AOW / Nitrox Class Questions

[rottielover]

Hey all,

I've tried to read just about every thread I could, but I'm still left with some questions specific to my buddy and I *my wife*...

Last year we were scheduled to do our AOW on a trip to Cozumel, but that is when Wilma hit, and we didn't go... We've already paid for AOW and our LDS said they will work with us to figure out if we want to do our AOW in the local Quarry (Mermet Springs) or on another trip etc...

We've also been thinking about the Nitrox class.

So with about 15 total dives that don't include pool dives ...

Is there any benifit to doing Nitrox before AOW? For instance doing some of the AOW dives on nitrox? Or should it be the other way around, do AOW then Nitrox?

Another thing I'm confused on after reading a bunch of threads, is the whole O2 clean issue. It sounds like some people are switching between Air and Nitrox and nothing needs to be done to your reg or bc as long as they are "Nitrox compatible"? Yet some have mentioned O2 cleaning if your going to switch between Air and Nitrox?? So I guess the question is, does something special have to be done to my reg or bc if I want to switch between Air and Nitrox ? I guess I'm wondering this mostly because I'm not sure if you can do class's on Nitrox once nitrox certified?

I'm sorry if I missed the answers to these questions on other threads, it's just that it's almost the start of the "season" here in the midwest (warmer temps on the way), and I'd like to get our class schedules sorted out pretty soon so that we can get into the scheduled classes before they fill up.

OH, before I forget, we're not planning a big trip this year, we pretty much spent our trip budget last year when we went to Maui instead of Coz. So this year we're planning on going to the quarry for our dive trips and saving up some extra money to do another "ocean trip" next year. So I figured if there's going to be a benifit, might as well take advantage of class packages at the LDS this year (IE we get a discount based on the number of classes you sign up for). That way we'll be ready for our next big dive trip.

I would really appricate hearing your thoughts on all of this. Thanks in advance!

 

[DBailey]

1. Your dives for Nitrox certification required you to breathe underwater. If you do Nitrox alone, then you go out and do fun dives on Nitrox. A lot of people like to double Nitrox up with another specialty or AOW. If you double up, there should be a double briefing and double debriefing (one for Nitrox and one for the other class).

2. All newer gear is O2 clean enough to handle up to 40% O2. So there is no need to be worried about your BC or regs unless they are antiques. The O2 clean issue comes mainly to tanks where during a fill the shop will use pure O2 then mix with air until it is the correct mix.

3. Diving somewhere is always better than not diving.

 

[Lead_carrier]

If you plan on doing nitrox and can get a discount by signing up for more classes. Do it. As far as any big advantage in doing AOW with it, naa. Don't worry about the O2 cleaning issue unless you own your own tanks. Even then, swapping between nitrox and air is no issue as long as the air is "clean" or O2 compatible air. Most all regulators are nitrox compatible since the mixtures are below 40%. If you get feed a line that your regs must be cleaned for nitrox use, then you are getting fed a line.

 

[Divin'Papaw]

I'm taking both AOW and EAN in June. Technically, I'm doing them together, not one before the other. I'll have two nights of class for AOW and one night for EAN and then my 2 needed EAN dives will overlap with and be 2 of my 5 needed dives for AOW.

Regarding equipment, the O2 clean bit becomes critical with tanks, especially if they are filled via the partial pressure method. As far as your regs go, from what I've read, as long as they are EAN compatible, switching between EAN and air is fine. At only 40% max oxygen for recreational nitrox, there really isn't any danger for the regulators. You'll find post after post after post of folks who switch from EAN to air and back all the time and have never had a problem. However, if you have your own tanks, get them O2 cleaned or keep them O2 clean if they're new.

 

[Rick Murchison]

As far as "when should I take Nitrox?"
It really doesn't matter. There are no new in-water skills to learn - all the new things are in planning, analysing and transporting your tanks, so you could actually learn Nitrox as part of your open water classwork - and some do. As for when things need to be oxygen clean, that has to do with how the gas is prepared... IOW as a Nitrox diver it's not really your problem unless you own your own tanks - and under any circumstances all that will be explained in the class..
Rick

 

[rottielover]

Great! Thanks for the super fast responses!!!

