Many years ago I was in HAZMAT Incident Commander training and instructor discussed the perils of gasoline vapors. Duh. However, he discussed a Mutual Aid drill of several FD's and old house to burn down for training. The plan was to burn it down in sections to simulate different types of fires. So the FD Chief in charge of drill asked a firefighter to put some gasoline (turns out way too much) down through basement window to simulate furnace fire. However, several questions on protocols and quite a bit of time had gone by. This was a small cottage type house so not really big floor plan. So after lengthy clarifications, the order was given to turn on cameras for training and to begin furnace "attack". So firefighter walks over to basement window, opens, lights road flare and throws it in.
Ah Houston, we seem to have a problem!! Whole house lifted off foundation in huge Whoosh and giant fireball into sky! Nothing but kindling left inside foundation on blazing fire!
He claimed there was zero talk for few seconds then nothing but expletives! Then laughter that was hilarious.!
So his point to us was never underestimate a gasoline spill. No kidding...