Eight Massachusetts Bay Transportation Authority vehicles derailed in 2016, the nation’s highest overall figure and the second consecutive year the transit agency has had among the most light-rail derailments in the country, according to federal statistics.

Last year, six Green Line trolleys and two subway maintenance vehicles derailed, according to data from the National Transit Database, which tracks safety data for transportation systems.

The New Orleans Regional Transit Authority and the San Francisco Municipal Railway each had six derailments across their systems, while the Washington Metropolitan Area Transit Authority and the Greater Cleveland Regional Transit Authority each had five.

Safety experts said derailments are worrisome and must be addressed. And while nobody was hurt, delays often result.


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