Recently a small one-story house (in a community near where I live) was scattered over a half mile area from a natural gas explostion. BIG boom and nothing was left standing.
Ten years ago a natural-gas storage facility began leaking in the wee hours of the morning, about thirty miles from here. About 7 a.m. a car finally came by that ignited the mist that had settled over everything. The car was crushed and its occupants killed instantly, and my 12-story office building 30 miles away swayed back and forth a couple of feet when the shockwave finally arrived, two and a half minutes later......early arrival in the office next to mine said he could hear my office chair rolling back and forth and bumping into things. The boss, coming up the elevator, got bounced back and forth in the elevator shaft -- he thought the elevator was about to drop, scared him silly. Don't underestimate the power of an air-fuel explosion: after fusion and fission, it's the third most powerful we know about.