ACTAR Visibility & Lighting Conditions 2

Question 1

High-beam headlights on a standard passenger vehicle typically illuminate the road to approximately:

Accepted Answer

350–450 feet

Answer

160 feet

Answer

250 feet

Answer

600 feet

Question 2

The term 'maintained illuminance' in road lighting, as defined by the Illuminating Engineering Society (IES), refers to:

Accepted Answer

The average illuminance sustained over the life of the luminaire accounting for light loss factors

Answer

The maximum illuminance measured immediately after lamp installation

Answer

The illuminance level required only at signalized intersections

Answer

The minimum federal illuminance mandated at all accident scenes

Question 3

In the context of visibility during accident reconstruction, 'threshold contrast' refers to:

Accepted Answer

The minimum luminance difference required for an observer to detect an object against its background

Answer

The difference in color between a vehicle and the road surface

Answer

The legal minimum brightness required for traffic signs under MUTCD

Answer

The contrast ratio between high-beam and low-beam headlight output

Question 4

What is the primary function of retroreflective sheeting on traffic signs in relation to nighttime accident reconstruction?

Accepted Answer

To return light from vehicle headlights back toward the driver, making the sign visible at night

Answer

To increase the sign's surface area for better text placement at distance

Answer

To absorb ambient light during the day and release it as glow in the dark

Answer

To reduce glare from streetlights reflecting onto the sign face

Question 5

A traffic accident reconstructionist analyzing nighttime visibility would use photometric data primarily to:

Accepted Answer

Determine how road lighting or headlights illuminate the scene and affect driver visibility

Answer

Calculate the coefficient of friction at the accident scene

Answer

Measure vehicle speed using event data recorder (EDR) outputs

Answer

Assess structural damage patterns on vehicles involved in the collision

Question 6

Which of the following best describes 'disability glare' versus 'discomfort glare'?

Accepted Answer

Disability glare reduces visual performance; discomfort glare causes annoyance without necessarily impairing vision

Answer

Disability glare is caused by oncoming lights only; discomfort glare is caused exclusively by sunlight

Answer

Disability glare is permanent impairment; discomfort glare is temporary

Answer

Disability glare occurs only at highway speeds; discomfort glare occurs at low speeds in parking lots

Question 7

When evaluating a nighttime accident scene, a reconstructionist measures the 'effective perception distance' as:

Accepted Answer

The distance at which a driver could first have detected and identified a specific hazard under the prevailing conditions

Answer

The distance from the stop bar to the first point of impact

Answer

The distance the vehicle traveled during the driver's reaction time alone

Answer

The total braking distance from maximum speed to complete stop