Affiliations: Department of Civil, Construction and Environmental Engineering, San Diego State University, San Diego, CA, USA | School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, AZ, USA | Occupational Safety and Health, Gateway Community College, Phoenix, AZ, USA
Note: [] Corresponding author: Panagiotis Mitropoulos, Department of Civil, Construction and Environmental
Engineering, San Diego State University, 5500 Campanile Dr., San Diego, CA 921278, USA. Tel.: +1 619 594 0137; E-mail: pmitropoulos@mail.sdsu.edu
Abstract: 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.
