Motorized Vehicle Safety

Objective Stress Factors, Accidents, and Absenteeism in Transit Operators: A Theoretical Framework and Empirical Evidence

Greiner, Birgit A.
Krause, Niklas
Ragland, David R.
Fisher, June

The authors used observational job analysis as a conceptually based technique to measure stress factors unbiased by worker appraisal with 81 transit driving tasks on 27 transit lines. Stressor dimensions included work barriers that interfere with task performance due to poor technical-organizational design, time pressure, time binding (autonomy over time management), and monotonous conditions. Line-specific average stressor values were assigned to 308 transit operators who mainly worked the particular line. Logistic regression analyses showed associations for high work barriers and...

Automated Assessment of Safety-Critical Dynamics in Multi-modal Transportation Systems

Medury, Aditya
Yu, Mengqiao
Bourdais, Cedric
Grembek, Offer

Recent mobility trends reveal that travel is becoming increasing multi-modal in nature. Given the increase in the emphasis on multi-modal mobility there is a need to efficiently account for the multi-modal safety challenges it introduces. In light of this, it is of immense concern that the corresponding improvements made to traffic safety have not been commensurate across all modes. In this regard, one of the major challenges associated with efficiently designing and planning for a safe multi-modal environment is a limited understanding of multi-modal traffic behavior as explained by...

Do All Roadway Users Want the Same Things?

Sanders, Rebecca L.
Cooper, Jill F.

This paper presents findings from a recent study on roadway design preferences among pedestrians, drivers, bicyclists, and public transit users along a major urban corridor in the East San Francisco Bay Area. Sponsored by the California DOT, the research focused on exploring design preferences that could increase perceived traffic safety, walkability, bikability, and economic vitality along urban arterials. Results from an intercept survey showed that all user groups desire similar roadway design features along the test corridor, which carries 25,000-30,000 motorists bi-directionally...

Teens and Driving in California: Summary of Research and Best Practices

Bui, Huong
Arnold, Lindsay S.
Cooper, Jill F.
Ragland, David R.

The purpose of this guide is to present the major risk factors associated with teen driving in California and to highlight policy and program strategies that may be influential in reducing risk.

Driver Behavior at Rail Crossings: Cost-Effective Improvements to Increase Driver Safety at Public At-Grade Rail-Highway Crossings in California

Cooper, Douglas L.
Ragland, David R.

This report examines conditions affecting vehicle-train collisions at rail crossings in California, and recommends effective countermeasures and implementation strategies. In doing so, the report helps meet California’s goal of efficiently utilizing state and federal funding available through SAFETEA-LU for increasing the safety at public atgrade rail-highway crossings.

California Intersection Decision Support: A Systems Approach to Achieve Nationally Interoperable Solutions

Chan, Ching-Yao
Cody, Delphine
Cohn, Theodore
Dickey, Susan
Greenhouse, Dan
Mak, Tony
Marco, David
Nguyen, Khoi
Misener, James A.
Nowakowski, Christopher
Ossenbrugen, Paul
Ragland, David R.
Shladover, Steven E.
Tan, Swe-kuang
Vanderwerf, Joel
Wang, Xiqin
Zabyshny, Aleksandr
Zennaro, Marco

The overall IDS research plan was constructed to realize, in slightly more than three years, the requirements, tradeoffs assessment, and technology investigations necessary to define an IDS. Toward the end of the project we will combine our understanding of the problem definition, IDS technologies and our integration experience with a standard Caltrans intersection (with advanced controller) and design a deployable IDS demonstration that can be field tested.

Vehicle Occupancy and Crash Risk

Geyer, Judy A.
Ragland, David R.

This study explores the association between vehicle occupancy and a driver’s risk of causing a fatal crash, not wearing a seatbelt, and using alcohol. The survey population is the set of drivers represented in the Fatal Analysis Reporting System (FARS) (years 1992 to 2002). The independent variables are driver age, driver gender, passenger age, passenger gender, and vehicle occupancy. The outcome variables are whether the driver was at fault in causing the fatal crash, whether the driver wore a seatbelt, and whether the driver had been using alcohol. For male teenager drivers, driving with...

Impact of Pedestrian Presence on Movement of Left-Turning Vehicles: Method, Preliminary Results & Possible Use in Intersection Decision Support

Banerjee, Ipsita
Shladover, Steven E.
Misener, James A.
Chan, Ching-Yao
Ragland, David R.

Warning systems are being developed for left-turning vehicles at intersections where protected left-turns are not warranted or cannot be provided, based on limitations of right of way or intersection capacity. These are meant to provide warnings to left-turning vehicles of vehicles approaching from the opposite direction, when the time to turn may be deemed unsafe. To implement these warning systems, it is necessary to estimate in near real time, the probability of conflict between the two approaching vehicles. A study is being conducted with the help of video and radar at various...

Rural Road Links: A Review on Current Research Projects & Initiatives Aimed at Reducing Vehicle Crash Fatalities on Rural Roads

Quiros, Lesliam
Shaver, Barrett

Rural America accounts for a smaller and more dispersed portion of the nation’s population, yet it comprises a considerable portion of the transportation system. Rural areas account for approximately 83 percent of the land in the U.S and their roads account for 80 percent of the total U.S. road mileage and 40 percent of the vehicle miles traveled. Fatalities on rural roads surpass those in urban areas, even though urban areas are more densely populated and consequently, have a higher traffic flow. In 2001 alone, fatal crashes on rural areas accounted for 61 percent of all traffic...

Intersection Decision Support Project: Taxonomy of Crossing-Path Crashes at Intersections Using GES 2000 Data

Ragland, David R.
Zabyshny, Aleksandr

The Intersection Decision Support (IDS) Project is designed to reduce crossing-path (CP) crashes at intersections by providing crucial information to drivers that would help them avoid such crashes. Over the past decade, researchers have used the General Estimates System (GES, a representative sample of police-reported crashes in the US) and other data sources to develop a taxonomy of CP crashes and pre-crash scenarios as groundwork for crash-prevention efforts. The current study builds on and extends prior work by constructing a taxonomy of CP crashes using data from the 2000 GES and...