🚀 go-pugleaf

In article <23966@galaxy.ucr.edu>, judson@watserv.ucr.edu (Mike Judson)
wrote:

> 
> Sorry, but being a chemist and a scuba diver, I can tell you that you are
> both wrong.  Nitrogen narcosis (the bends) is caused by nitrogen in the
> blood.  When scuba diving and breathing compressed air, a person will be
> breathing nitrogen under water.  This is because 80% of air is nitrogen.
> As he breathes this air, nitrogen will be absorbed into the blood stream.
> Then, because of Boyle's law, as the diver ascends, the nitrogen gas wil
> expand in the blood.  If there is too much nitrogen in the blood, the

NO, NO, NO, NO, NO.  This has already been rehashed several times in this
forum in the last month or so.  Nitrogen Narcosis and the Bends are two
distinct phenomena. The bends are caused by disolved nitrogen coming out of
solution upon ascent, as you describe.  Nitrogen Narcosis is a drugged-like
state (thus the word "Narcosis") caused by an interraction between high
levels of blood nitrogen and the brain chemistry.  Since it if a function
of disolved blood nitrogen, it tends to happen on descent, rather than
ascent.  It comes on very suddenly (people I know who have experienced it
say it feels like a switch being thrown), and disappears just as suddenly
on ascent.  In addition, it is completely unpredictable:  A person may dive
to 100 feet one day with no problem, then hit narcosis at 80 feet on
another day.  

> The reason why you do not want to breath pure oxygen is because at extreme
> depths, oxygen becomes poisonous.

This is true.  The thing that limits dives on straight air (20%O2, 80%N2)
to 150 feet is that at partial pressures of over 1 atm, oxegen becomes
poisonous and can result in severe seizures and convultions.

-tony

>>usual disclaimer<<