at a 5.53 times greater odds of having a crash than roads with a daily traffic volume between 0-30 vehicles. (CI: 3.90-7.83). Roads with a posted speed limit between 50mph and 60mph were at a 4.88 times greater odds of having a crash than roads with a posted speed limit of 30mph or less. (CI: 3.85-6.20). Specific roadway characteristics such as roadway and shoulder width were also associated with the risk of a crash. For every 5 foot increase in road width, the odds for a crash decreased by 6 percent (CI: 0.89-0.99) and for every 5 foot increase in shoulder width, the odds of a crash decreased by 8 percent. (CI: 0.86-0.98). Although not statically significant, unpaved roads increased the odds of a crash by 17 percent. (CI: 0.91-1.50) Lastly, it was found that Farm to Market routes increased the odds of a crash by two fold compared to local roads (which make up roughly 67 percent of Iowa public roads). (CI: 1.72-2.43) When the same model was stratified by rurality (urban/rural), it was found that high traffic density leads to a higher risk of a crash in rural areas. Iowa routes and Farm to Market routes had a greater odds of a crash in urban than rural areas, and road and shoulder width were more protective in rural than urban areas. When only using roads with a crash involving an injury versus all other roads as the outcome, Iowa routes and roads with increased speed limits had higher odds for an injury-involved crash, while increased road width were more protective against crashes involving injuries. Findings from the study suggest that several roadway characteristics were associated with farm-equipment crashes. Through administrative and engineering controls, the six static explanatory variables used in this study may be modified to decrease the risk of a farm equipment crash. Speed limit can be modified through administrative controls while traffic density, road and shoulder width, road type, and surface type can be modified through engineering controls. Results from this study provide information that will aid policy-makers in developing safer roads for farm equipment.
Goldenbeld, Charles; Reurings, Martine; Van Norden, Yvette; Stipdonk, Henk
2013-01-01
To establish the statistical relationship between offenses and crashes when the unit of analysis is the vehicle instead of the driver, to show the influence of the severity (e.g., minor speed offenses) on this relationship, and to research whether the form of this relationship is similar in different enforcement contexts. An exploratory analysis was conducted using Dutch traffic offense and crash data. Crash data included all police-registered crashes involving motorized and registered vehicles in 2009; offense data included all non-criminal traffic offenses registered during 2005-2009 (mostly camera detected). Together these comprise an estimated 97 percent of all traffic offenses registered in this period. The analysis was done on a level of identified vehicles rather than persons. Vehicles involved in crashes were matched to vehicles involved in traffic offenses. The offense frequency distributions of registered crash involved vehicles and a random selection of vehicles was analyzed. Two comparisons were made: (1) privately owned vehicles versus company-owned vehicles and (2) vehicles for which only minor speed offenses were registered versus vehicles for which at least one major speed offense was registered. An increase in traffic offense frequency coincides with a stronger increase in relative crash involvement. This relationship was adequately described by a power function. The slightly more than linear increase in the crash risk for vehicles with only minor speed offenses suggests that minor speed offenses (<10 km/h over the limit) contributed slightly to crashes. This relationship was unlikely to be caused by increased distance traveled only. For vehicles with at least one or more major speed violation an approximately quadratic increase of crash risk with increasing speed offense frequency was found. A comparison of Dutch and Canadian data showed a much more progressive offense-crash relationship in the Dutch data. The crash involvement of vehicles increased more than linearly with the number of minor traffic violations. Thus, automatic detection of minor offenses bears relevance to safety. The substantial increase in crash rates with speed offense frequency for vehicles with at least one major speed violation suggests that these vehicles represent a specific group with a significantly increased crash risk, especially in the case of many minor offenses. The more progressive relationship between offenses and crashes in The Netherlands when compared to Canada was hypothesized to result from the higher intensity camera enforcement levels and less severe consequences in the Dutch enforcement and adjudication system.
Lord, Dominique; Washington, Simon P; Ivan, John N
2005-01-01
There has been considerable research conducted over the last 20 years focused on predicting motor vehicle crashes on transportation facilities. The range of statistical models commonly applied includes binomial, Poisson, Poisson-gamma (or negative binomial), zero-inflated Poisson and negative binomial models (ZIP and ZINB), and multinomial probability models. Given the range of possible modeling approaches and the host of assumptions with each modeling approach, making an intelligent choice for modeling motor vehicle crash data is difficult. There is little discussion in the literature comparing different statistical modeling approaches, identifying which statistical models are most appropriate for modeling crash data, and providing a strong justification from basic crash principles. In the recent literature, it has been suggested that the motor vehicle crash process can successfully be modeled by assuming a dual-state data-generating process, which implies that entities (e.g., intersections, road segments, pedestrian crossings, etc.) exist in one of two states-perfectly safe and unsafe. As a result, the ZIP and ZINB are two models that have been applied to account for the preponderance of "excess" zeros frequently observed in crash count data. The objective of this study is to provide defensible guidance on how to appropriate model crash data. We first examine the motor vehicle crash process using theoretical principles and a basic understanding of the crash process. It is shown that the fundamental crash process follows a Bernoulli trial with unequal probability of independent events, also known as Poisson trials. We examine the evolution of statistical models as they apply to the motor vehicle crash process, and indicate how well they statistically approximate the crash process. We also present the theory behind dual-state process count models, and note why they have become popular for modeling crash data. A simulation experiment is then conducted to demonstrate how crash data give rise to "excess" zeros frequently observed in crash data. It is shown that the Poisson and other mixed probabilistic structures are approximations assumed for modeling the motor vehicle crash process. Furthermore, it is demonstrated that under certain (fairly common) circumstances excess zeros are observed-and that these circumstances arise from low exposure and/or inappropriate selection of time/space scales and not an underlying dual state process. In conclusion, carefully selecting the time/space scales for analysis, including an improved set of explanatory variables and/or unobserved heterogeneity effects in count regression models, or applying small-area statistical methods (observations with low exposure) represent the most defensible modeling approaches for datasets with a preponderance of zeros.
Analyses of rear-end crashes based on classification tree models.
Yan, Xuedong; Radwan, Essam
2006-09-01
Signalized intersections are accident-prone areas especially for rear-end crashes due to the fact that the diversity of the braking behaviors of drivers increases during the signal change. The objective of this article is to improve knowledge of the relationship between rear-end crashes occurring at signalized intersections and a series of potential traffic risk factors classified by driver characteristics, environments, and vehicle types. Based on the 2001 Florida crash database, the classification tree method and Quasi-induced exposure concept were used to perform the statistical analysis. Two binary classification tree models were developed in this study. One was used for the crash comparison between rear-end and non-rear-end to identify those specific trends of the rear-end crashes. The other was constructed for the comparison between striking vehicles/drivers (at-fault) and struck vehicles/drivers (not-at-fault) to find more complex crash pattern associated with the traffic attributes of driver, vehicle, and environment. The modeling results showed that the rear-end crashes are over-presented in the higher speed limits (45-55 mph); the rear-end crash propensity for daytime is apparently larger than nighttime; and the reduction of braking capacity due to wet and slippery road surface conditions would definitely contribute to rear-end crashes, especially at intersections with higher speed limits. The tree model segmented drivers into four homogeneous age groups: < 21 years, 21-31 years, 32-75 years, and > 75 years. The youngest driver group shows the largest crash propensity; in the 21-31 age group, the male drivers are over-involved in rear-end crashes under adverse weather conditions and the 32-75 years drivers driving large size vehicles have a larger crash propensity compared to those driving passenger vehicles. Combined with the quasi-induced exposure concept, the classification tree method is a proper statistical tool for traffic-safety analysis to investigate crash propensity. Compared to the logistic regression models, tree models have advantages for handling continuous independent variables and easily explaining the complex interaction effect with more than two independent variables. This research recommended that at signalized intersections with higher speed limits, reducing the speed limit to 40 mph efficiently contribute to a lower accident rate. Drivers involved in alcohol use may increase not only rear-end crash risk but also the driver injury severity. Education and enforcement countermeasures should focus on the driver group younger than 21 years. Further studies are suggested to compare crash risk distributions of the driver age for other main crash types to seek corresponding traffic countermeasures.
Naimi, Timothy S; Xuan, Ziming; Sarda, Vishnudas; Hadland, Scott E; Lira, Marlene C; Swahn, Monica H; Voas, Robert B; Heeren, Timothy C
2018-05-29
Motor vehicle crashes are a leading cause of mortality. However, the association between the restrictiveness of the alcohol policy environment (ie, based on multiple existing policies) and alcohol-related crash fatalities has not been characterized previously to date. To examine the association between the restrictiveness of state alcohol policy environments and the likelihood of alcohol involvement among those dying in motor vehicle crashes in the United States. This investigation was a repeated cross-sectional study in which state alcohol policies (operationalized by the Alcohol Policy Scale [APS]) from 1999 to 2014 were related to motor vehicle crash fatalities from 2000 to 2015 using data from the Fatality Analysis Reporting System (1-year lag). Alternating logistic regression models and generalized estimating equations were used to account for clustering of multiple deaths within a crash and of multiple crashes occurring within states. The study also examined independent associations of mutually exclusive subgroups of policies, including consumption-oriented policies vs driving-oriented policies. The study setting was the 50 US states. Participants were 505 614 decedents aged at least 21 years from motor vehicle crashes from 2000 to 2015. Odds that a crash fatality was alcohol related (fatality stemmed from a crash in which ≥1 driver had a blood alcohol concentration [BAC] ≥0.08%). From 2000 to 2015, there were 505 614 adult motor vehicle crash fatalities in the United States, of which 178 795 (35.4%) were alcohol related. Each 10-percentage point increase in the APS score (corresponding to more restrictive state policies) was associated with reduced individual-level odds of alcohol involvement in a crash fatality (adjusted odds ratio [aOR], 0.90; 95% CI, 0.89-0.91); results were consistent among most demographic and crash-type strata. More restrictive policies also had protective associations with alcohol involvement among crash fatalities associated with BACs from greater than 0.00% to less than 0.08%. After accounting for driving-oriented policies, consumption-oriented policies were independently protective for alcohol-related crash fatalities (aOR, 0.97; 95% CI, 0.96-0.98 based on a 10-percentage point increased APS score). Strengthening alcohol policies, including those that do not specifically target impaired driving, could reduce alcohol-related crash fatalities. Policies may also protect against crash fatalities involving BAC levels below the current legal limit for driving in the United States.
Relationship of Near-Crash/Crash Risk to Time Spent on a Cell Phone While Driving.
Farmer, Charles M; Klauer, Sheila G; McClafferty, Julie A; Guo, Feng
2015-01-01
The objective of this study was to examine in a naturalistic driving setting the dose-response relationship between cell phone usage while driving and risk of a crash or near crash. How is the increasing use of cell phones by drivers associated with overall near-crash/crash risk (i.e., during driving times both on and off the phone)? Day-to-day driving behavior of 105 volunteer subjects was monitored over a period of 1 year. A random sample was selected comprised of 4 trips from each month that each driver was in the study, and in-vehicle video was used to classify driver behavior. The proportion of driving time spent using a cell phone was estimated for each 3-month period and correlated with overall crash and near-crash rates for each period. Thus, it was possible to test whether changes in an individual driver's cell phone use over time were associated with changes in overall near-crash/crash risk. Drivers in the study spent 11.7% of their driving time interacting with a cell phone, primarily talking on the phone (6.5%) or simply holding the phone in their hand or lap (3.7%). The risk of a near-crash/crash event was approximately 17% higher when the driver was interacting with a cell phone, due primarily to actions of reaching for/answering/dialing, which nearly triples risk (relative risk = 2.84). However, the amount of driving time spent interacting with a cell phone did not affect a driver's overall near-crash/crash risk. Vehicle speeds within 6 s of the beginning of each call on average were 5-6 mph lower than speeds at other times. Results of this naturalistic driving study are consistent with the observation that increasing cell phone use in the general driving population has not led to increased crash rates. Although cell phone use can be distracting and crashes have occurred during this distraction, overall crash rates appear unaffected by changes in the rate of cell phone use, even for individual drivers. Drivers compensate somewhat for the distraction by conducting some of the more demanding tasks, such as reaching for or dialing a cell phone, at lower speeds. It is also possible that cell phones and other electronic devices in cars are changing how drivers manage their attention to various tasks and/or changing the kinds of secondary tasks in which they engage.
2009 New Mexico traffic crash information
DOT National Transportation Integrated Search
2011-05-01
This edition of New Mexico Traffic Crash Information reviews traffic crash data in New Mexico from January through December, 2009. It presents crash data in the form of graphs for those who prefer an impressionistic view and tables for those who requ...
1999 New Mexico traffic crash information
DOT National Transportation Integrated Search
2001-03-01
This edition of New Mexico Traffic Crash Information reviews traffic crash data in New MExico from January through Decemeber, 1999. It presents crash data in the form of graphs for those who prefer an impressionistic view and tables for those who req...
2002 Oregon motor carrier crash rate tables
DOT National Transportation Integrated Search
2003-11-01
The State Highway Motor Carrier Crash Rate Tables is a publication in four parts. Its : purpose is to assist readers in computing Motor Carrier crash rates for specific sections : of State Highways. This report differs from the State Highway Crash Ra...
Illinois crash facts and statistics, 2010
DOT National Transportation Integrated Search
2011-01-01
The number of reported motor vehicle crashes decreased from the previous year to fewer than 290,000 crashes in calendar year 2010. In addition, the number of persons injured in crashes dropped below 89,000 and the number of fatalities on Illinois roa...
Crashes involving farm tractors and other farm vehicles/equipment in North Carolina 1995-1999
DOT National Transportation Integrated Search
2000-04-01
Tables and figures are shown to depict a statistical representation of crashes involving farm tractors and other farm vehicles or equipment, in North Carolina. Information displayed includes crash frequency, crashes by county, accident severity, type...
1999 Iowa crash facts : a summary of motor vehicle crash statistics on Iowa roadways
DOT National Transportation Integrated Search
1999-01-01
All information concerning Iowa traffic crashes was taken from report forms : provided by investigating officers and drivers involved in crashes. : All statistics are gathered and calculated by the Iowa Department of Transportations Office of Driv...
2010 Wisconsin traffic crash facts
DOT National Transportation Integrated Search
2011-01-01
562 persons were killed in Wisconsin motor vehicle traffic crashes. This is an average of just over one life lost each day on Wisconsin traffic arteries. : 40,889 persons were injured in 29,380 reported injury crashes and 517 fatal crashes. 3,845, or...
GIS-Based crash referencing and analysis system
DOT National Transportation Integrated Search
1999-02-01
One area where a Geographic Information System (GIS) has yet to be extensively applied is in the analysis of crash data. Computerized crash analysis systems in which crash data, roadway inventory data, and traffic operations data can be merged are us...
2003 Oregon motor carrier crash rate tables
DOT National Transportation Integrated Search
2005-04-01
The State Highway Motor Carrier Crash Rate Tables is a publication in four parts. Its : purpose is to assist readers in computing Motor Carrier crash rates for specific sections of : State Highways. This report differs from the State Highway Crash Ra...
2006 New Mexico traffic crash information
DOT National Transportation Integrated Search
2007-10-01
This edition of New Mexico Traffi c Crash Information : reviews traffi c crash data in New Mexico from January : through December, 2006. It presents crash data in the : form of graphs for those who prefer an impressionistic view : and tables for thos...
2007 New Mexico traffic crash information
DOT National Transportation Integrated Search
2009-12-01
This edition of New Mexico Traffi c Crash Information reviews : traffi c crash data in New Mexico from January through December, : 2007. It presents crash data in the form of graphs for those who : prefer an impressionistic view and tables for those ...
Exploring rear-end roadway crashes from the driver's perspective
DOT National Transportation Integrated Search
1998-10-01
This pilot study examined rear-end crashes from the driver's perspective to identify self-reported reasons and causes of such crashes, to identify commonalities in the self-reported causes and locations and circumstances of these crashes, and to expl...
DOT National Transportation Integrated Search
2011-08-01
The Backing crash Countermeasures project, part of the U.S. Department of Transportation's Advanced Crash Avoidance Technologies (ACAT) program, developed a basic methodological framework and computerbased simulation model to estimate the effectiv...
2004 Oregon motor carrier crash rate tables
DOT National Transportation Integrated Search
2005-11-01
The State Highway Motor Carrier Crash Rate Tables is a publication in four parts. Its : purpose is to assist readers in computing Motor Carrier crash rates and Truck-At-Fault : crash rates for specific sections of State Highways. This report differs ...
2006 Oregon motor carrier crash rate tables
DOT National Transportation Integrated Search
2007-08-01
The State Highway Motor Carrier Crash Rate Tables is a publication in four parts. Its : purpose is to assist readers in computing Motor Carrier crash rates and Truck-At-Fault : crash rates for specific sections of State Highways. This report differs ...
2009 Oregon motor carrier crash rate tables
DOT National Transportation Integrated Search
2010-11-01
The State Highway Motor Carrier Crash Rate Tables is a publication in four parts. Its purpose is to assist readers in computing Motor Carrier crash rates and Truck-At-Fault crash rates for specific sections of State Highways. This report differs from...
2005 Oregon motor carrier crash rate tables
DOT National Transportation Integrated Search
2006-01-01
The State Highway Motor Carrier Crash Rate Tables is a publication in four parts. Its : purpose is to assist readers in computing Motor Carrier crash rates and Truck-At-Fault : crash rates for specific sections of State Highways. This report differs ...
2007 Oregon motor carrier crash rate tables
DOT National Transportation Integrated Search
2008-11-01
The State Highway Motor Carrier Crash Rate Tables is a publication in four parts. Its : purpose is to assist readers in computing Motor Carrier crash rates and Truck-At-Fault : crash rates for specific sections of State Highways. This report differs ...
Fatal Crash Involvements -- What Are The Odds?
DOT National Transportation Integrated Search
1997-07-01
The risk of being involved in a fatal crash varies considerably depending on : specific crash characteristics, i.e., those of the driver, vehicle and : environment. A generally accepted measure of the risk of a fatal crash is the : ratio between the ...
Traffic safety facts : distracted driving 2009
DOT National Transportation Integrated Search
2010-09-01
In 2009, there were 30,797 fatal crashes in the United States, : which involved 45,230 drivers. In those crashes, 33,808 : people were killed. Distraction was reported for 11 percent : (5,084) of the drivers involved in fatal crashes. In these crashe...
A Front-End Analysis Of Rear-End Crashes
DOT National Transportation Integrated Search
1992-05-17
THIS PAPER DESCRIBES THE APPLICATION OF A SEVEN-STEP CRASH PROBLEM ANALYSIS METHODOLOGY, AS DESCRIBED IN THE PRECEDING PAPER BY LEASURE (1), TO REAR-END CRASHES. THE PAPER SHOWS HOW MODELING OF REAR-END CRASH SCENARIOS AND CANDIDATE COUNTERMEASURE AC...
1997 Iowa crash summary : a summary of motor vehicle crash statistics on Iowa roadways
DOT National Transportation Integrated Search
1997-01-01
All information concerning Iowa : traffic crashes was taken from report forms provided by investigating officers and drivers involved in : crashes. : All statistics are gathered and calculated by the Iowa Department of Transportations Office of Dr...
1996 Iowa crash summary : a summary of motor vehicle crash statistics on Iowa roadways
DOT National Transportation Integrated Search
1996-01-01
All information concerning Iowa : traffic crashes was taken from report forms provided by investigating officers and drivers involved in : crashes. : All statistics are gathered and calculated by the Iowa Department of Transportations Office of Dr...
1998 Iowa crash summary : a summary of motor vehicle crash statistics on Iowa roadways
DOT National Transportation Integrated Search
1998-01-01
All information concerning Iowa : traffic crashes was taken from report forms provided by investigating officers and drivers involved in : crashes. : All statistics are gathered and calculated by the Iowa Department of Transportations Office of Dr...
Pre-crash scenario framework for crash avoidance systems based on vehicle-to-vehicle communications
DOT National Transportation Integrated Search
2011-06-13
This paper prioritizes and statistically describes precrash : scenarios as a basis for the identification of : crash avoidance functions enhanced or enabled by : vehicle-to-vehicle (V2V) communication technology. : Pre-crash scenarios depict vehicle ...
Guidelines for reducing wrong-way crashes on freeways.
DOT National Transportation Integrated Search
2014-05-01
Each year, hundreds of fatal wrong-way driving (WWD) crashes occur across the United States, and thousands : of injuries are reported in traffic crashes caused by wrong-way drivers. Although WWD crashes have been a : concern since the advent of acces...
Spatially referenced crash data system for application to commercial motor vehicle crashes.
DOT National Transportation Integrated Search
2003-05-01
The Maryland Spatial Analysis of Crashes (MSAC) project involves the design of a : prototype of a geographic information system (GIS) for the State of Maryland that has : the capability of providing online crash information and statistical informatio...
2008 Oregon motor carrier crash rate tables
DOT National Transportation Integrated Search
2009-10-01
The State Highway Motor Carrier Crash Rate Tables is a publication in four parts. Its : purpose is to assist readers in computing Motor Carrier crash rates and Truck-At-Fault : crash rates for specific sections of State Highways. This report differs ...
Relationship between speed and lateral position on curves.
DOT National Transportation Integrated Search
2012-09-01
Excessive speed is often cited as a primary driver factor in crashes, particularly rural two-lane crashes. It has also been suggested that speed plays a significant role in crashes on curves. : However, the relationship between speed and crashes on c...
Injury risks for on-road farm equipment and horse and buggy crashes in Pennsylvania: 2010-2013.
Gorucu, Serap; Murphy, Dennis J; Kassab, Cathy
2017-04-03
The purpose of this study was to investigate characteristics associated with farm equipment and horse and buggy roadway crashes in relation to person, incident, and injury characteristics to identify appropriate points for injury incident prevention. Information on crashes occurring on public roads during the years 2010-2013 was obtained from the Pennsylvania Department of Transportation (PennDOT) and analyzed. There were 344 farm equipment and 246 horse and buggy crashes during the 4-year study period. These crashes involved 666 and 504 vehicles and 780 and 838 people, respectively. In incidents with farm equipment, the non-farm equipment drivers had an almost 2 times greater injury risk than farm equipment operators. Horse and buggy crashes were almost 3 times more injurious to the horse and buggy drivers than the drivers of the other vehicles. The average crash rate for farm equipment was 198.4 crashes per 100,000 farm population and for horse and buggy the crash rate was calculated as 89.4 crashes per 100,000 Amish population per year. This study suggests that road safety and public health programs should focus not only on farm equipment operators and horse and buggy drivers but on other motorists sharing the roadway with them.
