Flight safety: What happens if your oxygen mask doesn't inflate?
Many people experience anxiety when flying. At the start of the flight, flight attendants conduct a safety briefing, which includes instructions on how to use oxygen masks.
However, a considerable number of passengers are still unsure about how to properly use these masks. This is largely because, fortunately, they have never had to use them in real-life emergencies. Nonetheless, having a basic understanding of oxygen masks can be immensely beneficial and may even save lives in critical situations. travelandleisure.com discusses this topic.
This need for understanding became particularly evident in 2018 during a tragic incident on a Southwest Airlines flight, where the aircraft's fuselage was damaged, resulting in the death of one passenger. In response to the sudden change in cabin air pressure, the plane's oxygen masks were automatically deployed.
As noted in the pre-flight safety demonstration, passengers often notice that there is a bag attached to these masks, but it may not actually inflate. Fortunately, this does not indicate that the mask is defective, although it can cause unnecessary anxiety for the passenger if not informed.
Firstly, if you're not very familiar with the purpose of oxygen masks on airplanes, you may have wondered why they're needed at all. After all, there's air on the ground, air in the plane, and air outside the plane, so wouldn't you be able to breathe regardless? Technically, no. Airplanes often fly at altitudes above 36,000 feet, which is high enough for the air to be particularly thin, but not so thin that internal combustion engines cannot operate. This altitude is too high for people to get enough oxygen, so the air in the cabin is at a pressure similar to the air pressure found at 6,000 to 8,000 feet. Of course, if the cabin pressure were to drop, the lack of oxygen would likely cause nausea, headaches, confusion, or even fainting, which can lead to death.
Oxygen masks are deployed to help passengers breathe, at least until the plane reaches an altitude from which it is safe to remove them. Oxygen on board usually lasts only 15 minutes.
The creation of "Oxygen"
Even though the demonstrations call it "oxygen," it would actually be very difficult for an airplane to carry a bunch of oxygen tanks on board in the event of an emergency. Instead, the oxygen released into the masks is created using certain chemicals, including barium peroxide, sodium chlorate, and potassium chlorate. These chemicals are stored in panels above each row of seats and are mixed together when the oxygen masks are deployed, a process otherwise known as "combustion." Even though it is generated by chemicals, you are still breathing real oxygen because it is formed as a byproduct of this chemical combination.
The bag can inflate, but sometimes it doesn't because of the way you breathe. The oxygen masks you find on airplanes are called continuous flow masks. This means that the oxygen flows continuously, whether you are inhaling or not.
Because there is a constant flow of breathable air, the bag actually inflates and stores excess oxygen as you exhale. These masks have a one-way flow, so the air you exhale ideally goes out through the valve rather than back into the tube.
If you breathe very fast or very deeply, the bag won't have a chance to inflate with excess oxygen before you breathe in again, so it deflates. Don't worry if your seatmate has an inflated bag and you don't. Both of your masks are working exactly as they should.
How to use the mask correctly
Once the masks are down and you pull yours closer to you, place the elastic band around your head to secure the mask (the yellow part) to your face. Don't forget to cover your nose and mouth. The elastic can be stretched tighter by pulling on the ends attached to the mask itself. This should create a good seal around your face to keep oxygen from escaping.
When the mask fits snugly around your face, you can breathe normally, preferably through your nose, and try to remain calm.
