Nitrox

[Uncle Pug]

Originally posted by ucladiver
-Should I do that first?

-Where can I get some good info about Nitrox, why its safer, what are the tradeoffs associated with that increased safety, etc..

-I just spent some decent $$ on an APEKS TX40 + TX40 Octo, tank etc.. How much is it gonna cost me to get something Nitrox Safe?

1) Nitrox

2) Someone will be along shortly with links to Cobb's website and some others but basically:
advantages- longer NDL times, shorter S.I., longer repetive dives, increased safety if using air tables with nitrox
disadvantages- increased cost of fills
dangers- oxygen toxicity potential if exceeding MOD or O2 clock
myths- not as narcotic, increased cost (gas is the cheapest part of diving!), special regulators/equipment needed, deep diving gas, devil gas

3) you already have a regulator that is supposed to handle EAN40... this is not a big deal. You probably won't be (shouldn't be) diving anything other than EAN32. Shops that PP blend nitrox by putting straight O2 into the cylinder will whine about wanting the tank to be O2 cleaned for safety... you can't fight their phobias and they probably won't be satisfied with you rinsing the jug out with Simple Green so pay them the ~$30 to clean your tank and be done with it. I clean all my own tanks and haven't had one blow up yet.... I have two AL40 with 3000psi of O2 in them sitting out in the garage right now... tanks I cleaned with Simple Green.

 

[kelpmermaid]

can be hard to find, but it is out there. I think a big part of why it is not used more here is basic diveboat/shop economics. A lot of our trips to dive sites are long - two hours to Catalina. Unlike areas with shorter hops to the sites, on most boats here, divers take one tank that is refilled on board. That means that both the shop and the boat have to have the capability of pumping nitrox, and that's a big investment for a return that is not guaranteed.

 

[landlocked]

I recently certified open water (about 3 months ago) logged a couple of dives and promptly signed up for Nitrox. Last week I certified for Nitrox. I have a couple of thoughts. The dive charts take some practice before you become both competent and confident in using them. Computers can simplfy things but still take some practice. My dive partner has struggled with both. I think that introducing Nitrox charts and computers into a basic open water class would be a little premature simply because of the added complexity. A bad analogy but, many mathematical problems can be solved more precisely using calculus than with algebra yet algebra is still taught first. IMO, a little practice with air before adding additional charts and/or computer comlexities is a good idea. Some might say that charts aren't necessary for Nitrox as long as you stay with EAN32, 100 feet and watch your dive times. This, I think, demeans the consequence of error in using Nitrox. If a new student makes a mistake and gets a case of the bends, they will probably live. On the other hand, convultions underwater scare me! Nitrox needs to be respected. I think a little practice with the charts, computers etc. is well advised before jumping into the added complexities that Nitrox introduces.

That being said, a little familiarization as to what Nitrox is and that it may be the next logical step would certainly not be out of place in a basic OW class.

Incidently, my understanding is that Nitox is fairly new to the realms of rec diving having only recently come to us from the loftier reaches of the technical diving arena. How long has Nitrox been part of recreational diving? Three or four years? Just wondering.

 

[Uncle Pug]

Originally posted by landlocked
On the other hand, convultions underwater scare me! Nitrox needs to be respected.

This is the crux of the matter... fear...

Same kind of fear in this statement:
"I would rather travel across country by car because if you run out of gas you still live.... run out of gas in an airplane and you're dead!"

Anyone know what the safety recorded comparison between flying and driving is?

OxTox is a real consideration... but not one that is realistic.
By the way you can OxTox on EAN21 too... if you take it too deep... but chances are you will run into other more severe difficulties on your way to doin' the Funky Chicken.

 

[NINman]

Ok, so I get my tank O2 cleaned along with my reg, can I still use it with AIR if for some reason thats all that is available? If I do, do I need to get the equipment O2 Cleaned again?

Thanks in advance and as always please be nice!!!

