Oxygen is one of the key ingredients for fire. So how do we get emergency oxygen masks on airplanes without potentially turning the entire plane into a giant fireball; trick is that oxygen masks aren't holding oxygen. Instead, they are connected to chemical oxygen generators, which have the ingredients to make oxygen on demand. It's not there. But we can make it to get the generators going. You need some kind of trigger. And you know what the trigger is. It's highlighted in every safety demo to start the oxygen flow, pull the mask towards you. It's that tug that releases the safety pin of the generator, creating a spark that kick-starts the chemical reaction that forms the oxygen. The heat from that spark quickly decomposes sodium chloride inside the generator into oxygen and table salt, and other minor by-products the sodium chlorate isn't bottomless, so these generators don't generally provide oxygen for more than 30 minutes that's okay though; because you don't need it to last forever, just long enough to get down to where there's more oxygen and long enough to land.