2013 Session: 673

• Crash Rates on Interstate Segments with Very Large Truck Percentages
  Abstract: Recent decades have seen substantial growth in freight miles traveled, due to globalization, trade growth, and improvements in logistics and supply chain management. Although these developments have led to economic growth, there has been sharp increase in the proportion of freight/truck traffic traveling along interstates routes that has created significant interactions between trucks and other vehicles. These interactions have raised safety and capacity concerns on the roadways. This paper develops a regression model that explores the relationship between percentage of trucks and crash rates on Interstate 80 segments in Wyoming and Nebraska where the truck percentages are very high (35 to 50%) while also accounting for the significant effects of weather in this region. The Wyoming monthly model indicates that the likelihood of crashes increases as the percentage trucks increases during wet road and winter conditions. The Nebraska monthly model also show that during severe (cold) weather conditions the effect of percentage of trucks on the crash rate increases.
  Authors: Offei, Edward; Young, Rhonda Kae; Wulff, Shaun S.
  Authors: Offei, Edward; Young, Rhonda Kae; Wulff, Shaun S.
  Year: 2013
  Document Type: Paper
  Subject: Motor Carriers; Safety and Human Factors
  Session: 673
  Paper Number: 13-0982
• Investigating the Effect of Burnout on Accident Involvement in Occupational Drivers
  Abstract: The health and wellness management of occupational drivers requires cognizance of burnout as an occupational hazard. However, the literature is dominated by studies on stress rather than burnout. This study investigated the manner in which burnout may affect accident involvement in occupational drivers. Based on the transactional theory of stress, we propose a causal structure in which burnout mediates between occupational stress and accident involvement. We recruited 915 public transport drivers. The Copenhagen Burnout Inventory and Effort Reward Imbalance Scale were adopted to measure burnout and occupational stress, respectively. The results of the analysis showed that burnout exerted a direct effect on accident involvement beyond the effect of occupational stress. The enhancement of an organization¡¦s safety culture did not significantly reduce the effect of occupational stress on burnout; however, it significantly reduced the effect of burnout on accident involvement, and thus, indirectly alleviated the effect of occupational stress on accident involvement. In summary, burnout, as a comprehensive measure of the adverse effect of various types of chronic stressors, provides a strong indicator to identify drivers who constitute a risk for the organization and for road safety. The management of burnout should be incorporated into overall stress management. Occupational drivers normally experience a low level of autonomy and work long hours; thus, safety culture is crucial to this occupational category to reduce burnout and ensure workplace safety.
  Authors: Chung, Yi-Shih; Wu, Hui-Ling
  Authors: Chung, Yi-Shih; Wu, Hui-Ling
  Year: 2013
  Document Type: Paper
  Subject: Motor Carriers; Safety and Human Factors
  Session: 673
  Paper Number: 13-1278
• Characteristics and Contributory Causes Associated with Large-Truck Crashes and Countermeasures for Mitigation
  Abstract: Statistics show that the total number of registered large trucks and truck vehicle-miles traveled has increased in the last 10 years. As a result, their probability of involving in crashes also increases. This study identified the characteristics, factors associated with their occurrences, and the causes contributing to the increased severity of truck crashes in Kansas. Suitable countermeasure ideas were also identified to mitigate the number and severity of truck crashes. Various driver-, road-, environment- and vehicle- related characteristics and contributory causes were identified and analyzed. Driver-related causes were more common than any other type of contributory cause for the occurrence of truck-crashes. Failing to give enough time and attention, being too fast for existing conditions, and failing to yield right-of-way were the most dominant truck-driver-related contributory causes, among many others. Through the severity modeling, factors associated with increased severity of truck-crashes were identified. Truck-driver being trapped had the highest odds of contributing to a more severe truck-crash followed by the collision resulting in damage to the truck and truck-driver being under the influence of alcohol respectively.Intelligent countermeasure ideas along with some traditional practices followed to mitigate truck-crashes were identified. Automated Truck Rollover Warning Systems, Lane Drift Warning Systems (LDWS), Speed Limiters, and connecting vehicle technologies like Vehicle-to-Vehicle (V2V) integration systems were among the countermeasure ideas. Development and implementation of these countermeasures in a cost effective manner might help mitigate the number and severity of truck-crashes, thereby, improving overall safety of the highway system.
