Are posture data from simulated tasks representative of field conditions? Case study for overhead electric utility workers

Many ergonomics studies are conducted in laboratory-simulated work environments to assess risks for the development of musculoskeletal disorders under more controlled conditions. However, the simulated conditions could be of questionable validity with respect to reproduction of field conditions involving risk factors. The objective of this study was to verify whether the postures recorded for neck extension/flexion and upper arm elevation of overhead electric utility workers in a simulated environment were similar to those recorded in a field environment. Of the three frequently performed tasks analysed, two presented similar exposure in both conditions. However, differences were identified for a more complex task (relay replacement). These results suggest that simulated tasks may be more representative for more standardised tasks. This may indicate that researchers investigating risks should avoid simplifying complex tasks when reproducing field posture exposure in laboratories, since omitting extra subtasks may lead to an inaccurate reproduction of field exposure.

Practitioner Summary: Studies comparing results from field and simulated environments are necessary to evaluate to what degree postural exposure reproduced in laboratory is representative of the exposure occurring in real work situations. This is particularly relevant for tasks involving training in simulated environment due to safety constraints.

Keywords:

• work-related musculoskeletal disorders
• laboratory simulation studies
• postural exposure
• inclinometers

Acknowledgements

The authors thank the following agencies for partial financial support: the Coordination for the Improvement of Higher Education Personnel (CAPES/PNPD, Process Number 23038.006938/2011-72), the São Paulo Research Foundation (FAPESP, Process Number 2008/10372-4 and 2008/10399-0) and the National Counsel of Technological and Scientific Development (CNPq, Process Number 301772/2010-0).