For this question, why is it necessary to exhale when going up? Isn't the pressure outside of the person decreasing since the person is going up? If the pressure is decreasing, why would it cause a rupture?
The mechanics of breathing follow Boyle's Law which states that pressure and volume have an inverse relationship.
The process of inhalation occurs due to an increase in the lung volume (diaphragm contraction and chest wall expansion) which results in a decrease in lung pressure in comparison to the atmosphere; thus, air rushes in the airway.
The process of exhalation occurs due to an elastic recoil of the lung tissue which causes a decrease in volume, resulting in increased pressure in comparison to the atmosphere; thus, air rushes out of the airway.
"Overexpansion injuries are caused by holding your breath during ascent. If you’ll recall Boyle’s Law, volume varies inversely with pressure. That means if you take a breath while diving on scuba then ascend, the air in your lungs will expand as the pressure on your body from the water decreases. If you hold your breath, this expanding air has nowhere to go, so it ruptures the alveoli of the lungs..."
This site uses cookies to help personalize content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies and terms of service.
