What is the SHRP 2 Safety Data?

The central goal of the SHRP 2 Safety research program was to address the role of driver performance and behavior in traffic safety. This included developing an understanding of how the driver interacts with and adapts to the vehicle, traffic environment, roadway characteristics, traffic control devices, and the environment. It also included assessing the changes in collision risk associated with each of these factors and interactions. This information will support the development of new and improved countermeasures with greater effectiveness.

The second Strategic Highway Research Program (SHRP 2) conducted a naturalistic driving study (NDS) that was unprecedented in size and scope. The study collected data from more than 3,500 volunteer passenger-vehicle drivers, ages 16 to 98, during a three-year period, with most drivers participating for one to two years.

The study was conducted at sites in six states: Florida, Indiana, New York, North Carolina, Pennsylvania, and Washington. The two predominantly rural sites, in Indiana and Pennsylvania, covered about 10 counties each; the other four urban or mixed sites covered one to three counties each. The total study area encompassed more than 21,000 square miles.

Data collected included vehicle speed, acceleration, and braking; vehicle controls, when available; lane position; forward radar; and video views forward, to the rear, and on the driver’s face and hands. The NDS data file contains approximately 35 million vehicle miles, 5.4 million trips, 2,705 near-crashes, 1,541 crashes, and more than 1 million hours of video.

The companion Roadway Information Database (RID) contains detailed roadway data collected on 12,538 centerline miles of highways in and around the study sites (including horizontal curvature information, grade, superelevation, lanes information, lighting, shoulder, MUTCD signs, intersections, rumble strips, median, guardrail/barrier). Approximately 200,000 highway miles of data from the highway inventories of the six study states, and additional data on crash histories, traffic and weather conditions, work zones, and ongoing safety campaigns in the study sites were also included in the RID. The NDS and RID data can be linked, so that driving behavior and outcomes can be associated with the roadway environment.

The resulting Safety Database, which exceeds 2 petabytes in size, provides a wealth of information to study the role of driver performance and behavior in traffic safety and the effects of the interaction between drivers and the roadway environment on the risk of crashes.