Pardon me for veering slighly off topic but I thought some of you may enjoy this.
Back in 1968 I worked in the Chrysler test and development labs in Highland Park Michigan. One of the projects we worked on were air bags. At the time it was just a project to determine if they were even feasible. The state of the art systems of the day utilized a compressed gas in a bottle with a diaphragm seal and electromechanical system to rupture the diaphragm and allow the gas to escape into the bag when an impact was sensed. Chrysler engineers sought to develop something cheaper and easier to build and decided on generating the gas for bag inflations by rapidly burning a fuel. Without getting into the weeds suffice it to say that gunpowder became the initial fuel of choice. Because smokeless generates so much more gas for a given volume than BP and is very sensitive to pressure, it did not take but a few 'booms' to determine BP was a better choice. The earliest "gas generators" we made were filled with BP collected by cutting shotgun shells open, and ignited by using flash bulbs with the glass bulbs removed as detonators that ignited the powder with battery current sent by the impact sensor. I am sure you can imagine the smoke we made when the bag broke, which was quite frequently.
As time went on more sophisticated fuels were developed by outside chemical vendors and (I believe) today all air bags in modern cars use a gas generator that burns a fuel and fills the bag with the gas produced in only a few milliseconds after impact. Think about that when you get behind the wheel next time. The exact same stuff we like to burn in our pistols and rifles was instrumental in developing the air bag in front of you.
"Peace is that brief glorious moment in history when everybody stands around reloading" - Thomas Jefferson