This is what an exploding propane tank looks like: You can see most of the energy and heat is expended going upward not out, and only lasts for a split second. If you were standing right next to it, you might be burned some but in no way killed unless it was a huge amount of propane.
And this is what the canister looks like, the entry and exit points of my bullet are peeled back, but otherwise the canister is in tact, meaning the explosion created no shrapnel.
BTW, ignore that goofy ass look on my face...