Relationship between Speed and Risk of Fatal Injury: Pedestrians and Car Occupants (Road Safety Web Publication No. 16)

  • Published: Department for Transport, 2010
  • Authors: D. Richards
  • Date Added: 15 Mar 2013
  • Last Update: 15 Mar 2013
  • Format: pdf


To investigate the relationship between speed and the risk of fatal injury, for both pedestrians and car occupants.


Calculation of pedestrian injury risk curves using logistic regression. The curves were calculated from 3 data sources: Ashton and Mackay data from the 1970s, German In-depth Accident Study data from 1999-2007, and OTS and police fatal file data from 2000-2009.

Key Findings:

  • Comparison of the pedestrian risk curves from the different datasets shows that the risk of pedestrian fatality is generally higher for the dataset from the 1970s, indicating that the probability of pedestrians being killed when hit by the front of a car has reduced over the last 30 years.

  • In all of the pedestrian datasets, the risk of fatality increases slowly until impact speeds of around 30 mph. Above this speed, risk increases rapidly – the increase is between 3.5 and 5.5 times from 30 mph to 40 mph.

  • Although the risk of pedestrians being killed at 30mph is relatively low, approximately half of pedestrian fatalities occur at this impact speed or below.


Pedestrian injury, risk curves, OTS data.


Robust analysis.