  Authors: Kotikalapudi, Siddhartha; Dissanayake, Sunanda
  Authors: Kotikalapudi, Siddhartha; Dissanayake, Sunanda
  Year: 2013
  Document Type: Paper
  Subject: Motor Carriers; Safety and Human Factors
  Session: 673
  Paper Number: 13-1368
• Stress During Driving for Novice Truck Drivers
  Abstract: This research aims to identify the sources of driving stress, study the nature of driving stress and define its relationship with stressors. The ultimate goal is to identify parameters that can be used as actuators by traffic engineers to control the driver stress level for truck drivers. To achieve these objectives, the data acquisition was done from adult novice truck drivers participating in truck driving training. The data analysis showed two distinct clusters of stress categorized as “Low Stress Level” and “High Stress Level”. The binary logistic model was used to identify the events that significantly changed the probability of a driver being in high stress level. 13 parameters were found to be statistically significant in altering the stress level. The truck driving training sessions were found useful in lowering the stress. The driver’s predisposition to the stress like Trait Anxiety score and State Anxiety score were found statistically significant. The right turn maneuvers, the presence of STOP as control, passive overtaking, coaxial acceleration and lateral velocity significantly impacted the stress levels. Similarly, the road types: collector and minor arterial and the time elapsed from start to the instant of driving were also found significant. In conclusion, the study identified three main handles that can be used by traffic engineers for reducing the driver stress level for truck drivers: i) truck driver training, ii) level of service of segments and improvement of intersection in terms of geometry and traffic control and iii) the avoidance of long continuous driving.
  Authors: Gyawali, Sunil; Sharma, Anuj
  Authors: Gyawali, Sunil; Sharma, Anuj
  Year: 2013
  Document Type: Paper
  Subject: Motor Carriers; Safety and Human Factors
  Session: 673
  Paper Number: 13-1510
• Linking Carrier Descriptive Attributes to Crash Patterns: Untapped Tool in State Motor Carrier Safety Improvement Programs
  Abstract: Using data from Virginia and North Carolina as a pilot study, this paper explores a set of issues and questions that are believed to be national in scope. To do so, descriptive attributes of motor carriers that were involved in combination-unit truck fatal crashes in North Carolina and Virginia from 2005-2009 have been characterized. Historically, the classic paradigm for studying underlying crash causes has been to focus on driver, vehicle, and highway- and environment-related factors to identify reoccurring or prevalent patterns. There is another, untapped data source, however: data from the Federal Motor Carrier Safety Administration’s (FMCSA) Motor Carrier Identification Report, MCS-150. All motor carriers that register with FMCSA are required to complete this form to be able to operate in interstate commerce and obtain a United States Department of Transportation (USDOT) number. This study linked MCS-150 data with crash data files to add carrier attribute/descriptive information to the list of underlying risk factors that can be studied. Off the Interstates, the fleet size of the carriers was smaller, more of them were domiciled in the state in which the crash occurred, more private and exempt carriers were involved and, in many cases, the crash occurred very close to the carrier’s place of business. For crashes on the Interstates, the carriers tended to be larger, were more likely to be a for-hire carrier located in other states, and had traveled greater distances from their business location before the crash occurred. The crash pattern differences of small carriers (10 or fewer vehicles operated) were the same, but more pronounced compared to the patterns associated with carriers of all fleet sizes. In both states, crash patterns reflected mileage accumulation patterns on the two road types. The results suggest that small local/regional carriers face higher risks and safety challenges due to the highway environments in which they operate and that new ways to assist them be explored.
