Wesley G. Page

An empirically based approach to defining wildland firefighter safety and survival zone separation distances

Wildland firefighters in the US are mandated to identify areas that provide adequate separation between themselves and the flames (i.e. safety zones) to reduce the risk of burn injury. This study presents empirical models that estimate the distance from flames that would result in a low probability (1 or 5%) of either fatal or non-fatal injuries. The significant variables for the fatal injury model were fire shelter use, slope steepness and flame height. The separation distances needed to ensure no more than a 1 or 5% probability of fatal injury, without the use of a fire shelter, for slopes less than 25% were 20 to 50 m for flame heights less than 10 m, and 1 to 4 times the flame height for flames taller than 10 m. The non-fatal injury model significant variables were fire shelter use, vehicle use and fuel type. At the 1 and 5% probability thresholds for a non-fatal injury, without the use of a fire shelter, the separation distances were 1 to 2, 6 to 7, and 12 to 16 times greater than the current safety zone guideline (i.e. 4 times the flame height) for timber, brush and grass fuel types respectively.

Fuel and topographic influences on wildland firefighter burnover fatalities in Southern California

Previous reviews of wildfires where a fatal firefighter burnover occurred have found that the incidents usually share similar characteristics in terms of the fire environment, such as steep slopes and complex topography (e.g. box canyons). Despite these similarities, systematic identification and communication of the locations where these conditions prevail are rare. In this study we used a presence-only machine-learning algorithm (Maximum Entropy, MaxEnt) coupled with spatial location information from past fatal firefighter burnovers to identify and characterise the environmental variables that are likely to produce conditions suitable for a fatal burnover. Southern California was chosen to conduct the analysis as it has a well-documented history of past fatal firefighter burnovers and a complex fire environment. Steep, south-west-oriented slopes located in canyons with a shrub fuel type were found to be the most dangerous locations for firefighters. The relative danger to firefighters from a fatal burnover is described and summarised at both the 30-m pixel and local watershed scale.

An Evaluation of NDFD Weather Forecasts for Wildland Fire Behavior Prediction

AbstractWildland fire managers in the United States currently utilize the gridded forecasts from the National Digital Forecast Database (NDFD) to make fire behavior predictions across complex lands...