Does anyone know anything as to why the TTC has been not complying to the Ontario Building Code (as I read it) for not putting up "non-climbable guards" at Downsview and the Sheppard line since the 1995 Safety Requirements with Stations" Building Code 3.3.1.17?
Also Why would they are not have been installed since they renovated all those yello lines on all 69 stations. When they renovated those yellow line, why wouldn't they have to comply to the building code (the most recent version 1995) which happens to include platform safety?
I would bet since trains are federally regulated, that specific building requirements for train platforms are different.
Set aside that likelyhood however and examine the building code. Remember also that the code is not set in stone, that exceptions are given all the time, and that all you need to do to be in compliance is legally argue that the subway platforms are a loading dock (as they are given a specific exception). This could be a reason why new stations don't need doors. Low floor stations don't need doors under the specific requirements you state anyways, and in theory a low floor station serving the subway train but with stairs up to the doors, would only require guards on the side of the stairs, not as a barrier between people and the track. That last point provides a great legal argument that the requirement doesn't need to apply, as a low floor platform is not more inherently dangerous that a high floor one (besides the accidental falling threat, which you could argue is ameliorated by providing a safe zone under the platform edge).
As for old stations, you are taking a very narrow view of grandfathered. You have to be modifying the specific element for changes to be required. For example, you couldn't build barriers that were too short or climbable. But when you replace tiles, or preform normal maintenance you are not required to bring a building up to code. It would be an undue burden on everyone to make changes across our entire society. There is a reason there are newly renovated office buildings that are not wheel chair accessible and were still approved, even with new elevators and other major interior work. The building code is not some grand doctrinaire.
As you can see in these building code commission decisions, the code is not set in stone.
In this case the commission allowed a climbable guard.
In this case the commmission allowed a low height guard.