Case Study: An Application of the Revised NIOSH Lift Guide to a Multiple Task Job

Abstract

The newly revised NIOSH lifting guide offers a multiple task strategy for frequency weighting multiple lifting tasks performed in a series; in close proximity of time. This strategy allows calculation of a composite lifting index (CLI) during assessment of jobs for which lifting variables are changing throughout the task. While the approach is useful, the number of calculations and table look-up procedures required is much larger than a single task strategy requires, and the process becomes tedious and error prone if performed manually. Consequently, a computer program was developed by Continental Insurance Corporate Loss Control in FORTRAN to automate table look-ups and required calculations. A case-study applying the multi-task approach to an actual job is shown. The job involves manual lifting/lowering of boxes from a queuing turntable to a pallet stack. The results indicate that the job is unacceptably hazardous, which agrees with subjective responses of workers. Possible worksite retrofit changes are also evaluated in a “what-if” manner. These results show that changes would improve the risk level, but proposed improvements were not sufficient to attain an acceptable risk level. Mechanization of the job is therefore suggested. Details regarding the multi-task application are discussed.