Impact of federal compliance reviews of trucking companies in reducing highway truck crashes.
Chen, Guang Xiang
2008-01-01
The compliance review (CR) is a federal program monitoring motor carrier safety performance and regulatory compliance. This study sought to assess the impact of CRs on reviewed trucking companies in reducing truck crashes. Data was from the Motor Carrier Management Information System. Study subjects were trucking companies established during 1990-1995, had at least one truck, and remained active until April 2004. Truck crash data of these companies was examined from 1996 to 2003. The crash rates in 2003 and annual percentage changes in number of crashes were computed. Analyses were stratified by company size, organization, operation classification, and safety rating. Companies that received CRs had a higher crash rate than never-reviewed companies. Reviewed companies experienced a 39-15% reduction in number of crashes in the year the CR was performed. The reduction in crashes was observed in all reviewed companies regardless of company size, operation classification, type of organization, or safety rating. The reduction in crashes was sustained for at least 7 years after CRs. The study results were controlled for the year in which CRs were performed, crash trend, and CR selection bias. However, further studies, especially a randomized prospective longitudinal study, are needed to overcome the limitations that are associated with an observation study.
Zhang, Yuting; Yan, Xuedong; Li, Xiaomeng; Wu, Jiawei; Dixit, Vinayak V
2018-06-19
Red-light running (RLR) has been identified as one of the prominent contributing factors involved in signalized intersection crashes. In order to reduce RLR crashes, primarily, a better understanding of RLR behavior and crashes is needed. In this study, three RLR crash types were extracted from the general estimates system (GES), including go-straight (GS) RLR vehicle colliding with go-straight non-RLR vehicle, go-straight RLR vehicle colliding with left-turn (LT) non-RLR vehicle, and left-turn RLR vehicle colliding with go-straight non-RLR vehicle. Then, crash features within each crash type scenario were compared, and risk analyses of GS RLR and LT RLR were also conducted. The results indicated that for the GS RLR driver, the speed limit displayed the highest effects on the percentages of GS RLR collision scenarios. For the LT RLR driver, the number of lanes displayed the highest effects on the percentages of LT RLR collision scenarios. Additionally, the drivers who were older than 50 years, distracted, and had a limited view were more likely to be involved in LT RLR accidents. Furthermore, the speeding drivers were more likely to be involved in GS RLR accidents. These findings could give a comprehensive understanding of RLR crash features and propensities for each RLR crash type.
Influence of pavement condition on horizontal curve safety.
Buddhavarapu, Prasad; Banerjee, Ambarish; Prozzi, Jorge A
2013-03-01
Crash statistics suggest that horizontal curves are the most vulnerable sites for crash occurrence. These crashes are often severe and many involve at least some level of injury due to the nature of the collisions. Ensuring the desired pavement surface condition is one potentially effective strategy to reduce the occurrence of severe accidents on horizontal curves. This study sought to develop crash injury severity models by integrating crash and pavement surface condition databases. It focuses on developing a causal relationship between pavement condition indices and severity level of crashes occurring on two-lane horizontal curves in Texas. In addition, it examines the suitability of the existing Skid Index for safety maintenance of two-lane curves. Significant correlation is evident between pavement condition and crash injury severity on two-lane undivided horizontal curves in Texas. Probability of a crash becoming fatal is appreciably sensitive to certain pavement indices. Data suggested that road facilities providing a smoother and more comfortable ride are vulnerable to severe crashes on horizontal curves. In addition, the study found that longitudinal skid measurement barely correlates with injury severity of crashes occurring on curved portions. The study recommends exploring the option of incorporating lateral friction measurement into Pavement Management System (PMS) databases specifically at curved road segments. Copyright © 2012 Elsevier Ltd. All rights reserved.
The real-world safety potential of connected vehicle technology.
Doecke, Sam; Grant, Alex; Anderson, Robert W G
2015-01-01
This article estimates the safety potential of a current commercially available connected vehicle technology in real-world crashes. Data from the Centre for Automotive Safety Research's at-scene in-depth crash investigations in South Australia were used to simulate the circumstances of real-world crashes. A total of 89 crashes were selected for inclusion in the study. The crashes were selected as representative of the most prevalent crash types for injury or fatal crashes and had potential to be mitigated by connected vehicle technology. The trajectory, speeds, braking, and impact configuration of the selected in-depth cases were replicated in a software package and converted to a file format allowing "replay" of the scenario in real time as input to 2 Cohda Wireless MK2 onboard units. The Cohda Wireless onboard units are a mature connected vehicle technology that has been used in both the German simTD field trial and the U.S. Department of Transport's Safety Pilot project and have been tuned for low false alarm rates when used in the real world. The crash replay was achieved by replacing each of the onboard unit Global Positioning System (GPS) inputs with the simulated data of each of the involved vehicles. The time at which the Cohda Wireless threat detection software issued an elevated warning was used to calculate a new impact speed using 3 different reaction scenarios and 2 levels of braking. It was found that between 37 and 86% of the simulated crashes could be avoided, with highest percentage due a fully autonomous system braking at 0.7 g. The same system also reduced the impact speed relative to the actual crash in all cases. Even when a human reaction time of 1.2 s and moderate braking of 0.4 g was assumed, the impact speed was reduced in 78% of the crashes. Crash types that proved difficult for the threat detection engine were head-on crashes where the approach angle was low and right turn-opposite crashes. These results indicate that connected vehicle technology can be greatly beneficial in real-world crash scenarios and that this benefit would be maximized by having the vehicle intervene autonomously with heavy braking. The crash types that proved difficult for the connected vehicle technology could be better addressed if controller area network (CAN) information is available, such as steering wheel angle, so that driver intent can be inferred sooner. More accurate positioning in the real world (e.g., combining satellite positioning and accelerometer data) would allow the technology to be more effective for near-collinear head-on and rear-end crashes, because the low approach angles that are common in such crashes are currently ignored in order to minimize false alarms due to positioning uncertainty.
Children in crashes: mechanisms of injury and restraint systems
Lapner, Peter C.; McKay, Morag; Howard, Andrew; Gardner, Bill; German, Alan; Letts, Mervyn
2001-01-01
Objectives To explore the levels of protection offered to children involved in motor vehicle collisions. Design A joint study by the Children’s Hospital of Eastern Ontario (CHEO) and Transport Canada, Ottawa, conducted in 2 phases: retrospective from 1990 to 1997 and prospective from 1998 to 2000. Setting CHEO, a university affiliated tertiary care centre. Patients Children admitted to CHEO between 1990 and 2000 with spinal trauma due to motor vehical crashes (MVCs). Phase 1 of the study involved analysis, in a series of 45 children after MVAs, by location of spinal injury versus belt type. Phase 2 was a prospective study of 22 children injured in 15 MVAs. Interventions A biomechanical assessment of the vehicle and its influence on the injuries sustained. Main outcome measures The nature and extent of the injuries sustained, and the vehicle dynamics and associated occupant kinematics. Results The odds ratio of sustaining a spinal injury while wearing a 2-point belt versus a 3-point belt was 24 (95% confidence interval 2.0–2.45, p < 0.1), indicating a much higher incidence with a lap belt than a shoulder strap. Conclusions Proper seat-belt restraint reduces the morbidity in children involved in MVCs. Children under the age of 12 years should not be front-seat passengers until the sensitivity of air bags has been improved. Three-point pediatric seat belts should be available for family automobiles to reduce childhood trauma in MVCs. PMID:11764879
Sander, Ulrich; Lubbe, Nils
2018-06-01
Car occupants account for one third of all junction fatalities in the European Union. Driver warning can reduce intersection accidents by up to 50 percent; adding Autonomous Emergency Braking (AEB) delivers a reduction of up to 70 percent. However, these findings are based on an assumed 100 percent equipment rate, which may take decades to achieve. Our study investigates the relationship between intersection AEB market penetration rates and avoidance of accidents and injuries in order to guide implementation strategies. Additionally, residual accident characteristics (impact configurations and severity) are analyzed to provide a basis for future in-crash protection requirements. We determined which accidents would have been avoided through the use of an Intersection AEB system with different sensor field-of-views (180° and 120°) by means of re-simulating the pre-crash phase of 792 straight crossing path (SCP) car-to-car accidents recorded in the German In-Depth Accident Study (GIDAS) and the associated Pre-Crash Matrix (PCM). Intersection AEB was activated when neither of the conflict opponents could avoid the crash through reasonable braking or steering reactions. For not-avoided accidents, we used the Kudlich-Slibar rigid body impulse model to calculate the change of velocity during the impact as a measure of impact severity and the principal direction of force. Accident avoidance over market penetration is not linear but exponential, with higher gains at low penetration rates and lower gains at higher rates. A wide field-of-view sensor (180°) substantially increased accident avoidance and injury mitigation rates compared to a 120° field-of-view sensor. For a 180° field-of-view sensor at 100 percent market penetration, about 80 percent of the accidents and 90 percent of the MAIS2 + F injuries could be avoided. For the remaining accidents, AEB intervention rarely affected side of impact. The median change of velocity (delta-V) of the remaining crashes reduces only marginally at low penetration rates but this reduction increases with higher penetration rates. With 100 percent market penetration, one quarter of the vehicles still involved in straight crossing path accidents will sustain a delta-V higher than 17 km/h. Intersection AEB is very effective. Enabling a fast initial implementation of systems with wide field-of-view sensor(s) and ensuring a high market penetration over the longer term is essential to achieve high crash avoidance and injury mitigation rates over time. The standards for in-crash protection must be high to mitigate injury in the unavoidable, residual accidents. Copyright © 2018 Elsevier Ltd. All rights reserved.
Motor vehicle crash-related subdural hematoma from real-world head impact data.
Urban, Jillian E; Whitlow, Christopher T; Edgerton, Colston A; Powers, Alexander K; Maldjian, Joseph A; Stitzel, Joel D
2012-12-10
Abstract Approximately 1,700,000 people sustain a traumatic brain injury (TBI) each year and motor vehicle crashes (MVCs) are a leading cause of hospitalization from TBI. Acute subdural hematoma (SDH) is a common intracranial injury that occurs in MVCs associated with high mortality and morbidity rates. In this study, SDH volume and midline shift have been analyzed in order to better understand occupant injury by correlating them to crash and occupant parameters. Fifty-seven head computed tomography (CT) scans were selected from the Crash Injury Research Engineering Network (CIREN) with Abbreviated Injury Scale (AIS) level 3+ SDH. Semi-automated methods were used to isolate the intracranial volume. SDH and additional occupant intracranial injuries were segmented across axial CT images, providing a total SDH injury volume. SDH volume was correlated to crash parameters and occupant characteristics. Results show a positive correlation between SDH volume and crash severity in near-side and frontal crashes. Additionally, the location of the resulting hemorrhage varied by crash type. Those with greater SDH volumes had significantly lower Glasgow Coma Scale (GCS) scores at the crash site in near-side crashes. Age and fracture type were found to be significant contributors to SDH volume. This study is a volumetric analysis of real world brain injuries and known MVC impacts. The results of this study demonstrate a relationship among SDH volume, crash mechanics, and occupant characteristics that provide a better understanding of the injury mechanisms of MVC-associated TBI.
Naznin, Farhana; Currie, Graham; Sarvi, Majid; Logan, David
2016-01-01
Streetcars/tram systems are growing worldwide, and many are given priority to increase speed and reliability performance in mixed traffic conditions. Research related to the road safety impact of tram priority is limited. This study explores the road safety impacts of tram priority measures including lane and intersection/signal priority measures. A before-after crash study was conducted using the empirical Bayes (EB) method to provide more accurate crash impact estimates by accounting for wider crash trends and regression to the mean effects. Before-after crash data for 29 intersections with tram signal priority and 23 arterials with tram lane priority in Melbourne, Australia, were analyzed to evaluate the road safety impact of tram priority. The EB before-after analysis results indicated a statistically significant adjusted crash reduction rate of 16.4% after implementation of tram priority measures. Signal priority measures were found to reduce crashes by 13.9% and lane priority by 19.4%. A disaggregate level simple before-after analysis indicated reductions in total and serious crashes as well as vehicle-, pedestrian-, and motorcycle-involved crashes. In addition, reductions in on-path crashes, pedestrian-involved crashes, and collisions among vehicles moving in the same and opposite directions and all other specific crash types were found after tram priority implementation. Results suggest that streetcar/tram priority measures result in safety benefits for all road users, including vehicles, pedestrians, and cyclists. Policy implications and areas for future research are discussed.
Stadter, Greg; Grabowski, Jurek G; Burke, Christine; Aldaghlas, Tayseer A; Robinson, Linda; Fakhry, Samir M
2008-12-01
Side impact crashes, the most lethal type, account for 26% of all motor vehicle crashes in the United States. The purpose of this study is to delineate side impact airbag (SIAB) deployment rates, injury rates, and analyze crash factors associated with SIAB deployment and occupant injury. All passenger vehicles equipped with SIABs that were involved in a side impact crash were identified from the National Automotive Sampling System database. Crashes with multiple impacts, ejections, unbelted drivers or rollovers were excluded from the study. The outcome variables of interest were SIAB deployment and driver injury. SIAB deployment was compared in similar crashes to analyze the impact on driver's injury severity score. Other crash factors were also examined to analyze what role they play in SIAB deployment rates and injury rates, such as plane of contact, striking object and Delta-V. The data set for this study contained 247 drivers in near and far side crashes in vehicles with installed SIABs. Overall SIAB deployment was 43% in side impact crashes. A significant factor associated with both the SIAB deployment rate and the driver's injury rate was increased Delta-V. SIABs do not deploy consistently in crashes with a high Delta-V or with a lateral primary direction of force and a front plane of contact. In these two scenarios, further research is warranted on SIAB deployments. With SIAB deployment, it appears drivers are able to sustain a higher Delta-V impact without serious injury.
Yue, Lishengsa; Abdel-Aty, Mohamed; Wu, Yina; Wang, Ling
2018-08-01
The Connected Vehicle (CV) technologies together with other Driving Assistance (DA) technologies are believed to have great effects on traffic operation and safety, and they are expected to impact the future of our cities. However, few research has estimated the exact safety benefits when all vehicles are equipped with these technologies. This paper seeks to fill the gap by using a general crash avoidance effectiveness framework for major CV&DA technologies to make a comprehensive crash reduction estimation. Twenty technologies that were tested in recent studies are summarized and sensitivity analysis is used for estimating their total crash avoidance effectiveness. The results show that crash avoidance effectiveness of CV&DA technology is significantly affected by the vehicle type and the safety estimation methodology. A 70% crash avoidance rate seems to be the highest effectiveness for the CV&DA technologies operating in the real-world environment. Based on the 2005-2008 U.S. GES Crash Records, this research found that the CV&DA technologies could lead to the reduction of light vehicles' crashes and heavy trucks' crashes by at least 32.99% and 40.88%, respectively. The rear-end crashes for both light vehicles and heavy trucks have the most expected crash benefits from the technologies. The paper also studies the effectiveness of Forward Collision Warning technology (FCW) under fog conditions, and the results show that FCW could reduce 35% of the near-crash events under fog conditions. Copyright © 2018 Elsevier Ltd. All rights reserved.
Injury Outcome in Crashes with Guardrail End Terminals.
Johnson, Nicholas S; Gabler, Hampton C
2015-01-01
The goal of this study is to evaluate the crash performance of guardrail end terminals in real-world crashes. Guardrail end terminals are installed at the ends of guardrail systems to prevent the rail from spearing through the car in an end-on collision. Recently, there has been a great deal of controversy as to the safety of certain widely used end terminal designs, partly because there is surprisingly little real-world crash data for end terminals. Most existing studies of end terminal crashes used data from prior to the mid-1990s. Since then, there have been large improvements to vehicle crashworthiness and seat belt usage rates, as well as new roadside safety hardware compliant with National Cooperative Highway Research Program (NCHRP) Report 350, "Recommended Procedures for the Safety Performance Evaluation of Highway Features." Additionally, most existing studies of injury in end terminal crashes do not account for factors such as the occurrence of rollover. This analysis uses more recent crash data that represent post-1990s vehicle fleet changes and account for a number of factors that may affect driver injury outcome and rollover occurrence. Passenger vehicle crashes coded as involving guardrail end terminals were identified in the set of police-reported crashes in Michigan in 2011 and 2012. End terminal performance was expected to be a function of end terminal system design. State crash databases generally do not identify specific end terminal systems. In this study, the coded crash location was used to obtain photographs of the crash site prior to the crash from Google Street View. These site photographs were manually inspected to identify the particular end terminal system involved in the crash. Multiple logistic regression was used to test for significant differences in the odds of driver injury and rollover between different terminal types while accounting for other factors. A total of 1,001 end terminal crashes from the 2011-2012 Michigan State crash data were manually inspected to identify the terminal that had been struck. Four hundred fifty-one crashes were found to be suitable for analysis. Serious to fatal driver injury occurred in 3.8% of end terminal crashes, moderate to fatal driver injury occurred in 11.8%, and 72.3% involved property damage only. No significant difference in moderate to fatal driver injury odds was observed between NCHRP 350 compliant end terminals and noncompliant terminals. Car drivers showed odds of moderate to fatal injury 3.6 times greater than LTV drivers in end terminal crashes. Rollover occurrence was not significantly associated with end terminal type. Car drivers have greater potential for injury in end terminal crashes than light truck/van/sport utility vehicle drivers. End terminal designs compliant with NCHRP 350 did not appear to carry different odds of moderate driver injury than noncompliant end terminals. The findings account for driver seat belt use, rollover occurrence, terminal orientation (leading/trailing), control loss, and the number of impact events. Rollover and nonuse of seat belts carried much larger increases in injury potential than end terminal type. Rollover did not appear to be associated with NCHRP 350 compliance.
Analysis of traffic crash data in Kentucky : 1997-2001.
DOT National Transportation Integrated Search
2002-08-01
This report documents an analysis of traffic crash data in Kentucky for the years of 1997 through 2001. A primary objective of this study was to determine average crash statistics for Kentucky highways. Average and critical numbers and rates of crash...
2001 Oregon motor carrier crash rate tables
DOT National Transportation Integrated Search
2002-11-01
This is a three-part report. This report differs from the State Highway Crash Rate : Tables in that it contains crash data on motor carrier crashes only, and does not include : data for highway spurs, frontage roads, and the non-add segments of...
2000 Oregon motor carrier crash rate tables
DOT National Transportation Integrated Search
2002-01-01
This is a three-part report. This report differs from the State Highway Crash Rate : Tables in that it contains crash data on motor carrier crashes only, and does not include : data for highway spurs, frontage roads, and the non-add segments of...
1999 Oregon motor carrier crash rate tables
DOT National Transportation Integrated Search
2000-12-01
This is a three-part report. This report differs from the State Highway Crash Rate : Tables in that it contains crash data on motor carrier crashes only, and does not include : data for highway spurs, frontage roads, and the non-add segments of...
Quantifying roadside assessment for highway safety.
DOT National Transportation Integrated Search
2017-09-01
Many of Kentuckys two-lane rural roads pose an above average risk for fixed object crashes. In Kentucky, run-off-road (ROR) collisions with fixed objects account for 18.9% of all crashes and 41.6% of fatal crashes. Accordingly, ROR crashes are a s...
Crash data and rates for age-sex groups of drivers, 1996
DOT National Transportation Integrated Search
1998-01-01
The results of this research note are based on 1996data for fatal crashes, driver licenses, and estimates of total crashes based upon data obtained from the nationally representative sample of crashes gathered in the General Estimates System (GES). T...
DOT National Transportation Integrated Search
2015-03-01
Lane departure crashes including single-vehicle-run-off-road crashes, opposite direction sideswipe and head-on crashes are considered the most sever : crashes and often dominated by sleep deprivation/fatigue, and distracted driving. According to the ...
Development of test scenarios for off-roadway crash countermeasures based on crash statistics
DOT National Transportation Integrated Search
2002-09-01
This report presents the results from an analysis of off-roadway crashes and proposes a set of crash-imminent scenarios to objectively test countermeasure systems for light vehicles (passenger cars, sport utility vehicles, vans, and pickup trucks) ba...
Analysis of traffic crash data in Kentucky (1997-2001)
DOT National Transportation Integrated Search
2002-08-01
This report documents an analysis of traffic crash data in Kentucky for the years of 1997 through 2001. A primary objective of this study was to determine average crash statistics for Kentucky highways. Average and critical numbers and rates of crash...
Analysis of traffic crash data in Kentucky (1996-2000)
DOT National Transportation Integrated Search
2001-09-01
This report documents an analysis of traffic crash data in Kentucky for the years of 1996 through 2000. A primary objective of this study was to determine average crash statistics for Kentucky highways. Average and critical numbers and rates of crash...
Analysis of traffic crash data in Kentucky : 1996-2000.
DOT National Transportation Integrated Search
2001-09-01
This report documents an analysis of traffic crash data in Kentucky for the years of 1996 through 2000. A primary objective of this study was to determine average crash statistics for Kentucky highways. Average and critical numbers and rates of crash...
Analysis of traffic crash data in Kentucky : 2004-2008.
DOT National Transportation Integrated Search
2009-09-01
The report documents an analysis of traffic crash data in Kentucky for the years of 2004 through 2008. A primary objective of this study was to determine average crash statistics for Kentucky highways. Average and critical numbers and rates of crashe...
Crash cost estimates by maximum police-reported injury severity within selected crash geometrics
DOT National Transportation Integrated Search
2005-10-01
This paper presents estimates for the economic (human capital) and comprehensive costs per crash for six KABCO groupings within 22 selected crash types and within two speed limit categories (=80 km/h (>= 50 mi/h)). The comp...
Evaluation of the locations of Kentucky's traffic crash data.
DOT National Transportation Integrated Search
2010-11-01
An evaluation of a random sample of crashes from 2009 was performed to assess the current accuracy of the crash data's location information.The location of the crash was compared to the presumed location using several report data elements such as nea...
