ACTAR Human Factors 2 — Questions and Answers
Question 1: What is the typical simple reaction time for an alert, unimpaired driver responding to a single expected stimulus?
- 0.1 seconds
- 0.75 seconds (Correct answer)
- 1.5 seconds
- 2.5 seconds
Correct answer: 0.75 seconds
Simple reaction time for an alert driver responding to a single expected stimulus is approximately 0.75 seconds (range ~0.5–1.0 s).
Question 2: In the PIEV model of driver response, what does the letter 'E' represent?
- Estimation of speed
- Emotion response
- Emotion-based avoidance
- Emotion is not part of PIEV (Correct answer)
Correct answer: Emotion is not part of PIEV
PIEV stands for Perception, Intellection, Emotion (sometimes omitted), and Volition—some formulations drop Emotion, making it PIV or use PRT instead.
Question 3: Which factor most significantly degrades a driver's hazard perception capability?
- Wearing sunglasses at dusk
- Blood alcohol concentration above 0.08% (Correct answer)
- Using cruise control on a highway
- Listening to the radio at moderate volume
Correct answer: Blood alcohol concentration above 0.08%
BAC above 0.08% substantially impairs hazard detection, tracking, and divided attention, making it the most significant degrader.
Question 4: A driver traveling at 60 mph with a perception-reaction time of 1.5 seconds will travel approximately how far before braking begins?
- 66 feet
- 100 feet
- 132 feet (Correct answer)
- 176 feet
Correct answer: 132 feet
60 mph = 88 ft/s; 88 × 1.5 = 132 feet of PRT distance before braking commences.
Question 5: What phenomenon occurs when a driver fixates visually on a hazard and steers toward it instead of away?
- Inattentional blindness
- Target fixation (moth effect) (Correct answer)
- Change blindness
- Saccadic suppression
Correct answer: Target fixation (moth effect)
Target fixation, sometimes called the moth effect, occurs when a driver steers toward an object they are fixating on rather than executing an avoidance path.
Question 6: Which of the following best describes 'inattentional blindness' in the context of traffic accident reconstruction?
- Failure to see due to poor lighting conditions
- Failure to perceive a visible object when attention is directed elsewhere (Correct answer)
- Temporary vision loss caused by glare
- Blindness caused by a medical condition during driving
Correct answer: Failure to perceive a visible object when attention is directed elsewhere
Inattentional blindness is the failure to notice a fully visible stimulus when attention is engaged by another task.
Question 7: How does workload-induced tunnel vision affect a driver's ability to detect peripheral hazards?
- It expands the useful field of view
- It has no measurable effect on peripheral detection
- It narrows the useful field of view, reducing peripheral hazard detection (Correct answer)
- It shifts fixation toward the periphery
Correct answer: It narrows the useful field of view, reducing peripheral hazard detection
Under high cognitive workload or stress, the useful field of view (UFOV) contracts, reducing a driver's ability to detect hazards outside the central visual zone.
ACTAR Human Factors 2
What is the typical simple reaction time for an alert, unimpaired driver responding to a single expected stimulus?