Safety

Safety Performance of Experimental Pavement Types in California Using Before-and-After Comparisons

Oh, Soonmi
Ragland, David R.
Chan, Ching-Yao
2010

This study focused on safety performance of new pavement surface types. Open graded or coarse-textured roadway surfaces are advisable for high-speed, wet-weather traffic conditions. They provide drainage relief at the tire-pavement interface, reduce the steepness of the speed gradient, decrease the likelihood of hydroplaning, minimize splash and spray, reduce the glare from wet pavements, and improve high-speed skid resistance. Before-and-after comparisons using historical collision data from California Traffic Accident Surveillance and Analysis System (TASAS) were conducted to assess the...

San Pablo Avenue Pedestrian Signal Timing Optimization

Nguyen, Ahn
Ragland, David R.
2007

The focus of this study is to quantify the sufficiency of “Flashing Don’t Walk” (FDW) intervals at signalized pedestrian crossings in the San Pablo Avenue (SPA) corridor in Northern California. Our goal is to determine if pedestrian signal intervals on the SPA corridor can be optimized in a way that makes the pedestrian crossing environment safer and more comfortable for all pedestrians without diminishing vehicular throughput. This study provides a corridor-wide as well as a city-by-city assessment of FDW intervals on the SPA corridor. We suggest a possible tool to assist traffic control...

Pedestrian and Bicycle Safety Strategies for UC Berkeley Campus and Periphery: Recommendations for Implementation

Schneider, Robert J.
Grembek, Offer
Braughton, Mathew
Orrick, Phyllis
Ragland, David R.
2013

The high level of pedestrian, bicycle, and transit activity on city-owned streets surrounding the UC Berkeley campus creates a dynamic social environment and gives Berkeley much of its charm. But the streets around the campus (henceforth called the campus periphery) are also places where pedestrians and bicyclists have been injured or killed in collisions with automobiles. This creates liability for drivers, the City, and the University—and worse, causes suffering for crash victims and their families. Everyone has an interest in reducing the frequency and severity of pedestrian and bicycle...

Evaluation of the Accuracy of Global Positioning System Coordinates for Collision Locations in California

Bingham, John
Strang, Garrett
Oum, Sang Hyouk
2014

Traffic collision reports typically provide descriptive locations indicating where a collision occurred and referencing the nearest intersection. Global Positioning System (GPS) technology can be used to provide latitude and longitude coordinates in addition to the descriptive location and many states now include GPS coordinates in collision reports. However, research has shown that there is potential for numerous errors when police agencies use GPS to complete traffic collision reports. In California, GPS coordinates have been included in the statewide collision database since 2006, but...

Health Impacts of the School Commute

Lee, Murray
Orenstein, Marla
Richardson, Maxwell
Ragland, David R.
2008

A dramatic decline in walking and cycling to school has been observed in many geographic and cultural regions, and most children in the US are now driven to school in private vehicles. There are a number of health implications associated with the choice of commute mode, including traffic safety, exposure to air pollution, and levels of physical activity and obesity, and the risks and benefits of each must be weighed. This paper reviews current evidence on these risks and benefits for each health topic area. From a traffic safety perspective, buses are best, while the risks of private...

Applying Safety Treatments To Rail-Highway At-Grade Crossings

Cooper, Douglas L.
Ragland, David R.
2012

At-grade rail crossings provide different levels of warnings and/or barriers to alert drivers to the potential dangers presented by approaching trains. For some drivers, an activated warning system, rather than being a signal to stop, merely serves as a cue for the need to make a decision whether or not to cross. In California, for the ten-year period from 2001 to 2010, the result was 1,033 trainvehicle crashes resulting in 157 deaths and 458 injuries. The best solution to rail crossing crashes is to remove the need for the driver to engage in a potentially faulty decision-making process...

Vehicle Occupancy and Crash Risk

Geyer, Judy A.
Ragland, David R.
2004

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...

The Continuous Risk Profile Approach for the Identification of High Collision Concentration Locations on Congested Highways

Chung, Koohong
Ragland, David R.
Madanat, Samer
Oh, Soon Mi
2009

This paper documents a new method for monitoring traffic collision data from continuous roadway facilities to detect high collision concentration locations. Many existing methods for detecting collision concentration locations require segmentation of roadways and assume traffic collision data are spatially uncorrelated, resulting in both false positives (i.e., identifying sites for safety improvements that should not have been selected) and false negatives (i.e., not identifying sites that should have been selected). The proposed method does not require segmentation of roadways; spatial...

Giving cycling the green light: An overview of transportation in Ireland and the design of the National Cycle Network

Manton, Richard
2013

Similarly to the US, driving a car to work continues to gain ground in Ireland and the country is presented with major challenges in environment and health as a consequence. In safety, at least, Ireland has had some major successes. In 40 years, the number of fatalities has fallen from 640 to 162, a drop of 75%. Such improvements in road safety have been attributed to a combination of education, enforcement and engineering. Pedestrian and cyclist fatalities have each fallen by 66% in 20 years, however, this could be attributed to the lower numbers of people walking and cycling....