Differences in Air quality

[popolarbear]

I know we have roughly visited this question, but i am curious to see what the board has to say.

without naming any names, i am curious if there it is possible that some differences of air exist in fills. we had a lengthy discussion i think on moisture levels in fills. and if i understand what the conclusion was that at high pressure what little moisture is in the air(and not removed) is in gas form. i am under the impression that i have had fills at some stores that were extremely dry to the point that it dried my mouth after breathing for some time, but other fills didn't do that. also I'm very interested in understanding the difference of different oils used to lubricate these compressors. most fill stations use oil technology to compress the air, then remove the oil in a separate stage. Oil in fine suspension will kill the breather by coating inside membrane of lung permanently. but some manufacturers use oils that break down. I think anderol 500, anderol 750 are examples of synthetic food grade oils. but are these also examples of oils that the body can actually break down or only that they are nontoxic. are all the compressor(in the US) now in use using these "food oils"  or is it still possible to get a fill that had "bad" oil used that made it Thur the oil filtration? i think in some remote areas the problem of oil contaminate was lethal...

curious what the board sayeth.

[Chris H]

There are several different criteria for breathing air testing.  There is a decent rundown of some of the requirements on the Dive Gear Express website.



I would expect that most of the shops would be able to produce their air test results if you ask.   

The other option is to buy your own compressor.   I went that route and it is so convenient.  I don't think I'm saving any money, but having a full Trimix fill station in my garage sure is handy.

[arcFlash]

I don't know anything about oil or compressors beyond the lay person on the street. I get all my fills from Scuba Center and some of my dives make dry mouth and some do not. It has more to do with how warm I am, if I'm overheating in my suit or getting cold and my breathing goes up.

I think you may be looking too hard for a reason when 'chaos theory' applies. A dive is highly susceptible to initial conditions like mood and sun light levels. I'm not saying it controls the quality of a dive but if you've even wished for the clouds to clear on a surface interval and they do and your mood elevates, your repetitive dive was likely more enjoyable because of it.

[Hydro]

This reminds me of my organic professor telling us about an organic farmer talking to him

Gas chemistry of air aside, there are more factors going on with your body than what is getting released from your tank, are you hydrated enough is the first thing id question, if you have enough biologically available water you arnt going to notice as fast.

I might go on later but I have to pick someone up.

[Chris H]

I understand there is a lot of discussion about hydration when diving, but anytime anybody mentions that I can't help but think of this clip

[popolarbear]

actually i was hoping for a more detailed explanation of particularly oil contamination. as i was reading that in the rare event of oil contamination from oil based compressors(which most compressors are), that some types of oil are lethal because the body can not remove the oil coating from the lung membrane, and there currently is no medical cure for this type of accident.  my curiosity is to have a more deeper understanding of this toxic process, and what if any backup measures are in place in the scuba industry. are the oils used in these compressors safe if there was a chance contamination. if the oil is not safe, is there a secondary back up filtration method to double remove these from the air stream? as i understand they use food grade oil, but is that to say the food grade oil is something the body can break down and or deal with in the event of contamination to the lung surface?

[Chris H]

I use a Lawrence Factor filter on my compressor.

There are different filters for different applications.  I don't believe the oil would stay airborne within the tank even if you did get some oil through a compressor.  It is heavier than air, or whatever gas you are breathing, and would make a nasty little puddle in the bottom of the tank.  The puddle, would of course be worst case.
Dig around on the Rubicon Foundation website. 

[popolarbear]

who does air testing kits in the twin cities?