産業医学および健康問題

抽象的な

Frequency, Intensity, Time And Type Of Tasks Performed During Wildfire Suppression

Matthew Phillips, Kevin Netto, Warren Payne, David Nichols, Cara Lord, Neil Brooksbank and Brad Aisbett

Objective: To quantify the frequency, intensity, duration, and type of tasks performed by Australian rural fire crews when suppressing wildfires.

Methods: Twenty-eight Australian rural firefighters worked across four, six-hour shifts fighting to curtail the spread of wildfire. Each firefighter wore a heart rate monitor and personal global positioning system (GPS) unit and was followed by a researcher filming their work activity. Video footage of each firefighter was synchronized with their heart rate and GPS data to quantify the frequency, intensity and duration of individual fireground tasks. Fireground tasks were isolated using a previously conducted job task analysis.

Results: Firefighters performed 32 distinct fireground tasks. Task frequencies ranged from once to 103 times per six-hour shift. Individual tasks lasted 4 ± 2 s to 461 ± 387 s, were performed at speeds ranging from 0.12 ± 0.08 m•s-1 to 0.79 ± 0.40 m•s-1 and elicited mean heart rates that ranged between 97 ± 16 beats•min-1 (55.7 ± 8.7 percentage of age-predicted maximum heart rate (HRmax)) and 157 ± 15 beats•min-1 (86.2 ± 10.8%HRmax).

Conclusion: Fireground tasks were, generally speaking, shorter, slower, and elicited lower heart rates than equivalent tasks previously simulated and reported in the literature. The differences between naturally occurring and simulated tasks question the value of isolated task simulations for conducting physical demands analyses en-route to developing job-specific fitness tests.