The article below, dated January 8, 2015, was written by Justin Leonard, of Commonwealth Scientific and Industrial Research Organisation (CSIRO) in Australia.
****
The latest round of bushfires, which claimed 27 homes in the Adelaide Hills, has once again highlighted the importance of planning for the worst. Mercifully, no human lives were lost, and it will be important to learn whatever lessons we can to avoid future tragedies.
My colleagues and I analysed 825 deaths in 260 Australian bushfires from 1901 to 2011, and our research has revealed some compelling evidence to help guide residents to plan for future bushfires.
Most people (58%) lost their lives when caught out in the open. Strikingly, 72% of those people were within 200 m of their own homes (this statistic is based only on cases where details are accurately known).
I encourage you to imagine what circumstances and decisions might have led to these outcomes. Do a large number of people simply wait to see if the fire is really going to arrive on their doorstep?
Bushfire deaths within a house are most prevalent during our most severe fire events, representing 75% of all fatalities during bushfires that occurred on days with “catastrophic” (code red) fire danger conditions. This is despite them representing only 27% of all bushfire deaths.
Of those who died inside homes, 92% were in rooms that did not have a door that led directly to the exterior of the house (once again, this is based only on cases where circumstances are accurately known). This raises uncomfortable questions: why did these people apparently not try to leave the home as the house fire developed? Were they monitoring the conditions outside as the fire passed? Had they thought about which exit was the safest?
Homes under attack
When a fire arrives at a property, the house will experience “ember attack”. This attack is strongest as the main fire arrives and will persist for a long time after it has passed, and may also start to happen before the fire actually arrives. If the house is close enough to the bush it may also be affected by radiant heat, and if very close then direct flame contact is possible, although most houses are lost without any direct interaction from a bushfire front – which goes some way to account for the seemingly random loss patterns that occur.
Continue reading “Bushfires kill, but knowing exactly how might make them less deadly”