Sequence Of Rosedale Collision, Explosion Examined
ROSEDALE, Md. (WJZ)--A dozen National Transportation Safety Board officials are on the scene of the train collision, which led to a huge blast in Rosedale.
Alex DeMetrick has more on the accident sequence and that powerful explosion.
The NTSB will eventually nail down the specifics, but some of the larger elements are coming together.
Why this large trash truck was on the tracks the same time as the CSX freight train focuses on a small crossing a short distance away where the two collided.
Only a small sign marks the crossing.
According to Baltimore County's fire department, the train was heading westbound and the truck was headed north when they met.
Onboard black boxes will give the train's speed and breaking action and a video camera on the engine.
"Should be able to tell us what the train crew saw as the train went down the track," said National Transportation Safety board member Robert Sumwalt.
Those cameras have caught past accidents like this train hit by a tornado.
In real time, it shows how quickly all that moving weight can fly out of control:
Of course the Rosedale crash added an extra force.
"When it exploded it sent a concussion wave that reached us here," said Md. Air National Guard Senior Master Sgt. Sterling Johnson.
And the Maryland Air National Guard's fire unit responded.
It was the first unit to get water onto the fire.
As for the blast, one possible explanation is boiling liquid expanding vapor explosion, or blebe for short.
"A blebe is when one of the containers becomes too heated and it needs to vent and it can't vent, so it explodes. And when a blebe happens, it's going to destroy everything around it," said Johnson.
According to the air guard's fire crews, who specialize in extremely volatile blazes, dust from the plastic pellets that burned might have also triggered an explosion.
The truck driver, a volunteer firefighter, was hurt in the incident. He is in serious condition at Shock Trauma.