Ergonomics: Evaluation of Muscular Stress in Construction Machine Operators an EMG Study

Details

• Personal Author:
  Anderson B ; Norlander S ; Schneider S ; Wos H
• Description:
  In their work, operators of wheeled construction machines run the risk of being afflicted with ailments localized in the musculoskeletal system, which are often caused by poor working postures in the cab as well as repeated, uncomfortable, and physically stressing operating maneuvers. Poor visibility is one of the risk factors. The visual demands determine the working posture and, as a consequence, the driver may not be able to utilize the ergonomic properties of the cab. Visibility improvements are very important measures that ought to be prioritized, partly to meet comfort and safety requirements, but also to increase the productivity of the machines. The aim of this study was to arrive at an objective evaluation of the muscular stress on the shoulders and lumbar region of wheeled loader operators in the performance of 10 representative maneuvers. The measurements were recorded during the operation of an older cab model and Volvo BM's new Care Cab which has been designed to achieve even better driver comfort. Among other things, the window surface area has been increased by about 50 percent, and a new steering system confers ergonomic advantages. The study has shown that the stress on the muscles of the lumbar region decreased on both the right and left side in the new cab as a consequence of ergonomic improvements. Similarly, there was a decrease in the so-called stress dose in the shoulders in the new cab, whereas the level of stress in the left shoulder increased due to an unfavorable positioning of the driver's wheel. The most important individual factor in the improved ergonomics of the new cab is the very large visibility increase. The increased proportion of glass surface area makes it possible to utilize the supporting surfaces and backrest of the driver's seat to a higher degree than in the old cab, with reduced muscular stress as a result. The driver has a wider view of the operating area of the machine and loading apparatus from his position in the new cab. The results show that VME's investments in a more ergonomically correct cab have been successful because muscular stress has been reduced to a considerable extent. Furthermore, the study of stress conditions has produced results that will enable the designers to make further improvements in the cab. The project has generated several ideas for future development. [Description provided by NIOSH]
• Subjects:
  Construction Industry Ergonomics Manufacturing And Industrial Facilities Musculoskeletal Diseases Occupational Health Safety
• Keywords:
  Construction Industry Equipment Operators Machine Operators MSD Musculoskeletal Disorders
• ISSN:
  1047-322X
• Document Type:
  Text
• Funding:
  Cooperative Agreement
• Genre:
  Journal Article
• Place as Subject:
  District of Columbia ; OSHA Region 3
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  161-169
• Volume:
  10
• Issue:
  3
• NIOSHTIC Number:
  nn:20055338
• Citation:
  Appl Occup Environ Hyg 1995 Mar; 10(3):161-169
• Contact Point Address:
  Scott Schneider, CIH, Center to Protect Workers' Rights, 111 Massachusetts Avenue NW, Washington, DC 20001
• Federal Fiscal Year:
  1995
• Performing Organization:
  Center to Protect Workers' Rights
• Peer Reviewed:
  True
• Start Date:
  19920930
• Source Full Name:
  Applied Occupational and Environmental Hygiene
• End Date:
  19950929
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:0c37f56f4e54df32fb15833103792340234a7fdb994f591eb914a149e54617b3c30555e4c565f01c4ad4c26c5701a107d850150de4cda20c1f612cb5ef470246
• Download URL:
  https://stacks.cdc.gov/view/cdc/217670/cdc_217670_DS1.pdf
• File Type:
  [PDF - 1.30 MB ]