The brakes for an escalator at the L'Enfant Metro Station failed Saturday, causing the escalator to speed up and dump people in a pile at the bottom, according to a report from Metro's safety committee.
For 18 seconds, the escalator accelerated until a safety sensor detected it was going too fast and shut it down, The Washington Post reported.
Metro Deputy Chief of Rail Safety Robert Maniuszko said the unit involved, a Westinghouse Modular 100, had been running in the ascending position but the station manager reversed it and turned it to descending due to the crowding.
"There was very heavy loading on the escalators," he said. The escalator motors stopped due to an "overspeed fault," he said. When the escalator shut down the brakes were applied, but they failed.
One brake had oil on it from a leaking motor housing and it showed brake pad wear. It was last serviced in September and overhauled in 2004, The Post reported. It's not due for another overhaul for at least 10 years.
The mishap occurred on the same day the system set a Saturday ridership record -- thanks to the Jon Stewart and Stephen Colbert rallies -- and injured 16 people. Four were hospitalized and one had serious injuries, including possible internal injuries, according to Maniuszko.
The weight of the crowd caused the motors to shut down, according to the preliminary report.
Metro is investigating reports that a similar accident happened Wednesday at the Gallery Place/Chinatown station after the Capitals game, the Associated Press reported.
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