CES Manual Material Handling & Industrial Ergonomics

Question 1

In the NIOSH Revised Lifting Equation (1994), what is the Recommended Weight Limit (RWL) used to calculate?

Accepted Answer

A weight limit specific to the task conditions that protects most healthy workers

Answer

The RWL is the task-specific maximum load weight that protects approximately 75% of male and 99% of female workers from excessive spinal compression.

Question 2

The Lifting Index (LI) is calculated as:

Accepted Answer

Actual load weight divided by RWL

Answer

LI = Load Weight / RWL; an LI greater than 1.0 indicates increasing risk and a value above 3.0 represents high risk requiring immediate intervention.

Question 3

Which factor in the NIOSH Lifting Equation penalizes lifts that involve significant twisting of the torso?

Accepted Answer

Asymmetry Multiplier (AM)

Answer

The Asymmetry Multiplier (AM) reduces the RWL when there is angular displacement of the load from the sagittal (front) plane, penalizing torso twisting.

Question 4

What is the primary purpose of a 'team lift' protocol?

Accepted Answer

To distribute the load so no single worker exceeds individual capacity

Answer

Team lifts distribute heavy or bulky loads among two or more workers so that each person's share remains within safe individual lifting limits.

Question 5

Which pushing/pulling measurement tool is most commonly used to assess force limits in industrial settings?

Accepted Answer

Dynamometer or force gauge

Answer

A dynamometer or force gauge measures the initial and sustained push/pull forces applied to carts or equipment, which are then compared to Snook tables or Liberty Mutual guidelines.

CES - Certified Ergonomic Specialist Practice Test

CES - Certified Ergonomic Specialist Practice Test

CES Manual Material Handling & Industrial Ergonomics