the reason I ask is because I had a buddy in Washington St who had the most wonderful shop. He restored cars.
40 x 40 with 12 ft ceiling and rafters above that. All steel.
Of course he had to heat it.
He brought in a Honda car with a leaky gas tank which dropped at least 3-4 gallons of unleaded regular on the painted concrete.
Then the electric heater kicked on later that night.
He was not in the the shop.
He made the news that night. Neighbors said they could see the fireball from nearly 3 miles away.
Hope he had insurance!..................