CEA CEA Lighting & Environmental Factors

Question 1

What is the recommended illuminance level (in foot-candles) for general office work according to IESNA guidelines?

Accepted Answer

30–50 fc

Answer

IESNA recommends 30–50 foot-candles for general office tasks to reduce eye strain while maintaining adequate visibility.

Question 2

Which type of lighting is MOST likely to cause veiling reflections on computer screens?

Accepted Answer

Overhead fluorescent luminaires positioned directly above the screen

Answer

Overhead luminaires positioned directly above a monitor create specular reflections on the screen surface, reducing contrast and increasing visual fatigue.

Question 3

What is the primary ergonomic concern when the luminance ratio between a task and its immediate surround exceeds 3:1?

Accepted Answer

Visual fatigue from repeated pupil adaptation

Answer

High luminance ratios force the eye to repeatedly adapt between bright and dim areas, causing visual fatigue over a workday.

Question 4

Thermal discomfort in an office is MOST directly evaluated by which combination of environmental parameters?

Accepted Answer

Radiant temperature, air temperature, humidity, and air velocity

Answer

ASHRAE 55 uses operative temperature (combining air and radiant temperature), humidity, and air velocity to assess thermal comfort.

Question 5

According to OSHA and NIOSH guidance, what is the action level for occupational noise exposure over an 8-hour TWA?

Accepted Answer

85 dBA

Answer

NIOSH sets the recommended exposure limit at 85 dBA as an 8-hour TWA, triggering hearing conservation program requirements.

(CEA) Certified Ergonomics Associate Practice Test

(CEA) Certified Ergonomics Associate Practice Test

CEA CEA Lighting & Environmental Factors