  Authors: Medina Flintsch, Alejandra; Clarke, Robert Michael; Hughes, Ronald Granger; Trimble, Tammy E.; Scott, Jeremy
  Authors: Medina Flintsch, Alejandra; Clarke, Robert Michael; Hughes, Ronald Granger; Trimble, Tammy E.; Scott, Jeremy
  Year: 2013
  Document Type: Paper
  Subject: Motor Carriers; Safety and Human Factors
  Session: 673
  Paper Number: 13-3505
• Modeling Frequency of Truck Crashes on Limited-Access Highways
  Abstract: Freight can be efficiently transported between most locations in the country using large trucks. Number of trucks and vehicle miles traveled by trucks have both increased over the last several decades, thereby increasing the chances of more frequent truck crashes. Involvement of large trucks in crashes can cause much damage and serious injuries, due to their large sizes and heavy weights. The purpose of this study was to identify the relationships between large truck crashes and traffic and geometric characteristics on limited access highways. Crash and traffic- and geometric-related data for Kansas were utilized in this study. A Poisson regression model and a negative binomial regression model were developed for understanding the relationships between large truck crashes and traffic and geometric characteristics. Based on model-fitting statistics, the negative binomial model was found to be the better model and was used to identify the important characteristics. Significant variables in the negative binomial model were section length, number of lanes, horizontal curvature, vertical grade, Annual Average Daily Traffic (AADT) per lane, large truck percentage, and inside shoulder width. Highway design features such as horizontal curvature, vertical grade, and inside shoulder width are factors which can be implemented to prevent large truck crashes. By addressing identified factors, safety could be promoted through introduction of appropriate engineering improvements.
  Authors: Amarasingha, Niranga; Dissanayake, Sunanda
  Authors: Amarasingha, Niranga; Dissanayake, Sunanda
  Year: 2013
  Document Type: Paper
  Subject: Motor Carriers; Safety and Human Factors
  Session: 673
  Paper Number: 13-3970
• Influence of Managers on Fleet Vehicle Crashes: Application of Multilevel Models
  Abstract: Data from various sources indicates that in most developed countries approximately 25% of road collisions and 30% of occupational fatalities involve someone driving for work. This represents a significant cost to society, the economy, organisations and families. Such collisions are not confined to large commercial vehicles, but frequently involve smaller vehicles where driving is secondary to the employees’ main task. Driving for work is associated with increased risk of involvement in a fatal or serious road traffic collision. Increasingly fleet management has focused on safety and driver behaviour as well as asset management and cost control. Studies have shown that managing the behaviour of both drivers and the organisation as a whole can contribute to incremental improvements in safety.Understanding crash risk must include the background of random events that drivers encounter. This variation has been taken into account when studying interventions such as speed camera location and training schemes. In contrast, the impact of managers on driver outcomes has been less well investigated particularly when based on actual motor insurance claims data. For this reason, this paper reports on a study that rigorously incorporates the influence of managers within a driver claims model; not simply as a nuisance factor but rather as a topic of interest. It is based on employees’ insurance claims from a large UK company, which operates a fleet of approximately 37,000 vehicles and has made significant progress in applying a range of strategies to enhance driver safety over a 10 year period.The paper concludes that identifying managers lying outside the normal range, and associated manager characteristics, can lead to valuable interventions at higher levels of the organisation. This manager effect is found to be statistically significant indicating that the work has important implications for research, policy and practice to improve road safety performance in organisations where people are required to travel as part of their work.
