CIEE Workstation Design & Optimization 3 — Questions and Answers
Question 1: Which reach zone concept is most critical when designing a workstation to prevent shoulder abduction and elevation?
- Maximum reach envelope
- Primary (normal) work zone (Correct answer)
- Secondary work zone
- Tertiary storage zone
Correct answer: Primary (normal) work zone
The primary (normal) work zone—defined by forearm rotation with the elbow at the side—keeps frequently used items within reach without shoulder loading.
Question 2: An industrial ergonomist is evaluating leg clearance at a seated workstation. The minimum recommended thigh clearance between the seat and the underside of the work surface is approximately:
- 10 cm (4 in)
- 16 cm (6.3 in) (Correct answer)
- 20 cm (7.9 in)
- 25 cm (9.8 in)
Correct answer: 16 cm (6.3 in)
ANSI/HFES 100-2007 recommends a minimum thigh clearance of approximately 16 cm to accommodate seated posture changes without contact.
Question 3: Which factor most directly contributes to contact stress (pressure points) at a workstation?
- Repetitive pinch grip on tools
- Hard, sharp workstation edges contacting soft tissue (Correct answer)
- Static neck flexion over 20°
- Extended reach beyond the secondary work zone
Correct answer: Hard, sharp workstation edges contacting soft tissue
Contact stress occurs when hard or sharp surfaces press against soft tissue, compressing nerves and blood vessels, and is addressed by padding or rounding edges.
Question 4: When designing a workstation for use by both male and female workers of varying stature, the design should prioritize which anthropometric approach?
- Design for the 50th-percentile worker
- Design for the 95th-percentile male
- Design for adjustability to accommodate the 5th–95th percentile range (Correct answer)
- Design for the 5th-percentile female
Correct answer: Design for adjustability to accommodate the 5th–95th percentile range
Adjustable workstations that span the 5th–95th percentile range are the accepted ergonomic standard for mixed-population use.
Question 5: A CIEE candidate is reviewing footrest requirements at a sedentary workstation. A footrest is indicated when:
- The worker weighs more than 200 lbs
- The worker's feet do not reach the floor after setting the chair to an ergonomic seat height (Correct answer)
- The floor is made of concrete
- The workstation includes a keyboard tray
Correct answer: The worker's feet do not reach the floor after setting the chair to an ergonomic seat height
A footrest is required when raising the chair to achieve proper elbow-to-work-surface alignment results in the worker's feet dangling without floor contact.
Question 6: Which of the following workstation modifications best reduces lumbar loading during prolonged seated computer work?
- Increasing seat pan tilt forward by 10°
- Adding lumbar support that maintains the natural lordotic curve (Correct answer)
- Raising the monitor 5 cm above current height
- Using a split keyboard to reduce ulnar deviation
Correct answer: Adding lumbar support that maintains the natural lordotic curve
Lumbar support that preserves the lumbar lordosis reduces disc pressure and paraspinal muscle activity compared to unsupported sitting.
Question 7: Glare on a computer monitor is classified as either direct or reflected. Which control is most effective against veiling reflections (reflected glare) on screen?
- Increasing ambient lighting intensity
- Repositioning the monitor so light sources are to the side rather than behind or in front of the worker (Correct answer)
- Applying a high-gloss screen protector
- Reducing monitor refresh rate
Correct answer: Repositioning the monitor so light sources are to the side rather than behind or in front of the worker
Veiling reflections are eliminated most effectively by repositioning the monitor perpendicular to windows and overhead lights so reflections do not fall on the line of sight.
CIEE Workstation Design & Optimization 3
Which reach zone concept is most critical when designing a workstation to prevent shoulder abduction and elevation?