There is an ongoing situation involving railroads, the Federal Railroad Administration (or FRA), and the government right now. A new signaling system called Positive Train Control, or PTC, had been introduced by a law passed in 2008, the U.S. Rail Safety Improvement Act. The deadline for having PTC installed was December 31, 2015. Around this time, there was much concern that railroads would have to shut down transport of Hazardous By Inhalation chemicals and passenger traffic. Some railroads interpreted the law as making them shut down all traffic. If this happened, it would have been devastating for the economy. Fortunately, the deadline was extended to December 31, 2018. However, most railroads expect to be fully compliant by around 2020, so there’s nothing preventing more extensions.
PTC involves several components, which would all work together to provide additional operating safety. Speed display/control equipment is on the locomotive, along with a system to inform the control equipment about track and signal conditions. It can include GPS equipment so the speed control unit can know where the engine is and what the speed limit is for that area, and/or equipment to assist with signaling. Also, radio receiving and transmission equipment is needed near the rails to communicate with the GPS system, and can then make moving blocks. Current signal equipment works by making the rails part of a circuit, and then the train closes the circuit, which allows the signals to turn on or change their aspect. The system that Amtrak didn’t have installed on the track where Northeast Regional 188 derailed, ACSES or Advanced Civil Speed Enforcement System, is similar to PTC.
Most big railroads are currently working to install PTC. However, SEPTA is one of the few railroads to have it fully installed, along with Amtrak’s Northeast Corridor which was updated from the ACSES system to PTC and filled in the gaps in coverage on the Northeast Corridor.