Hell yes they can! They have serval built in safety devices now a days, too make one have a steam explosion would require you to do some engineering work, but they make it that way so as to make them as idiot proof as possible. Go to YouTube and search the "Mythbusters" they did a show on it and made one go through the second story floor then the roof and it continued to go straight up for another 200 feet! A steam explosion is no joke, 1 cup of water turns into 1,500 cups of steam, you have either a 40 or 50 GALLON water heater! Do the math, it is a bomb, but these days you have a better chance of being killed in a plane crash while simultaneously being struck by lightning! :)