VIDEO: the TTC teaches you more than you really need to know about subway signalling

For most commuters, the fact that the TTC’s subway trains don’t collide with one another is good enough—no additional explanations are required. Recently, though, the TTC has been shutting down portions of the Yonge-University-Spadina line on weekends so workers can upgrade the signalling systems responsible for the daily no-deaths-or-maimings miracle, leading to some curiosity about the system’s workings. The video above, released yesterday on the TTC’s YouTube channel, goes into quite a bit of detail about how signals prevent trains from crashing into one another, why the signalling systems need to be upgraded and why it’s necessary to shut down subway tunnels to perform those upgrades. Yes, it’s propaganda, but snappy animations and an informative voiceover make it edutainment of the highest order. Enjoy.