BAA Speed-Safety Relationships

Project Description The overall study objective is to develop speed-safety relationships that can be used in the Highway Safety Manual and in other safety management tools such as Safety Analyst and usRAP models. The relationships will have functional forms consistent with previous research on speed effects and will have coefficient values derived from U.S. data. The speed-safety relationships will be developed with a combination of vehicle speed, roadway characteristics, and crash data for various roadway types using data from the six NDS study sites. Data Request Scope In Phase I of this project, 20 roadway segments of interest were identified based on data from the RID and trip density maps. The segments are 1- to 2-mi continuous segments that incorporate more than one adjacent linkID. This data set contains the data specified below for approximately 300 trips across the 20 identified segments. For Phase II of this project, an additional 100 roadway segments were identified, and approximately 500 traversals for each segment were provided. Data Specification This data set contains the following information for each individual trip that passed through each roadway segment of interest: TRIP: Trip number Vehicle ID Driver ID Vehicle type Driver age and gender Year, Month, and Day of Week Time of day TIME SERIES: Vehicle speed (mph) Vehicle location (latitude and longitude) Forward-radar data Continuous clock time