January 16, 2025
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How will fire investigators trace the source of the LA fires?
The fires in Los Angeles destroy so much, but often ignore some evidence of the cause of the fire.
A firefighting helicopter drops water from the Mandeville Canyon neighborhood and Encino, California on January 11, 2025.
Patrick T. Fallon/AFP via Getty Images
As the firemen continue fight fires With thousands of structures destroyed in the Los Angeles area, fire investigators are already trying to figure out how the fires started.
Local news agencies have reported that investigators are closing streets in the Palisades Highlands, the Los Angeles area where the Palisades Fire, the region’s largest wildfire, started. The investigation is in its early stages, but officials will be able to find the cause, as they have done in other fires. Fires can start in a number of ways: naturally, with lightning, or, more often, with the help of others human related means—for example, sparks from a downed power line, a discarded cigarette butt, a poorly extinguished fire, or even a fire. Between 1992 and 2012, 84 percent of all fires in the US were caused by humans.
Since there were no lightning storms in the LA area when the fire started, investigators will look for human-related causes. A first point of interest is around Skull Rock, a landmark near a popular hiking trail above the Palisades Highlands, according to reporters who saw it. crime scene tapepolice and roads near closed roads. There was a small fire on New Year’s Day that quickly extinguished the place. The fire may leave embers that can be fanned by the wind, but Skull Rock is also home to power lines and heavy human traffic, leaving multiple options open. (See photos of the Los Angeles fires)
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Meanwhile, the investigation into the Eaton fire, the second largest in recent wildfires in the LA area, is currently focused on electrical transmission equipment in Eaton Canyon. according to Los Angeles Times.
Bob Duval is a fire investigator and regional director for the National Fire Protection Association (NFPA), an international non-profit organization that publishes the document. NFPA 921: Fire and Explosion Investigation Guide. It’s the closest thing to a Bible that fire investigators have, with instructions on how to find the cause of anything from a house fire to a fire that burns through miles of forest. He talked to Duval American scientific About how to investigate fires like the one that destroyed the Los Angeles area.
(Following is an edited transcript of the interview.)
How would one normally begin an investigation like what is happening now in the LA region?
If it’s in a populated area, you may have eyewitness accounts from a driver who saw some. flames or smoke next to the road Highways may have surveillance cameras or traffic cameras. You have pilots, commercial airliners. Can you determine based on eyewitness accounts or eyewitness accounts of a power grid suddenly showing a fault? If it’s thousands of acres, can I reduce it to 10 or 15 acres on the side of this mountain or street and then take it from there? You have to be systematic.
And then people will enter the field. You look at the patterns. From which direction did the fire come? You look at a big tree. Which side of the tree was burned? Is the burn pattern going up or down? Look for them on the barrel, pine needles or leaves. What does it show about the direction of the fire? Then you will study the topography: the wind on one side of a hill is different from the wind on the other side. You have canyons, you have roads that all affect how fire spreads.
By systematically collecting all this evidence, you are going back to where the fire started. And then you start looking for causes in that area.
You think a fire destroys everything, but it seems some evidence may be left behind.
It is a common misconception that everything is destroyed with a fire investigation. Therefore, people are under a misunderstanding that if they commit a crime, they can try to cover it up by setting the building on fire. Yes, this may hide some evidence, but it also creates a lot of evidence.
For a campsite (that burned out of control), for example, you’re looking for: Did they pile up wood or brush or twigs? Did they throw away the paper? Did they put rocks around it to hold it? You would find the ground sealed as if people had been there for some time.
Is the road commonly used by motorcycles or ATVs (all-terrain vehicles) with any evidence of smoking? Was someone cleaning the brush? Was anyone out shooting or hunting where a spark from a firearm or a hot shell could cause (fire) Does anyone report hearing or seeing fireworks in the area?
Another potential cause is fire. That can be a bit more difficult. If it’s a lighter, someone could put it in their pocket and walk out of the woods. A fire can remain undetermined, which is the official term used when we have an area of origin but cannot find the cause.
Is there a difference between investigating wildfires, such as the LA fires, and fires that start in a building?
Yes and no These two areas create patterns, and the researcher uses the patterns to help determine the area of origin. In a building, it has several compartments if you think of a house or apartment. But in a fire, there are no compartments. It is open. There is unlimited air. Wind can affect a building fire. But in the desert the wind is the main factor because it drives everything you do There have been many deaths there extinguishing forest fires because the wind pushes the fire and overwhelms the firefighters.
How long does an investigation usually take?
It could be months. I think the people of California have done their job. There are different reviews that the report needs to go through. They want to make sure everything is done as well as it can be done. (That doesn’t mean the process) should be different if it’s a $10 fire or a $100 million fire. Research should still be done systematically and in books. But you can imagine the scrutiny these reports will have, because there is a possibility of civil damages here.
