Modeling the impact of the components of long work hours on injuries and “accidents”

Authors

  • Simon Folkard PhD, DSc (Lond),

    Corresponding author
    1. Université Paris Descartes, Faculté de Médecine, Laboratoire d'Anthropolgie Appliquée, Paris, France
    2. Body Rhythms and Shiftwork Centre, University of Wales Swansea, Swansea SA2 8PP, United Kingdom
    3. Liberty Mutual Research Institute for Safety, Hopkinton, Massachusetts
    • Université Paris Descartes, Faculté de Médecine, Laboratoire d'Anthropolgie Appliquée, UPRES Ergonomie, 45 rue des Saints Pères, 75006 Paris, France.
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  • David A. Lombardi PhD (Mass)

    1. Liberty Mutual Research Institute for Safety, Hopkinton, Massachusetts
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Abstract

Background

Many of the industrial disasters of the last few decades, including Three Mile island, Chernobyl, Bhopal, Exxon Valdez, and the Estonia ferry, have occurred in the early hours of the morning. Follow-up investigations concluded that they were at least partially attributable to human fatigue and/or error. The potential impact of long work hours on health and safety is a major concern that has resulted in various work hour regulations.

Methods

The risk of injuries and “accidents” (incidents) associated with features of work schedules from published epidemiological studies are pooled using an additive model to form a “Risk Index.” The estimated risks of an incident for various standard work schedules are presented using the proposed model.

Results

The estimated risk of an injury or accident associated with any given number of weekly work hours varies substantially depending on how work hours are comprised. The risk depends on the length and type of shift, as well as the frequency of rest breaks.

Conclusions

We conclude that placing a limit on the risk associated with a particular work schedule is likely more effective than setting daily, weekly or monthly work hour regulations in keeping workplace safety within acceptable limits. Am. J. Ind. Med. 2006. © 2006 Wiley-Liss, Inc.

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