IamA Railway Conductor, Engineer, Yardman and Switchman. I make you late for work on purpose. AMA!
My short bio: I'm based in Western Canada and I worked for Class 1 railways (the big ones) as well as a couple short lines. I'm currently a humble yard switchman and have a couple hours to kill. AMA!
If you have super specific questions I'll do my best to quote federal rules. We have specific guidelines (unknown to most) that we must follow, so, I'll backup everything I say with sources when asked. :)
My Proof: http://imgur.com/vgi5p0F
edit 1: had a nap there, this kinda got out of hand...i'll see how many i can answer, but i'm here for a while! edit 2: thanks for the gold, kind stranger!