Imagine you are sitting at your desk. Fire alarm goes off, and you get a tweet: OMFG WERE ALL GONNA DIE!!!
Then you all die. Awkward having that as your last words.
But seriously, it’s to avoid panic or dangerous info like “George just jumped from the 15th floor!!!” or “Stairwell B is clear” when it may not be true.
http://www.boxcutters.net bbox
Shopped.
It would have originally been “Do not use lifts” [elevators] – always included on emergency instruction forms…