Exploding Tire that Killed Los Angeles County Firefighter was 'Rare'

No one knew the burning construction vehicle could become a bomb.

Not the driver who tried to douse it with an extinguisher. Not the workers who sent water gushing onto the engine. And not Andrew Pontious, an L.A. County firefighter dispatched to the Palmdale quarry on June 14.

Pontious had sprayed water near the vehicle for about two minutes when one of its nearly 7-foot tires exploded, according to a Fire Department analysis completed this month.

Hunks of rubber and steel shot the length of a football field. Pontious, 53, died instantly.

"It was like an IED," David Pontious, Andrew's brother who worked at the same Palmdale fire station before retiring this spring, said, referring to an improvised explosive device, as a roadside bomb in a war zone is known.

It's common for tires to blow out in a fire, with pressure building until the air whooshes out with a loud pop.

But, sometimes, the tire doesn't blow — it explodes. The air inside the tire combines with the heat, starting a chemical reaction powerful enough to create a violent shock wave. The larger the tire, the bigger the blast.

"It's shrapnel. It's just like a bomb. It's the same principle," said Olivier Bellavigna-Ladoux, a mechanical engineer who specializes in vehicle safety.

In the niche world of vehicle safety engineers, it was a known risk — rare but lethal. To firefighters across California, the threat was essentially unheard of until highlighted by Pontious' death.

This month, L.A. County fire officials issued a safety notice instructing firefighters to keep a distance from burning heavy-equipment vehicles. Fire departments in the city of Los Angeles, Orange County and San Bernardino County, as well as the California Department of Forestry and Fire Protection, sent the notice to their members, who, combined, include thousands of California firefighters.

"There was no knowledge that these kinds of big tires could blow in such a way that could kill someone," said David Pontious, 55. "It was just a freak accident."

Rescuing people from burning buildings was perhaps the least notable thing about Andrew Pontious.

He was, first and foremost, an outdoorsman.

As a teen, he disappeared for entire weekends, telling his family he planned to "melt into the mountains." He loved to hunt and cook, sometimes combining the two passions at the fire station by serving quail enchiladas, the poultry fresh from a recent hunt. In his spare time, he was a caretaker at a refuge for bighorn sheep, traipsing into the woods in the middle of the night to check on the water supply.

Pontious had resisted becoming a firefighter like his older brother. But in his early 30s, his job helping a lumber company avoid trees with spotted owls started to feel like a dead end.

He fought fires out of Rosemead and El Monte for about a decade before his brother convinced him to come to Palmdale. Fire Station 93 was inconveniently located, about 70 miles from the Upland home he shared with his wife, Kim, and his stepdaughter, along with their hunting dog, four cats and a desert tortoise. But the station was known for the intensity of its calls — grassland fires, stabbings, a cat stuck in a tree that turned out to be a mountain lion.

For nine years, the brothers worked together, David as the captain and Andrew the perennial firefighter, never interested in moving up the ranks.

Andrew just wanted to fight fires until his planned retirement next year. And he was usually the first to arrive.

Pontious and his crew pulled up to the quarry at 2:06 p.m.

Four minutes earlier, one of the construction vehicle's rear tires had exploded, cracking the windshield of a nearby truck and sending quarry workers rushing back.

In the chaos, nobody told the firefighters at the scene about that first tire explosion, said Dave Gillotte, head of the L.A. County firefighters union. And nobody told them the vehicle had been burning since at least 1:38 p.m.

"If the knowledge of the tire exploding and how long it had been burning were accurate and up-front, I know that our firefighters would have absolutely altered [the response]," said Gillotte, who interviewed the firefighters at the quarry that day.

The longer a tire is exposed to heat, the more likely an explosion becomes, said Bellavigna-Ladoux, the mechanical engineer.

This was science that the fire department only learned in the aftermath.

"I never was taught that there was a shock wave that comes out of a tire explosion," said L.A. County Fire Chief Anthony Marrone. "Had I been the firefighter on Engine 93 that afternoon, I truly believe I would have been doing the same thing that firefighter Pontious was doing — and I would have been killed."

The fire department analysis of the incident noted that officials could find "very little information" on the effect of fire on large tires.

The safety notice the department issued after Pontious' death instructs firefighters never to get within 15 feet of a burning heavy equipment vehicle — and to come within 50 feet only to rescue someone. The department gave similar guidance for tractor and trailer fires.

Patricia Dolez, a scientist whose study on tire explosions is cited in the L.A. County safety notice, said few workers who operate large vehicles — namely miners and truck drivers — are aware of the risk. The Palmdale driver's first reaction was to try to extinguish the fire, she noted, even as the sparks spread.

Dolez said her study was commissioned nearly two decades ago by a Quebec research institute after several truck drivers were killed by exploding tires. Following Pontious' death, the U.S. Mine Safety and Health Administration advised that if a vehicle starts smoking, miners should retreat and wait for emergency responders.

It's less clear what those responders are supposed to do, said Stephen Gilman, a vice president with the International Association of Fire Fighters.

Gilman said the association, which represents 345,000 firefighters and first responders nationwide, is hoping for some national guidance for the people who will run toward the fire.

Miners are "not going to be putting out their own fires," Gilman said. "That leaves the only option of calling 911."

This story originally appeared in Los Angeles Times.