Air and its components

[BlackPatch]

Hey all.

Looking at the Deep Air thread and all the pedantic crap that is being traded I have a question to ask,

This is composition of air in percent by volume, at sea level at 15°C and 101325 Pa.Nitrogen -- N2 -- 78.084%
Oxygen -- O2 -- 20.9476%
Argon -- Ar -- 0.934%
Carbon Dioxide -- CO2 -- 0.0314%
Neon -- Ne -- 0.001818%
Methane -- CH4 -- 0.0002%
Helium -- He -- 0.000524%
Krypton -- Kr -- 0.000114%
Hydrogen -- H2 -- 0.00005%
Xenon -- Xe -- 0.0000087%
Ozone -- O3 -- 0.000007%
Nitrogen Dioxide -- NO2 -- 0.000002%
Iodine -- I2 -- 0.000001%
Carbon Monoxide -- CO -- trace
Ammonia -- NH3 -- trace

what effect, or supposed effect on Human Tissue, does breathing the Rare and trace compounds at depth present ?
Is there quantifiable data that suggests either way any effect, be it positive or negative, on Human tissue ?

Is this question indeed moot as such small quantities of each compound exist in Air and a composition?

Interested to know from those who would like to venture an opinion either from a scientific standpoint or completely speculative.

Thanks in advance Ladies, Gentlemen and all those not too sure...

 

[DuboisP]

argon, neon, helium, hydrogen are really good to go deep.
xenon is for your lamp
you ave methane in your body
i have krypton when i dive with my SuperMan underpants over my suit

and i'm alive, so, don't worry

 

[Doppler]

... all the pedantic crap...

Yeah, that about sums it up.

For the partial pressure of all the trace and rare elements in air... those not removed by a compressor's filter system (water vapor for example which is not in your list of ingredients)... to have any impact on a diver, the main constituents (oxygen and nitrogen) would have killed them much shallower in the water column.

*And I thought I was a pendant*

 

[BlackPatch]

Yeah, that about sums it up.

For the partial pressure of all the trace and rare elements in air... those not removed by a compressor's filter system (water vapor for example which is not in your list of ingredients)... to have any impact on a diver, the main constituents (oxygen and nitrogen) would have killed them much shallower in the water column.

*And I thought I was a pendant*

Doppler,

Thanks for the witty "Pendant" answer, however I do understand that the O2 and N2 would have had an effect long before any of the Rare and Trace elements. I am by no means an expert and gained what little knowledge I have through reading Chemistry books, my Dive Instructors, OW and Nitrox courses and research online. By no means do I know everything. Most days I profess to know nothing...

However, and this is my fault here Doppler, I guess I was not clear.
What I want to know is: has study been done on the Rare and Trace elements and there effects during breathing at Depth ? Somewhat similar to the DCIEM experiments on IGN / N2 Narc and the like, in the 70's. Both Hyperbaric and Wet.

I know that HyDreliOx is used to reduce symptoms of HPNS below 300M and also that Hydrogen has a noticeably lesser narcotic effect than Nitrogen due to its Molecular weight.

I know that ArgOx is, essentially, a theoretical Breathing Gas Mixture. Testing with Astronauts caused higher levels of Decompression sickness than with other mixtures.

I understand the reasons for using TriMix and Heliox, these gas mixtures are not in question, neither is the notion of Deep Air.

What I am asking is, during scientific evaluations on IGN / N2 Narc / Ox Tox Did the trace and Rare compounds ever factor in to the equation as having an effect on Human Tissue ?
If Yes, then what were the Effects ?
If No, then why not?
Is it due to the filtration Systems on the Compressors?
Is it purely down to the quantities present not being enough to have an effect on Human Tissue.

Once again. I thank you for the replies and the imparting of wisdom.

 

[Dsix36]

The way it was explained to me is that the trace amounts are so small that for them to be able to have any effect on a diver, from higher partial pressures of them at depth, the diver would have to remain submerged at extreme depth for days at a time.

Basically a moot point is what I got from it.

 

[knotical]

I'll speculate that since nitrogen percentages are lowered with most (all?) non-air mixes used in scuba, then percentages of all other "rare" components will proportionally be lowered, and therefore not likely to be a factor.
Without practical reason to test more gases, there's probably been little or no funding to test other than those already tested.

 

[Mr Carcharodon]

Argon is more solubile in blood than nitrogen and for that reason is a poor choice for a diving mix. There was a study that showed solubility correlates with narcotic potential. That explains why helium is relatively desirable gas.

 

[altaskier]

Helium, Neon, Argon, Krypton, and Xenon are all noble gases; their electron orbitals are full so they are chemically non-reactive. That's why they stay in the atmosphere (they don't like to bind with the surfaces of anything and stick), and it's also why they don't have any real physiological effect.

---------- Post added June 6th, 2013 at 09:14 PM ----------

There was a study that showed solubility correlates with narcotic potential. That explains why helium is relatively desirable gas.

Isn't helium really, really soluble but non-reactive?

 

[CT-Rich]

small atoms like He will diffuse in to and out of tissue more readily than larger atoms like Argon. Another advantage of a gas like helium is that it is 100% inert. Nitrogen and oxygen start to behave differently under pressure, creating the side effects that are not desirable. A gas like helium can be eliminated more quickly during decompression by eliminating it from your deco gas, thus increase the diffusion gradient and allowing it to escape from tissue faster. That reduces the amount of time spent hanging on a line and reduces the likelihood of DCS.

Argon being a much larger atom is a better insulator than smaller atoms or molecules because it transmits energy much less quickly than other atoms.

The other noble gasses, I imagine would work to varying degree as an insulator or in Breathing mixtures based on their molecular weight. Hydrogen gas, (H2) might have some value as a gas, but its explosive nature and the fact that it is reactive might make it less for diving (and zepplins).

I am not a mixed air diver, so those that know more, feel free to correct me.

 

[AfterDark]

That's why they call'em trace gases, there's not enough to matter.