Do you know why aircraft need to be pressurized?

Pressurized means maintains a constant pressure even aircraft flying in high altitude.

Aircraft cabin has to be pressurized simply because at the high altitude (up to 40'000 ft), the air pressure is too low for people to be able to breath. Thus, pressurization is needed to enable passengers and crew to breathe normally.

Low air pressure during air travel also decreases the amount of oxygen in the air. If the blood has an inadequate supply of oxygen for the requirements of the tissues, this is called hypoxia. Hypoxia can cause personality changes, decision making more difficult, basic senses dulled, dizziness, unconsciousness and death will follow if oxygen lack continues.

Here is briefly how aircraft obtain its oxygen for it passenger during its long flight.

Let's watch the risk of flying without air pressurization-  No Oxygen Disaster.

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