Allow me to explain. You know the part in the flight safety announcement where you’re instructed to put your oxygen mask on first, before helping others? It’s there for a reason.
The researchers at Smarter Every Day put that instruction to the test at NASA, where the experience of being in a depressurized airplane cabin was replicated. If you don’t put your oxygen mask on right away, your body’s oxygen saturation levels drop. You lose the ability to recognize faces and shapes, follow directions, or even save yourself. It’s very scary.
Losing oxygen can trigger hypoxia, rendering you useless in an emergency. You may have the impulse to help others first, but doing so will put you in harm. Take care of your mask first, then help others.