Philadelphia’s subways, buses, and trolleys could be shut down on Tuesday if the Southeastern Pennsylvania Transportation Authority (SEPTA) and Transportation Workers Union Local 234 cannot reach an agreement by midnight tonight. The strike could impact approximately 576,000 commuters. The major issues being negotiated are the length of breaks, pensions, and healthcare.
See "SEPTA, union, still talking as possible strike looms", Jason Laughlin, Philadelphia Inquirer, October 31, 2016