Once you go Nitrox, do you use "standard" air?

[ScubaPolishPete]

We'll be taking our AOW shortly, and when you sign-up for that our LDS gives a discount on the Nitrox course/cert.

So...working on that study material now.

Anyway, whilst planning for future tank purchases and keeping my eye on Craigslist just in case, I found myself asking this:

Once we dive Nitrox, will we dive on regular air? Or will we prefer Nitrox, and make that our choice for air whenever possible. How does that affect our tank purchases?

Figure our needs are for local Midwest diving (quarries and Lake Michigan), with possible summer trips where we wouldn't be bringing tanks along.

I've dove with steel and aluminum, and prefer steel for it's added weight (less weights to carry on self) and even buoyancy characteristics. Additionally, a little extra psi doesn't hurt. My wife feels the same way. Thus, when we're finally ready to purchase tanks, we'd like to go steel. However, it's tempting to just pickup some AL80's for now as the cost of 2 tanks/valves is essentially the cost of 1 steel setup.

I guess my questions are for future planning, trying to get some input from the experienced who have been through this.

Should we stick with just steel as we prefer those?
Should we stick with just one set of tanks (Nitrox) because why dive standard air in the future?
Should we pickup a set of steels and a set of aluminum (just because they're cheaper) and use one set for air, and one for Nitrox because we won't just dive Nitrox, we'll dive standard air as well?

At the quarries and the lakes, I see folks with "Nitrox" tanks (labeled, and presumably diving Nitrox), as well as folks I know are Nitrox certified but diving regular air. Never occurred to me to ask why they're diving what their diving that day until now, but since it's 9pm, figured I'd shoot this here for some conversation. (my though off hand would be just fill cost being the deciding factor, with $4 or so being the difference per tank around here).

 

[fjpatrum]

I've had my Nitrox cert for a little over a year and I think I've only done 3 dives on Nitrox. There's no point if you're not going to do repetitive diving or semi-deep dives, in my opinion. I save the $4 extra dollars for a fill (at my LDS) and spend it on other things. If I need Nitrox, I buy Nitrox. If I don't need Nitrox, I buy air.

 

[toddthecat]

This thread is going to explode into a dozen pages fairly quickly. It's a personal preference thing and as said above, it depends on what your dive profile for the day looks like. Some people don't care, some use it as needed, and then you've got the group who worship it as a magical gas that turns people into the 6 Million Dollar Man. I'm surprised I haven't seen them walking around with one little pony tank of nitrox and a nasal canula in the grocery store and hearing *pssss* every few seconds. You'd swear they'd just switch and breathe it all the time...

 

[James R]

I rarely use enriched air for local diving, as it's not really needed for recreational dives and it's a bit harder to get (it's not banked here).

I use it frequently on trips. Last month in Bonaire I used 28 tanks of EANx32 or 33 and just 4 tanks of air, as an example.

 

[dfx]

If it's free, I'll probably use it. Otherwise I may consider it if I think i might get close to NDL on air.

 

[tplyons]

Once we dive Nitrox, will we dive on regular air? ​

Once diving Nitrox, I would without a doubt say you will still dive "regular" air. It's much cheaper, and the benefits of diving Nitrox don't always warrant the added cost. If I'm doing boat dives and trying to get three into an 8 hour day, Nitrox is a Godsend. However, if I'm doing shore dives at the local quarry, I have all day to get those three dives in, so a longer surface interval will essentially have the same effect on increasing bottom time per dive.

Or will we prefer Nitrox, and make that our choice for air whenever possible? ​

In my opinion, there is a time and a place for Nitrox. If it wasn't so expensive and time consuming to fill, I would dive it all the time. But as I said above, the benefits don't always outweigh the costs.

How does that affect our tank purchases? ​

This depends on how your LDS fills tanks. If it banks 32% or another fill, or uses continuous blending, your tanks will not come in contact with anything greater than 40% oxygen, and this is treated the same as air, meaning your tanks will not need to be O2 cleaned and this will have almost zero effect on your tank purchases. On the other hand, if your LDS uses partial pressure filling, your tanks will need to be O2 cleaned since they will come in contact with 100% oxygen. If this is the case, to properly maintain the oxygen clean condition, you will need to fill only with hyper-filtered Modified Grade E air, which is filtered more than regular compressed air. ​

Should we stick with just steel as we prefer those? I would say yes, it is, in my opinion, easier to stay consistent with tanks to keep your trim and weighting consistent.

Should we stick with just one set of tanks (Nitrox) because why dive standard air in the future? My steel tanks are oxygen cleaned, but are usually filled with air.

Should we pickup a set of steels and a set of aluminum (just because they're cheaper) and use one set for air, and one for Nitrox because we won't just dive Nitrox, we'll dive standard air as well? I had this same "brilliant" idea when I was buying tanks. Needless to say, since buying my steel tanks, my aluminum 80's haven't seen any action, except for testing regulators and having a spare in my car in case I want to get a third short dive in.

At the quarries and the lakes, I see folks with "Nitrox" tanks (labeled, and presumably diving Nitrox), as well as folks I know are Nitrox certified but diving regular air. Just remember these Nitrox bands don't necessarily mean that's what is in the tanks. Only the contents label will tell you what is actually in the tank. More often than not, mine are full of EAN21 (better known as air).

My opinion? Skip buying the aluminums, go straight for steel. Just find out what sort of Nitrox fills you can get locally. If you ever anticipate getting fills somewhere that does partial pressure blending, you will need to have your tanks O2 cleaned, and then make sure that all the air fills you get use Modified Grade E air.​

 

[Garth]

Nitrox stickers are ridiculous however I believe using nitrox is necessary to enjoy no deco diving in the 90-130ft diving for recreational perspective. Any tank you plan to use should be fine steel or aluminum.
Steel for those who dive dry.
Aluminum or steel for those who commonly dive wet.

Depending on your local dive shop they may have banked intros which doesn't require oxygen cleaning.

Get you intros because you will be able to spend more time at depth. It will not make you more money at work, it won't get you that promotion, and it won't provide you a feeling of euphoria that air couldn't provide.

 

[toddthecat]

however I believe intoxicating is necessary to enjoy no deco diving in the 90-130ft diving

Probably not a good idea to dive intoxicated I can have a good time at 90-130ft without a few beers before the dive :banana:

 

[JahJahwarrior]

I've been diving air at a local shallow site, but only because the dive shop closest to it doesn't bank Nx and the stickers on those tanks don't indicate the tanks are o2 cleaned for partial pressure blending, even though they are. Works just fine but it makes for a non uniform tank farm.

Of course I also sometimes use air even in my doubles or side mount tanks, as it is perfect for sites where you don't know what depth to expect. No need to always dive nitrox, but I do like to whenever the dive allows for it, including my ability to plan to get a tank filled in time to catch the tide and going to the further away shop that banks it!

 

[Garth]

Crap damn auto correct. Let me be clear that is not what I wanted to write. I meant to say intros shines in the 90-120range.