Countermeasures

SafeTREC director Julia Griswold presents to California Senate on how to address systemic risk in our transportation system

March 20, 2026
Submitted by Kris Leckie
Earlier this month, SafeTREC director Julia Griswold presented at a joint Senate informational hearing in Sacramento, convened by California State Senators Dave Cortese (D-San Jose) and Jesse Arreguín (D-Oakland), chairs of the Transportation Committee and Public Safety Committee respectively....

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
2005

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.

Pedestrian and Bicycle Safety Evaluation for the City of Emeryville at Four Intersections

Johnson, Emily S.
Ragland, David R.
Cooper, Jill F.
O'Connor, Terri
2005

The City of Emeryville is small in area (1.2 square miles) and population (7,000), but it is one of the most regionally connected cities in the Bay Area (California). Emeryville is situated at the eastern end of the San Francisco-Oakland Bay Bridge, contains the intersection of Interstate Highway 80 (I-80) with several regional and other interstate highways, and has extensive transportation access by Amtrak Rail, Alameda County (AC) Transit and heavy cargo facilities at the nearby Port of Oakland. The city has many large employers and several large shopping areas, and the daytime...

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

Bui, Huong
Arnold, Lindsay S.
Cooper, Jill F.
Ragland, David R.
2006

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.

Estimating Pedestrian Accident Exposure: Protocol Report

Greene-Roesel, Ryan
Diogenes, Mara Chagas
Ragland, David R.
2007

Walking is a healthful, environmentally benign form of travel, and is the most basic form of human mobility. Walking trips account for more than 8 percent of all trips taken in California, making walking the second most commonly used mode of travel after the personal automobile (Caltrans, 2002). In addition, many trips made by vehicle or public transit begin and end with walking.

In spite of the importance and benefits of walking, pedestrians suffer a disproportionate share of the harm of traffic incidents in California. As noted above...

What They Don’t Know Can Kill Them

Mitman, Meghan F.
Ragland, David R.
2007

Traffic safety researchers have long argued that driver behavior outweighs physical elements (such as road design) as a causal factor in motor vehicle collisions. A fundamental causal component of pedestrian-vehicle collisions is also behavior—that of the driver and that of the pedestrian. One determinant of this behavior may be whether the driver, the pedestrian, or both understand the motor vehicle code, which demarcates right-of-way in pedestrian-vehicle interactions. That is, inappropriate or unlawful behavior may occur because the law is not understood or is misunderstood. Previous...

Pedestrian Counting Methods at Intersections: a Comparative Study

Diogenes, Mara Chagas
Greene-Roesel, Ryan
Arnold, Lindsay S.
Ragland, David R.
2007

Resources for implementing countermeasures to reduce pedestrian collisions in urban centers are usually allocated on the basis of need, which is determined by risk studies. They commonly rely on pedestrian volumes at intersections. The methods used to estimate pedestrian volumes include direct counts and surveys, but few studies have addressed the accuracy of these methods. This paper investigates the accuracy of three common counting methods: manual counts using sheets, manual counts using clickers, and manual counts using video cameras. The counts took place in San Francisco. For the...

Rail Crossings: A Strategy to Select Countermeasure Improvements for Rail-Highway Crossings in California

Cooper, Douglas L.
Ragland, David R.
2007

Rail crossing crashes have declined in the past 30 years, both nationally and in California. This is largely attributed to the closing of a large number of crossings as well as the deployment of a wide range of countermeasures, including signal systems, gating and grade separation programs. However, the number of crashes and subsequent injuries and deaths is still unacceptably high. Rail crossings provide different levels of warnings from four-quadrant gates down to stop signs. To understand how the state of California can best utilize state and federal funding available through SAFETEA-LU...

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.
2007

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.

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

Ragland, David R.
Zabyshny, Aleksandr
2003

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...