#-Baric chambers are related to pressure; the partial pressure of oxygen is only a coincident controlled by gas mixture. A crucial difference since hermetically sealed chambers like in space actually suffer significant diver-syndromes when going from suit to habitat due to pressure differences between the two and saturation in the space ship for periods of time.
So it’s all relative - related to partial pressures.
Interestingly we can saturation dive to 2700feet sea water with a 54 day decompression using Hydreliox. Which means we could saturation dive and wear T-shirt and jeans on surface of Venus; sans the 900F ambient temp.
Hydrogen narcosis leads to psychedelic effects and psychosis.
A theme I want to explore in a sci-fi book I want to write some day.