You don’t want the nitrogen percentage to be too high or you run the risk of eutrophication.
The only real danger of too much helium is sounding like Dory when talking underwater.
There is an amazing audio tape where an astronaut who has been living in a helium enriched underwater laboratory for a month gets a phone call from President Johnson.
Got confused by “nitrogen”
The air we breathe is 21% oxygen 78% nitrogen and 1% other stuff. For scuba diving increased pressure at depth on boards more nitrogen in your body than normal so when you surface that extra nitrogen can form bubbles in places which shouldn’t have bubbles and that can lead to injury/ death.
Scuba diving is a lot of fun. I encourage a9nyone vaguely interested to ho to their local scuba shop and do a demo dive.
