I am trying to figure out what kind of force would be given off if a 4000 gallon tank of ethanol were to ignite. My husband is a distiller, and to help raise awareness of safety issues, he's trying to explain to his coworkers the kind of explosive force that could occur if it were to ignite by faulty wiring, lightning strike, or some dummy smoking around it. All I can understand is that 1kg of ethanol contains 27,000 joules, which can lift a pound 9 inches. Beyond that, I have no idea what I'm doing here. If I had 4000 gallons of ethanol ignite in a tank, about how many square feet would it destroy? This would be a safety concern for even neighboring buildings, not just employees, correct?