This is good. I have definitely had some experiences where I wish I thought of this. Rushing through a service while in a state of paranoia and trying to listen to every creak and sound while trying to be ready to bolt at a moments notice is not worth it.
I have turned around immediately at the door once though and just got out of the area as fast possible, that was because just as the door was opening I saw the silhouette of someone else inside move into another room.