Perception Reaction Time Calculator
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This table includes various aspects of PRT, including definitions, components, average times, and factors affecting it.
| Aspect | Details |
|---|---|
| Definition | The time that elapses from the instant a driver recognizes a hazard to the instant they take appropriate action4 |
| Also known as | Reaction time4 |
| Components | 1. Detection 2. Identification 3. Decision 4. Response4 |
| Average PRT | 0.25 seconds (250 milliseconds)12 |
| Range of normal PRT | 0.2 – 0.9 seconds1 |
| Fastest possible PRT | 100-120 milliseconds2 |
| Visual processing time | As little as 13 milliseconds2 |
| Auditory vs. Visual | Auditory reaction time is generally faster than visual3 |
| Commonly cited PRT in accident reconstruction | 1.5 seconds (based on Olson’s research)4 |
| Recommended PRT for safe steering response | At least 3 seconds4 |
| PRT in complex situations | Can increase to 2, 3, or even 5 seconds4 |
| Factors affecting PRT | 1. Age 2. Gender 3. Fatigue 4. Alcohol and drug use 5. Distractions 6. Stimulus type and intensity 7. Complexity of response 8. State of attention 9. Practice and training 10. Environmental factors123 |
It’s important to note that PRT can vary significantly depending on the situation and individual factors. Investigators and researchers should consider the specific circumstances when applying PRT values to their analyses.