CEA Office Ergonomics & Computer Use 3 — Questions and Answers
Question 1: According to ergonomic guidelines, how far should a computer monitor typically be positioned from the user's eyes?
- 10–18 inches
- 18–24 inches
- 20–40 inches (Correct answer)
- 40–60 inches
Correct answer: 20–40 inches
A viewing distance of 20–40 inches (approximately arm's length) is recommended to reduce eye strain and accommodate comfortable focus.
Question 2: Which posture-related risk is most commonly associated with using a mouse positioned too far from the keyboard?
- Wrist flexion
- Shoulder abduction and elevated arm (Correct answer)
- Lumbar hyperextension
- Cervical flexion
Correct answer: Shoulder abduction and elevated arm
Reaching outward for a distant mouse causes shoulder abduction, raising the arm and loading shoulder muscles and the rotator cuff.
Question 3: What is the primary purpose of document holders placed adjacent to computer monitors?
- Increase available desk space
- Reduce neck rotation and accommodation changes between source and screen (Correct answer)
- Improve room lighting balance
- Support the worker's forearms
Correct answer: Reduce neck rotation and accommodation changes between source and screen
Document holders position reference materials at the same height and distance as the screen, minimizing repetitive neck movement and focal adjustments.
Question 4: A supervisor notices workers frequently craning their necks upward to view their monitors. The most likely root cause is:
- Monitors are too far from the users
- Monitor tops are positioned above the user's eye level (Correct answer)
- Screen brightness is set too low
- Chairs are set too high
Correct answer: Monitor tops are positioned above the user's eye level
When the top of the monitor is above eye level, users must extend the neck to view the screen, causing cervical strain.
Question 5: Which type of chair adjustment has the greatest impact on reducing low-back compressive forces during computer work?
- Armrest height
- Seat pan depth
- Backrest recline angle (Correct answer)
- Seat height
Correct answer: Backrest recline angle
Reclining the backrest to approximately 100–110° reduces lumbar disc pressure compared to an upright 90° posture.
Question 6: An ergonomist identifies that a call-center worker holds the telephone between ear and shoulder while typing. The recommended solution is:
- Limit telephone use to 15 minutes per hour
- Provide a headset or speakerphone to free both hands (Correct answer)
- Raise the monitor to distract from discomfort
- Install a keyboard tray to lower hand position
Correct answer: Provide a headset or speakerphone to free both hands
A headset eliminates the need to cradle the phone, preventing lateral neck flexion and trapezius muscle overload.
Question 7: The concept of 'neutral posture' in computer ergonomics primarily aims to:
- Maximize the number of keystrokes per minute
- Maintain joints near their mid-range positions to reduce tissue stress (Correct answer)
- Ensure the worker faces directly toward windows
- Prevent the worker from changing position
Correct answer: Maintain joints near their mid-range positions to reduce tissue stress
Neutral posture keeps joints near their mid-range, where muscles and tendons operate most efficiently and with the least biomechanical stress.
CEA Office Ergonomics & Computer Use 3
According to ergonomic guidelines, how far should a computer monitor typically be positioned from the user's eyes?