AEP Biomechanics and Anthropometry 1 — Questions and Answers
Question 1: What is anthropometry primarily concerned with?
- The study of human body measurements and physical dimensions (Correct answer)
- The analysis of workplace chemical exposures
- The evaluation of cognitive workload in task design
- The measurement of environmental noise levels
Correct answer: The study of human body measurements and physical dimensions
Anthropometry is the scientific study of human body measurements and physical dimensions used to design products and environments that fit the human population.
Question 2: Which spinal segment is most commonly assessed when evaluating lumbar compression forces during manual material handling?
- C5-C6
- T12-L1
- L5-S1 (Correct answer)
- L1-L2
Correct answer: L5-S1
The L5-S1 disc is the most commonly analyzed segment because it experiences the greatest compressive and shear forces during lifting and bending tasks.
Question 3: Torque (moment of force) is calculated as the product of force and which other variable?
- Mass of the object
- Perpendicular distance from the pivot point (moment arm) (Correct answer)
- Velocity of movement
- Duration of force application
Correct answer: Perpendicular distance from the pivot point (moment arm)
Torque equals force multiplied by the perpendicular distance from the line of action to the pivot point, known as the moment arm.
Question 4: When designing a workstation to accommodate the broadest population, which anthropometric range is typically recommended as the design target?
- 5th to 95th percentile (Correct answer)
- 10th to 90th percentile
- 25th to 75th percentile
- 1st to 99th percentile
Correct answer: 5th to 95th percentile
Designing for the 5th to 95th percentile accommodates 90% of the target population while remaining practically achievable, which is the standard ergonomic design convention.
Question 5: What does 'static anthropometry' measure?
- Body dimensions taken with the body in fixed, standardized positions (Correct answer)
- Forces exerted during dynamic movement
- Postural changes across a full work shift
- Muscle activation patterns during lifting
Correct answer: Body dimensions taken with the body in fixed, standardized positions
Static anthropometry measures body dimensions such as stature, sitting height, and reach in standardized, fixed positions without movement.
Question 6: The NIOSH maximum permissible compressive force limit at the L5/S1 disc for lifting tasks is:
- 2,700 N
- 3,400 N (Correct answer)
- 4,500 N
- 6,400 N
Correct answer: 3,400 N
NIOSH sets 3,400 N (approximately 770 lbs) as the maximum permissible limit for L5/S1 disc compression, above which injury risk for most workers is considered unacceptable.
Question 7: Which biomechanical principle explains why holding a load close to the body significantly reduces spinal stress?
- Increased friction between load and body reduces shear forces
- Shorter moment arm decreases the torque required from back muscles (Correct answer)
- The load weight is transferred to the hips rather than the spine
- Proximity activates larger leg muscles to compensate
Correct answer: Shorter moment arm decreases the torque required from back muscles
Holding a load close to the body shortens the moment arm from the load to the spine, dramatically reducing the torque that back extensor muscles must generate and thus lowering spinal compression forces.
AEP Biomechanics and Anthropometry 1
What is anthropometry primarily concerned with?