  Authors: Darby, Phillip; Quddus, Mohammed A.; Raeside, Robert; Ison, Stephen; Murray, Will
  Authors: Darby, Phillip; Quddus, Mohammed A.; Raeside, Robert; Ison, Stephen; Murray, Will
  Year: 2013
  Document Type: Paper
  Subject: Motor Carriers; Safety and Human Factors
  Session: 673
  Paper Number: 13-3577
• Modeling Injury Outcomes of Crashes Involving Heavy Vehicleson Texas Highways
  Abstract: A growing concern related to large-truck crashes has increased in the State of Texas in recent years due to the potential economic impacts and level of injury severity that can be sustained. Yet, studies on large truck involved crashes highlighting the contributing factors leading to injury severity have not been conducted in detail in the State of Texas especially for its interstate system. In this study, we analyze the contributing factors related to injury severity by utilizing Texas crash data based on a discrete outcome based model which accounts for possible unobserved heterogeneity related to human, vehicle and road-environment. We estimate a random parameter logit model (i.e., mixed logit) to predict the likelihood of five standard injury severity scales commonly used in Crash Record and Information System (CRIS) in Texas – fatal, incapacitating, non-incapacitating, possible, and no injury (property damage only). Estimation findings indicate that the level of injury severity outcomes is highly influenced by a number of complex interactions between factors and the effects of the some factors can vary across observations. The contributing factors include drivers’ demographics, traffic flow condition, roadway geometrics, land use and temporal characteristics, weather, and lighting conditions.
  Authors: Islam, Mouyid Bin; Hernandez, Salvador
  Authors: Islam, Mouyid Bin; Hernandez, Salvador
  Year: 2013
  Document Type: Paper
  Subject: Motor Carriers; Safety and Human Factors
  Session: 673
  Paper Number: 13-5253
• Car-Truck Crashes in National Motor Vehicle Crash Causation Study
  Abstract: The National Motor Vehicle Crash Causation Survey (NMVCCS) provided in-depth investigative data on pre-crash factors and other characteristics of 5,470 crashes involving light passenger vehicles (“cars”). Within the dataset, 199 crashes, representing 79,721 crashes nationally, were collisions between cars and large trucks. Although only 3.6% of the NMVCCS, this data subset is a significant source of information about the genesis of car-truck crashes. This includes variables relating to crash configurations, critical reasons, associated factors, and conditions of occurrence. Findings supplement and generally corroborate those from the Large Truck Crash Causation Study. However, NMVCCS data are more recent and represent a wider range of crash severities. Cars were more likely than trucks to be the encroaching vehicle in car-truck collisions. Overall, 71.0% of assigned Critical Reasons (CRs) were to the car. Cars were more likely to be out-of-control prior to impact and to violate rights-of-way. Associated driver factors relating to impairment or aggressive acts were assigned more frequently to car drivers. Trucks were more likely to be assigned vehicle-related CRs and associated factors, however. Nationally, about 80% of truck-related fatalities occur in car-truck crashes, and car drivers contribute strongly to their genesis. Understanding their critical errors is essential for the development of effective countermeasures.
  Authors: Knipling, Ronald R.
  Authors: Knipling, Ronald R.
  Year: 2013
  Document Type: Paper
  Subject: Motor Carriers; Safety and Human Factors
  Session: 673
  Paper Number: 13-1548
  Practice-Ready: Yes
• Bus Accident Severity and Passenger Injury: Evidence from Denmark
  Abstract: Bus safety is a concern not only in developing countries, but also in the U.S. and Europe. In Denmark, disentangling risk factors that are positively or negatively related to bus accident severity and injury occurrence to bus passengers can contribute to promote safety as an essential principle of sustainable transit and advance the vision “every accident is one too many”. Bus accident data were retrieved from the national accident database for the period 2002-2011. A generalized ordered logit model allows analyzing bus accident severity and a logistic regression enables examining occurrence of injury to bus passengers.Bus accident severity is positively related to (i) the involvement of vulnerable road users, (ii) high speed limits, (iii) night hours, (iv) elderly drivers of the third party involved, and (v) bus drivers and other drivers crossing in yellow or red light. Occurrence of injury to bus passengers is positively related to (i) the involvement of heavy vehicles, (ii) crossing intersections in yellow or red light, (iii) open areas, (iv) high speed limits, and (v) slippery road surface. The findings of the current study provide a comprehensive picture of the bus safety situation in Denmark and suggest the necessity of further research into bus drivers’ attitudes and perceptions of risks and road users’ perceptions of bus operations. Moreover, these findings suggest the need for further training into bus drivers’ hazard recognition skills and infrastructural solutions to forgive possible driving errors.
