Firefighters have spent a cumulative 18 months fighting suspicious blazes since 2009, figures reveal.
Fire and Emergency statistics reveal in eight years firefighters across the country battled 12,334 incidents of suspected arson, spending 801,198 minutes putting the fires out.
That's 556 days — or 18 months.
The data represents instances where firefighters attending the scene can see no reason for the fire starting without malicious intent, but in some cases investigators may have determined the fire accidental.
Palmerston North recorded the most suspicious fires, followed by Wainuiomata, and Aranui, in Christchurch.
It is not well understood that once a fire is started, its growth and the damage that follows is out of the control of the fire lighter.
The figures were provided to the Herald on Sunday under the Official Information Act by Fire and Emergency, but it was unable to provide estimates on how much the fires cost to extinguish, saying it didn't keep track of such costs at incident level.
Fire and Emergency national manager of arson reduction and fire investigation Peter Wilding said the figures highlighted "the unnecessary waste and commitment of resources required to deal with these fires which impacts on our ability to respond to other emergencies".
A Tauranga playground destroyed by fire last October. Photo / John Borren
"While we are attending fires caused by arson our fire crews are unavailable for other fires, rescues, medical calls, and hazardous emergencies that occur in communities," he said.
"Where rescues or medical events are involved this could well be the difference between people living or dying."
He said it was common for people apprehended for arson to say they "hadn't intended for a fire to grow so large or cause the level of damage or injuries that occurred".
"It is not well understood that once a fire is started, its growth and the damage that follows is out of the control of the fire lighter."
According to Fire and Emergency the most common place for suspicious blazes was rubbish fires in schools, prompting it to analyse school fires across the country for arson reduction.
They had been able to reduce school arson by 50 per cent, Wilding said.
Fire and Emergency also record unlawful fires — 4413 in the past year — in which people have recklessly started a fire, using fireworks in a forest, say, or lighting fires in banned areas.
Wilding said those figures remained relatively static.
President of Fire Investigators Association of New Zealand Ken Legat said the motives for arson were wide ranging but commonly included profit, crime concealment, revenge, and matrimonial disputes.
A common misconception was that fire destroyed evidence.
In fact, investigators were able to collect DNA and fingerprints even from well involved fires, Legat said.
