NIOSH Lifting Index (LI)

NIOSH Lifting Index (LI)

ER-02
ASPCSPFoundational

Formula
LI = L ÷ RWL
When to Use

Assess the physical stress of a lifting task. LI > 1 indicates increased risk of low back injury.

Symbol Legend
SymbolMeaningUnitNote
LILifting IndexLI>1 = increased risk; LI>3 = high risk
LActual object weightkg or lb
RWLRecommended Weight Limitkg or lbFrom NIOSH equation

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