 

[Uncle Pug]

Originally posted by NINman
do I need to get the equipment O2 Cleaned again?

Hi Brad, I'm almost always nice....

The answer to your question depends upon how paranoid your LDS is.... if you have your tank filled with air that is so contaminated with oil that it poses a hazard for PP blending then you certainly shouldn't be breathing the stuff.

But ignorant or unscrupulous LDS nitrox fillers will sometimes demand that you have the tank cleaned if it has been used with anything less than hyperfiltered air. This is unnecessary and especially so if they are using EAN40 to PP mix with. However there is absolutely no reason to have your regulators re-cleaned because they will never see anything above EAN40 and probably more like a sane EAN32!!

As for the non-hyperfiltered air contaminating your tank... shoot... why are they selling air that is that bad in the first place!!! Most compressors putting out grade E air will also test out good for PP blending as well.

If I had an LDS that was that uneducated and paranoid or that educated but greedy I would get my gas from somewhere else.

And so I did.

 

[NINman]

Thanks PUG .. The one LDS I visit stated just that. He said that they blend before so the cleaning of the tank isn't needed. I want to get certified, but I didn't want to spend any more money then I have already on a NITROX reg, if you know what I mean. You defiantly cleared it up for me and I just might sign up and get the O-Rings replaced in my reg. I have the Sherwood Oasis, anyone know what O-Rings are used in that or if it is NITROX ready? Thanks ya-all ..

And yes you are always nice .. and sometimes brutally honest!!

I have learned lots from ya that’s for sure. Maybe once I convert to the DIR Philosophy we can dive together sometime. Might be 5 - 10 years down the road though.

 

[Uncle Pug]

Originally posted by NINman
Maybe once I convert to the DIR Philosophy we can dive together sometime. Might be 5 - 10 years down the road though.

Nah... you don't have to convert for me to dive with you.... but it is more like 3000 miles down the road for one of us.... unless we meet for a stock tank dive somewhere in Kansas.

 

[ucladiver]

Originally posted by Uncle Pug
3) you already have a regulator that is supposed to handle EAN40... this is not a big deal. You probably won't be (shouldn't be) diving anything other than EAN32.

Uncle Pug:
Just to be clear, I do not have the "Nitrox" (Yellow & Green) TX-40. You say it is already O2 clean for up to EAN40? I assume it has silicone lube and such. At what point does that stuff start to be a problem? Thanks!

 

[Uncle Pug]

Originally posted by ucladiver
Just to be clear, I do not have the "Nitrox" (Yellow & Green) TX-40. You say it is already O2 clean for up to EAN40? I assume it has silicone lube and such. At what point does that stuff start to be a problem? Thanks!

Supposedly at 40%... but it is only the hp side of the 1st stage that is exposed to the elevated PO2 anyway. I have Apeks regs that I take right out of the box and stick on a jug of EAN32 without even thinking about it. I have Apeks regs that I stick on a bottle of 3K psi O2 and I think about it... they are O2 serviced: that means O2 clean and O2 compatible... than means that any contaminants have been cleaned out and all materials are compatible with O2 (Christolube/Krytox and Viton o-rings.)

Now if this is a concern for you then you should take care of the issue... either by doing the work yourself or having someone else do it. I do nothing special to my Nitrox regs but I do O2 service or have O2 serviced my deco regs. I do not use my deco regs on somebody elses filthy~oily~scummy air bottles.... but since all my EAN32 is cleaner that anybody elses air I will use them for my blend of nitrox.

When you take your regulator into be serviced be sure to tell them that you are using it for nitrox and want it O2 compatible. This just means using a different lube and o-ring a so it shouldn't be a big deal.... I took a good to go Apeks reg into a shop once to have it serviced and (my fault for going there) they loaded the thing with silicone! Shoot.... had to have it redone right.

So I quess the bottom line is... what are you going to use the thing for? EAN32? I would dive it. O2? I would clean it.