How Much Pedestrian Harm Can We Attribute to Larger Vehicles in the Fleet?

This study will explore pedestrian injury outcomes in traffic collisions and the kinetic energy transfer from vehicles, contingent upon impact speed and weight. While research has shown that higher vehicle speed and size amplify the risk of fatal pedestrian injuries, limited attention has been given to the combined effect of vehicle design and speed on pedestrian fatalities. Although speculation links the increasing pedestrian fatalities in the United States to the growth of a vehicle fleet dominated by larger and heavier modes, particularly Sport Utility Vehicles (SUVs), this hypothesis diverges. The research team proposes that at higher speeds, the significance of vehicle size diminishes in causing lethal pedestrian accidents. This claim is supported by the kinetic energy transfer expression where speed is raised to the second power, thus overshadowing the role of vehicle weight. However, lower-speed pedestrian crashes might involve different dynamics, particularly in neighborhoods and parking lots. Collisions with SUVs could elevate the chances of fatality not only due to excessive size but also due to potential chest or abdomen impacts followed by running over, owing to their higher hoods and larger forward blind spots compared to sedans. Consequently, differentiating the thresholds for speed and vehicle size as determinants of pedestrian injury severity becomes difficult, with each scenario demanding distinct countermeasures. Additionally, with the introduction of safety technologies such as pedestrian detection and emergency braking and increasing the trend towards vehicle electrification and automation leading to greater vehicle weight, understanding the extent of change in pedestrian injury risk is imperative. By employing econometric models, this study will utilize pedestrian crash and Vehicle Identification Number (VIN) data from California and Tennessee to investigate relationships among vehicle attributes, such as weight, speed, hood height, and safety features. For a more comprehensive understanding of these relationships, the study would also explore simulation techniques to model pedestrian-vehicle interaction during crashes involving different vehicle types, including SUVs and passenger cars.


  • English


  • Status: Active
  • Funding: $97369
  • Contract Numbers:


  • Sponsor Organizations:

    Office of the Assistant Secretary for Research and Technology

    University Transportation Centers Program
    Department of Transportation
    Washington, DC  United States  20590
  • Managing Organizations:

    Center for Pedestrian and Bicyclist Safety

    University of New Mexico
    Albuquerque, NM  United States  87131
  • Project Managers:

    Melendrez, Carman

    Stearns, Amy

  • Performing Organizations:

    University of Tennessee, Knoxville

    Center for Transportation Research (CTR)
    Knoxville, TN  United States  37996
  • Principal Investigators:

    Cherry, Christopher

  • Start Date: 20230601
  • Expected Completion Date: 20240531
  • Actual Completion Date: 0
  • USDOT Program: University Transportation Centers Program

Subject/Index Terms

Filing Info

  • Accession Number: 01890196
  • Record Type: Research project
  • Source Agency: Center for Pedestrian and Bicyclist Safety
  • Contract Numbers: 69A3552348336
  • Files: UTC, RIP
  • Created Date: Aug 17 2023 4:58PM