Cause of blaze that killed two KC firefighters slowly emerging as investigation enters third week

Two weeks after two Kansas City firefighters died in a building collapse, investigators continue to look for the spot where the blaze started inside the three-story structure on Independence Avenue.

Finding the fire’s “seat,” as investigators call it, is pivotal in determining how it ignited — and whether a criminal act, such as arson, led to the death of two Kansas City firefighters.

Federal specialists called in to assist local investigators have declined to speculate. But they hope to announce late this week what causes they have ruled out in the Oct. 12 blaze at 2608 Independence Ave. Firefighters John Mesh and Larry Leggio died after the building’s east wall collapsed into an alley where the firefighters stood.

Finding answers can be difficult after a fire burns much of the evidence, experts told The Star.

Investigators draw clues from many sources: Cellphone and surveillance videos. Smoke, burn and collapse patterns. Damage to support pillars, electrical wiring and even household appliances. Recollections from the residents who fled the building and the firefighters who entered it.

Local investigators sought help from a Bureau of Alcohol, Tobacco, Firearms and Explosives national response team because of the team’s 37-year expertise in finding answers. The Independence Avenue fire is its 775th incident.

“Each event is unique and it’s hard to compare one to the other,” said Chris Porreca, an ATF national response team supervisor and a veteran of more than 50 large deployments.

In this case, investigators focused first on the structure’s east side, where the fatal collapse occurred. While some workers examined bricks and other debris, others poked through the wreckage with shovels and garden rakes, looking for items of interest.

“We put our hands on everything that comes out of the scene,” Porreca said.

Key clues might be found anywhere.

“The smallest items might be of great interest,” said Mike Vergon, a retired ATF certified fire investigator who operates the Indiana-based fire investigation firm Vergon & Associates.

“They are looking for anything that might suggest that it could be something other than accidental.”

The science of fire investigation

Investigators often examine the depth of charred material across the site, which can indicate how long the fire burned in different spots.

They also may look for patterns in which walls fell and which remained standing.

Fire dynamics, or how fire tends to move, also feed into the investigation.

“Generally, fire goes up,” said Richard Meier, an investigator at the National Association of Fire Investigators in Florida. Many carbon-based everyday items, made of wood or paper, burn readily, sending heat and gases upward until they hit a ceiling. Then the fire moves sideways.

Tracing the movement of flames helps investigators find a fire’s starting point.

“Once you get to the place where you think the fire started, then you’ve got to look for how did the fire start,” said Richard Lehmann, former Liberty fire chief and now chairman of the fire service administration program at Johnson County Community College.

“What was the material first burnt, as we call it?”

Then the question is: What lit that material on fire?

Answers are found in 75 to 85 percent of cases, Meier said.

In the emergency dispatch recordings from the fire, a 911 caller reported that the fire “smells like an electrical fire.”

Often, electrical causes are among the last to be ruled out, said John Ham, Bureau of Alcohol, Tobacco, Firearms and Explosives spokesman.

A crew from KCP&L helped investigators understand the electrical system of the building, which dated to the 1920s. Also last week, investigators working their way through debris from the building’s residential apartments collected scorched and twisted household electrical appliances.

At least one ATF team member on the site is an electrical engineer.

“The electrical engineer will look at each one of those appliances checking for evidence of malfunction,” said Vergon, the Indiana-based fire investigator.

A process called “arc mapping” also could help investigators discern the fire’s path. As fire eats away on an energized electrical circuit, it will burn through the insulation on wires, causing them to touch and short-circuit.

“By tracking or mapping out the electrical activity … you can actually map out the fire and get closer to its origins,” Vergon said.

When the investigation wraps

The possibilities for the fire’s cause remain numerous, Ham said.

“We’re looking for a source and we’ll find the source wherever it may be,” Ham said. “It’s a blank page.”

A final report from the ATF team remains months away, he said. It could be months before other reports involving what happened are released as well.

Even if no cause is found, investigators expect to learn a lot about how the building burned and collapsed — and that will add to a growing body of knowledge regarding fire science and fire-fighting safety.

Kansas City Fire Chief Paul Berardi alluded to that at the public memorial for the fallen firefighters when he said, “KCFD will remain strong, we will learn from the incident, and we will teach what we learned.”

The department, like the public, is waiting to see what the experts find.

“The ATF is the world’s leading expert in fire investigation and they are especially sensitive to the loss of life,” Vergon said. “This case could be a case study used to educate firefighters in the future.”

This story was originally published October 26, 2015 at 8:09 PM with the headline "Cause of blaze that killed two KC firefighters slowly emerging as investigation enters third week."