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Published on: August 19, 2019
Task parameters affecting ergonomic demands and productivity of HVAC duct installation
Panagiotis Mitropoulos1, Sanaa Hussain2, Linda Guarascio-Howard3
1Department of Civil, Construction and Environmental Engineering, San Diego State University, San Diego, CA, USA.
Background:
Mechanical installation workers experience work-related musculoskeletal disorders (WMSDs) at high rates.
Objectives:
(1) Quantify the ergonomic demands during HVAC installation, (2) identify the tasks and task parameters that generated extreme ergonomic demands, and (3) propose improvements to reduce the WMSDs among mechanical workers.
Method:
The study focused on installation of rectangular ductwork components using ladders, and analyzed five operations by two mechanical contractors. Using continuous time observational assessment, the videotaped operations were analyzed along two dimensions: (1) the production tasks and durations, and (2) the ergonomic demands for four body regions (neck, arms/shoulders, back, and knees). The analysis identified tasks with low portion of productive time and high portion of extreme postures, and task parameters that generated extreme postures.
Results:
Duct alignment was the task with the highest portion of extreme postures. The position of the ladder (angle and distance from the duct) was a task parameter that strongly influenced the extreme postures for back, neck and shoulders. Other contributing factors included the difficulty to reach the hand tools when working on the ladder, the congestion of components in the ceiling, and the space between the duct and the ceiling.
Conclusions:
The identified tasks and factors provide directions for improvement.
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