Video-based Ergonomic Risk Assessment among Transportation Maintenance Workers in Shoveling

Abstract

Shoveling is a physically demanding task that has resulted in various physical injuries, particularly affecting workers’ lower backs and shoulders. Specifically, shoveling gravel has been identified as one of the primary activities leading to common ergonomic injuries among transportation maintenance workers. Previous research has focused on evaluating the risks of ergonomic injuries from shoveling through simulations in the construction industry and field experiments in the agricultural industry. However, there is a lack of studies about the ergonomic risks associated with shoveling activities by field experiments within the transportation industry. In addition, prior studies have proposed some ergonomic solutions to prevent injuries in shoveling activity, such as ergonomic handles and back exoskeletons (EXOs). However, no research has yet provided a direct comparison of ergonomic risk levels when workers utilize different ergonomic solutions while shoveling. To address these gaps, this research evaluated the ergonomic risk levels associated with shoveling activity using different ergonomic solutions among 26 transportation maintenance workers. The ergonomic risk evaluation was conducted using the Rapid Entire Body Assessment (REBA) and Rapid Upper Limb Assessment (RULA) methods based on videos of their shoveling activities. Videos were recorded from October 3rd to October 17th, 2022. Each participant completed four trials of shoveling gravel, averaging around 97 minutes, using a regular shovel, a back EXO, an ergonomic handle, and both the back EXO and the ergonomic handle. Between each two subsequent trials, a 15-minute break was provided for participants to recover from the previous trials. Moreover, participants finished the four trials of shoveling gravel following the Balanced Latin Square order, in order to avoid the carry-over and order effects. During each trial, participants first shoveled broken gravel from the ground to the skid steer loader and cleaned any residual gravel from the ground in Part 1. Then, they shoveled new gravel from the asphalt hot box machine to the ground and patched it in Part 2. A 5-minute break between Part 1 and Part 2 was also offered to simulate the real-life practice. Results found that wearing a back EXO did not significantly reduce ergonomic risks during shoveling gravel, whereas the use of ergonomic handles and the combined use of the back EXO and ergonomic handle significantly decreased ergonomic risk scores during shoveling gravel. This study not only fills the gaps of ergonomic risk evaluation in real-world transportation maintenance activities, but also provides valuable insights for enhancing worker safety and efficiency in such environments.