re: Mir drills
Aboard Mir they had different drills according to the speed of the loss of pressure. They quickly figured out where it took place and could close the hatch and save the rest of the station.
However, with a ISS that is mostly in length (rather than a cross shape), a leak in the middle module could prevent the crew from getting from one end to another of the station and if the rescue vehicle is on the other side...
Raoul