  Authors: Prato, Carlo Giacomo; Kaplan, Sigal
  Authors: Prato, Carlo Giacomo; Kaplan, Sigal
  Year: 2013
  Document Type: Paper
  Subject: Motor Carriers; Safety and Human Factors
  Session: 673
  Paper Number: 13-1818
  Practice-Ready: Yes
• Roundabouts and Accommodation of Large Trucks: Motor Carrier Perspective
  Abstract: With nearly 200 new constructions every year, roundabouts are increasingly utilized as alternatives for signalized and stop-controlled intersections in the United States. Proponents often cite numerous safety improvements, including reductions of overall crash rates at converted intersections, as justification to increase the development of roundabouts. However, the growing use of roundabouts may be inhibiting the safe and efficient movement of large trucks due to roundabout design elements that conflict with truck operations. ATRI researchers, collaborating with Kansas State University, conducted an online survey of motor carriers to explore features that may possibly hinder roundabout use by large trucks. The survey collected industry observations regarding the challenges experienced by commercial truck drivers while negotiating roundabouts. This paper synthesizes those observations and documents the anecdotal experiences that will allow researchers and roadway designers to identify and categorize unknown roundabout design issues and possible solutions. This research can hopefully be used as the first conversation in a productive dialogue between transportation planners and the trucking industry on the issue of roundabout design for large truck usage.
  Authors: Park, Lisa K.; Pierce, David
  Authors: Park, Lisa K.; Pierce, David
  Year: 2013
  Document Type: Paper
  Subject: Motor Carriers; Safety and Human Factors
  Session: 673
  Paper Number: 13-3008
  Practice-Ready: Yes
• Stress During Driving for Novice Truck Drivers
  Authors: Gyawali, Sunil
  Authors: Gyawali, Sunil
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Motor Carriers; Safety and Human Factors
  Session: 673
  Paper Number: 13-1510
• Bus Accident Severity and Passenger Injury: Evidence from Denmark
  Authors: Prato, Carlo
  Authors: Prato, Carlo
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Motor Carriers; Safety and Human Factors
  Session: 673
  Paper Number: 13-1818
• Car-Truck Crashes in National Motor Vehicle Crash Causation Study
  Authors: Knipling, Ronald
  Authors: Knipling, Ronald
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Motor Carriers; Safety and Human Factors
  Session: 673
  Paper Number: 13-1548
• Crash Rates on Interstate Segments with Very Large Truck Percentages
  Authors: Young, Rhonda
  Authors: Young, Rhonda
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Motor Carriers; Safety and Human Factors
  Session: 673
  Paper Number: 13-0982
• Safety Analysis and Intervention Requirements for Contracting Commercial Vehicles and Drivers on Connecticut DOT Contracts
  Abstract:

  Connecticut is one of the first states in the country to enact policies and practices for qualifying contractors for using commercial vehicles on state contracts. The current contractor qualification process was stated as a verbal directive from the Govern of Connecticut’s’ office in response to a deadly commercial vehicle crash on Avon Mountain in 2005. The objectives of this study are to; 1) Identify how other states seek to assure the safety of vehicles utilized in state contracts; 2) Identify and summarize the purposes for which the FMCSA, CSA/SMS is intended; 3) Review Connecticut’s current contractor qualification system and the use of CSA/SMS for use in making contractor selection decisions; 4) Identify alternatives to utilizing CSA 2010/SMS, if appropriate, to accomplish state goals of commercial vehicle safety on state contracts. The study recommendations identify a suggested revised contractor qualification process that focuses on contractor accountability and state agency review of qualification requirements. Furthermore, the proposed qualification system requires that subcontractors engaged by a primary contractor be held to the same qualification requirement standards as primary contractors.

  Authors: Jackson, Eric; Strauss, Richard
  Authors: Jackson, Eric; Strauss, Richard
  Year: 2013
  Document Type: Paper
  Subject: Motor Carriers; Safety and Human Factors
  Session: 673
  Paper Number: 13-1356
  Practice-Ready: Yes