Addressing Ergonomic Issues in Concrete Pouring: The Integration of Engineering Controls to Mitigate Cumulative Stress Disorders

Abstract

The purpose of this study was to analyze the work practices of cement finishers who manually clean concrete transfer tubing at various Company XYZ worksites. The goal of the study was to assess an initial lifting task in order to quantify employee exposure during the cleaning of flexible concrete slurry transfer tubing. Using observation-based methods to collect posture, force, repetition, duration and temperature data, this study applied recognized quantitative and qualitative ergonomic techniques which included the Liberty Mutual Snook Tables (Liberty Mutual Insurance, 2012) and the Revised National Institute for Occupational Safety and Health (NIOSH) Lifting Equation to evaluate the frequency and severity of the lifting activity. A Wagner FDL force gauge indicated the lifting weight was approximately 90 pounds. During this initial lifting task, the hip and spine flexion was found to be 105 degrees while shoulder forward flexion was found to be 105 degrees. Additionally, the Liberty Mutual Snook Tables (Liberty Mutual Insurance, 2012) revealed less than ten percent of both the male and female populations could perform this lifting task. The results of the Revised NIOSH Lifting Equation analysis determined a recommended weight limit (RWL) of 26.91 pounds with a Lifting Index (LI) of 3.34 indicated an elevated risk of back and/or shoulder injury. Recommended risk reduction approaches include the use of various devices to assist with lifting the tubing to reduce weight and improve the posture during the lift. Job rotation practices, lighter weight tubing and alternative clamping devises were also recommended.