Isolate and Fix the Ergonomic Issues of Moving a Box from a Conveyor to a Pallet

Executive Summary

This study aims to isolate and fix the ergonomic issues that are associated with moving a box from a conveyor to a pallet. The objective is to figure out a way for this job to have acceptable work conditions according to the NIOSH lifting guidelines which should greatly decrease the number of workplace injuries due to ineffective ergonomic design.  This study was performed by making calculations about the RWL, LI, and CLI of the original design to find out exactly what needed to be fixed in the redesign. The original job had CLI of 3.40  which is unacceptable as the CLI must be <1 or the work conditions to be deemed safe. Our final redesign had a CLI value of 0.96 which constitutes acceptable working conditions improving the safety of the task dramatically. This redesign will keep the same functionality and productivity of the old design but will reduce injury potential drastically!  

Introduction: 

        The problem we were given for this lab was the action of a worker lifting a box off of a conveyor belt and then placing the box onto a pallet that contained more boxes. The worker is assigned to taking a box off of a conveyor belt that is 27 inches in height and then placing it on a pallet that is 13 inches in height. The boxes’ dimensions consist of 20” x 16” x 8” and weigh 23 pounds. The worker is able to move 5 boxes per minute for a full hour shift. The pallet consists of four layers of boxes with 12 boxes per layer. This job shows the characteristics of a job containing overexertion injuries. Overexertion injuries from lifting account for 25% of the industrial accidents, which accounts for 12 million lost days and $14 billion in costs. The main focus of this study is to eliminate any factors that lead to these type of injuries. When looking at these factors, a better way of doing the task will not only reduce injuries but also fulfill the NIOSH lifting guidelines. Fixing these problems now will lead to less money needed for injuries in the future. This saves not only the company money, but also the workers lives.

Objectives:

        The objective of this case study is to decrease the amount injuries that occur from overexertion and find what is acceptable for the NIOSH lifting guidelines. The Composite Lifting Index for this job will be calculated and analyzed to see if it is acceptable for the job. Since it is suspected that this work is unacceptable, the task of redesigning the job will come into play. This will be done by trying to get all the multipliers that are used in the Recommended Weight Limit equation to be as close to 1 as they can get. By doing this, in return the smallest CLI will be obtained. As long as the CLI is less than 1, the job is deemed to be acceptable. A 3D Static Strength Prediction Model will then be used to help assist in improving the job.