Sound Transit is running Positive Train Control (PTC) on all Sounder commuter rail vehicles that run between Lakewood and Everett.
 
The transit agency held a press briefing on 28 Jan 2019 to provide an update to the technology's use.
 
"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."
 
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.
 
Sound Transit said PTC implementation was completed in October 2018.
 
Sound Transit implemented PTC in close collaboration with BNSF Railway, a major freight railroad, 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 notes that its PTC equipment is fully interoperable with BNSF systems.
 
Interoperability has been a major challenge of the technology for both freight and passenger railroads.
 
Sounder trains currently serve more than 17,000 riders each weekday, with the region's rising congestion expected to continue pushing demand higher.
 
In a tweet following the media briefing, Rogoff said, "With a history of no avoidable major accidents or fatalities, Sound Transit has an outstanding train safety record. Now with Positive Train Control in place on 99 percent of Sounder Trains, we'll make a safe railroad even safer for our 17,000 plus daily Sounder riders."
 
Sound Transit says it 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 statutory deadline.
 
Mischa Wanek-Libman.