title: Task parameters affecting ergonomic demands and productivity of HVAC duct installation.
abstract: BACKGROUND
  Mechanical installation workers experience work-related musculoskeletal disorders (WMSDs) at high rates.
  
  
  OBJECTIVE
  (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.
  
  
  METHODS
  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.
authors.affiliation: Department of Civil, Construction and Environmental Engineering, San Diego State University, San Diego, CA, USA.
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Mitropoulos
authors.affiliation: School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, AZ, USA.
authors.forename: Sanaa
authors.initials: S
authors.lastname: Hussain
authors.affiliation: Occupational Safety and Health, Gateway Community College, Phoenix, AZ, USA.
authors.forename: Linda
authors.initials: L
authors.lastname: Guarascio-Howard
authors.affiliation: School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, AZ, USA.
authors.forename: Babak
authors.initials: B
authors.lastname: Memarian
mesh_terms: D000389:Air Conditioning / Q000009:adverse effects* / Q000379:methods; D004526:Efficiency / Q000502:physiology; D005260:Female; D006361:Heating / Q000009:adverse effects* / Q000379:methods; D006801:Humans; D008297:Male; D060051:Occupational Injuries / Q000453:epidemiology / Q000209:etiology*; D011187:Posture / Q000502:physiology; D012307:Risk Factors; D013647:Task Performance and Analysis
keywords: Mechanical installation; musculoskeletal disorders; postural analysis