TriMet and the Oregon Department of Transportation believe the door on a speeding MAX train was left open because of a corroded switch.
TriMet met says it is moving to inspect and repair all similar switches on MAX trains as a result of the ODOT safety investigation.
The incident happened along the Banfiled MAX line on Feb. 15. It was recorded on a passenger's cell phone and posted on YouTube, where it was picked up by the local media.
According to a statement issued by TriMet on Friday, "TriMet safety specialists believe they have identified what led to the Feb. 15, 2013 incident, in which a MAX door was open while the train was moving. Safety specialists and mechanics have spent countless hours scrutinizing the train but could not replicate the failure. However, they did find excessive corrosion on a switch inside the doors bridgeplate, or ramp, mechanism. After ruling out all other possible causes, TriMet believes this led to the incident and changes to help prevent this in the future are now being made to all vehicles with the same ramp systems. "
The statement says the incident began as the train was preparing to depart from the Hollywood/42nd Avenue Transit Center.
"As the train was preparing to leave, a person attempted to stop one of the last doors on the second or following car of the train from closing. When the person made contact with the sensitive edge of the door, the door opened back up, which is how it is supposed to function. The failure happened when the train was able to move while the door remained open," the statement says.
ODOT investigated the incident because it is designated by the federal government to assure safety on the light rail system.
According to the statement, a passenger alerted the driver to the problem as it was happening. The driver did not respond and has been disciplined.
"A rider did initiate a call to the MAX operator through the emergency intercom soon after the train pulled away from the Hollywood Transit Center with the door open. The operator did not activate the intercom and has been disciplined. As this is a personnel matter, no additional information is available," the statement says.
Amalgamated Transit Union 757, the union representing most TriMet employees, has said the incident is a sign that other MAX trains have serious safety issues. The ODOT inspection did not find any. In the statement, TriMet accused the union of making the charge to distract public attention from the stalled negotiations over the next labor contract.
"While TriMet appreciates the ATUs commitment to safety, the agency wants union leadership to stop these diversionary accusations to delay negotiations on a new contract. TriMet faces a future of service cuts and fare increases if the agency does not win the unions challenge to the arbitration award last year and prevail in making reforms in the upcoming contract. Current contract negotiations are at a standstill as the ATU has refused to come to the bargaining table," the statement says.