" My brother likes to fill a leaf bag with 50% oxygen and 50% acetelyne, tie it off, and throw a firecracker on it. "Static can set these bags off while they're filling . . . It happened to some kids I knew in high school and blew up the basement of a nice house, rearranging kids, walls, furnishings, tools, and foundation walls.
The Oxy-Acetylene trick is much safer with a 5-Gal METAL can with sparkplug. Use magneto to ignite from a LONG WAY away and below the horizon of the can.