Perception-reaction time (PRT)
Definition
The elapsed time from when a driver can first perceive a hazard to when the brakes begin to apply. Olson and Farber established a standard 1.5-second value for alert drivers; design standards commonly use 2.5 s.
Related terms
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- Critical speed yaw mark
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- Delta-V
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- Skid mark
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Explained in
- Accident Reconstruction PhysicsThe elapsed time from when a driver can first perceive a hazard to when the brakes begin to apply. Olson and Farber established a standard 1.5-second value for...