One of several Amtrak train cars that derailed off of an overpass. (Twitter Photo / Pierce County Sheriff)

The derailed train making its inaugural trip from Seattle to Portland Monday was not using a recommended technology system designed to prevent certain types of accidents.

According to reports from Crosscut and NBC News, a system called Positive Train Control (PTC) had been installed on the line that derailed but hadn’t been activated because testing was still underway. The technology prevents train-to-train collisions, derailments due to speeding, and unauthorized train movement by “taking over train operation if the human operator is not responding appropriately,” according to the National Transportation Safety Board (NTSB).

Early indications show that the derailed train was traveling at 80 mph on a 30 mph track, said Bella Dinh-Zarr, a spokesperson for NTSB, during a press conference Monday evening.

NTSB is investigating the cause of the deadly Amtrak derailment, which is still unknown. Speed is one of several factors the agency is looking into. NTSB has been recommending PTC for many years. In 2008, Congress mandated PTC on all major rail lines but implementation has been delayed several times because of how costly the system is.

“PTC would prevent types of accidents such as this,” Dinh-Zarr said during Monday’s press conference. “Whether it would prevent this accident remains to be seen. We should remember that PTC can’t prevent every accident but it does prevent certain types of derailments, over speed accidents, as well as incursions into work zones.”

Amtrak train No. 501 derailed on an overpass in DuPont, Wash. about 50 miles outside of Seattle early Monday morning. All but one of the train’s 12 cars went off of the track, hitting five motor vehicles and two semi-trucks on the freeway below. There were 86 people on the train. Three are confirmed dead and dozens were injured, according to an update from the Washington State Patrol.

It was the first run of a new Amtrak service, designed to make the trip from Seattle to Portland slightly faster and more reliable, bypassing curves and single-lane tunnels that slow trains down.

Watch the video below for updates from NTSB as of Monday evening.

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