A selfie taken shortly after a Southwest Airlines 737 lost cabin pressure can teach us all an important lesson about oxygen masks and what to do in an emergency.

Two weeks ago, Southwest Airlines Flight 1380 suffered a catastrophic loss of its left engine. Debris from blown engine skipped off the left wing, impacted the fuselage, and struck a passenger window causing it to immediately blow out. This resulted in a woman--who did not have her safety belt on--being partially sucked out through the window. She later died of her injuries.

It also resulted in the complete loss of cabin pressure and for oxygen masks to fall from the ceiling. One passenger managed to snap a selfie of the event which tells us quite a few things about what humanity does under extreme pressure. Or lack of pressure, depending on how you look at it.

First is that despite a near-death experience, people will still remember to take a selfie. Second is that people will immediately forget instructions provided to them by aircrew not 20 minutes ago on how to properly wear an oxygen mask.

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Although this Twitter user makes it seem like the people in this photo are simply negligent, the reality is they’re all under extreme emotional stress and can only really remembers things they’ve done countless times before, not something they’ve never done and only been told to do. That’s why each mask has a picture of how to wear it--a picture that also was ignored as people scrambled to simply put their mask on any way they could.

As for why there are oxygen masks at all, it’s not, as Fight Club would have us all believe, to make us as “calm as Hindu cows.” It’s so we don’t suffocate.

There’s barely any oxygen at 38,000 feet (an aircraft’s usual cruising altitude) and it can take several minutes for a plane to safely get down to an altitude where there is oxygen. If you don’t have a temporary source of O2 before the plan gets below 10,000 feet, then you might perish.

But it seems clear that there needs to be some other way to get people to remember how to wear oxygen masks early. Pictures and demonstrations just don’t seem to cut it.

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