Crash Data Analyses for Vehicle-To-Infrastructure Communications for Safety Applications

Chapter 7. Other Application Areas

Currently, there are two identified V2I for safety applications in the other application area category: secondary accident warning and lane departure warning. This section only describes the lane departure warning application. The secondary accident warning application could not be analyzed with NASS GES data because it is only a sample of crashes and not a comprehensive set in the database.

7.1 Lane Departure Crashes

The lane departure crashes application area is intended to warn drivers that they are about to unintentionally leave their lane or that they have unintentionally left their lane.

7.1.1 Associated Pre-Crash Scenarios

The application area targets single-vehicle and multi-vehicle pre-crash scenarios involving lane departure. It targets the same pre-crash scenarios as the speed curve warning application area; however, it is not limited to curve locations or speed-related crashes.

7.1.2 Magnitude of Problem

Based on weighted NASS GES data, there were an estimated 1,236,647 annual national target crashes, including more than 1 million single-vehicle crashes. The estimated cost of these crashes was more than $145 billion. Additionally, 35 percent of all the lane departure crashes resulted in fatalities or injuries.

7.1.3 Relevant Distributions

The majority of target crashes (92 percent) occurred on segments (62 percent occurred on tangent segments, and 30 percent occurred on curve segments). This is notable because lane departure crashes are not limited to curve locations.

While the majority of lane departure crashes occurred in urban areas (57 percent), more than 500,000 lane departure crashes occurred in rural areas, comprising the remaining 43 percent. Speed was a factor in more urban area crashes (18 percent) in comparison to rural areas (14 percent).

In total, 64 percent of all target crashes occurred on two-lane roads. Single vehicles had a slightly higher crash frequency (65 percent) than multi-vehicle crashes (59 percent).