ABSTRACT
Over the last three decades, several low back injury risk assessment tools have been developed to provide
ergonomics practitioners the ability to evaluate the relative risk posed by manual materials handling
(MMH) tasks. The Work Practices Guide for Manual Lifting (NIOSH, 1981) and the Revised NIOSH
Lifting Equation (Waters et al., 1993, 1994) are two well-established methods developed by the National
Institute for Occupational Safety and Health (NIOSH). The Lumbar Motion Monitor (LMM) risk assess-
ment model (Marras et al., 1993) and the Three-Dimensional Static Strength Prediction ProgramTM
(3DSSPP) were developed by researchers at The Ohio State University and the University of Michigan,
respectively. The goals of this paper are to compare and contrast these existing assessment models,
develop the motivation for a hybrid modeling technique and identify gaps in our current low back
injury risk assessment techniques for other high-risk activities.