Talk:Submarine Escape Immersion Equipment

Decompression sickness
Nothing in is really said in the article as to whether the SEIE protects against decompression sickness(the bends). Does anyone know if the SEIE does protect against it? Wacko Jack O   17:49, 7 April 2009 (UTC)

"The bends" isn't an issue with SEIE as it is with scuba divers. While at depth, submariners are in a pressurized tube, no different than if they were standing at sea level (14.7 psi). Thus, when they eject from the SEIE, they have no built-up nitrogen bubbles in their system as a scuba diver does if he was diving at 100 feet. A scuba diver at 100 feet has 4 times surface pressure on his body or about 58.8 PSI. It doesn't matter if a submariner is 10 feet deep or 1500 feet deep, he still only has 14.7 psi pressure on his body as long as the pressure hull is intact. The emergency ascent from the SEIE at 600 feet takes about 9 seconds normally, so there is no time for nitrogen bubbles to build up in their system on the way up.

What has killed the Navy SEALS who have attempted to exit the SEIE at 600 feet has been embolism. Although the Navy claims the SEIE can be used at depths up to 600 feet, no human has survived it. Of the three navy SEALs that volunteered to do it, all three died of embolisms. From what i understand of the classified attempts where all three divers perished, the expansion of the gases in the 9 second rocket to the surface is deadly. SCUBA divers are taught to "never hold their breathe" and to exhale on an uncontrolled ascent to prevent embolisms and collapsed lungs. While that works at 100 or 130 feet from recreational scuba diving limits, the amount of expanding gases and the speed of the expanding gasses is simply too much to fast for the lungs to manage going from 600 feet to surface that fast. Having trained on the SEIE myself, exiting the sub at 160 feet depth you shoot up like a ballistic missile, screaming all the way up.

I simply doubt it's practical to go from 600 feet depth to sea level in 9 seconds without Boyles law shredding your lungs. The human throat just can't expel that amount of escaping gas fast enough. The trachea is smaller than a garden hose. Only so much gas can pass thru it until the pressure in the lungs causes the alveoli to burst. — Preceding unsigned comment added by 71.48.0.112 (talk) 07:32, 15 January 2019 (UTC)