Toronto Transit Commission Improves Subway Safety


At a Glance

  • Client(s)
  • Toronto Transit Commission (TTC)
  • Project Location(s)
  • Toronto, Ontario
LTK-designed railcarAuxiliary wayside system a safe bet. 

The south segment of Toronto’s Yonge-University-Spadina (YUS) line, which opened as Canada’s first subway in 1954, had most of its original signaling system when the TTC decided to upgrade in 2008. LTK, an industry leader in signaling and train control, was retained in an extension-of-staff role to consult on the design of a fixed block auxiliary wayside signal (AWS) system to provide backup in the event the communications-based train control (CBTC) system failed. The wayside system would also allow trains and work cars not equipped with CBTC to operate on the YUS line.

LTK’s work included the following:

  • Verification of safe braking calculations for new block layouts for the Union and Bloor interlockings based on the application of the TTC’s speed control system and fixed-block principles
  • Development of an alternative auxiliary wayside system block layout for the south segment
  • Completion of a block layout design for the Davisville interlocking and verification of safe braking parameters
  • Development, production and verification of block layout designs for the rest of the YUS line based on application of a minimal auxiliary wayside system.

LTK concluded that installing a fixed-block auxiliary wayside signal system to augment and support the CBTC system would improve passenger safety and was financially sound.