Molnar, Amber O; Hiremath, Swapnil; Brown, Pierre A; Akbari, Ayub
2016-07-19
Many patients with kidney failure "crash" onto dialysis or initiate dialysis in an unplanned fashion. There are varying definitions, but essentially, a patient is labeled as having a crash dialysis start if he or she has little to no care by a nephrologist prior to starting dialysis. A patient is labeled as having an unplanned dialysis start when he or she starts dialysis with a catheter or during a hospitalization. Given the high prevalence and poor outcomes associated with crash and unplanned dialysis starts, it is important to establish a better understanding of patient risk factors. We will conduct a systematic review and meta-analysis with a focus on both crash and unplanned dialysis starts. The first objective will be to determine patient risk factors for crash and unplanned dialysis starts. Secondary objectives will be to determine the most common criteria used to define both crash and unplanned dialysis starts and to determine outcomes associated with crash and unplanned dialysis starts. We will search MEDLINE, EMBASE and Cochrane Library from inception to the present date for all studies that report the characteristics and outcomes of patients who have crash vs. non-crash dialysis starts or unplanned vs. planned dialysis starts. We will also extract from included studies the criteria used to define crash and unplanned dialysis starts. If there are any eligible randomized controlled trials, quality assessment will be performed using the Cochrane Risk of Bias Assessment Tool. Observational studies will be evaluated using the Newcastle-Ottawa Scale. Data will be pooled in meta-analysis if deemed appropriate. The results of this review will inform the design of strategies to help reduce the incidence of crash and unplanned dialysis starts. Prospero CRD42016032916.
Direct medical costs of motorcycle crashes in Ontario
Pincus, Daniel; Wasserstein, David; Nathens, Avery B.; Bai, Yu Qing; Redelmeier, Donald A.; Wodchis, Walter P.
2017-01-01
BACKGROUND: There is no reliable estimate of costs incurred by motorcycle crashes. Our objective was to calculate the direct costs of all publicly funded medical care provided to individuals after motorcycle crashes compared with automobile crashes. METHODS: We conducted a population-based, matched cohort study of adults in Ontario who presented to hospital because of a motorcycle or automobile crash from 2007 through 2013. For each case, we identified 1 control absent a motor vehicle crash during the study period. Direct costs for each case and control were estimated in 2013 Canadian dollars from the payer perspective using methodology that links health care use to individuals over time. We calculated costs attributable to motorcycle and automobile crashes within 2 years using a difference-in-differences approach. RESULTS: We identified 26 831 patients injured in motorcycle crashes and 281 826 injured in automobile crashes. Mean costs attributable to motorcycle and automobile crashes were $5825 and $2995, respectively (p < 0.001). The rate of injury was triple for motorcycle crashes compared with automobile crashes (2194 injured annually/100 000 registered motorcycles v. 718 injured annually/100 000 registered automobiles; incidence rate ratio [IRR] 3.1, 95% confidence interval [CI] 2.8 to 3.3, p < 0.001). Severe injuries, defined as those with an Abbreviated Injury Scale ≥ 3, were 10 times greater (125 severe injuries annually/100 000 registered motorcycles v. 12 severe injuries annually/100 000 registered automobiles; IRR 10.4, 95% CI 8.3 to 13.1, p < 0.001). INTERPRETATION: Considering both the attributable cost and higher rate of injury, we found that each registered motorcycle in Ontario costs the public health care system 6 times the amount of each registered automobile. Medical costs may provide an additional incentive to improve motorcycle safety. PMID:29158454
Chen, Cong; Zhang, Guohui; Huang, Helai; Wang, Jiangfeng; Tarefder, Rafiqul A
2016-11-01
Rural non-interstate crashes induce a significant amount of severe injuries and fatalities. Examination of such injury patterns and the associated contributing factors is of practical importance. Taking into account the ordinal nature of injury severity levels and the hierarchical feature of crash data, this study employs a hierarchical ordered logit model to examine the significant factors in predicting driver injury severities in rural non-interstate crashes based on two-year New Mexico crash records. Bayesian inference is utilized in model estimation procedure and 95% Bayesian Credible Interval (BCI) is applied to testing variable significance. An ordinary ordered logit model omitting the between-crash variance effect is evaluated as well for model performance comparison. Results indicate that the model employed in this study outperforms ordinary ordered logit model in model fit and parameter estimation. Variables regarding crash features, environment conditions, and driver and vehicle characteristics are found to have significant influence on the predictions of driver injury severities in rural non-interstate crashes. Factors such as road segments far from intersection, wet road surface condition, collision with animals, heavy vehicle drivers, male drivers and driver seatbelt used tend to induce less severe driver injury outcomes than the factors such as multiple-vehicle crashes, severe vehicle damage in a crash, motorcyclists, females, senior drivers, driver with alcohol or drug impairment, and other major collision types. Research limitations regarding crash data and model assumptions are also discussed. Overall, this research provides reasonable results and insight in developing effective road safety measures for crash injury severity reduction and prevention. Copyright © 2016 Elsevier Ltd. All rights reserved.
Wrong-way driving crashes on French divided roads.
Kemel, Emmanuel
2015-02-01
The objective of divided roads is to increase users' safety by posting unidirectional traffic flows. It happens however that drivers proceed in the wrong direction, endangering themselves as well as other users. The crashes caused by wrong-way drivers are generally spotlighted by the media and call for public intervention. This paper proposes a characterization of wrong-way driving crashes occurring on French divided road on the 2008-2012 period. The objective is to identify the factors that delineate between wrong-way driving crashes and other crashes. Building on the national injury road crash database, 266 crashes involving a wrong-way driver were identified. Their characteristics (related to timing, location, vehicle and driver) are compared to those of the 22,120 other crashes that occurred on the same roads over the same period. The comparison relies on descriptive statistics, completed by a logistic regression. Wrong-way driving crashes are rare but severe. They are more likely to occur during night hours and on non-freeway roads than other crashes. Wrong-way drivers are older, more likely to be intoxicated, to be locals, to drive older vehicles, mainly passenger cars without passengers, than other drivers. The differences observed across networks can help prioritizing public intervention. Most of the identified WW-driving factors deal with cognitive impairment. Therefore, the specific countermeasures such as alternative road signs should be designed for and tested on cognitively impaired drivers. Nevertheless, WW-driving factors are also risk factors for other types of crashes (e.g. elderly driving, drunk driving and age of the vehicle). This suggests that, instead of (or in addition to) developing WW-driving specific countermeasures, managing these risk factors would help reducing a larger number of crashes. Copyright © 2014 Elsevier Ltd. All rights reserved.
Crash-resistant fuel system effectiveness in civil helicopter crashes.
Hayden, Mark S; Shanahan, Dennis F; Chen, Li-Hui; Baker, Susan P
2005-08-01
Crash-resistant fuel systems (CRFS) have demonstrated close to 100% effectiveness in survivable crashes of Army helicopters, but the technology has been slow to transfer into the civil helicopter arena. Federal standards for civil helicopter CRFS are less stringent than those for military helicopters. A reduction in standards for CRFS in military helicopters is being considered. The goal of this study was to determine whether crashes of civil helicopters with CRFS are less likely to result in post-crash fire than crashes of those without. Crashes of civil helicopters during 1982-2004 were analyzed, comparing Bell 206 helicopters manufactured with CRFS with Aerospatial 350 helicopters manufactured during the same period (post-1981), but lacking CRFS. Bell 206 helicopters with CRFS were also compared with earlier models without CRFS. The highest proportion of crashes with post-crash fires (11.3%) was in AS-350s manufactured after 1981 (non-CRFS), and the lowest (3.7%) was in Bell 206s (with CRFS) [unadjusted risk ratio (RR) = 3.3, 95% confidence interval (CI) = 1.04, 10.50; adjusted for light and weather, RR = 2.81, Cl = 0.82, 9.69]. Earlier models of Bell 206s without CRFS had higher risk of post-crash fire than post-1981 models with CRFS (7.4% vs. 3.7%; adjusted RR = 2.11, Cl = 0.82, 5.45). The results of this study suggest a better performance, in terms of post-crash fire prevention, of CRFS-equipped civil helicopters as compared with those without CRFS. It is possible that CRFS in civil helicopters have not achieved the same degree of effectiveness as CRFS in military helicopters. CRFS should be used more widely in civil helicopters. The more stringent CRFS requirements for military helicopters should not be reduced without further research.
Crash test ratings and real-world frontal crash outcomes: a CIREN study.
Ryb, Gabriel E; Burch, Cynthia; Kerns, Timothy; Dischinger, Patricia C; Ho, Shiu
2010-05-01
To establish whether the Insurance Institute for Highway Safety (IIHS) offset crash test ratings are linked to different mortality rates in real world frontal crashes. The study used Crash Injury Research Engineering Network drivers of age older than 15 years who were involved in frontal crashes. The Crash Injury Research Engineering Network is a convenience sample of persons injured in crashes with at least one Abbreviated Injury Scale score of 3+ injury or two Abbreviated Injury Scale score of 2+ injuries who were either treated at a Level I trauma center or died. Cases were grouped by IIHS crash test ratings (i.e., good, acceptable, marginal, poor, and not rated). Those rated marginal were excluded because of their small numbers. Mortality rates experienced by these ratings-based groups were compared using the Mantel-Haenszel chi test. Multiple logistic regression models were built to adjust for confounders (i.e., occupant, vehicular, and crash factors). A total of 1,226 cases were distributed within not rated (59%), poor (12%), average (16%), and good (14%) categories. Those rated good and average experienced a lower unadjusted mortality rate. After adjustment by confounders, those in vehicles rated good experienced a lower risk of death (adjusted OR 0.38 [0.16-0.90]) than those in vehicles rated poor. There was no significant effect for "acceptable" rating. Other factors influencing the occurrence of death were age, DeltaV >or=70 km/h, high body mass index, and lack of restraint use. After adjusting for occupant, vehicular, and crash factors, drivers of vehicles rated good by the IIHS experienced a lower risk of death in frontal crashes.
Zhao, Peibo; Lee, Chris
2018-04-01
This study analyzes rear-end collision risk of cars and heavy vehicles on freeways using a surrogate safety measure. The crash potential index (CPI) was modified to reflect driver's reaction time and estimated by types of lead and following vehicles (car or heavy vehicle). CPIs were estimated using the individual vehicle trajectory data from a segment of the US-101 freeway in Los Angeles, U.S.A. It was found that the CPI was generally higher for the following heavy vehicle than the following car due to heavy vehicle's lower braking capability. This study also validates the CPI using the simulated traffic data which replicate the observed traffic conditions a few minutes before the crash time upstream and downstream of the crash locations. The observed data were obtained from crash records and loop detectors on a section of the Gardiner Expressway in Toronto, Canada. The result shows that the values of CPI were consistently higher during the traffic conditions immediately before the crash time (crash case) than the normal traffic conditions (non-crash case). This demonstrates that the CPI can be used to capture rear-end collision risk during car-following maneuver on freeways. The result also shows that rear-end collision risk is lower for heavy vehicles than cars in the crash case due to their shorter reaction time and lower speed when spacing is shorter. Thus, it is important to reflect the differences in driver behavior and vehicle performance characteristics between cars and heavy vehicles in estimating surrogate safety measures. Lastly, it was found that the CPI-based crash prediction model can correctly identify the crash and non-crash cases at higher accuracy than the other crash prediction models based on detectors. Copyright © 2018 Elsevier Ltd. All rights reserved.
Opportunities for crash and injury reduction: A multiharm approach for crash data analysis.
Mallory, Ann; Kender, Allison; Moorhouse, Kevin
2017-05-29
A multiharm approach for analyzing crash and injury data was developed for the ultimate purpose of getting a richer picture of motor vehicle crash outcomes for identifying research opportunities in crash safety. Methods were illustrated using a retrospective analysis of 69,597 occupant cases from NASS CDS from 2005 to 2015. Occupant cases were analyzed by frequency and severity of outcome: fatality, injury by Abbreviated Injury Scale (AIS), number of cases, attributable fatality, disability, and injury costs. Comparative analysis variables included precrash scenario, impact type, and injured body region. Crash and injury prevention opportunities vary depending on the search parameters. For example, occupants in rear-end crash scenarios were more frequent than in any other precrash configuration, yet there were significantly more fatalities and serious injury cases in control loss, road departure, and opposite direction crashes. Fatality is most frequently associated with head and thorax injury, and disability is primarily associated with extremity injury. Costs attributed to specific body regions are more evenly distributed, dominated by injuries to the head, thorax, and extremities but with contributions from all body regions. Though AIS 3+ can be used as a single measure of harm, an analysis based on multiple measures of harm gives a much more detailed picture of the risk presented by a particular injury or set of crash conditions. The developed methods represent a new approach to crash data mining that is expected to be useful for the identification of research priorities and opportunities for reduction of crashes and injuries. As the pace of crash safety improvement accelerates with innovations in both active and passive safety, these techniques for combining outcome measures for insights beyond fatality and serious injury will be increasingly valuable.
Sorock, G S; Ranney, T A; Lehto, M R
1996-01-01
Motor vehicle travel through roadway construction workzones has been shown to increase the risk of a crash. The number of workzones has increased due to recent congressional funding in 1991 for expanded roadway maintenance and repair. In this paper, we describe the characteristics and costs of motor vehicle crashes in roadway construction workzones. As opposed to using standard accident codes to identify accident types, automobile insurance claims files from 1990-93 were searched to identify records with the keyword "construction" in the accident narrative field. A total of 3,686 claims were used for the analysis of crashes. Keywords from the accident narrative field were used to identify five pre-crash vehicle activities and five crash types. We evaluated misclassification error by reading 560 randomly selected claims and found it to be only 5%. For each of four years, 1990-93, there was a total of 648,996,977 and 1,065 crashes, respectively. There was a 70% increase in the crash rate per 10,000 personal insured vehicles from 1990-93 (2.1-3.6). Most crashes (26%) involved a stopped or slowing vehicle in the workzone. The most common crash (31%) was a rear-end collision. The most costly pre-crash activity was a major judgment error on the part of a driver (n = 120, median cost = $2,628). An overturned vehicle was the most costly crash type (n = 16, median cost = $4,745). In summary, keyword text analysis of accident narrative data used in this study demonstrated its utility and potential for enhancing injury epidemiology. The results suggest interventions are needed to respond to growing traffic hazards in construction workzones.
NASA Astrophysics Data System (ADS)
Deviren, Bayram; Kocakaplan, Yusuf; Keskin, Mustafa; Balcılar, Mehmet; Özdemir, Zeynel Abidin; Ersoy, Ersan
2014-09-01
In this study, we analyze the Turkish Lira/US Dollar (TRY/USD), Turkish Lira/Euro (TRY/EUR), Turkish Lira/Japanese Yen (TRY/JPY) and Turkish Lira/Swiss Franc (TRY/CHF) exchange rates in the global financial crisis period to detect the bubbles and crashes in the TRY by using a mathematical methodology developed by Watanabe et al. (2007). The methodology defines the bubbles and crashes in financial market price fluctuations by considering an exponential fitting of the associated data. This methodology is applied to detect the bubbles and crashes in the TRY/USD, TRY/EUR, TRY/JPY and TRY/CHF exchange rates from January, 1, 2005 to December, 20, 2013. In this mathematical methodology, the whole period of bubbles and crashes can be determined purely from past data, and the start of bubbles and crashes can be identified even before its bursts. In this way, the periods of bubbles and crashes in the TRY/USD, TRY/EUR, TRY/JPY and TRY/CHF are determined, and the beginning and end points of these periods are detected. The results show that the crashes in the TRY/CHF exchange rate are commonly finished earlier than in the other exchange rates; hence it is probable that the crashes in the other exchange rates would be finished soon when the crashes in the TRY/CHF exchange rate ended. We also find that the periods of crashes in the TRY/EUR exchange rate take longer time than in the other exchange rates. This information can be used in risk management and/or speculative gain. The crashes' periods in the TRY/EUR and TRY/USD exchange rates are observed to be relatively longer than in the other exchange rates.
Ignition Interlock Laws: Effects on Fatal Motor Vehicle Crashes, 1982-2013.
McGinty, Emma E; Tung, Gregory; Shulman-Laniel, Juliana; Hardy, Rose; Rutkow, Lainie; Frattaroli, Shannon; Vernick, Jon S
2017-04-01
Alcohol-involved motor vehicle crashes are a major cause of preventable mortality in the U.S., leading to more than 10,000 fatalities in 2013. Ignition interlocks, or alcohol-sensing devices connected to a vehicle's ignition to prevent it from starting if a driver has a predetermined blood alcohol content (BAC) level, are a promising avenue for preventing alcohol-involved driving. This study sought to assess the effects of laws requiring ignition interlocks for some or all drunk driving offenders on alcohol-involved fatal crashes. A multilevel modeling approach assessed the effects of state interlock laws on alcohol-involved fatal crashes in the U.S. from 1982 to 2013. Monthly data on alcohol-involved crashes in each of the 50 states was collected in 2014 from the National Highway Traffic Safety Administration Fatality Analysis Reporting System. Random-intercept models accounted for between-state variation in alcohol-involved fatal crash rates and autocorrelation of within-state crash rates over time. Analysis was conducted in 2015. State laws requiring interlocks for all drunk driving offenders were associated with a 7% decrease in the rate of BAC >0.08 fatal crashes and an 8% decrease in the rate of BAC ≥0.15 fatal crashes, translating into an estimated 1,250 prevented BAC >0.08 fatal crashes. Laws requiring interlocks for segments of high-risk drunk driving offenders, such as repeat offenders, may reduce alcohol-involved fatal crashes after 2 years of implementation. Ignition interlock laws reduce alcohol-involved fatal crashes. Increasing the spread of interlock laws that are mandatory for all offenders would have significant public health benefit. Copyright © 2016 American Journal of Preventive Medicine. All rights reserved.
Vanlaar, Ward; Robertson, Robyn; Marcoux, Kyla
2014-01-01
The objective of this study was to evaluate the impact of Winnipeg's photo enforcement safety program on speeding, i.e., "speed on green", and red-light running behavior at intersections as well as on crashes resulting from these behaviors. ARIMA time series analyses regarding crashes related to red-light running (right-angle crashes and rear-end crashes) and crashes related to speeding (injury crashes and property damage only crashes) occurring at intersections were conducted using monthly crash counts from 1994 to 2008. A quasi-experimental intersection camera experiment was also conducted using roadside data on speeding and red-light running behavior at intersections. These data were analyzed using logistic regression analysis. The time series analyses showed that for crashes related to red-light running, there had been a 46% decrease in right-angle crashes at camera intersections, but that there had also been an initial 42% increase in rear-end crashes. For crashes related to speeding, analyses revealed that the installation of cameras was not associated with increases or decreases in crashes. Results of the intersection camera experiment show that there were significantly fewer red light running violations at intersections after installation of cameras and that photo enforcement had a protective effect on speeding behavior at intersections. However, the data also suggest photo enforcement may be less effective in preventing serious speeding violations at intersections. Overall, Winnipeg's photo enforcement safety program had a positive net effect on traffic safety. Results from both the ARIMA time series and the quasi-experimental design corroborate one another. However, the protective effect of photo enforcement is not equally pronounced across different conditions so further monitoring is required to improve the delivery of this measure. Results from this study as well as limitations are discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.
Landscaping of highway medians and roadway safety at unsignalized intersections.
Chen, Hongyun; Fabregas, Aldo; Lin, Pei-Sung
2016-05-01
Well-planted and maintained landscaping can help reduce driving stress, provide better visual quality, and decrease over speeding, thus improving roadway safety. Florida Department of Transportation (FDOT) Standard Index (SI-546) is one of the more demanding standards in the U.S. for landscaping design criteria at highway medians near intersections. The purposes of this study were to (1) empirically evaluate the safety results of SI-546 at unsignalized intersections and (2) quantify the impacts of geometrics, traffic, and landscaping design features on total crashes and injury plus fatal crashes. The studied unsignalized intersections were divided into (1) those without median trees near intersections, (2) those with median trees near intersections that were compliant with SI-546, and (3) those with median trees near intersections that were non-compliant with SI-546. A total of 72 intersections were selected, for which five-year crash data from 2006-2010 were collected. The sites that were compliant with SI-546 showed the best safety performance in terms of the lowest crash counts and crash rates. Four crash predictive models-two for total crashes and two for injury crashes-were developed. The results indicated that improperly planted and maintained median trees near highway intersections can increase the total number of crashes and injury plus fatal crashes at a 90% confidence level; no significant difference could be found in crash rates between sites that were compliant with SI-546 and sites without trees. All other conditions remaining the same, an intersection with trees that was not compliant with SI-546 had 63% more crashes and almost doubled injury plus fatal crashes than those at intersections without trees. The study indicates that appropriate landscaping in highway medians near intersections can be an engineering technology that not only improves roadway environmental quality but also maintains intersection safety. Copyright © 2016. Published by Elsevier Ltd.
Statistical Characteristics of Wrong-Way Driving Crashes on Illinois Freeways.
Zhou, Huaguo; Zhao, Jiguang; Pour-Rouholamin, Mahdi; Tobias, Priscilla A
2015-01-01
Driving the wrong way on freeways, namely wrong-way driving (WWD), has been found to be a major concern for more than 6 decades. The purpose of this study was to identify characteristics of this type of crash as well as to rank the locations/interchanges according to their vulnerability to WWD entries. The WWD crash data on Illinois freeways were statistically analyzed for a 6-year time period (2004 to 2009) from 3 aspects: crash, vehicle, and person. The temporal distributions, geographical distributions, roadway characteristics, and crash locations were analyzed for WWD crashes. The driver demographic information, physical condition, and injury severity were analyzed for wrong-way drivers. The vehicle characteristics, vehicle operation, and collision results were analyzed for WWD vehicles. A method was brought about to identify wrong-way entry points that was then used to develop a relative-importance technique and rank different interchange types in terms of potential WWD incidents. The findings revealed that a large proportion of WWD crashes occurred during the weekend from midnight to 5 a.m. Approximately 80% of WWD crashes were located in urban areas and nearly 70% of wrong-way vehicles were passenger cars. Approximately 58% of wrong-way drivers were driving under the influence (DUI). Of those, nearly 50% were confirmed to be impaired by alcohol, about 4% were impaired by drugs, and more than 3% had been drinking. The analysis of interchange ranking found that compressed diamond interchanges, single point diamond interchanges (SPDIs), partial cloverleaf interchanges, and freeway feeders had the highest wrong-way crash rates (wrong-way crashes per 100 interchanges per year). The findings of this study call for more attention to WWD crashes from different aspects such as driver age group, time of day, day of week, and DUI drivers. Based on the analysis results of WWD distance, the study explained why a 5-mile radius of WWD crash location should be studied for WWD fatal crashes with unknown entry points.
