NSC Ergonomics 2 — Questions and Answers
Question 1: Which type of hand tool design best reduces wrist deviation during repetitive tasks?
- Straight-handled tool
- Pistol-grip or bent-handle tool (Correct answer)
- Tools with smooth metal handles
- Lightweight plastic tools
Correct answer: Pistol-grip or bent-handle tool
Pistol-grip or bent-handle tools allow the wrist to remain in a neutral position, reducing ulnar or radial deviation stress.
Question 2: What is the primary ergonomic concern with prolonged use of a computer mouse?
- Increased eye strain
- Ulnar nerve compression and shoulder strain (Correct answer)
- Lower back compression
- Ankle dorsiflexion fatigue
Correct answer: Ulnar nerve compression and shoulder strain
Extended mouse use can compress the ulnar nerve at the wrist and cause shoulder strain from reaching away from the body.
Question 3: In the context of NSC ergonomics guidelines, what does 'neutral posture' refer to?
- A posture with no movement at all
- Body position where joints are not at extremes of their range of motion (Correct answer)
- Lying flat on the back
- Sitting with legs elevated
Correct answer: Body position where joints are not at extremes of their range of motion
Neutral posture means the body's joints are near the middle of their range of motion, minimizing stress on muscles and tendons.
Question 4: Which ergonomic principle applies when a worker adjusts their workstation to fit their body rather than adapting their body to the workstation?
- Force reduction
- Fitting the task to the worker (Correct answer)
- Administrative controls
- Engineering out the hazard
Correct answer: Fitting the task to the worker
Fitting the task to the worker is a core ergonomic principle that modifies equipment or processes to suit human capabilities.
Question 5: A warehouse worker lifts boxes from floor level repeatedly. Which change would MOST reduce lumbar spine loading?
- Wearing a back belt
- Raising the pallet to knee or mid-thigh height (Correct answer)
- Slowing down the pace of work
- Increasing grip strength training
Correct answer: Raising the pallet to knee or mid-thigh height
Raising the starting height of the load reduces the forward trunk lean that dramatically increases lumbar compressive forces.
Question 6: Which of the following best describes 'contact stress' in ergonomics?
- Stress caused by poor lighting conditions
- Pressure on soft tissue from a hard edge or object (Correct answer)
- Mental stress from workplace conflict
- Vibration from heavy machinery
Correct answer: Pressure on soft tissue from a hard edge or object
Contact stress occurs when a hard surface edge presses against soft tissue, restricting blood flow and compressing nerves.
Question 7: According to NIOSH ergonomic recommendations, what is the maximum recommended weight for a two-handed lift under ideal conditions?
- 25 lbs
- 35 lbs
- 51 lbs (Correct answer)
- 75 lbs
Correct answer: 51 lbs
The NIOSH Lifting Equation sets the recommended weight limit (RWL) with a maximum action limit of 51 lbs under ideal lifting conditions.
NSC Ergonomics 2
Which type of hand tool design best reduces wrist deviation during repetitive tasks?