Mobility and transport
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How to recognize a fatigue-related crash?

The opinions expressed in the studies are those of the consultant and do not necessarily represent the position of the Commission.

How to recognize a fatigue-related crash?

Unlike the situation with alcohol-related crashes, no blood, breath, or other measurable test is currently available to quantify levels of sleepiness at a crash site. Thus current understanding of typical crash related characteristics come largely from inferential evidence.

In the United Kingdom, fatigue related crashes have been identified using the following criteria:

  • The vehicle has run off the road and/or collided with another vehicle or object
  • There is an absence of skid marks or braking
  • The driver could see the point of run-off or the object hit prior to the crash
  • Other causes are eliminated e.g. mechanical defect, speeding, excess alcohol, bad weather; and
  • Witnesses may report lane drifting prior to the crash [49][50]

Similarly in the United States, the Expert Panel on Driver Fatigue and Sleepiness [79] characterises a fatigue-related crash as follows:

  • The problem occurs during late night/ early morning or mid-afternoon
  • The crash is likely to be serious
  • A single vehicle leaves the roadway
  • The crash occurs on a high-speed road
  • The driver does not attempt to avoid a crash
  • The driver is alone in the vehicle