Oh my god.. I don't know if that's real or not, but that's gotta hurt hitting the back wall like that... But that's still hilarious haha.
i truly want to know if that is real, but it sure as well was funny. edit: i guess it is, they actually tested the damn things on themselves before doing it to this idiot, btw that sign on the door actually says "WARNING: YOU ARE ABOUT TO BLOWN ACROSS THE ROOM BY A PNEUMATIC CANNON" http://www.zug.com/live/86516/The-Pneumatic-Cannon-Prank.html
Yeah, definitely not real, but there is a longer version out there somewhere that shows a "backstory" to it.
Yeah that amount of force needed to apply a knock back like that would cause severe internal hemorrhaging and a slow death Good thing its fake lol.