A dramatic example was an October, 1989 New York City steam expansion joint explosion which killed 3 persons, seriously injured 2 others, and caused tens of millions in property damage, clean up, and relocation costs. The cause of this catastrophe was failure to blow down a steam main. This was due to an inoperative blowdown valve which tragically had not been properly maintained. Numerous other steam explosions have occurred since.
Two recent ones occurred in 2007. One was at an electric power plant in Boston where two men were killed. The other was in Manhattan where another persons was killed and atlest 35 persons were injured. This latter accident was captured on You Tube. Notice the fantastic steam geyser from many blocks away. The bottom line is that steam is extremely powerful and it can kill or maim maintenance personnel who have not been properly trained and are not properly focused! Steam explosions can kill you!