Fatigue and Endurance Limits During Intermittent Overhead Work

Details

• Personal Author:
  Clark L ; Kirst M ; Nussbaum MA ; Rice K
• Description:
  Shoulder problems are prevalent in industrial work, particularly when tasks require the hands to be used at or above shoulder level. Although extensive research has been conducted on prolonged static exertions, and several guidelines for such efforts exist, there is insufficient information for ergonomic evaluation of tasks that are intermittent and/or dynamic. A laboratory simulation was conducted of overhead assembly work that was both intermittent and dynamic, and which varied the duty cycle (work/rest ratio), arm reach, and hand orientation of a tapping task. Results consisted of endurance times and also the times of fatigue onset as indicated by perceived discomfort and declines in muscle strength. Females exhibited longer (22%) endurance times, delayed reports of discomfort, and slower declines in strength. Significant influences of duty cycle were found on both endurance and fatigue times, yet arm reach and hand orientation did not have consistent effects. Distributions of endurance and fatigue times are presented as criteria for preliminary evaluation of overhead work. Endurance times could be predicted with only moderate accuracy from earlier indicators of fatigue onset. Existing guidelines, albeit developed for static tasks, appeared unsuitable for the simulated overhead assembly efforts examined. Furthermore, such guidelines may fail to capture the substantial interindividual variability observed in this experiment. [Description provided by NIOSH]
• Subjects:
  Demography Ergonomics Fatigue Laboratories Musculoskeletal System Occupational Health Safety Sex Characteristics
• Keywords:
  Demographic-characteristics Endurance-tests Fatigue-properties Laboratory-testing Muscles Occupational-health Physical-properties Sex-factors Simulation-methods
• ISSN:
  0002-8894
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  OSHA Region 3 ; Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  446-456
• Volume:
  62
• Issue:
  4
• NIOSHTIC Number:
  nn:20031284
• Citation:
  Am Ind Hyg Assoc J 2001 Jul/Aug; 62(4):446-456
• Contact Point Address:
  Industrial and Systems Engineering, Virginia Polytechnic Institute and State University, 250 Durham Hall (0118), Blacksburg, VA, 24061
• Email:
  nussbaum@vt.edu
• Federal Fiscal Year:
  2001
• Performing Organization:
  Virginia Polytechnic Institute and State University, Blacksburg
• Peer Reviewed:
  True
• Start Date:
  20010701
• Source Full Name:
  American Industrial Hygiene Association Journal
• End Date:
  20260630
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:fe75de4dc6ac7c40212730c242d52c60a40ed29ec36590d92612b1badae62ff384489a2c88063befeb56b829aff1aa2bcab6d48587625fc454d1a14d6bc16829
• Download URL:
  https://stacks.cdc.gov/view/cdc/191578/cdc_191578_DS1.pdf
• File Type:
  [PDF - 699.02 KB ]