Consideration of driver home county prohibition and alcohol-related vehicle crashes.
Schulte Gary, Sarah Lynn; Aultman-Hall, Lisa; McCourt, Matt; Stamatiadis, Nick
2003-09-01
This study examines the characteristics of alcohol-related crashes in wet versus dry counties in the state of Kentucky, USA and incorporates the location of driver residences through use of geographic information system (GIS) analysis. Between 1991 and 1997, 39344 alcohol-related crashes by Kentucky residents on Kentucky State roads were reported. The location of the crash and the home ZIP code from the driver's address were used to consider distance from home in the GIS. Analysis of the crash data revealed that a similar proportion of crashes in wet and dry counties are alcohol-related but that a higher proportion of dry counties residents are involved in an alcohol-related crash. However, when the distance from home variable is considered, several results suggest that dry county residents may be driving further when consuming alcohol. In part due to the rural nature of dry counties, drivers from dry counties have both alcohol-related and non-alcohol related crashes farther from their homes than residents from wet counties. Alcohol-related crashes by dry county residents in wet counties are the greatest average distance from home while crashes by wet county residents in wet counties are the smallest average distance. Drivers from dry counties over 21 years of age have alcohol-related crashes significantly farther from home than those under 21 who would not legally be admitted to drinking establishments in the wet counties. Furthermore, residents from dry counties that do not border wet counties have alcohol-related crashes on average farther from home than the border county residents. These last three results provide circumstantial evidence that some dry county drivers may be driving to wet counties to consume alcohol thus increasing impaired driving exposure. In conclusion, by considering crash location and driver residence, these findings indicate that county-level prohibition is not necessarily effective in improving highway safety.
Front air bag nondeployments in frontal crashes fatal to drivers or right-front passengers.
Braver, Elisa R; McCartt, Anne T; Sherwood, Christopher P; Zuby, David S; Blanar, Laura; Scerbo, Marge
2010-04-01
Public concern has arisen about the reliability of front air bags because Fatality Analysis Reporting System (FARS) data indicate many nondeployed air bags in fatal frontal crashes. However, the accuracy of air bag deployment, the variable in question, is uncertain. This study aimed to provide more certain estimates of nondeployment incidence in fatal frontal crashes. Fatally injured passenger vehicle drivers and right-front passengers in frontal crashes were identified in two U.S. databases for calendar years 1998-2006 and model years 1994-2006: FARS, a census of police-reported fatal crashes on public roads, and National Automotive Sampling System/Crashworthiness Data System (NASS/CDS), a probability sample of tow-away crashes. NASS/CDS contains subsets of fatal crashes in FARS and collects detailed data using crash investigators. Front air bag deployment coding for front-seat occupant fatalities was compared in FARS and NASS/CDS, and case reviews were conducted. Among FARS frontal deaths with available deployment status (N = 43,169), front air bags were coded as not deployed for 18 percent of front occupants. In comparison, NASS/CDS (N = 628) reported 9 percent (weighted estimate) nondeployment among front occupants killed. Among crashes common to both databases, NASS/CDS reported deployments for 45 percent of front occupant deaths for which FARS had coded nondeployments. Detailed case reviews of NASS/CDS crashes indicated highly accurate coding for deployment status. Based on this case review, 8 percent (weighted estimate) of front occupant deaths in frontal crashes appeared to involve air bag nondeployments; 1-2 percent of front occupant deaths represented potential system failures where deployments would have been expected. Air bag deployments appeared unwarranted in most nondeployments based on crash characteristics. FARS data overstate the magnitude of the problem of air bag deployment failures; steps should be taken to improve coding. There are inherent uncertainties in judgments about whether or not air bags would be expected to deploy in some crashes. Continued monitoring of air bag performance is warranted.
Curry, Allison E.; Pfeiffer, Melissa R.; Myers, Rachel K.; Durbin, Dennis R.; Elliott, Michael R.
2014-01-01
Traditional methods for determining crash responsibility—most commonly moving violation citations—may not accurately characterize at-fault status among crash-involved drivers given that: (1) issuance may vary by factors that are independent of fault (e.g., driver age, gender), and (2) these methods do not capture driver behaviors that are not illegal but still indicative of fault. We examined the statistical implications of using moving violations to determine crash responsibility in young driver crashes by comparing it with a method based on crash-contributing driver actions. We selected all drivers in police-reported passenger-vehicle crashes (2010–2011) that involved a New Jersey driver <21 years old (79,485 drivers < age 21, 61,355 drivers ≥ age 21.) For each driver, crash responsibility was determined from the crash report using two alternative methods: (1) issuance of a moving violation citation; and (2) presence of a driver action (e.g., failure to yield, inattention). Overall, 18% of crash-involved drivers were issued a moving violation while 50% had a driver action. Only 32.2% of drivers with a driver action were cited for a moving violation. Further, the likelihood of being cited given the presence of a driver action was higher among certain driver subgroups—younger drivers, male drivers, and drivers in single-vehicle and more severe crashes. Specifically among young drivers, those driving at night, carrying peer passengers, and having a suspended or no license were more often cited. Conversely, fatally-injured drivers were almost never cited. We also demonstrated that using citation data may lead to statistical bias in the characterization of at-fault drivers and of quasi-induced exposure measures. Studies seeking to accurately determine crash responsibility should thoughtfully consider the potential sources of bias that may result from using legal culpability methods. For many studies, determining driver responsibility via the identification of driver actions may yield more accurate characterizations of at-fault drivers. PMID:24398139
Kaplan, Sigal; Prato, Carlo Giacomo
2012-01-01
The current study focuses on the propensity of drivers to engage in crash avoidance maneuvers in relation to driver attributes, critical events, crash characteristics, vehicles involved, road characteristics, and environmental conditions. The importance of avoidance maneuvers derives from the key role of proactive and state-aware road users within the concept of sustainable safety systems, as well as from the key role of effective corrective maneuvers in the success of automated in-vehicle warning and driver assistance systems. The analysis is conducted by means of a mixed logit model that represents the selection among 5 emergency lateral and speed control maneuvers (i.e., "no avoidance maneuvers," "braking," "steering," "braking and steering," and "other maneuvers) while accommodating correlations across maneuvers and heteroscedasticity. Data for the analysis were retrieved from the General Estimates System (GES) crash database for the year 2009 by considering drivers for which crash avoidance maneuvers are known. The results show that (1) the nature of the critical event that made the crash imminent greatly influences the choice of crash avoidance maneuvers, (2) women and elderly have a relatively lower propensity to conduct crash avoidance maneuvers, (3) drowsiness and fatigue have a greater negative marginal effect on the tendency to engage in crash avoidance maneuvers than alcohol and drug consumption, (4) difficult road conditions increase the propensity to perform crash avoidance maneuvers, and (5) visual obstruction and artificial illumination decrease the probability to carry out crash avoidance maneuvers. The results emphasize the need for public awareness campaigns to promote safe driving style for senior drivers and warning about the risks of driving under fatigue and distraction being comparable to the risks of driving under the influence of alcohol and drugs. Moreover, the results suggest the need to educate drivers about hazard perception, designing a forgiving infrastructure within a sustainable safety systems, and rethinking in-vehicle collision warning systems. Future research should address the effectiveness of crash avoidance maneuvers and joint modeling of maneuver selection and crash severity.
Graduated licensing laws and fatal crashes of teenage drivers: a national study.
McCartt, Anne T; Teoh, Eric R; Fields, Michele; Braitman, Keli A; Hellinga, Laurie A
2010-06-01
The objective of the current study was to quantify the effects of the strength of US state graduated driver licensing laws and specific licensing components on the rate of teenage driver fatal crash involvements per 100,000 teenagers during 1996-2007. The strengths of state laws were rated good, fair, marginal, or poor based on a system developed previously by the Insurance Institute for Highway Safety. Analysis was based on quarterly counts of drivers involved in fatal crashes. Associations of overall ratings and individual licensing components with teenage crash rates were evaluated using Poisson regression, with the corresponding fatal crash rate for drivers ages 30-59 controlling for state- or time-dependent influences on crash rates unrelated to graduated licensing laws. Compared with licensing laws rated poor, laws rated good were associated with 30 percent lower fatal crash rates among 15- to 17-year-olds. Laws rated fair yielded fatal crash rates 11 percent lower. The longer the permit age was delayed, or the longer the licensing age was delayed, the lower the estimated fatal crash rates among 15- to 17-year-olds. Stronger nighttime restrictions were associated with larger reductions, and reductions were larger for laws limiting teenage passengers to zero or one than laws allowing two or more teenage passengers or laws without passenger restrictions. After the effects of any related delay in licensure were accounted for, an increase in the minimum learner's permit holding period showed no association with fatal crash rates. An increase in required practice driving hours did not appear to have an independent association with fatal crash rates. Graduated licensing laws that include strong nighttime and passenger restrictions and laws that delay the learner's permit age and licensing age are associated with lower teenage fatal crash rates. States that adopt such laws can expect to achieve substantial reductions in crash deaths.
Fatal crashes involving large trucks, 2015 : analysis brief.
DOT National Transportation Integrated Search
2017-04-01
In 2015, 32,166 fatal crashes took place on our Nations roadways, with 11.2 percent (3,598) involving at least one large truck (see Figure 1). This report examines the various ways of looking at fatal crashes and presents a variety of crash rates ...
Developing Louisiana crash reduction factors : [tech summary].
DOT National Transportation Integrated Search
2013-10-01
Although, like the rest of the country, Louisiana has made great strides in reducing the number of crashes, particularly : fatal crashes, in recent years, our fatal crash rate of 1.56 is still higher than the national average of 1.10 in 2010. The vis...
Driver-related factors in crashes between large trucks and passenger vehicles
DOT National Transportation Integrated Search
1999-04-01
Large trucks are involved in close to 400,000 police-reported crashes each year, of which 4,500 involve a fatality. About 60% of fatal truck crashes involve one large truck colliding with a single passenger vehicle. Prevention of these crashes requir...
Comparing countermeasures for mitigating wrong-way entries onto limited access facilities.
DOT National Transportation Integrated Search
2017-03-01
Wrong-way crashes are a major cause for safety concerns along freeways and limited-access facilities. Although wrong-way crashes account for a relatively small portion of total crashes, the impact between two cars crashing into each other at high spe...
Investigation of the Performance of Safety Systems for Protection of the Elderly
Augenstein, J.; Digges, K; Bahouth, G.; Dalmotas, D.; Perdeck, E.; Stratton, J.
2005-01-01
This study investigates injury occurrence for belted occupants as a function of age. An analysis of NASS/CDS 1997–2003 data was conducted to determine crash involvement rates and injury rates for front seat occupants versus mean occupant age. In frontal and near-side crashes, the average age of MAIS 3+ belted front seat occupants injured in crashes less severe than 15 mph is of the order of 50 years. The average age of the population exposed to crashes less severe than 15 mph is under 40 years old. The crash exposure and frequency if injuries to the elderly were both found to be the highest in low severity crashes. The chest is the most frequent body region injured for the elderly. These findings suggest the need for more benign safety systems to protect the elderly in low severity crashes. Design of safety systems for the elderly should give priority to reducing the chest loading in low severity frontal and near-side crashes. PMID:16179159
Distracted Driving and Risk of Road Crashes among Novice and Experienced Drivers
Klauer, Sheila G.; Guo, Feng; Simons-Morton, Bruce G.; Ouimet, Marie Claude; Lee, Suzanne E.; Dingus, Thomas A.
2014-01-01
BACKGROUND Distracted driving attributable to the performance of secondary tasks is a major cause of motor vehicle crashes both among teenagers who are novice drivers and among adults who are experienced drivers. METHODS We conducted two studies on the relationship between the performance of secondary tasks, including cell-phone use, and the risk of crashes and near-crashes. To facilitate objective assessment, accelerometers, cameras, global positioning systems, and other sensors were installed in the vehicles of 42 newly licensed drivers (16.3 to 17.0 years of age) and 109 adults with more driving experience. RESULTS During the study periods, 167 crashes and near-crashes among novice drivers and 518 crashes and near-crashes among experienced drivers were identified. The risk of a crash or near-crash among novice drivers increased significantly if they were dialing a cell phone (odds ratio, 8.32; 95% confidence interval [CI], 2.83 to 24.42), reaching for a cell phone (odds ratio, 7.05; 95% CI, 2.64 to 18.83), sending or receiving text messages (odds ratio, 3.87; 95% CI, 1.62 to 9.25), reaching for an object other than a cell phone (odds ratio, 8.00; 95% CI, 3.67 to 17.50), looking at a roadside object (odds ratio, 3.90; 95% CI, 1.72 to 8.81), or eating (odds ratio, 2.99; 95% CI, 1.30 to 6.91). Among experienced drivers, dialing a cell phone was associated with a significantly increased risk of a crash or near-crash (odds ratio, 2.49; 95% CI, 1.38 to 4.54); the risk associated with texting or accessing the Internet was not assessed in this population. The prevalence of high-risk attention to secondary tasks increased over time among novice drivers but not among experienced drivers. CONCLUSIONS The risk of a crash or near-crash among novice drivers increased with the performance of many secondary tasks, including texting and dialing cell phones. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development and the National Highway Traffic Safety Administration.) PMID:24382065
Comprehensive target populations for current active safety systems using national crash databases.
Kusano, Kristofer D; Gabler, Hampton C
2014-01-01
The objective of active safety systems is to prevent or mitigate collisions. A critical component in the design of active safety systems is the identification of the target population for a proposed system. The target population for an active safety system is that set of crashes that a proposed system could prevent or mitigate. Target crashes have scenarios in which the sensors and algorithms would likely activate. For example, the rear-end crash scenario, where the front of one vehicle contacts another vehicle traveling in the same direction and in the same lane as the striking vehicle, is one scenario for which forward collision warning (FCW) would be most effective in mitigating or preventing. This article presents a novel set of precrash scenarios based on coded variables from NHTSA's nationally representative crash databases in the United States. Using 4 databases (National Automotive Sampling System-General Estimates System [NASS-GES], NASS Crashworthiness Data System [NASS-CDS], Fatality Analysis Reporting System [FARS], and National Motor Vehicle Crash Causation Survey [NMVCCS]) the scenarios developed in this study can be used to quantify the number of police-reported crashes, seriously injured occupants, and fatalities that are applicable to proposed active safety systems. In this article, we use the precrash scenarios to identify the target populations for FCW, pedestrian crash avoidance systems (PCAS), lane departure warning (LDW), and vehicle-to-vehicle (V2V) or vehicle-to-infrastructure (V2I) systems. Crash scenarios were derived using precrash variables (critical event, accident type, precrash movement) present in all 4 data sources. This study found that these active safety systems could potentially mitigate approximately 1 in 5 of all severity and serious injury crashes in the United States and 26 percent of fatal crashes. Annually, this corresponds to 1.2 million all severity, 14,353 serious injury (MAIS 3+), and 7412 fatal crashes. In addition, we provide the source code for the crash scenarios as an appendix (see online supplement) to this article so that researchers can use the crash scenarios in future research.
Vorona, Robert Daniel; Szklo-Coxe, Mariana; Lamichhane, Rajan; Ware, J. Catesby; McNallen, Ann; Leszczyszyn, David
2014-01-01
Background and Objective: Early high school start times (EHSST) may lead to sleep loss in adolescents (“teens”), thus resulting in higher crash rates. (Vorona et al., 2011). In this study, we examined two other adjacent Virginia counties for the two years subsequent to the above-mentioned study. We again hypothesized that teens from jurisdictions with EHSST (versus later) experience higher crash rates. Methods: Virginia Department of Motor Vehicles supplied de-identified aggregate data on weekday crashes and time-of-day for 16-18 year old (teen) and adult drivers for school years 2009-2010 and 2010-2011 in Henrico and Chesterfield Counties (HC and CC, respectively). Teen crash rates for counties with early (CC) versus later (HC) school start-times were compared using two-sample Z-tests and these compared to adult crash rates using pair-wise tests. Results: Chesterfield teens manifested a statistically higher crash rate of 48.8/1,000 licensed drivers versus Henrico's 37.9/1,000 (p = 0.04) for 2009-2010. For 2010-2011, CC 16-17 year old teens demonstrated a statistically significant higher crash rate (53.2/1,000 versus 42.0/1,000), while for 16-18 teens a similar trend was found, albeit nonsignificant (p = 0.09). Crash peaks occurred 1 hour earlier in the morning and 2 hours earlier in the afternoon in Chesterfield, consistent with commute times. Post hoc analyses found significantly more run-off road crashes to the right (potentially sleep-related) in Chesterfield teens. Adult crash rates and traffic congestion did not differ between counties. Conclusions: Higher teen crash rates occurred in jurisdictions with EHSST, as in our prior study. This study contributes to and extends existing data on preventable teen crashes and high school start times. Citation: Vorona RD, Szklo-Coxe M, Lamichhane R, Ware JC, McNallen A, Leszczyszyn D. Adolescent crash rates and school start times in two central Virginia counties, 2009-2011: a follow-up study to a southeastern Virginia study, 2007-2008. J Clin Sleep Med 2014;10(11):1169-1177. PMID:25325600
Distracted driving and risk of road crashes among novice and experienced drivers.
Klauer, Sheila G; Guo, Feng; Simons-Morton, Bruce G; Ouimet, Marie Claude; Lee, Suzanne E; Dingus, Thomas A
2014-01-02
Distracted driving attributable to the performance of secondary tasks is a major cause of motor vehicle crashes both among teenagers who are novice drivers and among adults who are experienced drivers. We conducted two studies on the relationship between the performance of secondary tasks, including cell-phone use, and the risk of crashes and near-crashes. To facilitate objective assessment, accelerometers, cameras, global positioning systems, and other sensors were installed in the vehicles of 42 newly licensed drivers (16.3 to 17.0 years of age) and 109 adults with more driving experience. During the study periods, 167 crashes and near-crashes among novice drivers and 518 crashes and near-crashes among experienced drivers were identified. The risk of a crash or near-crash among novice drivers increased significantly if they were dialing a cell phone (odds ratio, 8.32; 95% confidence interval [CI], 2.83 to 24.42), reaching for a cell phone (odds ratio, 7.05; 95% CI, 2.64 to 18.83), sending or receiving text messages (odds ratio, 3.87; 95% CI, 1.62 to 9.25), reaching for an object other than a cell phone (odds ratio, 8.00; 95% CI, 3.67 to 17.50), looking at a roadside object (odds ratio, 3.90; 95% CI, 1.72 to 8.81), or eating (odds ratio, 2.99; 95% CI, 1.30 to 6.91). Among experienced drivers, dialing a cell phone was associated with a significantly increased risk of a crash or near-crash (odds ratio, 2.49; 95% CI, 1.38 to 4.54); the risk associated with texting or accessing the Internet was not assessed in this population. The prevalence of high-risk attention to secondary tasks increased over time among novice drivers but not among experienced drivers. The risk of a crash or near-crash among novice drivers increased with the performance of many secondary tasks, including texting and dialing cell phones. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development and the National Highway Traffic Safety Administration.).
Effect of vehicular size on chain-reaction crash
NASA Astrophysics Data System (ADS)
Nagatani, Takashi
2015-11-01
We present the dynamic model of the chain-reaction crash to take account of the vehicular size. Drivers brake according to taillights of the forward vehicle. We investigate the effect of the vehicular size on the chain-reaction crash (multiple-vehicle collision) in the traffic flow controlled by taillights. In the multiple-vehicle collision, the first crash induces more collisions. We investigate how the first collision induces the chain-reaction crash numerically. We derive, analytically, the transition points and the region maps for the chain-reaction crash in the traffic flow of vehicles with finite sizes. We clarify the effect of the vehicular size on the multiple-vehicle collision.
Chung, Younshik; Chang, IlJoon
2015-11-01
Recently, the introduction of vehicle black box systems or in-vehicle video event data recorders enables the driver to use the system to collect more accurate crash information such as location, time, and situation at the pre-crash and crash moment, which can be analyzed to find the crash causal factors more accurately. This study presents the vehicle black box system in brief and its application status in Korea. Based on the crash data obtained from the vehicle black box system, this study analyzes the accuracy of the crash data collected from existing road crash data recording method, which has been recorded by police officers based on accident parties' statements or eyewitness's account. The analysis results show that the crash data observed by the existing method have an average of 84.48m of spatial difference and standard deviation of 157.75m as well as average 29.05min of temporal error and standard deviation of 19.24min. Additionally, the average and standard deviation of crash speed errors were found to be 9.03km/h and 7.21km/h, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.
Bicycle Guidelines and Crash Rates on Cycle Tracks in the United States
Morency, Patrick; Miranda-Moreno, Luis F.; Willett, Walter C.; Dennerlein, Jack T.
2013-01-01
Objectives. We studied state-adopted bicycle guidelines to determine whether cycle tracks (physically separated, bicycle-exclusive paths adjacent to sidewalks) were recommended, whether they were built, and their crash rate. Methods. We analyzed and compared US bicycle facility guidelines published between 1972 and 1999. We identified 19 cycle tracks in the United States and collected extensive data on cycle track design, usage, and crash history from local communities. We used bicycle counts and crash data to estimate crash rates. Results. A bicycle facility guideline written in 1972 endorsed cycle tracks but American Association of State Highway and Transportation Officials (AASHTO) guidelines (1974–1999) discouraged or did not include cycle tracks and did not cite research about crash rates on cycle tracks. For the 19 US cycle tracks we examined, the overall crash rate was 2.3 (95% confidence interval = 1.7, 3.0) per 1 million bicycle kilometers. Conclusions. AASHTO bicycle guidelines are not explicitly based on rigorous or up-to-date research. Our results show that the risk of bicycle–vehicle crashes is lower on US cycle tracks than published crashes rates on roadways. This study and previous investigations support building cycle tracks. PMID:23678920
Occupational aviation fatalities--Alaska, 2000-2010.
