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The estimated national burden of physical ergonomic hazards among US workers
Sangwoo Tak1, Geoffrey M Calvert
1National Institute for Occupational Safety and Health, Cincinnati, Ohio 45226, USA. stak@cdc.gov
Purpose:
To estimate the national burden of physical ergonomic hazards among working adults in the US.
Methods:
We estimated the population prevalence of and the total number of workers who are exposed to physical ergonomic hazards, such as vibration, working in cramped space, kneeling, body bending or twisting, climbing, and repetitive motions using Occupational Information Network (O*NET) data and the Occupational Employment Statistics (OES) from the U.S. Bureau of Labor Statistics (BLS) stratified by occupation title.
Results:
Repetitive motion was the most prevalent of all ergonomic hazards (27% of US workers are estimated to be exposed continually). Bending or twisting of the body more than half their time at work was also common, involving over 32 million US workers (25% of US workforce). Kneeling, crouching, stooping, or crawling was another ergonomic hazard that 14 million US workers perform more than half their time at work. Almost 4 million workers climb ladders, scaffolds, poles, etc. for more than half their time at work. We estimate that over 13 million workers (10% of US workforce) were exposed to cramped workspace that requires getting into awkward positions every day. Finally, about 3.5 million workers (2.7% of US workforce) were estimated to be exposed to whole body vibration every day.
Conclusion:
A large portion of the US work force is exposed to ergonomic hazards known to be associated with musculoskeletal disorders (MSDs). The occupations with the highest prevalence of each ergonomic hazard may be deserving of prompt efforts toward prevention of MSDs.
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