Chapter 19: Diseases of the Eyes, Ears, Nose, and Throat

Due to the difference between the external pressure (4.4 psi) and the cabin pressure (10.9 psi) there is a force of 16,848 pounds holding the door closed. A person would have to exert a force greater than that in order to open the door. ... If you are flying with a cold, sinus infection or allergies, your Eustachian tube could be blocked ... ................
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