My employer sent me to steam school (one day seminar) at a steam controls company. Man, that was an eye opener.... especially the video of a guy in a manhole when a steam pipe burst. 1600:1 expansion ratio when it's let loose! Guy got popped out of the manhole like a cork. He survived and walked away!
Here's the video. You can hear the steam hammer going on and the guys talking about how you couldn't pay them enough to be in that vault. Some guy says to the guy in the hole "Maybe you should set out for a minute." Guy comes half way out and BOOM! WARNING: Strong Language (no $%@#!!!).