When a leaked gas reaches the right stoichiometric ratio, it turns into a fuel-air explosive (FAE), essentially a small thermobaric bomb.  Aeresolize the gas/CNG/Propane and it becomes 100X the explosive value. https://www.ar15.com/forums/general/1_gal_of_gas___10_sticks_of_dynamite/5-1346634/ FAEs banned by Geneva Convention