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In 2025, People Will Try Living in This Underwater Habitat
(spectrum.ieee.org)
This is a most excellent place for technology news and articles.
Apparently when doing saturation diving like that you can't even understand what the other person says, between the helium and the pressure the voice is too distorted to be intelligible.
You can communicate with a computer that transforms your voice to be intelligible but it is really not a pleasant conversation so you can stay there for weeks without having a conversation except for the bare minimum.