Ergonomic Tool & Equipment Selection Flashcards

A machinist must use a torque wrench repeatedly in a confined space. Which handle feature MOST prevents awkward wrist postures?

Answer: A T-handle or ratcheting head that allows force application without full wrist rotation

T-handles and ratcheting heads allow the worker to apply torque without repeatedly rotating the wrist to extremes, preventing awkward postures in tight spaces.

Which keyboard design feature MOST benefits users who are susceptible to wrist extension injuries?

Answer: Negative tilt (front edge higher than back edge) to keep wrists flat or slightly extended downward

Negative tilt positions the keyboard so wrists remain flat or in slight flexion rather than extension, reducing carpal tunnel pressure during typing.

When selecting cut-resistant gloves for a food processing line where repetitive cuts are required, which factor is the PRIMARY ergonomic trade-off?

Answer: Cut resistance rating vs. dexterity and grip sensitivity

Higher cut-resistance materials (e.g., thick HPPE or chain mail) reduce tactile feedback and dexterity, increasing grip force compensation — the key ergonomic trade-off.

A retail worker scans items at a checkout station for 8 hours. Which scanner type MOST reduces cumulative wrist stress compared to a standard pistol-grip handheld?

Answer: Presentation scanner (hands-free bioptic tunnel scanner)

A presentation or hands-free bioptic scanner eliminates repeated pick-up, grip, scan, and set-down motions, removing the primary source of cumulative wrist stress.

For selecting an ergonomic chair for a user with documented low-back pain, which single feature carries the MOST clinical evidence of benefit?

Answer: Adjustable lumbar support positioned at L3–L4

Adjustable lumbar support that targets the L3–L4 region maintains lumbar lordosis and is the chair feature with the strongest evidence base for reducing low-back pain.

A packaging operation requires workers to use box cutters for 5 hours per shift. Which safety-ergonomic knife design feature BEST addresses both injury risk and musculoskeletal strain?

Answer: Auto-retracting blade with a contoured handle sized for a power grip

An auto-retracting blade reduces laceration risk, while a contoured handle sized for a power grip reduces the grip force needed compared to thin, straight-handled cutters.

Which ergonomic principle guides the recommendation to use powered rather than manual torque tools when the required torque exceeds 1 Nm for repetitive tasks?

Answer: Substitution of a hazardous manual task with a less hazardous powered alternative

Using powered tools in place of manual ones for high-torque tasks applies the substitution principle — replacing a high-risk manual method with a lower-risk powered alternative.