title: Production practices affecting worker task demands in concrete operations: A case study.
abstract: BACKGROUND
  Construction work involves significant physical, mental, and temporal task demands. Excessive task demands can have negative consequences for safety, errors and production.
  
  
  OBJECTIVE
  This exploratory study investigates the magnitude and sources of task demands on a concrete operation, and examines the effect of the production practices on the workers' task demands.
  
  
  METHODS
  The NASA Task Load Index was used to measure the perceived task demands of two work crews. The operation involved the construction of a cast-in-place concrete building under high schedule pressures. Interviews with each crew member were used to identify the main sources of the perceived demands. Extensive field observations and interviews with the supervisors and crews identified the production practices.
  
  
  RESULTS
  The workers perceived different level of task demands depending on their role. The production practices influenced the task demands in two ways: (1) practices related to work organization, task design, resource management, and crew management mitigated the task demands; and (2) other practices related to work planning and crew management increased the crew's ability to cope with and adapt to high task demands.
  
  
  CONCLUSIONS
  The findings identify production practices that regulate the workers' task demands. The effect of task demands on performance is mitigated by the ability to cope with high demands.
authors.affiliation: Exposure Control Technologies Research, CPWR - The Center for Construction Research & Training, Silver Spring, MD, USA.
authors.forename: Babak
authors.initials: B
authors.lastname: Memarian
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
mesh_terms: D060389:Construction Industry / Q000379:methods* / Q000458:organization & administration*; D003252:Construction Materials; D006801:Humans; D016272:Occupational Health; D009790:Occupations; D010465:Perception; D011795:Surveys and Questionnaires; D016526:Workload; D017132:Workplace / Q000458:organization & administration*
keywords: NASA-TLX; Production system design; construction, concrete; task demands; worker