Can’t think of anything really specific, I’d probably ask what happens and what they do when it all goes horribly wrong as well as any general horror stories they have it’ll give you a good idea how to relate of your own experiences for the interview.
I know they’re quite concerned about under-load at the moment so it might be worth asking if there’s any sort mental checklist they follow or movements/ actions they do. (Look up point and call from Japanese railways) Might be different up there so maybe ask if there’s anything that stood out to them on their last safety brief.
You’ll get the idea of the usual routine just by doing the shadowing and who ever you’re with will probably go over the rules you’ll need to know but you’ll get that from training school anyway. Security stuff could be useful so ask about HOT and WHAT protocols.
Sorry I can’t think of too much specific but there isn’t that much to the actual job, it’s mainly about knowing the rules and what to do when it goes belly up. Hope this at least somewhat helpful anyway.
What's the best volume to say: "STAND CLEARRRRRRRRRRRR!!!"
Maximum, and repeat until the message gets through.