AEP Biomechanics and Anthropometry 3

Question 1

The 'reach envelope' concept in workstation design refers to:

Accepted Answer

The three-dimensional zone within which a worker can reach comfortably without harmful postures

Answer

The envelope containing all OSHA compliance documentation at a workstation

Answer

The range of adjustability built into a chair or desk

Answer

The maximum weight that can be safely lifted from floor to shoulder height

Question 2

Maintaining a neutral spine posture during lifting is biomechanically advantageous primarily because it:

Accepted Answer

Distributes spinal loads more evenly and reduces localized stress concentrations

Answer

Eliminates all compressive forces on intervertebral discs

Answer

Allows maximum forward reach to reduce horizontal distance to the load

Answer

Increases lumbar lordosis to activate the hip flexors

Question 3

In the NIOSH Revised Lifting Equation (1994), the Asymmetry Multiplier (AM) accounts for:

Accepted Answer

The angular displacement of the load from the sagittal (midline) plane

Answer

The weight asymmetry between the lifter's left and right arms

Answer

The frequency difference between tasks performed on alternate sides

Answer

Uneven floor surfaces that cause postural asymmetry

Question 4

According to biomechanical principles, increasing the horizontal distance of a load from the lumbar spine by a factor of two will:

Accepted Answer

Double the moment (torque) that must be countered by back muscles

Answer

Double the compressive force on the lumbar spine

Answer

Halve the required muscle force

Answer

Have no significant effect if the load weight remains constant

Question 5

Functional anthropometric data is preferred over static data for workstation design because:

Accepted Answer

Functional data captures the actual body dimensions and clearances needed during task performance

Answer

Static data is generally unavailable for most populations

Answer

Functional data is always larger than static data, providing a safety margin

Answer

Static measurements are taken in non-standard postures that are difficult to reproduce

Question 6

The action limit (AL) in the original NIOSH Work Practices Guide (1981) was set at approximately what compressive force on L5/S1?

Accepted Answer

2,700 N

Answer

1,500 N

Answer

3,400 N

Answer

5,000 N

Question 7

Which anthropometric design strategy is most appropriate when a single fixed dimension must serve a diverse population and adjustability is not feasible?

Accepted Answer

Design for the extreme user that creates the greatest risk or demand

Answer

Design for the average (50th percentile)

Answer

Design for the 5th percentile female only

Answer

Design for the 95th percentile male only