Killing Speed

In 2001, speeding was a contributing factor in 30% of all fatal crashes, and nationally, 12,850 lives were lost in speed-related crashes. The economic cost of speeding to U.S. society is almost $40.4 billion per year. The severity of injury to pedestrians increases dramatically as speed rises. At 20 mph there is a 5% probability of death or serious injury. At 40 mph the probability has increased to 80%. Speed limits that are too high and speed compliance that is too low are both critical symptoms of unhealthy streets.

Relationship of Vehicle Speed to Probability of Death or Serious Injury
to a Struck Pedestrian

See also Social Marketing