Why do people have to fart in the stairwell? You know that stuff lingers. It's got nowhere to go but up and down and you're ten seconds from being outdoors where there's breeze and open air. Is it so bad you can't hold it in for ten seconds? Maybe that's why you were heading outdoors - you felt an emergency fart coming on but you couldn't quite make it. If that were the case, I'm wondering, after your gas explosion, did you turn around and go back to work realzing it was too late? That mission was not accomplished? Or did you continue your way out the door thinking, "I'd hate to be the guy coming up the stairs in the next five minutes."