DOT Certification Practice Exam

According to FMCSA regulations, what must the medical examiner evaluate regarding a driver's eyes?

1. Iris symmetry

2. Pupil reactivity

3. Corneal thickness

4. Conjunctiva injection

The correct answer is: Pupil reactivity

The requirement for medical examiners to evaluate a driver's eyes according to FMCSA regulations is primarily focused on pupil reactivity. This evaluation is crucial because it provides insight into the nervous system's function and indicates how well the driver can respond to changes in light and visual stimuli, which are vital for safe driving. The ability to react properly to various lighting conditions is essential for activities such as adjusting to bright headlights at night or responding to sudden changes in road conditions. While aspects like iris symmetry, corneal thickness, and conjunctiva injection are relevant to overall eye health, they are not specifically mandated by FMCSA regulations as part of the medical examination for commercial drivers. Evaluating pupil reactivity directly correlates with the driver's visual capability, helping to ensure that they can safely operate a commercial vehicle on the road.