Pressurizing the cabin of an airliner overcomes the fact that the density of the oxgen in air and the temperature decreases with altitude. So that the pilots, airline staff and passengers can travel in optimum conditions, pressurizing the cabin is therefore necessary when flying above a certain altitude. But at what altitude?
It is in fact an international standard. Passengers interviewed at an airport give us their opinion on the matter. You will find the answer at the end of the video. Finally, did you know that the air we breathe is composed of 78% nitrogen and 21% oxygen?