Calculation Tools


NIOSH Lifting Equation report excerpt

Benchmark ergonomic risk levels, focus on specific task details and perform "what-if" analyses

NIOSH Lifting Equation

The NIOSH lifting equation is used to evaluate a manual lifting task to determine the Recommended Weight Limit (RWL) and the Lifting Index (LI).

The interactive tool allows you to perform "what if" analysis of lifting factors by changing variables to determine optimal lifting limits.

Analysis factors include:

  • Object weight
  • Hand location (origin and destination)
  • Lift angles
  • Frequency rate
  • Duration
  • Object coupling
Strain Index report excerpt

Strain Index

Does the job impose a risk for arm/hand musculoskeletal disorders? Use the Strain Index* to determine the combined effect of exertions, frequency, posture, speed and duration. Scores greater than or equal to 7 have been associated with arm/hand musculoskeletal disorders.

*Moore, JS, and Garg, A: The strain index: a proposed method to analyze jobs for risk of distal upper extremity disorders, Am. Ind. Hyg. Assoc. J. (56), May 1995: 443-455.