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International Journal of Wildland Fire International Journal of Wildland Fire Society
Journal of the International Association of Wildland Fire
RESEARCH ARTICLE

Using a biomathematical model to assess fatigue risk and scheduling characteristics in Canadian wildland firefighters

Andrew T. Jeklin https://orcid.org/0000-0001-7627-7792 A C , Hugh W. Davies B , Shannon S. D. Bredin A , Andrew S. Perrotta D E , Benjamin A. Hives https://orcid.org/0000-0001-8874-8678 A , Leah Meanwell A and Darren E. R. Warburton A E F
+ Author Affiliations
- Author Affiliations

A School of Kinesiology, University of British Columbia, Vancouver, BC V6T 1Z1, Canada.

B School of Population and Public Health, University of British Columbia, Vancouver, BC V6T 1Z3, Canada.

C School of Medicine, Monash University, Melbourne, Vic. 3800, Australia.

D Department of Kinesiology, Langara College, Vancouver, BC V5Y 2Z6, Canada.

E Experimental Medicine Program, Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z2, Canada.

F Corresponding author. Email: darren.warburton@ubc.ca

International Journal of Wildland Fire 30(6) 467-473 https://doi.org/10.1071/WF20094
Submitted: 17 June 2020  Accepted: 16 March 2021   Published: 16 April 2021

Abstract

This study examined the shift parameters that contribute to sleep loss and on-duty fatigue in British Columbia Wildfire Service (BCWS) firefighters using sleep–wake data, work–rest data and alertness and fatigue predictions from a biomathematical model (BMM) of fatigue. A total of 40 firefighters (age: 30.4 ± 11.6 years; 13 F, 26 M) volunteered over a 14-day consecutive fireline deployment, followed by a 3-day rest period, at two separate fires in British Columbia (during the 2015 fire season). Sleep–wake data were obtained using a wrist-worn accelerometer and self-reported sleep logs. Shift start and end times were provided by the BCWS at the completion of the study. Sleep and shift data were manually entered into a validated BMM (Circadian Alertness Simulator) to generate fatigue scores and shift work patterns. Shift duration was the major contributor to fatigue, as 46% (n = 274) of shifts were ≥14 h in length and the average shift length was 13.0 ± 0.62 h. However, none of the firefighters had a high-risk fatigue score (>60). The findings from this study indicated that using a BMM of fatigue can provide important insights into shift-work parameters that contribute to workplace fatigue and sleep loss in wildland firefighters.

Keywords: fatigue, fatigue model, shift work, sleep deprivation, wildland firefighters.


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