NSC Ergonomics 3 — Questions and Answers
Question 1: Which muscle group is MOST often affected by prolonged static loading during computer work?
- Quadriceps
- Trapezius and neck muscles (Correct answer)
- Biceps brachii
- Gastrocnemius
Correct answer: Trapezius and neck muscles
The trapezius and cervical muscles sustain prolonged low-level static contraction to hold the head and shoulders in position during desk work.
Question 2: What ergonomic risk factor is associated with using a vibrating tool for extended periods?
- Carpal tunnel syndrome only
- Hand-arm vibration syndrome (HAVS) (Correct answer)
- Plantar fasciitis
- Tennis elbow exclusively
Correct answer: Hand-arm vibration syndrome (HAVS)
Hand-arm vibration syndrome (HAVS) causes vascular and neurological damage in the hands and arms from prolonged exposure to vibrating tools.
Question 3: In ergonomic workstation design, what is the recommended distance between the eyes and a computer monitor?
- 10–15 inches
- 20–40 inches (Correct answer)
- 50–60 inches
- Over 60 inches
Correct answer: 20–40 inches
OSHA and NSC guidelines recommend placing the monitor approximately 20–40 inches from the eyes to reduce eyestrain and neck strain.
Question 4: Which ergonomic hazard category does 'whole-body vibration' (WBV) fall under?
- Chemical hazard
- Physical ergonomic hazard (Correct answer)
- Psychosocial hazard
- Biological hazard
Correct answer: Physical ergonomic hazard
Whole-body vibration is classified as a physical ergonomic hazard, commonly affecting forklift operators and truck drivers.
Question 5: A grocery cashier develops wrist pain after months of scanning products. Which control measure is MOST effective at reducing cumulative trauma?
- Providing wrist splints during work
- Redesigning the checkout station to reduce reach and wrist angles (Correct answer)
- Posting warning signs about repetitive motion
- Requiring workers to report pain immediately
Correct answer: Redesigning the checkout station to reduce reach and wrist angles
Engineering controls like workstation redesign address the root cause of awkward postures and are more effective than personal protective devices.
Question 6: What is the recommended keyboard tray position to maintain a neutral wrist posture while typing?
- Tilted upward (positive tilt) at 15 degrees
- Level or slightly tilted downward (negative tilt) (Correct answer)
- At chin height
- Below the knees
Correct answer: Level or slightly tilted downward (negative tilt)
A level or negative-tilt keyboard position allows the wrists to remain straight and reduces ulnar deviation and wrist extension.
Question 7: Which of the following best describes a 'push' vs. 'pull' comparison in cart ergonomics?
- Pulling a cart is always safer than pushing
- Pushing is generally safer because it uses larger muscle groups and provides better control (Correct answer)
- Both are equally hazardous with no difference
- Pulling is safer only on inclines
Correct answer: Pushing is generally safer because it uses larger muscle groups and provides better control
Pushing a cart is generally preferred because it allows use of larger back and leg muscles, provides better visibility, and reduces shoulder strain.
NSC Ergonomics 3
Which muscle group is MOST often affected by prolonged static loading during computer work?