Amtrak, meanwhile, has completed installation of PTC on all 898 route miles that it owns or controls, including the track from Schenectady to Poughkeepsie. Metro-North has completed installation on its track from Poughkeepsie south, including a stretch used by Amtrak trains from upstate New York.

West of Schenectady, the tracks used by Empire Corridor trains are owned by CSX Transportation, while Canadian Pacific Railway owns the tracks north of the Capital Region over which Amtrak’s Ethan Allen and Adirondack services operate.

The positive train control system consists of signal hardware along the track, Global Positioning System and other technology to accurately pinpoint locations of trains and measure their speeds, and onboard equipment in locomotives or cab control cars that can automatically slow or stop a train traveling too fast or on a collision course with another train.

Dedicated radio spectrum is intended to ensure that all the components work together.

The U.S. Department of Transportation has provided $3.4 billion in grants and loans to assist railroad operators in paying for the safety system.

The system likely could have prevented the December 2013 derailment of a Metro-North commuter train the occurred when the train entered a curve at excessive speed. The crash killed four people.

It also might have prevented crashes in Washington state that killed three and along the Northeast Corridor outside Philadelphia that killed eight.

Congress passed the Rail Safety Improvment Act in October 2008, requiring railroads to have positive train control installed by the end of 2015. It followed a deadly commuter train collision with an oncoming freight train that killed 25 people in Chatsworth, Calif.,  the previous month.

The deadline for implementation was extended at least twice, first to the end of 2018 and then to Dec. 31, 2020, a deadline the freight rail industry said it expects to meet.