Metro investigators said Wednesday that they do not yet know the root cause of the fire that led to the evacuation of the Silver Spring Metro station Tuesday evening, but that they have ruled out the track conditions and are focusing instead on the Red Line rail car involved.
Metro said it reported the fire under the rail car shortly after 6 p.m. Smoke billowed over downtown Silver Spring, but no one was injured, and firefighters brought it under control quickly.
According to Metro, the rail car is a 1000-series car that is the oldest type in the fleet and scheduled for retirement with the arrival of the new 7000-series rail cars next year.
Investigators "are looking at the way the electrical arc-flashing occurred beneath the car, which suggests possible unintended contact between a metal-shielded hose under the train, and power cables," creating an electrical short, Metro said in a news release on its website.
The electrical arc-flashing underneath the car stopped once Metro's Rail Operations Control Center cut off third rail power to the track where the rail car sat, Metro said.
The fire did not reach into the passenger compartment of the rail car, and there were no passengers on board at the time. The passengers had been offloaded at Takoma Metro station.
Metro suspended service through Silver Spring, using shuttle buses to transport passengers between Forest Glen and Takoma Metro stations, then running trains between those stations using a single track beginning shortly before 7:30 p.m. The Silver Spring station reopened for exit only shortly after 8 p.m., Metro said. Full service was restored shortly after 9 p.m.
Metro anticipates that careful examination of the rail car will take several days.