Time for an energy anecdote
Yesterday as I was filling the gas tank on my H260, I thought of this very same explosive subject. I looked over to the adjacent slip to make sure they weren't grilling.
40 years ago as a dumb kid working for the railroad, I had to fill an alcohol heater in the confined end bunker of a refrigerated freight car. Standard procedure was to extinguish the flame before doing so. I had done this procedure many times but this particular time, I didn't extinguish the heater.
The heater flashed in my face, singeing my eyebrows and hair. I can't explain why I wasn't blinded or even burned.
I do know this: If I had been filling a gasoline heater, I would have blown up the whole end of the freight car, including me. At that moment, I learned how little energy there is in alcohol.