I've been using that requirement for a long time to beat up on Architects who want to give me only 1 door...and make it swing into the room. I'm not sure when it went into the NEC, but it's been a part of Chicago Code since before 2000. Since "panic hardware" is designed to work on door that swing "in the direction of egress", I've been happily designing safer rooms for the good of all of us who work for a living.
