Two Los Angeles firefighters remained hospitalized in critical condition Friday after they were injured in a compressed natural gas truck explosion in Wilmington.
One of the firefighters, a 37-year-old, 9-year LAFD veteran, was airlifted to a burn center for specialty care, LAFD Capt. Erik Scott said Friday. The other hospitalized firefighter was in critical, but stable condition Friday morning.
The other seven were released from the hospital. Their injuries include burns, injuries from flying shrapnel and what the LAFD described as effects to their hearing.
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They were putting out the compressed natural gas truck fire Thursday morning in the 1100 block of North Alameda Street when one of the vehicle's two 100-gallon CNG fuel tanks pressurized to at least 3,000 psi exploded.
"Crews applied water to the flames and nearly completed extinguishment, when catastrophe struck," Scott said. "One of the tanks exploded violently, immediately injuring nine LAFD firefighters. Crews quickly declared a "Mayday" on the radio for "firefighters down." Some of the nearby firefighters were thrown dozens of feet from their location and knocked out temporarily. Some of the less-injured crew members scrambled to help the more severely injured."
Remnants of the fuel tank were found hundreds of from the truck, a big rig cab without a trailer. Security camera video of the explosion showed a giant fireball rising above the South Bay community.
"The unique aspect of this vehicle is that it's not run on diesel or gasoline, but it is actually propelled with CNG, or compressed natural gas," Scott said Thursday. "The explosion was significant. The ball of flame was as high as these telephone poles."
The truck driver was not injured. The driver called 911 after noticing something wrong with the truck, firefighters said.
In a statement Friday, the trucking company said is is working with authorities to determine what happened.
"HLT is aware of the explosion of one of our compressed natural gas (CNG) trucks in Wilmington, California on the morning of Thursday, February 15," the company said. "We and our advisors are currently investigating the incident and are working with authorities to determine the cause. We are grateful to the firefighters who responded to the scene and our thoughts are with those who were injured in the course of ensuring others' safety."
Compressed natural gas (CNG) is a fuel gas composed mainly of methane that is stored in hard pressurized containers.
CNG vehicles have spark-ignited internal combustion engines, much like gasoline-powered vehicles. The CNG that powers the vehicle is stored in a cylinder that supplies fuel to fuel lines, which have a pressure regulator. The CNG eventually enters a combustion chamber, where it mixes with air and is compressed and ignited by a spark plug.
