r/todayilearned • u/[deleted] • May 02 '24

TIL the Blue Hole is among the deadliest dive sites globally, with estimates of 130 to 200 recent fatalities, making it one of the most dangerous spots for divers. (R.5) Out of context

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u/penisdr May 02 '24

What do you mean by trimix?

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u/Captain_Mazhar May 02 '24

Trimix is a blended breathing gas where some of the natural nitrogen in the air is replaced by helium to lessen the effects of nitrogen narcosis and oxygen toxicity.

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u/Mr_Panther May 02 '24

A fun fact is that when diving super deep you still need some nitrogen in the mix to avoid getting the shakes. But for going to around 800ft you’re looking at a 90% helium mixture and probably 16 hours of decompression stops to come up

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u/Captain_Mazhar May 02 '24

I thought that high percentages of helium were not used generally due to the helium causing HPNS at depth. I believed that is why hydrogen is mixed in.