Our reg's and bc's were purchased last year and the material's that came with them said they were "ready" for Enriched air. We don't own tanks, since it's easier for us to rent them from the LDS (and we joined the LDS dive club so we get a further discount when we do rent tanks) so it's hard to justify the cost of owning our own tanks right now, until we do a LOT more diving, but I'm sure that day will come

I think I was mostly concerned with switching between air and nitrox if there were some requirement to "O2 clean" things between switching, since that's not the case, all the better. I wasn't sure if you were "allowed" to do class dives on Nitrox (assuming of course your nitrox certified). I was thinking that PADI might require you to be on air or something, but it sounds to me like many people "double up" the classes as it is.

Sounds great, I'll have a chat with the LDS and instructors as well, let them know my thoughts and see if they "double" up the classes or whatnot.

Sounds like I have a pretty good plan for this year then Since we're not doing any big trips, it will be a great summer to get some more certs done. That and it will in effect "force" us to go and dive, rather than it being a Friday and saying "oh, maybe we can go to the quarry this weekend" and then not end up going LOL.

 

[Lukiedukie]

I am doing my AOW/ Nitrox together, I do not see any advantage other then I am doing both on a trip. Outside of that and maybe getting the shop to throw in a specality or two for free there is no real advantage for me. Talk to your shop and instructor. I have been told many things recently by some LDS and I now know that I do not have to have my regs o2 clean as the a re ready for nitrox up to 40%. If you have newer gear you should be fine. Good luck and have fun!!!!!!!!!

 

[Divin'Papaw]

Sounds like I have a pretty good plan for this year then Since we're not doing any big trips, it will be a great summer to get some more certs done. That and it will in effect "force" us to go and dive, rather than it being a Friday and saying "oh, maybe we can go to the quarry this weekend" and then not end up going LOL.

When you're planning a trip to Mermet, be sure and let us know via a post to one or more of these forums. There are many divers in the midwest who might like to meet you there, such as myself!

http://www.scubaboard.com/forumdisplay.php?f=58
http://www.scubaboard.com/forumdisplay.php?f=188
http://www.scubaboard.com/forumdisplay.php?f=312

 

[nauidiver2004]

The benefit of taking a nitrox course along with AOW or any other course is your shop may give you a discount on the course fee. Whether there is a real benefit to actually diving with EANx (nitrox) as a requirement to the nitrox course has been debated here several times in other threads and it boils down to you as a student. All of the information will be presented to you in the classroom portion of the nitrox class, but for me, actually planning and executing a few dives under an instructor really gave me a confidence boost and confirmed (for myself) that I understood how to use the gas.

Information about requirements for gear such as o2 cleaning will be covered in your course. For recreational divers using EAN40 or less (that would be you and me) have very few equipment concerns. The most prominate issue is the inside you your tank and it's valve. If your shop uses a method called partial pressure to fill your tank with nitrox then they MUST be O2 clean. Partial pressure filling is a process where they will partially fill your tank with pure O2, then top it off with normal air. Basically you are taking air and enriching it with oxygen hence the teamr Enriched Air Nitrox (EAN). because the first part of the process deals with pure O2 the tank must be O2 clean. once the air is added the pure O2 is diluted and becomes less of a fire hazard. The other meathod in obtaining an EANx fill is called 'banking'. This is when the shop uses their own big tanks to blend oxygen and air in the desired amounts then fill your tank with the 'premixed' gas. Under these circumstances your tank would not have to be O2 clean because it would not come in contact with pure O2.

You can use a tank cleaned and labeled for nitrox with just plain air so long as the air is properly filtered. Any shop that sells nitrox, either by partial pressure method or banking premix, will have air clean enough to fill your tank with. They will have a good understanding of the dangers involved in contaminating a tank and wouldn't do it. (Filling an unclean tank is dangerous for the fill operator, not you the diver. However it is not to be taken lightly, it could kill someone and for this reason operators are careful about what tanks they fill with nitrox)

I have oversimplified all of this just to give you a basic idea. If you can save some $$ by combining your classes I would suggest it. If not, then don't worry about it. As far as gear is concerned, If your planning on buying a regulator or a tank just let your shop know that you want to take the nitrox course and they will steer you in the right direction.

 

[RonFrank]

Most shops will add Nitrox to AOW for an additional $90 vs. the $150 they charge for just the Nitrox class. That is the only advantage to doubling up the classes.

Nitrox is a good thing to have, but unless you are doing 80feet query dives on a regular basis, and are looking for more BT or more of a safety margin than diving air is fine. Diving Nitrox is a bit more expensive. There are times when Nitrox is a very good card to have along. Diving Jupiter where the reefs are at 70~80fsw is a perfect example of where Nitrox will increase your BT assuming one does not suck down the air before the NDL is reached.

As others have indicated, O2 clean in rec diving is a tank thing.