2011-07-01
Aircraft crashes are the second leading cause of occupational deaths in Alaska; during the 1990s, a total of 108 fatal aviation crashes resulted in 155 occupational fatalities. To update data and identify risk factors for occupational death from aircraft crashes, CDC reviewed data from the National Transportation Safety Board (NTSB) and the Alaska Occupational Injury Surveillance System. During 2000--2010, a total of 90 occupational fatalities occurred as a result of 54 crashes, an average of five fatal aircraft crashes and eight fatalities per year. Among those crashes, 21 (39%) were associated with intended takeoffs or landings at landing sites not registered with the Federal Aviation Administration (FAA). Fifteen crashes (28%) were associated with weather, including poor visibility, wind, and turbulence. In addition, 11 crashes (20%) resulted from pilots' loss of aircraft control; nine (17%) from pilots' failure to maintain clearance from terrain, water, or objects; and seven (13%) from engine, structure, or component failure. To reduce occupational fatalities resulting from aircraft crashes in the state, safety interventions should focus on providing weather and other flight information to increase pilots' situational awareness, maintaining pilot proficiency and decision-making abilities, and expanding the infrastructure used by pilots to fly by instruments.
Assessment of aircraft crash frequency for the Hanford site 200 Area tank farms
DOE Office of Scientific and Technical Information (OSTI.GOV)
OBERG, B.D.
2003-03-22
Two factors, the near-airport crash frequency and the non-airport crash frequency, enter into the estimate of the annual aircraft crash frequency at a facility. The near-airport activities, Le., takeoffs and landings from any of the airports in a 23-statute-mile (smi) (20-nautical-mile, [nmi]) radius of the facilities, do not significantly contribute to the annual aircraft crash frequency for the 200 Area tank farms. However, using the methods of DOE-STD-3014-96, the total frequency of an aircraft crash for the 200 Area tank farms, all from non-airport operations, is calculated to be 7.10E-6/yr. Thus, DOE-STD-3014-96 requires a consequence analysis for aircraft crash. Thismore » total frequency consists of contributions from general aviation, helicopter activities, commercial air carriers and air taxis, and from large and small military aircraft. The major contribution to this total is from general aviation with a frequency of 6.77E-6/yr. All other types of aircraft have less than 1E-6/yr crash frequencies. The two individual aboveground facilities were in the realm of 1E-7/yr crash frequencies: 204-AR Waste Unloading Facility at 1.56E-7, and 242-T Evaporator at 8.62E-8. DOE-STD-3009-94, ''Preparation Guide for U.S. Department of Energy Nonreactor Nuclear Facility Documented Safety Analyses'', states that external events, such as aircraft crashes, are referred to as design basis accidents (DBA) and analyzed as such: ''if frequency of occurrence is estimated to exceed 10{sup -6}/yr conservatively calculated'' DOE-STD-3014-96 considers its method for estimating aircraft crash frequency as being conservative. Therefore, DOE-STD-3009-94 requires DBA analysis of an aircraft crash into the 200 Area tank farms. DOE-STD-3009-94 also states that beyond-DBAs are not evaluated for external events. Thus, it requires only a DBA analysis of the effects of an aircraft crash into the 200 Area tank farms. There are two attributes of an aircraft crash into a Hanford waste storage tank, which produce radiological and toxicological effects: the physical-crash, tank-dome-collapse activity, and the ensuing fire from the broken-up fuel.« less
Comparison of identification and ranking methodologies for speed-related crash locations.
DOT National Transportation Integrated Search
2006-06-01
Over 60,000 crashes were reported on the Oregon state highway system from 20002002. Of these, speed was a primary : causal factor in 27% of total crashes and 36% of all fatal crashes. Excessive speed is a driver behavior that can be : influenced b...
Highway safety : research continues on a variety of factors that contribute to motor vehicle crashes
DOT National Transportation Integrated Search
2003-03-31
Nearly 6.3 million motor vehicle crashes occurred in the United States in 2001, or one crash every 5 seconds. This study examined human, environmental, and vehicle factors that contribute to crashes. As requested, this report provides more recent inf...
DOT National Transportation Integrated Search
1997-01-01
Countermeasures for motor vehicle crashes are often determined after extensive data analysis of the crash history of a roadway segment. An important factor that drives the value of this analysis is the accuracy, or precision, with which the crash is ...
Analysis of light vehicle crashes and pre-crash scenarios based on the 2000 General Estimates System
DOT National Transportation Integrated Search
2003-02-01
This report analyzes the problem of light vehicle crashes in the United States to support the development and assessment of effective crash avoidance systems as part of the U.S. Department of Transportation's Intelligent Vehicle Initiative. The analy...
DOT National Transportation Integrated Search
2013-04-30
This report discusses light-vehicle crash countermeasure profiles and functions for five target pre-crash scenario groups based on vehicle-to-vehicle (V2V) communications. Target pre-crash scenario groups include rear-end, lane change, opposite direc...
Buckis, Samantha; Lenné, Mike G; Fitzharris, Michael
2015-01-01
The elevated crash involvement rate of young drivers is well documented. Given the higher crash risk of young drivers and the need for innovative policy and programs, it remains important to fully understand the type of crashes young drivers are involved in, and knowledge of the lifetime care cost of crashes can support effective policy development. The aim of this article is to document the number and type of young driver crashes, as well as the associated lifetime care cost over a 9-year period (2005-2013) in Victoria, Australia. In Victoria, Australia, the Transport Accident Commission (TAC) has legislated responsibility for road safety and the care of persons injured in road crashes, irrespective of fault. TAC claims data for the period 2005-2013 were used to document the number and type of young driver crashes. Lifetime care costs (past and future payment liabilities) were calculated by Taylor Fry actuarial consultancy. License and population data were used to define the crash involvement rate of young drivers. Over the 9-year period, 16,817 claims were lodged to the TAC by drivers 18-25 years of age following a crash. There were 646 fewer drivers aged 18-25 killed and injured in 2013, compared to 2005, representing an unadjusted change of -28.7% (-29.8% males; -28.4% females). The total lifetime care cost of young drivers killed and injured in Victoria for the period 2005-2013 was estimated to be AU$634 million (US$493 million). Differences between males and females, single- and multivehicle crashes, and fatalities and injuries were found to be statistically significant. Run-off-road crashes and crashes from opposing direction were overrepresented in the lifetime care costs for young driver claimants. Twenty-eight injured drivers were classified as high-severity claims. These 28 claimants require additional long-term care, which was estimated to be AU$219 million; of these 28, 24 were male (85.7%). The long-term care costs for these 28 drivers (0.16%) accounts for 34.5% of the total lifetime care cost of all 18- to 25-year-old injured drivers. By using no-fault lifetime care costs that account for medical and like expenses, rehabilitation, and social reintegration costs, a more accurate understanding of the cost of young driver crashes can be determined. Application of these costs to specific crash types highlights new priorities and opportunities for developing programs to reduce young driver crashes.
Real-world injury patterns associated with Hybrid III sternal deflections in frontal crash tests.
Brumbelow, Matthew L; Farmer, Charles M
2013-01-01
This study investigated the relationship between the peak sternal deflection measurements recorded by the Hybrid III 50th percentile male anthropometric test device (ATD) in frontal crash tests and injury and fatality outcomes for drivers in field crashes. ATD sternal deflection data were obtained from the Insurance Institute for Highway Safety's 64 km/h, 40 percent overlap crashworthiness evaluation tests for vehicles with seat belt crash tensioners, load limiters, and good-rated structure. The National Automotive Sampling System Crashworthiness Data System (NASS-CDS) was queried for frontal crashes of these vehicles in which the driver was restrained by a seat belt and air bag. Injury probability curves were calculated by frontal crash type using the injuries coded in NASS-CDS and peak ATD sternal deflection data. Fatality Analysis Reporting System (FARS) front-to-front crashes with exactly one driver death were also studied to determine whether the difference in measured sternal deflections for the 2 vehicles was related to the odds of fatality. For center impacts, moderate overlaps, and large overlaps in NASS-CDS, the probability of the driver sustaining an Abbreviated Injury Scale (AIS) score ≥ 3 thoracic injury, or any nonextremity AIS ≥ 3 injury, increased with increasing ATD sternal deflection measured in crash tests. For small overlaps, however, these probabilities decreased with increasing deflection. For FARS crashes, the fatally injured driver more often was in the vehicle with the lower measured deflection in crash tests (55 vs. 45%). After controlling for other factors, a 5-mm difference in measured sternal deflections between the 2 vehicles was associated with a fatality odds ratio of 0.762 for the driver in the vehicle with the greater deflection (95% confidence interval = 0.373, 1.449). Restraint systems that reduce peak Hybrid III sternal deflection in a moderate overlap crash test are beneficial in real-world crashes with similar or greater overlap but likely have a disbenefit in crashes with small overlap. This may occur because belt-force limiters employed to control deflections allow excursion that could produce contact with interior vehicle components in small overlaps, given the more oblique occupant motion and potential inboard movement of the air bag. Although based on a limited number of cases, this interpretation is supported by differences in skeletal fracture locations among drivers in crashes with different overlaps. Current restraint systems could be improved by designs that reduce sternal deflection in moderate and large overlap crashes without increasing occupant excursion in small overlap crashes.
Air Cushion Crash Rescue Vehicle (ACCRV) (Phase 1)
1985-11-01
903-T 600 2450 *Detroit Diesel 8V-92TA 736 2250 Detroit Diesel 8V-71TA 600 2090 Detroit Disel 6V-53T* 350 1360 Garrett GT601 540 2170 John Deere...Dependent 6096 (Traction Limit) 596 4096 @ 1 mph DD8V9296A 2 cycle, 8 cycle diesel, turbo charged 4.84 inches 5.0 in. 736 cu in. 17:1 DF1
Grief and Group Recovery Following a Military Air Disaster
1990-01-01
stages of human development , the unlabelled cells are meant to suggest individuals who either accelerate through phases more quick- ly than the norm...and far-reaching ( Erikson , 1976; Titchener and Kapp, 1976). Such was apparently the case following the December 1988 crash of Pan Am flight 103 in...the normal processes of group recovery and reintegration after sudden, traumatic loss. The present study takes a necessary step in developing this
Sagberg, Fridulv
2018-08-01
Drivers or riders without a valid license are involved in 10% of fatal road crashes in Norway. This was shown by an analysis of data from all fatal crashes in the period 2005-2014. A literature review shows that unlicensed drivers have a considerably increased crash risk. Such crashes could be prevented by electronic driver authentication, i.e., a technical system for checking that a driver or rider has legal access to a vehicle before driving is permitted. This can be done by requiring the driver/rider to identify themselves with a national identity number and a unique code or biometric information before driving may commence. The vehicle thereafter verifies license availability and vehicle access by communication with a central register. In more than 80% of fatal crashes with unlicensed drivers/riders, speeding and/or drug influence contributed to the crash. This means that a majority of crashes with unlicensed drivers alternatively could be prevented by already available systems, such as alcolock and speed limit dependent speed adapters. These systems will have a wider influence, by preventing crashes also among licensed drivers. Mandatory implementation of alcolock, speed limiter, and electronic driver authentication in all motorized vehicles is estimated to prevent up to 28% of fatal road crashes, depending on effectiveness of the systems. Copyright © 2018 Elsevier Ltd. All rights reserved.
Driver crash risk factors and prevalence evaluation using naturalistic driving data.
Dingus, Thomas A; Guo, Feng; Lee, Suzie; Antin, Jonathan F; Perez, Miguel; Buchanan-King, Mindy; Hankey, Jonathan
2016-03-08
The accurate evaluation of crash causal factors can provide fundamental information for effective transportation policy, vehicle design, and driver education. Naturalistic driving (ND) data collected with multiple onboard video cameras and sensors provide a unique opportunity to evaluate risk factors during the seconds leading up to a crash. This paper uses a National Academy of Sciences-sponsored ND dataset comprising 905 injurious and property damage crash events, the magnitude of which allows the first direct analysis (to our knowledge) of causal factors using crashes only. The results show that crash causation has shifted dramatically in recent years, with driver-related factors (i.e., error, impairment, fatigue, and distraction) present in almost 90% of crashes. The results also definitively show that distraction is detrimental to driver safety, with handheld electronic devices having high use rates and risk.
Driver crash risk factors and prevalence evaluation using naturalistic driving data
Dingus, Thomas A.; Guo, Feng; Lee, Suzie; Antin, Jonathan F.; Perez, Miguel; Buchanan-King, Mindy; Hankey, Jonathan
2016-01-01
The accurate evaluation of crash causal factors can provide fundamental information for effective transportation policy, vehicle design, and driver education. Naturalistic driving (ND) data collected with multiple onboard video cameras and sensors provide a unique opportunity to evaluate risk factors during the seconds leading up to a crash. This paper uses a National Academy of Sciences-sponsored ND dataset comprising 905 injurious and property damage crash events, the magnitude of which allows the first direct analysis (to our knowledge) of causal factors using crashes only. The results show that crash causation has shifted dramatically in recent years, with driver-related factors (i.e., error, impairment, fatigue, and distraction) present in almost 90% of crashes. The results also definitively show that distraction is detrimental to driver safety, with handheld electronic devices having high use rates and risk. PMID:26903657
Bernat, Debra H; Maldonado-Molina, Mildred; Hyland, Andrew; Wagenaar, Alexander C
2013-02-01
We examined effects of New York and California's statewide smoke-free restaurant and bar policies on alcohol-related car crash fatalities. We used an interrupted time-series design from 1982 to 2008, with 312 monthly observations, to examine the effect of each state's law on single-vehicle-nighttime crashes and crashes involving a driver with a blood alcohol concentration of 0.08 grams per deciliter or greater. Implementation of New York and California's statewide smoke-free policies was not associated with alcohol-related car crash fatalities. Additionally, analyses showed no effect of New York's smoke-free policy on alcohol-related car crash fatalities in communities along the Pennsylvania-New York border. Statewide smoke-free restaurant and bar laws do not appear to affect rates of alcohol-related car crashes.
The effects of electronic stability control (ESC) on crashes--an update.
Høye, Alena
2011-05-01
The present study is an update of the meta-analysis by Erke (Erke, A., 2008. Effects of Electronic Stability Control (ESC) on accidents: a review of empirical evidence. Accident Analysis & Prevention, 40 (1), 167-173). Results from 12 studies of the effects of Electronic Stability Control (ESC) on the number of different types of crashes were summarized by means of meta-analysis. The results indicate that ESC prevents about 40% of all crashes involving loss of control. The greatest reductions were found for rollover crashes (-50%), followed by run-off-road (-40%) and single vehicle crashes (-25%). These results are however likely to be somewhat overestimated, especially for non-fatal crashes. Multiple vehicle crashes were found to be largely unchanged. Reductions were found for some types of multiple vehicle crashes. Rear-end collisions are unchanged or may increase. Fatal crashes involving pedestrians, bicycles or animals were found to increase as well. ESC was found to be more effective in preventing fatal crashes than non-fatal crashes. ESC is often found to be more effective in Sports Utility Vehicles (SUVs) than in passenger cars. This may be due to differences between drivers of SUVs and passenger cars. The results from meta-analysis indicate that drivers of ESC-equipped vehicles are likely to be safer drivers than other drivers. All the same, ESC may lead to behavioural adaptation in some cases, but it is not likely that behavioural adaptation offsets the positive safety effects. This may be due to a lack of knowledge about ESC. Copyright © 2010 Elsevier Ltd. All rights reserved.
Theofilatos, Athanasios; Yannis, George; Kopelias, Pantelis; Papadimitriou, Fanis
2018-01-04
Considerable efforts have been made from researchers and policy makers in order to explain road crash occurrence and improve road safety performance of highways. However, there are cases when crashes are so few that they could be considered as rare events. In such cases, the binary dependent variable is characterized by dozens to thousands of times fewer events (crashes) than non-events (non-crashes). This paper attempts to add to the current knowledge by investigating crash likelihood by utilizing real-time traffic data and by proposing a framework driven by appropriate statistical models (Bias Correction and Firth method) in order to overcome the problems that arise when the number of crashes is very low. Under this approach instead of using traditional logistic regression methods, crashes are considered as rare events In order to demonstrate this approach, traffic data were collected from three random loop detectors in the Attica Tollway ("Attiki Odos") located in Greater Athens Area in Greece for the 2008-2011 period. The traffic dataset consists of hourly aggregated traffic data such as flow, occupancy, mean time speed and percentage of trucks in traffic. This study demonstrates the application and findings of our approach and revealed a negative relationship between crash occurrence and speed in crash locations. The method and findings of the study attempt to provide insights on the mechanism of crash occurrence and also to overcome data considerations for the first time in safety evaluation of motorways. Copyright © 2017 Elsevier Ltd. All rights reserved.
Effects of legislative reform to reduce drunken driving and alcohol-related traffic fatalities.
Hingson, R W; Howland, J; Levenson, S
1988-01-01
From 1980 through 1985, considerable progress was made across the Nation in reducing drunken driving and fatal automobile crashes. More than 400 chapters of local citizen groups concerned with reducing drunken driving were formed. New media coverage, measured in number of stories, increased fiftyfold from 1980 to 1984. More than 500 legislative reforms were passed. All States now have adopted a legal drinking age of 21. Many also adopted criminal and administrative per se laws and instituted penalty increases for drunken driving. By 1985, the total number of fatal crashes declined to 39,168, a decrease of 6,116, or 16 percent, from the 1980 level of 45,284. Single-vehicle fatal crashes occurring at night, those most likely to involve alcohol, declined by 20 percent, with 3,674 fewer crashes in 1985 than in 1980. Among teenage drivers, declines in fatal crashes were steeper: Fatal crashes decreased 26 percent, and single-vehicle night fatal crashes were down 34 percent. After 1984, however, the number of new citizen groups established and the number of stories appearing in the media began to decline. In 1986, after decreasing for several years, the number of fatal crashes rose 5 percent, and single-vehicle night fatal crashes rose 7 percent, up 1,060 from 1985. Among teenage drivers, the increase in single-vehicle night fatal crashes was even higher, up 17 percent. In 1987, single-vehicle night fatal crashes declined slightly but still remained higher than in 1983, 1984, or 1985.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3141962
Injury risk functions for frontal oblique collisions.
Andricevic, Nino; Junge, Mirko; Krampe, Jonas
2018-03-09
The objective of this article was the construction of injury risk functions (IRFs) for front row occupants in oblique frontal crashes and a comparison to IRF of nonoblique frontal crashes from the same data set. Crashes of modern vehicles from GIDAS (German In-Depth Accident Study) were used as the basis for the construction of a logistic injury risk model. Static deformation, measured via displaced voxels on the postcrash vehicles, was used to calculate the energy dissipated in the crash. This measure of accident severity was termed objective equivalent speed (oEES) because it does not depend on the accident reconstruction and thus eliminates reconstruction biases like impact direction and vehicle model year. Imputation from property damage cases was used to describe underrepresented low-severity crashes-a known shortcoming of GIDAS. Binary logistic regression was used to relate the stimuli (oEES) to the binary outcome variable (injured or not injured). IRFs for the oblique frontal impact and nonoblique frontal impact were computed for the Maximum Abbreviated Injury Scale (MAIS) 2+ and 3+ levels for adults (18-64 years). For a given stimulus, the probability of injury for a belted driver was higher in oblique crashes than in nonoblique frontal crashes. For the 25% injury risk at MAIS 2+ level, the corresponding stimulus for oblique crashes was 40 km/h but it was 64 km/h for nonoblique frontal crashes. The risk of obtaining MAIS 2+ injuries is significantly higher in oblique crashes than in nonoblique crashes. In the real world, most MAIS 2+ injuries occur in an oEES range from 30 to 60 km/h.
Mahajan, Narinder; Aggarwal, Meenu; Raina, Sunil; Verma, Lekh Raj; Mazta, Salig Ram; Gupta, B P
2013-07-01
What are the various injuries in road traffic crash cases? To study various non-fatal injuries in road traffic crash cases. Hospital based Descriptive study. The study population comprised of 401 consecutive cases of non- fatal injuries involved in road traffic crashes and reported at Indira Gandhi Medical College hospital, Shimla. 1(st) June 2005 to 31(st) May 2006. Demographic characteristics of the victims, pattern of injuries and hospital stay of the victims. Types of crashes, time, day and month of crashes, vehicles involved in crashes, use of protective gear etc. Percentages, Proportions. 73% of the injured victims were young between 20-49yrs, male to female ratio being 5.3:1. Employees (34.7%) and occupants of transport vehicles (45.9%) constituted the maximum number of the victims. Major injuries (fractures and abd. injuries) were reported in 53.4% of the victims and fractures of lower limb were the commonest of the injuries (26.3%). Use of seat-belt was found to be alarmingly low (14.3%) amongst the four- wheeler users and its non-use was found to be significantly associated with the major injuries. Helmet was used by 36 cases (66.7%) out of total of 54 users of motorized two-wheelers at the time of crash. Human error was the most reported cause of crash (82%) and the most common mode of crash was skidding and/rolling down (55%).23.1% of the drivers were reported to have consumed alcohol at the time of crash.
Multilevel analysis of the role of human factors in regional disparities in crash outcomes.
Adanu, Emmanuel Kofi; Smith, Randy; Powell, Lars; Jones, Steven
2017-12-01
A growing body of research has examined the disparities in road traffic safety among population groups and geographic regions. These studies reveal disparities in crash outcomes between people and regions with different socioeconomic characteristics. A critical aspect of the road traffic crash epidemic that has received limited attention is the influence of local characteristics on human elements that increase the risk of getting into a crash. This paper applies multilevel logistic regression modeling techniques to investigate the influence of driver residential factors on driver behaviors in an attempt to explain the area-based differences in the severity of road crashes across the State of Alabama. Specifically, the paper reports the effects of characteristics attributable to drivers and the geographic regions they reside on the likelihood of a crash resulting in serious injuries. Model estimation revealed that driver residence (postal code or region) accounted for about 7.3% of the variability in the probability of a driver getting into a serious injury crash, regardless of driver characteristics. The results also reveal disparities in serious injury crash rate as well as significant proportions of serious injury crashes involving no seatbelt usage, driving under influence (DUI), unemployed drivers, young drivers, distracted driving, and African American drivers among some regions. The average credit scores, average commute times, and populations of driver postal codes are shown to be significant predictors for risk of severe injury crashes. This approach to traffic crash analysis presented can serve as the foundation for evidence-based policies and also guide the implementation of targeted countermeasures. Copyright © 2017 Elsevier Ltd. All rights reserved.
