CEA CEA Lighting & Environmental Factors 2 — Questions and Answers
Question 1: Which environmental factor is MOST directly associated with Sick Building Syndrome (SBS) complaints?
- Excessive natural light
- Poor indoor air quality and inadequate ventilation (Correct answer)
- High ambient noise above 85 dBA
- Very low relative humidity below 20%
Correct answer: Poor indoor air quality and inadequate ventilation
SBS is primarily linked to poor ventilation, volatile organic compounds, and biological contaminants in indoor air.
Question 2: The ASHRAE 55 standard defines a comfort zone primarily based on which two variables?
- Air speed and CO₂ level
- Operative temperature and relative humidity (Correct answer)
- Lighting and noise
- Metabolic rate and clothing insulation only
Correct answer: Operative temperature and relative humidity
ASHRAE 55 defines comfort envelopes using operative temperature on one axis and relative humidity on the other.
Question 3: What CLO value approximately represents typical business casual clothing worn in a US office?
- 0.2 clo
- 0.5 clo
- 1.0 clo (Correct answer)
- 1.5 clo
Correct answer: 1.0 clo
Typical business casual office attire (trousers, long-sleeve shirt, light jacket) approximates 1.0 clo of thermal insulation.
Question 4: Excessive vibration transmitted to the hand-arm system is MOST associated with which condition?
- Carpal Tunnel Syndrome
- Raynaud's phenomenon / Hand-Arm Vibration Syndrome (HAVS) (Correct answer)
- Lateral Epicondylitis
- Thoracic Outlet Syndrome
Correct answer: Raynaud's phenomenon / Hand-Arm Vibration Syndrome (HAVS)
Prolonged exposure to hand-transmitted vibration damages blood vessels and nerves, causing HAVS/Raynaud's phenomenon.
Question 5: ISO 2631 provides guidance for evaluating human exposure to which physical stressor?
- Thermal radiation
- Whole-body vibration (Correct answer)
- Electromagnetic fields
- Ultraviolet light
Correct answer: Whole-body vibration
ISO 2631 specifies methods for evaluating whole-body vibration and its potential health, comfort, and motion-sickness effects.
Question 6: Which approach BEST controls glare from a window in an office workstation?
- Increase overhead lighting intensity to match window brightness
- Position the monitor perpendicular to the window and use adjustable blinds (Correct answer)
- Move the monitor directly in front of the window
- Lower the monitor below the window sill
Correct answer: Position the monitor perpendicular to the window and use adjustable blinds
Placing the monitor perpendicular (at 90°) to the window and controlling window luminance with blinds minimizes both direct and reflected glare.
CEA CEA Lighting & Environmental Factors 2
Which environmental factor is MOST directly associated with Sick Building Syndrome (SBS) complaints?