Daniel Convissor's Website

Relationship Between Motor Vehicle Speeds and Pedestrian Injuries

Graph created by Cora Roelofs of Komanoff Energy Associates, published in the Auto-Free Press, Transportation Alternatives, March/April 1993. Graph created from data found in Dieter Seinfried, Gute Argumente: Verker; Munich, CH Beck 1991.

Text Interpretation of Above Graph
Speed (mph)   
Minor Injury   
Major Injury   
Death
    3   
          55%   
          5% 
         0%
    6   
         100%   
         10% 
         0%
    9   
         100%   
         20% 
         0%
   20   
         100%   
         45% 
        15%
   25   
         100%   
         60% 
        25%
   30   
         100%   
         70% 
        40%
   35   
         100%   
         90% 
        50%
   40   
         100%   
        100% 
        70%
   45   
         100%   
        100% 
        95%
   50   
         100%   
        100% 
       100%

Effect of Speed Reductions (based on data above)
Speed Reduction 
    Reduction 
   Minor 
   Major 
 
to x from y (MPH) 
   in Speed 
  Injury 
  Injury 
  Death
25 from 35 
             (29%) 
      0%
    (33%) 
  (50%)
30 from 40 
             (25%) 
      0%
    (30%) 
  (43%)
35 from 45 
             (22%) 
      0%
    (10%) 
  (47%)
 
25 from 30 
             (17%) 
      0%
    (14%) 
  (38%)
30 from 35 
             (14%) 
      0%
    (22%) 
  (20%)
35 from 40 
             (13%) 
      0%
    (10%) 
  (29%)
 
25 from 40 
             (38%) 
      0%
    (40%) 
  (64%)

You might be interested in obtaining a copy of the report: Vehicle Travel Speeds and the Incidence of Fatal Pedestrian Collisions from the (Australian) Federal Office of Road Safety, GPO Box 594; Canberra, ACT 2601, Australia.

From the exec. summary: "A reduction of 5 km/hr in vehicle travelling speeds in the Adelaide area could be expected to result in a reduction of 30 percent of the incidence of fatal pedestrian collisions."

They also quoted another study (Proctor) that found chance of a fatality as follows:

Chance of Fatality
speed
   %
20 
     5
30 
    37
45 
    83

They also discuss the benefits of lower speeds in terms of stopping distance and reaction time distance.

From: D.Robinson
Newsgroups: rec.bicycles.misc
Subject: Stats on head injuries and cycle activity following mandatory helmets 
Date: 15 Jan 94 08:25:15 GMT