Case-control analysis in highway safety: Accounting for sites with multiple crashes.
Gross, Frank
2013-12-01
There is an increased interest in the use of epidemiological methods in highway safety analysis. The case-control and cohort methods are commonly used in the epidemiological field to identify risk factors and quantify the risk or odds of disease given certain characteristics and factors related to an individual. This same concept can be applied to highway safety where the entity of interest is a roadway segment or intersection (rather than a person) and the risk factors of interest are the operational and geometric characteristics of a given roadway. One criticism of the use of these methods in highway safety is that they have not accounted for the difference between sites with single and multiple crashes. In the medical field, a disease either occurs or it does not; multiple occurrences are generally not an issue. In the highway safety field, it is necessary to evaluate the safety of a given site while accounting for multiple crashes. Otherwise, the analysis may underestimate the safety effects of a given factor. This paper explores the use of the case-control method in highway safety and two variations to account for sites with multiple crashes. Specifically, the paper presents two alternative methods for defining cases in a case-control study and compares the results in a case study. The first alternative defines a separate case for each crash in a given study period, thereby increasing the weight of the associated roadway characteristics in the analysis. The second alternative defines entire crash categories as cases (sites with one crash, sites with two crashes, etc.) and analyzes each group separately in comparison to sites with no crashes. The results are also compared to a "typical" case-control application, where the cases are simply defined as any entity that experiences at least one crash and controls are those entities without a crash in a given period. In a "typical" case-control design, the attributes associated with single-crash segments are weighted the same as the attributes of segments with multiple crashes. The results support the hypothesis that the "typical" case-control design may underestimate the safety effects of a given factor compared to methods that account for sites with multiple crashes. Compared to the first alternative case definition (where multiple crash segments represent multiple cases) the results from the "typical" case-control design are less pronounced (i.e., closer to unity). The second alternative (where case definitions are constructed for various crash categories and analyzed separately) provides further evidence that sites with single and multiple crashes should not be grouped together in a case-control analysis. This paper indicates a clear need to differentiate sites with single and multiple crashes in a case-control analysis. While the results suggest that sites with multiple crashes can be accounted for using a case-control design, further research is needed to determine the optimal method for addressing this issue. This paper provides a starting point for that research. Copyright © 2012 Elsevier Ltd. All rights reserved.
DOT National Transportation Integrated Search
2009-01-01
In 2004, a total of 95,020 vehicle crashes occurred on highways under the jurisdiction of the Virginia Department of Transportation (VDOT). Of these, 39,847 crashes occurred on primary highways, and 345 of these were fatal crashes. VDOT's traffic eng...
Effect of speed limit increase on crash rate on rural two-lane highways in Louisiana.
DOT National Transportation Integrated Search
2006-08-01
This study investigated the impact of a speed limit increase on the crash rate on rural twolane roads in Louisiana. The Louisiana crash database for 1999-2004 was used to compare rates of different crash severities and types before and after a speed ...
Developing inexpensive crash countermeasures for Louisiana local roads : project research capsule.
DOT National Transportation Integrated Search
2011-02-01
Local roads make up 73 percent of all road miles in Louisiana and have : 40 perfect of all crashes that occur yearly on Louisiana roads. Over the : past 5 years, 851 fatal crashes, over 81,000 injury crashes, and over 23,000 : property-damage-only cr...
DOT National Transportation Integrated Search
2013-04-30
A template of pre-crash scenarios is presented to depict national crash statistics and kinematic information of time-to-collision for the design of appropriate crash countermeasures based on vehicle-to-vehicle (V2V) communications. This template serv...
DOT National Transportation Integrated Search
2016-10-01
The development of safety performance functions (SPFs) and crash modification factors (CMFs) requires data on traffic exposure. The analysis of motorcycle crashes can be especially challenging in this regard because few jurisdictions collect motorcyc...
DOT National Transportation Integrated Search
2012-08-01
Roadway departure crashes correspond to approximately 40% of all traffic crashes. According to the most recent national crash statistics, in 2009, there were 11,185 fatal roadway departure crashes on rural highways, resulting in 23,169 fatalities. Th...
An assessment of the crash fire hazard of liquid hydrogen fueled aircraft
NASA Technical Reports Server (NTRS)
1982-01-01
The crash fire hazards of liquid hydrogen fueled aircraft relative to those of mission equivalent aircraft fueled either with conventional fuel or with liquefied methane were evaluated. The aircraft evaluated were based on Lockheed Corporation design for 400 passenger, Mach 0.85, 5500 n. mile aircraft. Four crash scenarios were considered ranging from a minor incident causing some loss of fuel system integrity to a catastrophic crash. Major tasks included a review of hazardous properties of the alternate fuels and of historic crash fire data; a comparative hazard evluation for each of the three fuels under four crash scenarios a comprehensive review and analysis and an identification of areas further development work. The conclusion was that the crash fire hazards are not significantly different when compared in general for the three fuels, although some fuels showed minor advantages in one respect or another.
Maldonado-Molina, Mildred; Hyland, Andrew; Wagenaar, Alexander C.
2013-01-01
We examined effects of New York and California’s statewide smoke-free restaurant and bar polices on alcohol-related car crash fatalities. We used an interrupted time-series design from 1982 to 2008, with 312 monthly observations, to examine the effect of each state’s law on single-vehicle-nighttime crashes and crashes involving a driver with a blood alcohol concentration of 0.08 grams per deciliter or greater. Implementation of New York and California’s statewide smoke-free policies was not associated with alcohol-related car crash fatalities. Additionally, analyses showed no effect of New York’s smoke-free policy on alcohol-related car crash fatalities in communities along the Pennsylvania-New York border. Statewide smoke-free restaurant and bar laws do not appear to affect rates of alcohol-related car crashes. PMID:23237160
Rizzi, Matteo; Strandroth, Johan; Tingvall, Claes
2009-10-01
This study set out to evaluate the effectiveness of antilock brake system (ABS) technology on motorcycles in reducing real-life injury crashes and to mitigate injury severity. The study comprised an analysis of in-depth fatal crash data in Sweden during 2005-2008 to investigate the potential of ABS as well an estimate of the effectiveness of ABS in crash reduction in Sweden between 2003 and 2008 using induced exposure methods. Findings show that head-on collisions were the least ABS-affected crash types and collisions at intersections the most influenced. Induced exposure analysis showed that the overall effectiveness of ABS was 38 percent on all crashes with injuries and 48 percent on all severe and fatal crashes, with a minimum effectiveness of 11 and 17 percent, respectively. The study recommends the fitment of ABS on all new motorcycles as soon as possible and that customers only purchase motorcycles with ABS.
Fatal crashes of passenger vehicles before and after adding antilock braking systems.
Farmer, C M; Lund, A K; Trempel, R E; Braver, E R
1997-11-01
Fatal crash rates of passenger cars and vans were compared for the last model year before four-wheel antilock brakes were introduced and the first model year for which antilock brakes were standard equipment. Vehicles selected for analysis had no other significant design changes between the model years being compared, and the model years with and without antilocks were no more than two years apart. The overall fatal crash rates were similar for the two model years. However, the vehicles with antilocks were significantly more likely to be involved in crashes fatal to their own occupants, particularly single-vehicle crashes. Conversely, antilock vehicles were less likely to be involved in crashes fatal to occupants of other vehicles or nonoccupants (pedestrians, bicyclists). Overall, antilock brakes appear to have had little effect on fatal crash involvement. Further study is needed to better understand why fatality risk has increased for occupants of antilock vehicles.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-29
...: Title: Motorcycle Crash Causation Study and Pilot Motorcycle Crash Causes and Outcomes Study. OMB... (OTC) for the purpose of conducting a comprehensive, in-depth motorcycle crash causation study that... that may have been relevant to the crash. The second procedure, known as the case-control procedure...
Ivers, Rebecca; Senserrick, Teresa; Boufous, Soufiane; Stevenson, Mark; Chen, Huei-Yang; Woodward, Mark; Norton, Robyn
2009-09-01
We explored the risky driving behaviors and risk perceptions of a cohort of young novice drivers and sought to determine their associations with crash risk. Provisional drivers aged 17 to 24 (n = 20 822) completed a detailed questionnaire that included measures of risk perception and behaviors; 2 years following recruitment, survey data were linked to licensing and police-reported crash data. Poisson regression models that adjusted for multiple confounders were created to explore crash risk. High scores on questionnaire items for risky driving were associated with a 50% increased crash risk (adjusted relative risk = 1.51; 95% confidence interval = 1.25, 1.81). High scores for risk perception (poorer perceptions of safety) were also associated with increased crash risk in univariate and multivariate models; however, significance was not sustained after adjustment for risky driving. The overrepresentation of youths in crashes involving casualties is a significant public health issue. Risky driving behavior is strongly linked to crash risk among young drivers and overrides the importance of risk perceptions. Systemwide intervention, including licensing reform, is warranted.
Torres, Pedro; Romano, Eduardo; Voas, Robert B.; de la Rosa, Mario; Lacey, John H.
2014-01-01
Introduction The literature presents a puzzling picture of Latinos being overrepresented in alcohol-related crashes, but not in noncrash drinking and driving. This report examines if, like other demographic variables in which some groups are at a higher crash risk than others (e.g., young drivers), different racial/ethnic groups face different crash risks Method This study compares blood-alcohol information from the 2006–2007 U.S. Fatality Analysis Reporting System (FARS) with control data from the 2007 U.S. National Roadside Survey. Logistic regression, including a dual interaction between BAC and race/ethnicity, was used to estimate crash risk at different BAC levels. Results It was found that, although Hispanic and African-American drivers were less likely to be involved in single-vehicle crashes than their White counterparts, all drivers face similar BAC relative crash risk regardless of their group membership. The overrepresentation of Latino drivers in alcohol-related crashes could be explained by differences in patterns of consumption, driving exposure, lack of awareness of driving rules, and/or socioeconomics. PMID:24529097
Contributory factors to traffic crashes at signalized intersections in Hong Kong.
Wong, S C; Sze, N N; Li, Y C
2007-11-01
Efficient geometric design and signal timing not only improve operational performance at signalized intersections by expanding capacity and reducing traffic delays, but also result in an appreciable reduction in traffic conflicts, and thus better road safety. Information on the incidence of crashes, traffic flow, geometric design, road environment, and traffic control at 262 signalized intersections in Hong Kong during 2002 and 2003 are incorporated into a crash prediction model. Poisson regression and negative binomial regression are used to quantify the influence of possible contributory factors on the incidence of killed and severe injury (KSI) crashes and slight injury crashes, respectively, while possible interventions by traffic flow are controlled. The results for the incidence of slight injury crashes reveal that the road environment, degree of curvature, and presence of tram stops are significant factors, and that traffic volume has a diminishing effect on the crash risk. The presence of tram stops, number of pedestrian streams, road environment, proportion of commercial vehicles, average lane width, and degree of curvature increase the risk of KSI crashes, but the effect of traffic volume is negligible.
To brake or to accelerate? Safety effects of combined speed and red light cameras.
De Pauw, Ellen; Daniels, Stijn; Brijs, Tom; Hermans, Elke; Wets, Geert
2014-09-01
The present study evaluates the traffic safety effect of combined speed and red light cameras at 253 signalized intersections in Flanders, Belgium that were installed between 2002 and 2007. The adopted approach is a before-and-after study with control for the trend. The analyses showed a non-significant increase of 5% in the number of injury crashes. An almost significant decrease of 14% was found for the more severe crashes. The number of rear-end crashes turned out to have increased significantly (+44%), whereas a non-significant decrease (-6%) was found in the number of side crashes. The decrease for the severe crashes was mainly attributable to the effect on side crashes, for which a significant decrease of 24% was found. It is concluded that combined speed and red light cameras have a favorable effect on traffic safety, in particular on severe crashes. However, future research should examine the circumstances of rear-end crashes and how this increase can be managed. Copyright © 2014 National Safety Council and Elsevier Ltd. All rights reserved.
A kinetic energy model of two-vehicle crash injury severity.
Sobhani, Amir; Young, William; Logan, David; Bahrololoom, Sareh
2011-05-01
An important part of any model of vehicle crashes is the development of a procedure to estimate crash injury severity. After reviewing existing models of crash severity, this paper outlines the development of a modelling approach aimed at measuring the injury severity of people in two-vehicle road crashes. This model can be incorporated into a discrete event traffic simulation model, using simulation model outputs as its input. The model can then serve as an integral part of a simulation model estimating the crash potential of components of the traffic system. The model is developed using Newtonian Mechanics and Generalised Linear Regression. The factors contributing to the speed change (ΔV(s)) of a subject vehicle are identified using the law of conservation of momentum. A Log-Gamma regression model is fitted to measure speed change (ΔV(s)) of the subject vehicle based on the identified crash characteristics. The kinetic energy applied to the subject vehicle is calculated by the model, which in turn uses a Log-Gamma Regression Model to estimate the Injury Severity Score of the crash from the calculated kinetic energy, crash impact type, presence of airbag and/or seat belt and occupant age. Copyright © 2010 Elsevier Ltd. All rights reserved.
Helicopter crashes into water: warning time, final position, and other factors affecting survival.
Brooks, Christopher J; MacDonald, Conor V; Baker, Susan P; Shanahan, Dennis F; Haaland, Wren L
2014-04-01
According to 40 yr of data, the fatality rate for a helicopter crash into water is approximately 25%. Does warning time and the final position of the helicopter in the water influence the survival rate? The National Transportation Safety Board (NTSB) database was queried to identify helicopter crashes into water between 1981 and 2011 in the Gulf of Mexico and Hawaii. Fatality rate, amount of warning time prior to the crash, and final position of the helicopter were identified. There were 133 helicopters that crashed into water with 456 crew and passengers. Of these, 119 occupants (26%) did not survive; of those who did survive, 38% were injured. Twelve died after making a successful escape from the helicopter. Crashes with < 15 s warning had a fatality rate of 22%, compared to 12% for 16-60 s warning and 5% for > 1 min. However, more than half of fatalities (57%) came from crashes for which the warning time could not be determined. Lack of warning time and how to survive in the water after the crash should be a topic for study in all marine survival/aircraft ditching courses. Investigators should be trained to provide estimates of warning time when investigating helicopter crashes into water.
Pre-crash scenarios at road junctions: A clustering method for car crash data.
Nitsche, Philippe; Thomas, Pete; Stuetz, Rainer; Welsh, Ruth
2017-10-01
Given the recent advancements in autonomous driving functions, one of the main challenges is safe and efficient operation in complex traffic situations such as road junctions. There is a need for comprehensive testing, either in virtual simulation environments or on real-world test tracks. This paper presents a novel data analysis method including the preparation, analysis and visualization of car crash data, to identify the critical pre-crash scenarios at T- and four-legged junctions as a basis for testing the safety of automated driving systems. The presented method employs k-medoids to cluster historical junction crash data into distinct partitions and then applies the association rules algorithm to each cluster to specify the driving scenarios in more detail. The dataset used consists of 1056 junction crashes in the UK, which were exported from the in-depth "On-the-Spot" database. The study resulted in thirteen crash clusters for T-junctions, and six crash clusters for crossroads. Association rules revealed common crash characteristics, which were the basis for the scenario descriptions. The results support existing findings on road junction accidents and provide benchmark situations for safety performance tests in order to reduce the possible number parameter combinations. Copyright © 2017 Elsevier Ltd. All rights reserved.
Innovative Anti Crash Absorber for a Crashworthy Landing Gear
NASA Astrophysics Data System (ADS)
Guida, Michele; Marulo, Francesco; Montesarchio, Bruno; Bruno, Massimiliano
2014-06-01
This paper defines an innovative concept to anti-crash absorber in composite material to be integrated on the landing gear as an energy-absorbing device in crash conditions to absorb the impact energy. A composite cylinder tube in carbon fiber material is installed coaxially to the shock absorber cylinder and, in an emergency landing gear condition, collapses in order to enhance the energy absorption performance of the landing system. This mechanism has been developed as an alternative solution to a high-pressure chamber installed on the Agusta A129 CBT helicopter, which can be considered dangerous when the helicopter operates in hard and/or crash landing. The characteristics of the anti-crash device are presented and the structural layout of a crashworthy landing gear adopting the developed additional energy absorbing stage is outlined. Experimental and numerical results relevant to the material characterization and the force peaks evaluation of the system development are reported. The anti-crash prototype was designed, analysed, optimized, made and finally the potential performances of a landing gear with the additional anti-crash absorber system are tested by drop test and then correlated with a similar test without the anti-crash system, showing that appreciable energy absorbing capabilities and efficiencies can be obtained in crash conditions.
Comparison of Test and Finite Element Analysis for Two Full-Scale Helicopter Crash Tests
NASA Technical Reports Server (NTRS)
Annett, Martin S.; Horta,Lucas G.
2011-01-01
Finite element analyses have been performed for two full-scale crash tests of an MD-500 helicopter. The first crash test was conducted to evaluate the performance of a composite deployable energy absorber under combined flight loads. In the second crash test, the energy absorber was removed to establish the baseline loads. The use of an energy absorbing device reduced the impact acceleration levels by a factor of three. Accelerations and kinematic data collected from the crash tests were compared to analytical results. Details of the full-scale crash tests and development of the system-integrated finite element model are briefly described along with direct comparisons of acceleration magnitudes and durations for the first full-scale crash test. Because load levels were significantly different between tests, models developed for the purposes of predicting the overall system response with external energy absorbers were not adequate under more severe conditions seen in the second crash test. Relative error comparisons were inadequate to guide model calibration. A newly developed model calibration approach that includes uncertainty estimation, parameter sensitivity, impact shape orthogonality, and numerical optimization was used for the second full-scale crash test. The calibrated parameter set reduced 2-norm prediction error by 51% but did not improve impact shape orthogonality.
Long-term impact on alcohol-involved crashes of lowering the minimum purchase age in New Zealand.
Huckle, Taisia; Parker, Karl
2014-06-01
We assessed the long-term effect of lowering the minimum purchase age for alcohol from age 20 to age 18 years on alcohol-involved crashes in New Zealand. We modeled ratios of drivers in alcohol-involved crashes to drivers in non-alcohol-involved crashes by age group in 3 time periods using logistic regression, controlling for gender and adjusting for multiple comparisons. Before the law change, drivers aged 18 to 19 and 20 to 24 years had similar odds of an alcohol-involved crash (P = .1). Directly following the law change, drivers aged 18 to 19 years had a 15% higher odds of being in an alcohol-involved crash than did drivers aged 20 to 24 years (P = .038). In the long term, drivers aged 18 to 19 years had 21% higher odds of an alcohol-involved crash than did the age control group (P ≤ .001). We found no effects for fatal alcohol-involved crashes alone and no trickle-down effects for the youngest group. Lowering the purchase age for alcohol was associated with a long-term impact on alcohol-involved crashes among drivers aged 18 to 19 years. Raising the minimum purchase age for alcohol would be appropriate.
Chen, Feng; Chen, Suren; Ma, Xiaoxiang
2016-01-01
Traffic and environmental conditions (e.g., weather conditions), which frequently change with time, have a significant impact on crash occurrence. Traditional crash frequency models with large temporal scales and aggregated variables are not sufficient to capture the time-varying nature of driving environmental factors, causing significant loss of critical information on crash frequency modeling. This paper aims at developing crash frequency models with refined temporal scales for complex driving environments, with such an effort providing more detailed and accurate crash risk information which can allow for more effective and proactive traffic management and law enforcement intervention. Zero-inflated, negative binomial (ZINB) models with site-specific random effects are developed with unbalanced panel data to analyze hourly crash frequency on highway segments. The real-time driving environment information, including traffic, weather and road surface condition data, sourced primarily from the Road Weather Information System, is incorporated into the models along with site-specific road characteristics. The estimation results of unbalanced panel data ZINB models suggest there are a number of factors influencing crash frequency, including time-varying factors (e.g., visibility and hourly traffic volume) and site-varying factors (e.g., speed limit). The study confirms the unique significance of the real-time weather, road surface condition and traffic data to crash frequency modeling. PMID:27322306
Long-Term Impact on Alcohol-Involved Crashes of Lowering the Minimum Purchase Age in New Zealand
Parker, Karl
2014-01-01
Objectives. We assessed the long-term effect of lowering the minimum purchase age for alcohol from age 20 to age 18 years on alcohol-involved crashes in New Zealand. Methods. We modeled ratios of drivers in alcohol-involved crashes to drivers in non–alcohol-involved crashes by age group in 3 time periods using logistic regression, controlling for gender and adjusting for multiple comparisons. Results. Before the law change, drivers aged 18 to 19 and 20 to 24 years had similar odds of an alcohol-involved crash (P = .1). Directly following the law change, drivers aged 18 to 19 years had a 15% higher odds of being in an alcohol-involved crash than did drivers aged 20 to 24 years (P = .038). In the long term, drivers aged 18 to 19 years had 21% higher odds of an alcohol-involved crash than did the age control group (P ≤ .001). We found no effects for fatal alcohol-involved crashes alone and no trickle-down effects for the youngest group. Conclusions. Lowering the purchase age for alcohol was associated with a long-term impact on alcohol-involved crashes among drivers aged 18 to 19 years. Raising the minimum purchase age for alcohol would be appropriate. PMID:24825211
Ebel, B E; Mack, C; Diehr, P; Rivara, F P
2004-10-01
In 2001, 6.3 million passengers were involved in motor vehicle crashes. This study aimed to determine the number of work days lost as a result of motor vehicle crashes and factors that influenced people's return to work. This was a retrospective, population based cohort study of occupants in motor vehicles involved in crashes from the 1993-2001 Crashworthiness Data System produced by the National Highway Traffic Safety Administration. The sample population of people aged 18-65 years included two groups: occupants who survived and were working before the crash and occupants who were injured fatally and were estimated to have been working before the crash. Multivariate linear regression was used to analyze the impact of restraint use and injury type on return to work. Overall, 30.1% of occupants of vehicles that crashed missed one or more days of work. A crash resulted in a mean 28.0 (95% confidence interval 15.8 to 40.1) days lost from work, including losses associated with fatalities. The 2.1 million working occupants of vehicles that crashed in 2001 lost a total of 60 million days of work, resulting in annual productivity losses of over $7.5 billion (2964 to 12 075). Unrestrained vehicle occupants accounted for $5.6 billion in lost productivity. Motor vehicle crashes result in large and potentially preventable productive losses that are mostly attributable to fatal injuries.
