Why can they not start/end their shift at the end of the line if they are not the last run of the day?
And have their washroom/coffee/smoke break at the end of the line?
When you say shifts are chunked should they not all be staggered by 3 minutes even if it is at rush hour?
Basically the operator gets off his train and then waits for the second train to start again. Sufficient time for a coffee and a washroom break.
For those that start at the terminal and end at the end of the line you will have to pay then to get back to the starting point (15-20 minutes max). There may be a fairly efficient mode of transportation right nearby to do so!
You may think of it as slave labour but it is not. This is how most private firms operate and the attitude that its slavery is similar to the entitlement beliefs that many civil servants have.
As someone is an employer, an investor, has never worked for government, nor been paid overtime, nor been a member of a union, I can assure I have no time for 'entitlement' where by that we mean a love of arbitrary or capricious rules, or an overly officious sense of how things should be done.
However, I do believe in reasonable working conditions. I would never pay someone less than $20 per hour to do anything, I don't believe anyone should have less than 3 weeks vacation in a year, I don't think anyone should have to work 12 hour days, or go without reasonable meal or washroom breaks.
That you seem to feel these things are ok, is not in any way reasonable to me.
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Yes, washroom breaks can and should be addressed through stand-back crew changes (which is what you described in terms of having another crew ready to go). The TTC already does this in some situations. There is still a time lapse. On trains, last I saw, you still had a key in to activate the cab, the operator likely has a jacket and maybe a bag hanging behind their seat. They have to stop the train, turn the key, grab their stuff, open their door, get out of the seat, next operator has to take their jacket off, hang their bag up, close the door, take a seat, insert key. You won't drop this to under 60s no matter how diligent the crew. In the case of trains with a guard, the doors also require a key, but the guard will likely put their stuff in a cab prior to taking up their spot at a window in the 4th car.
If you think TTC staff have it so easy, read up.
https://www.reddit.com/r/toronto/comments/4nxlfd/iama_former_ttc_operator_ama_long_text/
May I add, your lack of empathy for workers if your own form of entitlement.
A rather off-putting one at that.