If you've ever flown in an aeroplane, you've heard the spiel about the oxygen mask. If you looked up from your phone, you've even seen a flight attendant demonstrate exactly how to put it on. And yet, people on the recent Southwest flight still got it wrong.
Photo: AP Photo/Matt Dunham
PEOPLE: Listen to your flight attendants! ALMOST EVERYONE in this photo from @SouthwestAir #SWA1380 today is wearing their mask WRONG. Put down the phone, stop with the selfies.. and LISTEN. **Cover your NOSE & MOUTH. #crewlife #psa #listen #travel #news #wn1380 pic.twitter.com/4b14lZulGm
— Bobby Laurie (@BobbyLaurie) April 17, 2018
The mask is a tiny, round cup, and it may not be obvious in the moment exactly how to wear it. But the oxygen mask works best if you can get it over your mouth and nose, and tighten it so there's as little space as possible for oxygen to leak out. If you need help remembering how to wear it, there is literally a picture right on the bag.
The masks are necessary when the cabin loses pressure at a high altitude. Air is thin enough at commercial airlines' cruising altitudes that we couldn't stay conscious if that were all we had to breathe. So on every flight, the cabin is pressurised, basically stuffing extra air into the aeroplane so we can breathe normally.
But if a hole gets blown in the plane, or if there's a problem with the pressurisation system, the masks will drop from their little compartments.
The masks only provide enough oxygen for 15 minutes or so. That should be enough time for the pilot to get the aeroplane down to a low enough altitude that they aren't necessary.
Here's the meaning behind those other oxygen mask facts you've heard a hundred times:
- "Tug on the mask to start the oxygen flowing" - Tugging pulls a pin in the oxygen generator that causes it to mix certain chemicals together. Oxygen is one of the by-products of this reaction, and it flows into the bag and tube.
- "The bag may not inflate" - Oxygen is continuously produced by the chemicals in the generator, so if you're not taking a breath, the bag will contain the oxygen until you do. When this happens, it can inflate. But if you're breathing or if your mask is leaky, the oxygen will leave the bag before it has a chance to fill up. Either way, the oxygen is still flowing, and you should keep using the mask. For the best results, try to get a tight seal.
- "Secure your own mask before helping others" - Depending on the plane's altitude, people will only have a few seconds to minutes of "useful consciousness" without supplemental oxygen. You don't want to spend that time wrestling with a toddler while becoming oxygen-deprived yourself.