Hot-air balloon tours: crash epidemiology in the United States, 2000-2011.
Ballard, Sarah-Blythe; Beaty, Leland P; Baker, Susan P
2013-11-01
Hot-air balloon tours are FAR Part 91-governed balloon rides conducted for compensation or hire. Part 91, General Aviation, in general involves the least strict federal regulations and accounts for the majority of aviation crashes and fatalities. National Transportation Safety Board reports of hot-air balloon tour crashes in the United States from 2000 through 2011 were read and analyzed. During the 12-yr period, 78 hot-air balloon tours crashed, involving 518 occupants. There were 91 serious injuries and 5 fatalities; 83% of crashes resulted in one or more serious or fatal outcomes. Of the serious injuries characterized, 56% were lower extremity fractures. Most crashes (81%) occurred during landing; 65% involved hard landings. Fixed object collisions contributed to 50% of serious injuries and all 5 fatalities. During landing sequences, gondola dragging, tipping, bouncing, and occupant ejection were associated with poor outcomes. Of the crashes resulting in serious or fatal outcomes, 20% of balloons were significantly damaged or destroyed. The incidence of morbidity and mortality is high among hot-air balloon tour crashes, and the proportion of balloon crashes attributed to paid rides appears to have increased over time. In addition to examining the role of restraint systems, personal protective equipment, and power line emergency procedures in ballooning, injury prevention efforts should target factors such hard landings, object strikes, gondola instability, and occupant ejections, which are associated with balloon injuries and deaths. Crash outcomes may also improve with vehicle engineering that enables balloons themselves to absorb impact forces.
Crash fatality risk and unibody versus body-on-frame structure in SUVs.
Ossiander, Eric M; Koepsell, Thomas D; McKnight, Barbara
2014-09-01
In crashes between cars and SUVs, car occupants are more likely to be killed than if they crashed with another car. An increasing proportion of SUVs are built with unibody, rather than truck-like body-on-frame construction. Unibody SUVs are generally lighter, less stiff, and less likely to roll over than body-on-frame SUVs, but whether unibody structure affects risk of death in crashes is unknown. To determine whether unibody SUVs differ from body-on-frame SUVs in the danger they pose to occupants of other vehicles and in the self-protection they offer to their own occupants. Case-control study of crashes between one compact SUV and one other passenger vehicle in the US during 1995-2008, in which the SUV was model year 1996-2006. Cases were all decedents in fatal crashes, one control was selected from each non-fatal crash. Occupants of passenger vehicles that crashed with compact unibody SUVs were at 18% lower risk of death compared to those that crashed with compact body-on-frame SUVs (adjusted odds ratio 0.82 (95% confidence interval 0.73-0.94)). Occupants of compact unibody SUVs were also at lower risk of death compared to occupants of body-on-frame SUVs (0.86 (0.72-1.02)). In two-vehicle collisions involving compact SUVs, unibody structure was associated with lower risk of death both in occupants of other vehicles in the crash, and in SUVs' own occupants. Copyright © 2014 Elsevier Ltd. All rights reserved.
Weaver, Ashley A; Gayzik, F Scott; Stitzel, Joel D
2009-01-01
Pulmonary contusion is the most common thoracic soft tissue injury encountered in motor vehicle crashes and is seen in 10-17% of all trauma admissions. This study presents a biomechanical and radiological analysis with the goal of quantifying pulmonary contusion resulting from motor vehicle crashes in order to illustrate the relationships between crash characteristics, contusion severity, and patient outcome. The 20 patients selected for this study were involved in motor vehicle crashes and subsequently enrolled in the Crash Injury and Research Engineering Network (CIREN) program at Wake Forest University Baptist Medical Center. Demographic data, sustained injuries, and crash characteristics were obtained through medical records and the CIREN database for all patients in the study. For each patient, the first chest computed tomography (CT) scan following the crash was segmented using a semi-automated approach to obtain volumes of trapped air, total lung, healthy lung, and high attenuation lung representing contused tissue. Three-dimensional models of the healthy and contused lung tissue were created for each patient. Rib fractures were present in 75% of patients and a substantial proportion of patients with pulmonary contusion injuries were involved in near side collisions. The near side door was identified as the most commonly involved component in pulmonary contusion injuries. The methodology and analysis presented in this study between crash characteristics, pulmonary contusion severity, and patient outcome are data that may contribute to future improvements in motor vehicle safety.
Evaluation of a policy to reduce youth tractor crashes on public roads.
Marlenga, B; Doty, B C; Berg, R L; Linneman, J G
2006-02-01
Evaluate the effectiveness of a United States state law, Wisconsin Act 455, in reducing highway tractor crashes involving youth operators. Policy outcome evaluation involving review of a retrospective case series. Youth highway tractor crashes from Wisconsin for the years 1994-2003 that resulted in a fatality, injury, and/or property damage. One hundred and forty six tractor crash cases involving operators younger than 16 years. Describe and model the tractor crash patterns before and after enactment of the law, and examine the relation between the contributing circumstances identified in the crash reports and the content covered in the mandated tractor certification course. There was neither a significant change in the number of youth tractor crashes after the law was passed, nor any reduction in the proportion of crashes where the youth operator was designated at fault. The tractor certification course did not cover the major factors contributing to youth tractor crashes on public roads. No significant effect of the law was detected and crash rates at the end of the study period were similar to those before Wisconsin Act 455. The authors'findings should not be construed to suggest that public policy, in general, is an ineffective strategy for the prevention of pediatric agricultural injuries. Negotiating a balance in public policy debates will be a challenge, but it is clear that future policy initiatives need to identify and implement the right policy for the right problem.
Factors associated with pilot fatalities in work-related aircraft crashes--Alaska, 1990-1999.
2002-04-26
Despite its large geographic area, Alaska has only 12,200 miles of public roads, and 90% of the state's communities are not connected to a highway system. Commuter and air-taxi flights are essential for transportation of passengers and delivery of goods, services, and mail to outlying communities (Figure 1). Because of the substantial progress in decreasing fatalities in the fishing and logging industries, aviation crashes are the leading cause of occupational death in Alaska. During 1990-1999, aircraft crashes in Alaska caused 107 deaths among workers classified as civilian pilots. This is equivalent to 410 fatalities per 100,000 pilots each year, approximately five times the death rate for all U.S. pilots and approximately 100 times the death rate for all U.S. workers. As part of a collaborative aviation safety initiative that CDC's National Institute for Occupational Safety and Health (NIOSH) is implementing with the Federal Aviation Administration (FAA), the National Transportation Safety Board (NTSB), and the National Weather Service, CDC analyzed data from NTSB crash reports to determine factors associated with pilot fatalities in work-related aviation crashes in Alaska. This report summarizes the result of this analysis, which found that the following factors were associated with pilot fatalities: crashes involving a post-crash fire, flights in darkness or weather conditions requiring instrument use, crashes occurring away from an airport, and crashes in which the pilot was not using a shoulder restraint. Additional pilot training, improved fuel systems that are less likely to ignite in crashes, and company policies that discourage flying in poor weather conditions might help decrease pilot fatalities. More detailed analyses of crash data, collaborations with aircraft operators to improve safety, and evaluation of new technologies are needed.
Sleep quality and motor vehicle crashes in adolescents.
Pizza, Fabio; Contardi, Sara; Antognini, Alessandro Baldi; Zagoraiou, Maroussa; Borrotti, Matteo; Mostacci, Barbara; Mondini, Susanna; Cirignotta, Fabio
2010-02-15
Sleep-related complaints are common in adolescents, but their impact on the rate of motor vehicle crashes accidents is poorly known. We studied subjective sleep quality, driving habits, and self-reported car crashes in high-school adolescents. Self-administered questionnaires (with items exploring driving habits) were distributed to 339 students who had a driver's license and attended 1 of 7 high schools in Bologna, Italy. Statistical analysis were performed to describe lifestyle habits, sleep quality, sleepiness, and their relationship with the binary dependent variable (presence or absence of car crashes) to identify the factors significantly affecting the probability of car crashes in a multivariate binary logistic regression model. Nineteen percent of the sample reported bad sleep, 64% complained of daytime sleepiness, and 40% reported sleepiness while driving. Eighty students (24%), 76% of which were males, reported that they had already crashed at least once, and 15% considered sleepiness to have been the main cause of their crash. As compared with adolescents who had not had a crash, those who had at least 1 previous crash reported that they more frequently used to drive (79% vs 62%), drove at night (25% vs 9%), drove while sleepy (56% vs 35%), had bad sleep (29% vs 16%), and used stimulants such as caffeinated soft drinks (32% vs 19%), tobacco (54% vs 27%), and drugs (21% vs 7%). The logistic procedure established a significant predictive role of male sex (p < 0.0001; odds ratio = 3.3), tobacco use (p < 0.0001; odds ratio = 3.2), sleepiness while driving (p = 0.010; odds ratio = 2.1), and bad sleep (p = 0.047; odds ratio = 1.9) for the crash risk. Our results confirm the high prevalence of sleep-related complaints among adolescents and highlight their independent role on self-reported crash risk.
Cai, Qing; Abdel-Aty, Mohamed; Lee, Jaeyoung
2017-10-01
This study aims at contributing to the literature on pedestrian and bicyclist safety by building on the conventional count regression models to explore exogenous factors affecting pedestrian and bicyclist crashes at the macroscopic level. In the traditional count models, effects of exogenous factors on non-motorist crashes were investigated directly. However, the vulnerable road users' crashes are collisions between vehicles and non-motorists. Thus, the exogenous factors can affect the non-motorist crashes through the non-motorists and vehicle drivers. To accommodate for the potentially different impact of exogenous factors we convert the non-motorist crash counts as the product of total crash counts and proportion of non-motorist crashes and formulate a joint model of the negative binomial (NB) model and the logit model to deal with the two parts, respectively. The formulated joint model is estimated using non-motorist crash data based on the Traffic Analysis Districts (TADs) in Florida. Meanwhile, the traditional NB model is also estimated and compared with the joint model. The result indicates that the joint model provides better data fit and can identify more significant variables. Subsequently, a novel joint screening method is suggested based on the proposed model to identify hot zones for non-motorist crashes. The hot zones of non-motorist crashes are identified and divided into three types: hot zones with more dangerous driving environment only, hot zones with more hazardous walking and cycling conditions only, and hot zones with both. It is expected that the joint model and screening method can help decision makers, transportation officials, and community planners to make more efficient treatments to proactively improve pedestrian and bicyclist safety. Published by Elsevier Ltd.
Saha, Dibakar; Alluri, Priyanka; Gan, Albert; Wu, Wanyang
2018-02-21
The objective of this study was to investigate the relationship between bicycle crash frequency and their contributing factors at the census block group level in Florida, USA. Crashes aggregated over the census block groups tend to be clustered (i.e., spatially dependent) rather than randomly distributed. To account for the effect of spatial dependence across the census block groups, the class of conditional autoregressive (CAR) models were employed within the hierarchical Bayesian framework. Based on four years (2011-2014) of crash data, total and fatal-and-severe injury bicycle crash frequencies were modeled as a function of a large number of variables representing demographic and socio-economic characteristics, roadway infrastructure and traffic characteristics, and bicycle activity characteristics. This study explored and compared the performance of two CAR models, namely the Besag's model and the Leroux's model, in crash prediction. The Besag's models, which differ from the Leroux's models by the structure of how spatial autocorrelation are specified in the models, were found to fit the data better. A 95% Bayesian credible interval was selected to identify the variables that had credible impact on bicycle crashes. A total of 21 variables were found to be credible in the total crash model, while 18 variables were found to be credible in the fatal-and-severe injury crash model. Population, daily vehicle miles traveled, age cohorts, household automobile ownership, density of urban roads by functional class, bicycle trip miles, and bicycle trip intensity had positive effects in both the total and fatal-and-severe crash models. Educational attainment variables, truck percentage, and density of rural roads by functional class were found to be negatively associated with both total and fatal-and-severe bicycle crash frequencies. Published by Elsevier Ltd.
Life-threatening motor vehicle crashes in bright sunlight
Redelmeier, Donald A.; Raza, Sheharyar
2017-01-01
Abstract Bright sunlight may create visual illusions that lead to driver error, including fallible distance judgment from aerial perspective. We tested whether the risk of a life-threatening motor vehicle crash was increased when driving in bright sunlight. This longitudinal, case-only, paired-comparison analysis evaluated patients hospitalized because of a motor vehicle crash between January 1, 1995 and December 31, 2014. The relative risk of a crash associated with bright sunlight was estimated by evaluating the prevailing weather at the time and place of the crash compared with the weather at the same hour and location on control days a week earlier and a week later. The majority of patients (n = 6962) were injured during daylight hours and bright sunlight was the most common weather condition at the time and place of the crash. The risk of a life-threatening crash was 16% higher during bright sunlight than normal weather (95% confidence interval: 9–24, P < 0.001). The increased risk was accentuated in the early afternoon, disappeared at night, extended to patients with different characteristics, involved crashes with diverse features, not apparent with cloudy weather, and contributed to about 5000 additional patient-days in hospital. The increased risk extended to patients with high crash severity as indicated by ambulance involvement, surgical procedures, length of hospital stay, intensive care unit admission, and patient mortality. The increased risk was not easily attributed to differences in alcohol consumption, driving distances, or anomalies of adverse weather. Bright sunlight is associated with an increased risk of a life-threatening motor vehicle crash. An awareness of this risk might inform driver education, trauma staffing, and safety warnings to prevent a life-threatening motor vehicle crash. Level of evidence: Epidemiologic Study, level III. PMID:28072708
Tavakoli Kashani, Ali; Rabieyan, Rahim; Besharati, Mohammad Mehdi
2016-01-01
Abstract: Background: In Iran more than 25% of crash fatalities belong to motorcycle operators and passengers in the recent years, from which about 20% are related to passenger fatalities. Methods: The aim of this study was to investigate the motorcycle operator and passenger characteristics as well as other contributory factors that may affect the fatality risk of motorcyclists involved in traffic crashes. To this end, motorcycle crash data between 2009 and 2012 was extracted from Iran traffic crash database and a logistic regression analysis was performed to obtain odds ratio estimates for each of the study variables. Results: The fatality risk of motorcyclists has a direct relationship with the number of pillion passengers carried. Results also indicate that the amount of increase in the likelihood of having a fatality in a motorcycles crash is considerably higher when the operator is accompanied by a male passenger of the same age. Furthermore, results showed that if the crash is occurred in the darkness, on curves, in rural areas and on highways, then the crash would be more likely to be fatal. Moreover, the head-on collisions, older operators, unlicensed operators and not using a safety helmet were found to increase the likelihood of a fatality in a motorcycle crash. Conclusions: Preventative measures such as, imposing stricter rules regarding safety helmet usage and confining the number of pillion passengers to one, might be implemented to reduce the fatality risk in motorcycle crashes. In addition, more appropriate infrastructures for penalizing offending motorcyclists could also reduce the frequency of law violations such as not wearing helmet or riding without motorcycle license, which in turn, would result into a reduction in the fatality risk of motorcycle crashes. PMID:26420217
Development of a frontal small overlap crashworthiness evaluation test.
Sherwood, Christopher P; Mueller, Becky C; Nolan, Joseph M; Zuby, David S; Lund, Adrian K
2013-01-01
Small overlap frontal crashes are those in which crash forces are applied outboard of the vehicle's longitudinal frame rails. In-depth analyses of crashes indicate that such crashes account for a significant proportion of frontal crashes with seriously injured occupants. The objective of this research was to evaluate possible barrier crash tests that could be used to evaluate the crashworthiness of vehicles across a spectrum of small overlap crash types. Sixteen full-scale vehicle tests were conducted using 3 midsize passenger vehicles in up to 6 different test configurations, including vehicle-to-vehicle and barrier tests. All vehicles were tested at 64 km/h with an instrumented Hybrid III midsize male driver dummy. All test configurations resulted in primary loading of the wheel, suspension system, and hinge pillar. Vehicles underwent substantial lateral movement during the crash, which varied by crash configuration. The occupant compartments had significant intrusion, particularly to the most outboard structures. Inboard movement of the steering wheel in combination with outboard movement of the dummies (due to the lateral vehicle motion) caused limited interaction with the frontal air bag in most cases. When assessing overall crashworthiness (based on injury measures, structural deformation, and occupant kinematics), one vehicle had superior performance in each crash configuration. This was confirmation that the countermeasures benefiting performance in a single small overlap test also will provide a benefit in other crash configurations. Based on these test results, the Insurance Institute for Highway Safety has developed a small overlap crashworthiness evaluation with the following characteristics: a rigid flat barrier with a 150-mm corner radius, 25 percent overlap, 64 km/h test speed, and a Hybrid III midsize male driver dummy.
Life-threatening motor vehicle crashes in bright sunlight.
Redelmeier, Donald A; Raza, Sheharyar
2017-01-01
Bright sunlight may create visual illusions that lead to driver error, including fallible distance judgment from aerial perspective. We tested whether the risk of a life-threatening motor vehicle crash was increased when driving in bright sunlight.This longitudinal, case-only, paired-comparison analysis evaluated patients hospitalized because of a motor vehicle crash between January 1, 1995 and December 31, 2014. The relative risk of a crash associated with bright sunlight was estimated by evaluating the prevailing weather at the time and place of the crash compared with the weather at the same hour and location on control days a week earlier and a week later.The majority of patients (n = 6962) were injured during daylight hours and bright sunlight was the most common weather condition at the time and place of the crash. The risk of a life-threatening crash was 16% higher during bright sunlight than normal weather (95% confidence interval: 9-24, P < 0.001). The increased risk was accentuated in the early afternoon, disappeared at night, extended to patients with different characteristics, involved crashes with diverse features, not apparent with cloudy weather, and contributed to about 5000 additional patient-days in hospital. The increased risk extended to patients with high crash severity as indicated by ambulance involvement, surgical procedures, length of hospital stay, intensive care unit admission, and patient mortality. The increased risk was not easily attributed to differences in alcohol consumption, driving distances, or anomalies of adverse weather.Bright sunlight is associated with an increased risk of a life-threatening motor vehicle crash. An awareness of this risk might inform driver education, trauma staffing, and safety warnings to prevent a life-threatening motor vehicle crash. Epidemiologic Study, level III.
Mahajan, Narinder; Aggarwal, Meenu; Raina, Sunil; Verma, Lekh Raj; Mazta, Salig Ram; Gupta, B P
2013-01-01
Research Question: What are the various injuries in road traffic crash cases? Objectives: To study various non-fatal injuries in road traffic crash cases. Study Design: Hospital based Descriptive study. Study Population: The study population comprised of 401 consecutive cases of non- fatal injuries involved in road traffic crashes and reported at Indira Gandhi Medical College hospital, Shimla. Study Period: 1st June 2005 to 31st May 2006. Study Variables: Demographic characteristics of the victims, pattern of injuries and hospital stay of the victims. Types of crashes, time, day and month of crashes, vehicles involved in crashes, use of protective gear etc. Statistical Analysis: Percentages, Proportions. Results: 73% of the injured victims were young between 20-49yrs, male to female ratio being 5.3:1. Employees (34.7%) and occupants of transport vehicles (45.9%) constituted the maximum number of the victims. Major injuries (fractures and abd. injuries) were reported in 53.4% of the victims and fractures of lower limb were the commonest of the injuries (26.3%). Use of seat-belt was found to be alarmingly low (14.3%) amongst the four- wheeler users and its non-use was found to be significantly associated with the major injuries. Helmet was used by 36 cases (66.7%) out of total of 54 users of motorized two-wheelers at the time of crash. Human error was the most reported cause of crash (82%) and the most common mode of crash was skidding and/rolling down (55%).23.1% of the drivers were reported to have consumed alcohol at the time of crash. PMID:24404456
Using data mining techniques to predict the severity of bicycle crashes.
Prati, Gabriele; Pietrantoni, Luca; Fraboni, Federico
2017-04-01
To investigate the factors predicting severity of bicycle crashes in Italy, we used an observational study of official statistics. We applied two of the most widely used data mining techniques, CHAID decision tree technique and Bayesian network analysis. We used data provided by the Italian National Institute of Statistics on road crashes that occurred on the Italian road network during the period ranging from 2011 to 2013. In the present study, the dataset contains information about road crashes occurred on the Italian road network during the period ranging from 2011 to 2013. We extracted 49,621 road accidents where at least one cyclist was injured or killed from the original database that comprised a total of 575,093 road accidents. CHAID decision tree technique was employed to establish the relationship between severity of bicycle crashes and factors related to crash characteristics (type of collision and opponent vehicle), infrastructure characteristics (type of carriageway, road type, road signage, pavement type, and type of road segment), cyclists (gender and age), and environmental factors (time of the day, day of the week, month, pavement condition, and weather). CHAID analysis revealed that the most important predictors were, in decreasing order of importance, road type (0.30), crash type (0.24), age of cyclist (0.19), road signage (0.08), gender of cyclist (0.07), type of opponent vehicle (0.05), month (0.04), and type of road segment (0.02). These eight most important predictors of the severity of bicycle crashes were included as predictors of the target (i.e., severity of bicycle crashes) in Bayesian network analysis. Bayesian network analysis identified crash type (0.31), road type (0.19), and type of opponent vehicle (0.18) as the most important predictors of severity of bicycle crashes. Copyright © 2017 Elsevier Ltd. All rights reserved.
Wu, Kun-Feng; Aguero-Valverde, Jonathan; Jovanis, Paul P
2014-11-01
There has been considerable research conducted over the last 40 years using traffic safety-related events to support road safety analyses. Dating back to traffic conflict studies from the 1960s these observational studies of driver behavior have been criticized due to: poor quality data; lack of available and useful exposure measures linked to the observations; the incomparability of self-reported safety-related events; and, the difficulty in assessing culpability for safety-related events. This study seeks to explore the relationships between driver characteristics and traffic safety-related events, and between traffic safety-related events and crash involvement while mitigating some of those limitations. The Virginia Tech Transportation Institute 100-Car Naturalistic Driving Study dataset, in which the participants' vehicles were instrumented with various cameras and sensors during the study period, was used for this study. The study data set includes 90 drivers observed for 12-13 months driving. This study focuses on single vehicle run-off-road safety-related events only, including 14 crashes and 182 safety-related events (30 near crashes, and 152 crash-relevant incidents). Among the findings are: (1) drivers under age 25 are significantly more likely to be involved in safety-related events and crashes; and (2) significantly positive correlations exist between crashes, near crashes, and crash-relevant incidents. Although there is still much to learn about the factors affecting the positive correlation between safety-related events and crashes, a Bayesian multivariate Poisson log-normal model is shown to be useful to quantify the associations between safety-related events and crash risk while controlling for driver characteristics. Copyright © 2014 Elsevier Ltd. All rights reserved.
