News releases

Automated Positive Train Control system increases Sounder riders’ safety

Investments will help continue two-decade track record of no rider injuries or unavoidable incidents

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Sound Transit briefed media today on its completed implementation and certification of Positive Train Control (PTC) on all Sounder commuter rail vehicles that run between Lakewood and Everett. Positive train control technology can control train movements under certain conditions, automatically applying brakes and avoiding collisions. 

“Safety is our most important priority at Sound Transit,” said CEO Peter Rogoff. “Each and every one of our riders must get home or to work safely every time. Adding Positive Train Control on all our Sounder trains will help us maintain our impeccable track record.”

Under the Positive Train Control system, should an engineer exceed the permitted speed or fail to brake on approach to a work zone or a signal, PTC will automatically apply the brakes and stop the train.

There are three categories of PTC equipment: Wayside equipment which is installed on the track; onboard equipment which is installed on the train; and back office equipment which is installed in the train operations center. Once the system is operational wayside radio and global positioning systems (GPS) determine train location and ensures trains are operating within established parameters. 

Sound Transit implemented PTC in close collaboration with Burlington Northern Santa Fe (BNSF), an industry leader in PTC and the operator of Sounder service under contract to Sound Transit. PTC equipment on trains and tracks must communicate seamlessly and routinely with the back office systems deployed by BNSF. Sound Transit PTC equipment is fully interoperable with BNSF systems. Sound Transit executed its contract for installing PTC equipment in 2013, well ahead of many passenger rail agencies, and completed the installation and commissioning last year well in advance of the federal government’s deadline.

Sounder trains from Everett to Seattle began testing PTC in June 2017. Sounder trains from Tacoma to Seattle began testing PTC in August 2017. Sounder also operates on tracks owned by the agency between Tacoma and Lakewood known as the Lakewood Subdivision. Sounder service is also certified to operate under PTC in this subdivision. 

BNSF has a two minute video that explains how PTC works

Sounder b-roll can be found here

Sounder trains currently serve more than 17,000 riders each weekday, with the region’s rising congestion expected to continue pushing demand higher. In 2016 voters approved significant investments in expanding Sounder South service, including longer trains and platforms to increase system capacity by more than 40 percent. Future investments will extend service further south to Tillicum and DuPont and improve stations. Other potential investments include schedule and service improvements and projects to make stations more accessible.