Ballard, Sarah-Blythe; Osorio, Victor B
2015-01-01
This study provides new public health data about U.S. civil air shows. Risk factors for fatalities in civil air show crashes were analyzed. The value of the FIA score in predicting fatal outcomes was evaluated. With the use of the FAA's General Aviation and Air Taxi Survey and the National Transportation Safety Board's data, the incidence of civil air show crashes from 1993 to 2013 was calculated. Fatality risk factors for crashes were analyzed by means of regression methods. The FIA index was validated to predict fatal outcomes by using the factors of fire, instrument conditions, and away-from-airport location, and was evaluated through receiver operating characteristic (ROC) curves. The civil air show crash rate was 31 crashes per 1,000 civil air events. Of the 174 civil air show crashes that occurred during the study period, 91 (52%) involved at least one fatality; on average, 1.1 people died per fatal crash. Fatalities were associated with four major risk factors: fire [adjusted odds ratio (AOR) = 7.1, 95% confidence interval (CI) = 2.4 to 20.6, P < .001], pilot error (AOR = 5.2, 95% CI = 1.8 to 14.5, P = .002), aerobatic flight (AOR = 3.6, 95% CI = 1.6 to 8.2, P = .002), and off-airport location (AOR = 3.4, 95% CI = 1.5 to 7.5, P = .003). The area under the FIA score's ROC curve was 0.71 (95% CI = 0.64 to 0.78). Civil air show crashes were marked by a high risk of fatal outcomes to pilots in aerobatic performances but rare mass casualties. The FIA score was not a valid measurement of fatal risk in civil air show crashes.
Characteristics of crashes with farm equipment that increase potential for injury.
Peek-Asa, Corinne; Sprince, Nancy L; Whitten, Paul S; Falb, Scott R; Madsen, Murray D; Zwerling, Craig
2007-01-01
Crash fatality and injury rates are higher on rural roadways than other roadway types. Although slow-moving farm vehicles and equipment are risk factors on rural roads, little is known about the characteristics of crashes with farm vehicles/equipment. To describe crashes and injuries for the drivers of farm vehicles/equipment and non-farm vehicles involved in an injury crash. Passengers are not included in this analysis. Injury crashes were included that involved a farm vehicle/equipment and at least one non-farm vehicle reported in Iowa Department of Transportation crash data from 1995 to 2004. Odds ratios were calculated through logistic regression to identify increased odds for injury among drivers of non-farm vehicles and farm vehicles/equipment. We examined frequently occurring crash characteristics to identify crash scenarios leading to the highest odds for injury. Non-farm vehicle drivers were 5.23 times more likely to be injured than farm vehicle/equipment drivers (95% CI = 4.12-6.46). The absence of restraint use was a significant predictor of injury for both farm vehicle/equipment drivers (OR = 2.85; 95% CI = 1.14-7.13) and non-farm vehicle drivers (OR = 2.53; 95% CI = 1.54-4.15). Crash characteristics increasing the odds of injury for non-farm vehicle drivers included speeding, passing the farm vehicle/equipment, driving on a county road, having a frontal impact collision, and crashing in darkness. Ejection was the strongest predictor of injury for the farm vehicle/equipment driver. Non-farm vehicle drivers were much more likely to be injured than farm vehicle/equipment drivers, suggesting that farm vehicle/equipment crash prevention should be a priority for all rural road users. Prevention strategies that reduce motor vehicle speed, assist in safe passing, increase seat belt use, and increase conspicuousness of the farm vehicle/equipment are suggested.
Wilson, Suzanne J; Begg, Dorothy J; Samaranayaka, Ari
2012-11-01
Linking hospital discharge and police traffic crash records has been used to provide information on causes and outcomes for hospitalised traffic crash cases. Motorcyclists are particularly vulnerable to injury in a traffic crash, but no published linkage studies have reported in detail on this road user group. The present study examined motorcycle traffic crash injury cases in New Zealand in 2000-2004 by probabilistically linking national hospital discharge records with police traffic crash reports. Injury cases had to have spent at least one night in hospital before being discharged and were defined as serious or moderate based on their International Classification of Disease Injury Severity Scores (ICISS). Despite a robust linkage process, only 46% of cases could be linked to a police record; 60% of the serious injuries and 41% of the moderate. The low linkage was most likely due to under-reporting of crashes to or by the police. While moderate injury cases were expected to be under-reported, the level of under-reporting of cases with serious threat-to-life injuries is concerning. To assess whether the linked dataset could provide valid information on the crash circumstances and injury outcomes of hospitalised motorcycle crash cases, the characteristics of the linked and unlinked hospital discharge cases were compared using chi-square tests and multivariate logistic regression. Serious injury cases were less likely to be linked if only one vehicle was involved, or the injured riders and passengers were younger than 20 years or spent less than one week in hospital. For moderate injury cases, there were also differences in linkage by injured body region and crash month. While these discrepancies need to taken into consideration when interpreting results, the linked hospital-police dataset has the potential to provide insights into motorcycle crash circumstances and outcomes not otherwise obtainable. Copyright © 2011 Elsevier Ltd. All rights reserved.
Crash protectiveness to occupant injury and vehicle damage: An investigation on major car brands.
Huang, Helai; Li, Chunyang; Zeng, Qiang
2016-01-01
This study sets out to investigate vehicles' crash protectiveness on occupant injury and vehicle damage, which can be deemed as an extension of the traditional crash worthiness. A Bayesian bivariate hierarchical ordered logistic (BVHOL) model is developed to estimate the occupant protectiveness (OP) and vehicle protectiveness (VP) of 23 major car brands in Florida, with considering vehicles' crash aggressivity and controlling external factors. The proposed model not only takes over the strength of the existing hierarchical ordered logistic (HOL) model, i.e. specifying the order characteristics of crash outcomes and cross-crash heterogeneities, but also accounts for the correlation between the two crash responses, driver injury and vehicle damage. A total of 7335 two-vehicle-crash records with 14,670 cars involved in Florida are used for the investigation. From the estimation results, it's found that most of the luxury cars such as Cadillac, Volvo and Lexus possess excellent OP and VP while some brands such as KIA and Saturn perform very badly in both aspects. The ranks of the estimated safety performance indices are even compared to the counterparts in Huang et al. study [Huang, H., Hu, S., Abdel-Aty, M., 2014. Indexing crash worthiness and crash aggressivity by major car brands. Safety Science 62, 339-347]. The results show that the rank of occupant protectiveness index (OPI) is relatively coherent with that of crash worthiness index, but the ranks of crash aggressivity index in both studies is more different from each other. Meanwhile, a great discrepancy between the OPI rank and that of vehicle protectiveness index is found. What's more, the results of control variables and hyper-parameters estimation as well as comparison to HOL models with separate or identical threshold errors, demonstrate the validity and advancement of the proposed model and the robustness of the estimated OP and VP. Copyright © 2015 Elsevier Ltd. All rights reserved.
Explaining reduction of pedestrian-motor vehicle crashes in Arkhangelsk, Russia, in 2005-2010.
Kudryavtsev, Alexander V; Nilssen, Odd; Lund, Johan; Grjibovski, Andrej M; Ytterstad, Børge
2012-01-01
To explain a reduction in pedestrian-motor vehicle crashes in Arkhangelsk, Russia, in 2005-2010. Retrospective ecological study. For 2005-2010, police data on pedestrian-motor vehicle crashes, traffic violations, and total motor vehicles (MVs) were combined with data on changes in national road traffic legislation and municipal road infrastructure. Negative binomial regression was used to investigate trends in monthly rates of pedestrian-motor vehicle crashes per total MVs and estimate changes in these rates per unit changes in the safety measures. During the 6 years, the police registered 2,565 pedestrian-motor vehicle crashes: 1,597 (62%) outside crosswalks, 766 (30%) on non-signalized crosswalks, and 202 (8%) on signalized crosswalks. Crash rates outside crosswalks and on signalized crosswalks decreased on average by 1.1% per month, whereas the crash rate on non-signalized crosswalks remained unchanged. Numbers of signalized and non-signalized crosswalks increased by 14 and 19%, respectively. Also, 10% of non-signalized crosswalks were combined with speed humps, and 4% with light-reflecting vertical signs. Pedestrian penalties for traffic violations increased 4-fold. Driver penalties for ignoring prohibiting signal and failure to give way to pedestrian on non-signalized crosswalk increased 7- and 8-fold, respectively. The rate of total registered drivers' traffic violations per total MVs decreased on average by 0.3% per month. All studied infrastructure and legislative measures had inverse associations with the rate of crashes outside crosswalks. The rate of crashes on signalized crosswalks showed inverse associations with related monetary penalties. The introduction of infrastructure and legislative measures is the most probable explanation of the reduction of pedestrian-motor vehicle crashes in Arkhangelsk. The overall reduction is due to decreases in rates of crashes outside crosswalks and on signalized crosswalks. No change was observed in the rate of crashes on non-signalized crosswalks.
Wang, Bo; Hallmark, Shauna; Savolainen, Peter; Dong, Jing
2017-12-01
Prior research has shown the probability of a crash occurring on horizontal curves to be significantly higher than on similar tangent segments, and a disproportionally higher number of curve-related crashes occurred in rural areas. Challenges arise when analyzing the safety of horizontal curves due to imprecision in integrating information as to the temporal and spatial characteristics of each crash with specific curves. The second Strategic Highway Research Program(SHRP 2) conducted a large-scale naturalistic driving study (NDS),which provides a unique opportunity to better understand the contributing factors leading to crash or near-crash events. This study utilizes high-resolution behavioral data from the NDS to identify factors associated with 108 safety critical events (i.e., crashes or near-crashes) on rural two-lane curves. A case-control approach is utilized wherein these events are compared to 216 normal, baseline-driving events. The variables examined in this study include driver demographic characteristics, details of the traffic environment and roadway geometry, as well as driver behaviors such as in-vehicle distractions. Logistic regression models are estimated to discern those factors affecting the likelihood of a driver being crash-involved. These factors include high-risk behaviors, such as speeding and visual distractions, as well as curve design elements and other roadway characteristics such as pavement surface conditions. This paper successfully integrated driver behavior, vehicle characteristics, and roadway environments into the same model. Logistic regression model was found to be an effective way to investigate crash risks using naturalistic driving data. This paper revealed a number of contributing factors to crashes on rural two-lane curves, which has important implications in traffic safety policy and curve geometry design. This paper also discussed limitations and lessons learned from working with the SHRP 2 NDS data. It will benefit future researchers who work with similar type of data. Copyright © 2017 National Safety Council and Elsevier Ltd. All rights reserved.
Cicchino, Jessica B
2017-02-01
The objective of this study was to evaluate the effectiveness of forward collision warning (FCW) alone, a low-speed autonomous emergency braking (AEB) system operational at speeds up to 19mph that does not warn the driver prior to braking, and FCW with AEB that operates at higher speeds in reducing front-to-rear crashes and injuries. Poisson regression was used to compare rates of police-reported crash involvements per insured vehicle year in 22 U.S. states during 2010-2014 between passenger vehicle models with FCW alone or with AEB and the same models where the optional systems were not purchased, controlling for other factors affecting crash risk. Similar analyses compared rates between Volvo 2011-2012 model S60 and 2010-2012 model XC60 vehicles with a standard low-speed AEB system to those of other luxury midsize cars and SUVs, respectively, without the system. FCW alone, low-speed AEB, and FCW with AEB reduced rear-end striking crash involvement rates by 27%, 43%, and 50%, respectively. Rates of rear-end striking crash involvements with injuries were reduced by 20%, 45%, and 56%, respectively, by FCW alone, low-speed AEB, and FCW with AEB, and rates of rear-end striking crash involvements with third-party injuries were reduced by 18%, 44%, and 59%, respectively. Reductions in rear-end striking crashes with third-party injuries were marginally significant for FCW alone, and all other reductions were statistically significant. FCW alone and low-speed AEB reduced rates of being rear struck in rear-end crashes by 13% and 12%, respectively, but FCW with AEB increased rates of rear-end struck crash involvements by 20%. Almost 1 million U.S. police-reported rear-end crashes in 2014 and more than 400,000 injuries in such crashes could have been prevented if all vehicles were equipped with FCW and AEB that perform similarly as systems did for study vehicles. Copyright © 2016 Elsevier Ltd. All rights reserved.
Effects of red light camera enforcement on fatal crashes in large U.S. cities.
Hu, Wen; McCartt, Anne T; Teoh, Eric R
2011-08-01
To estimate the effects of red light camera enforcement on per capita fatal crash rates at intersections with signal lights. From the 99 large U.S. cities with more than 200,000 residents in 2008, 14 cities were identified with red light camera enforcement programs for all of 2004-2008 but not at any time during 1992-1996, and 48 cities were identified without camera programs during either period. Analyses compared the citywide per capita rate of fatal red light running crashes and the citywide per capita rate of all fatal crashes at signalized intersections during the two study periods, and rate changes then were compared for cities with and without cameras programs. Poisson regression was used to model crash rates as a function of red light camera enforcement, land area, and population density. The average annual rate of fatal red light running crashes declined for both study groups, but the decline was larger for cities with red light camera enforcement programs than for cities without camera programs (35% vs. 14%). The average annual rate of all fatal crashes at signalized intersections decreased by 14% for cities with camera programs and increased slightly (2%) for cities without cameras. After controlling for population density and land area, the rate of fatal red light running crashes during 2004-2008 for cities with camera programs was an estimated 24% lower than what would have been expected without cameras. The rate of all fatal crashes at signalized intersections during 2004-2008 for cities with camera programs was an estimated 17% lower than what would have been expected without cameras. Red light camera enforcement programs were associated with a statistically significant reduction in the citywide rate of fatal red light running crashes and a smaller but still significant reduction in the rate of all fatal crashes at signalized intersections. The study adds to the large body of evidence that red light camera enforcement can prevent the most serious crashes. Communities seeking to reduce crashes at intersections should consider this evidence. Copyright © 2011 Elsevier Ltd. All rights reserved.
Impact of a graduated driver's license law on crashes involving young drivers in New York State.
Cheng, Julius D; Schubmehl, Heidi; Kahn, Steven A; Gestring, Mark L; Sangosanya, Ayodele; Stassen, Nicole A; Bankey, Paul E
2012-08-01
Motor vehicle crashes constitute the greatest risk of injury for young adults. Graduated driver licensing (GDL) laws have been used to reduce the number of injuries and deaths in the young driver population. The New York State GDL law increased supervision of young driver and limited both time-of-day driven and number of passengers. This review examines the impact of a GDL enacted in New York in September 2003. A retrospective review of New York State administrative databases from 2001 to 2009 was performed. During this period, a state-wide GDL requirement was implemented. Database review included all reported crashes to the New York State Department of Motor Vehicles by cause and driver age as well as motor fuel tax receipts by the New York State Comptroller's Office. Motor fuel tax receipts and consumption information were used as a proxy for overall miles driven. Before 2003, drivers younger than 18 years were involved in 90 fatal crashes and 10,406 personal-injury (PI) crashes, constituting 4.49% and 3.38% of all fatal and PI crashes in New York State, respectively. By 2009, the number of fatal and PI crashes involving drivers who are younger than 18 years decreased to 44 (2.87%) and 5,246 (2.24%), respectively. Of note, the number of crashes experienced by the age group 18 years to 20 years during this period also declined, from 192 (9.59% of all fatal crashes) and 25,407 (8.24% of all PI crashes) to 135 (8.81%) and 18,114 (7.73%), respectively. Overall numbers of crashes reported remained relatively stable, between 549,000 in 2001 and 520,000 in 2009. Motor fuel use during this period also declined, but to a lesser degree ($552 million to $516 million or 6.6%). The use of a GDL law in New York State has shown a large decrease in the number of fatalities and PI crashes involving young drivers. The delay in full driver privileges from the GDL did not result in an increase in fatal or PI crashes in the next older age group.
NASA Technical Reports Server (NTRS)
Burrows, Leroy T.
1993-01-01
During the 1960's over 30 full-scale aircraft crash tests were conducted by the Flight Safety Foundation under contract to the Aviation Applied Technology Directorate (AATD) of the U.S. Army Aviation Systems Command (AVSCOM). The purpose of these tests were to conduct crash injury investigations that would provide a basis for the formulation of sound crash resistance design criteria for light fixed-wing and rotary wing aircraft. This resulted in the Crash Survival Design Criteria Designer's Guide which was first published in 1967 and has been revised numerous times, the last being in 1989. Full-scale aircraft crash testing is an expensive way to investigate structural deformations of occupied spaces and to determine the decelerative loadings experienced by occupants in a crash. This gave initial impetus to the U.S. Army to develop analytical methods to predict the dynamic response of aircraft structures in a crash. It was believed that such analytical tools could be very useful in the preliminary design stage of a new helicopter system which is required to demonstrate a level of crash resistance and had to be more cost effective than full-scale crash tests or numerous component design support tests. From an economic point of view, it is more efficient to optimize for the incorporation of crash resistance features early in the design stage. However, during preliminary design it is doubtful if sufficient design details, which influence the exact plastic deformation shape of structural elements, will be available. The availability of simple procedures to predict energy absorption and load-deformation characteristics will allow the designer to initiate valuable cost, weight, and geometry tradeoff studies. The development of these procedures will require some testing of typical specimens. This testing should, as a minimum, verify the validity of proposed procedures for providing pertinent nonlinear load-deformation data. It was hoped that through the use of these analytical models, the designer could optimize aircraft design for crash resistance from both a weight and cost increment standpoint, thus enhancing the acceptance of the design criteria for crash resistance.
Koopmans, Joy M; Friedman, Lee; Kwon, Soyang; Sheehan, Karen
2015-04-01
Describe age-based urban pedestrian versus auto crash characteristics and identify crash characteristics associated with injury severity. Secondary analysis of the 2004-2010 National Highway and Traffic Safety Administration database for Illinois. All persons in Chicago crashes with age data who were listed as pedestrians (n=7175 child age ≤19 yo, n=16,398 adult age ≥20 yo) were included. Incidence and crash characteristics were analyzed by age groups and year. Main outcome measures were incidence, crash setting, and injury severity. Multivariate logistic regression analysis was performed to estimate injury severity by crash characteristics. Overall incidence was higher for child (146.6 per 100,000) versus adult (117.3 per 100,000) pedestrians but case fatality rate was lower (0.7% for children, 1.7% for adults). Child but not adult pedestrian injury incidence declined over time (trend test p<0.0001 for <5 yo, 5-9 yo, and 10-14 yo; p<0.05 for 15-19 yo, p=0.96 for ≥20 yo). Most crashes for both children and adults took place during optimal driving conditions. Injuries were more frequent during warmer months for younger age groups compared to older (χ(2)p<0.001). Midblock crashes increased as age decreased (p<0.0001 for trend). Most crashes occurred at sites with sub-optimal traffic controls but varied by age (p<0.0001 for trend). Crashes were more likely to be during daylight on dry roads in clear weather conditions for younger age groups compared to older (χ(2)p<0.001). Daylight was associated with less severe injury (child OR 0.93, 95% CI 0.87-0.98; adult OR 0.90, 95% CI 0.87-0.93). The incidence of urban pedestrian crashes declined over time for child subgroups but not for adults. The setting of pedestrian crashes in Chicago today varies by age but is similar to that seen in other urban locales previously. Injuries for all age groups tend to be less severe during daylight conditions. Age-based prevention efforts may prove beneficial. Copyright © 2015 Elsevier Ltd. All rights reserved.
Using medico-legal data to investigate fatal older road user crash circumstances and risk factors.
Koppel, Sjaan; Bugeja, Lyndal; Smith, Daisy; Lamb, Ashne; Dwyer, Jeremy; Fitzharris, Michael; Newstead, Stuart; D'Elia, Angelo; Charlton, Judith
2018-02-17
This study used medico-legal data to investigate fatal older road user (ORU, aged 65 years and older) crash circumstances and risk factors relating to 4 key components of the Safe System approach (e.g., roads and roadsides, vehicles, road users, and speeds) to identify areas of priority for targeted prevention activity. The Coroners' Court of Victoria's (CCOV) Surveillance Database was searched to identify and describe the frequency and rate per 100,000 population of fatal ORU crashes in the Australian state of Victoria for 2013-2014. Information relating to the deceased ORU, crash characteristics and circumstances, and risk factors was extracted and analyzed. One hundred and thirty-eight unintentional fatal ORU crashes were identified in the CCOV Surveillance Database. Of these fatal ORU crashes, most involved older drivers (44%), followed by older pedestrians (32%), older passengers (17%), older pedal cyclists (4%), older motorcyclists (1%), and older mobility scooter users (1%). The average annual rate of fatal ORU crashes per 100,000 population was 8.1 (95% confidence interval [CI], 6.0-10.2). In terms of the crash characteristics and circumstances, most fatal ORU crashes involved a counterpart (98%), of which the majority were passenger cars (50%) or fixed/stationary objects (25%), including trees (46%) or embankments (23%). In addition, most fatal ORU crashes occurred close to home (73%), on-road (87%), on roads that were paved (94%), on roads with light traffic volume (37%), and during low-risk conditions: between 12 p.m. and 6 p.m. (44%), on weekdays (80%), during daylight (75%), and under dry/clear conditions (81%). Road user (RU) error was identified by the police and/or the coroner for the majority of fatal crashes (55%), with a significant proportion of deceased ORUs deemed to have failed to yield (54%) or misjudged (41%). RU error was the most significant factor identified in fatal ORU crashes, which suggests that there is a limited capacity of the road system to fully accommodate RU errors. Initiatives related to safer roads and roadsides, vehicles, speed zones, as well as behavioral approaches are key areas of priority for targeted activity to prevent fatal ORU crashes in the future.