Nitrox Question

[Teller]

My son and I will be doing the EAN course in early April. Regular visual inspection sticker is $15/tank, $25 for Nitrox after a $50 O2 clean (I have not done the VIP on the tanks yet this year). Fill cost for air and for premix 32% is the same on fill cards.

Should I get my tanks O2 cleaned and stickered? Assuming I will not be exceeding the depth limits, is there any reason not to use Nitrox regularly? I would assume it would be a benefit, but I do not know what I do not know

TIA

First if your LDS banks 32% and they are telling you that your cylinders must be O2 cleaned find another shop. There is no reason to not use Nitrox as long as it fits into your profile/plan except cost. If cost isnt and issue for you then go for it. Of coarse youll need to monitor your CNS% but I doubt youll even come close to your limits if your just doing recreational diving. Personally I dont use Nitrox unless I need it such as when using it for decompression diving. Good luck.

 

[Jim Lapenta]

I also seriously question why a sticker with a couple extra lines of text that say "O2 clean" is $10 more? Does that mean they use contaminated tools for inspecting tanks that are not going to be O2 clean? Are they O2 cleaning the valve every time and installing o rings and parts that are that much more expensive (they are not by the way)? There is no reason for a shop to charge $10 more on a visual for a nitrox tank. Other than they can I guess.
Or it's a charge for that butt ugly 6 inch wide bumper sticker that is not really needed.

 

[redacted]

There does appear to be a basis in some CGA and other guidelines that call for O2 cleaning for any gas with more than 23.5% O2. But it is usually the PP blenders siting such requirements and not pre-blended suppliers of less the 40% O2. So, the shop may have a justification but I would look for another shop that does not have such a requirement. Also, I can't imagine why a vis on a nitrox tank would cost more than a vis on an air tank. Well, actually I can if the shop required a NITROX wrap on the tank and insists on removing and replacing it with each vis. That would also get me looking for another provider.

Unfortunately, some shops seem to have nitrox policies that seem to be more motivated by their desire to separate divers from their $$ than any real safety concerns. I would probably happily spend more $$ on nitrox fills if it were not for some of these unnecessary requirements (is scams too strong a word?).

 

[RTee]

By the exact same token, if you travel somewhere with your O2 clean tanks and they don't have oxygen compatible air, you just wasted $50 as you need to re-clean your tanks.

gcarter...here you go. As long as you always get your gas from Sh.....y's or a place that has similar quality of air or banked EAN you will not have a problem. However, such commodity is not widespread and you may end up being somewhere where a) they do not have nitrox and b) they have a very basic compressor which would nullify the O clean of your tank(s).

Therefore, it is for you to decide, based on your type of diving and where you intend to do if it would be best to go the O clean route and dedicate your tank(s) to EAN or super purified air only, or keep it the way they are which does allow you to use air and banked EAN up to 40%. One way or the other, you can then just rent tanks for the odd occasions (air tanks or partiallly blended fill tanks from the local DS).

 

[txapacheguy]

Without being familiar with the normal market price of dive shop services in Canada, I will go out on a limb and say that your shop is probably overcharging you a bit.

I agree with the previous posts in that if you are getting premix EAN32, there should be no need for any special servicing. The only justification I can see for that hideous nitrox wrap is to warn other divers that your tank has stuff in it they should not breathe without the proper knowledge, training, analysis, etc. The VIP sticker should indicate the level to which the tank is cleaned and suitable for EAN.

Gcarter, please enjoy your nitrox course. It will give you and your son the foundation to pursue much more challenging and advanced training later on if you choose to, and to make the most of the diving you are doing right now. If you would like to learn more about the different types and levels of tank cleaning, O2 cleaning, visual inspection, and nitrox blending, consider obtaining a copy of Vance Harlow's Oxyhacker's Companion. The book will cost you less than your LDS is charging to O2 service one tank for one year, and it might spark a bit of "do-it-yourself" interest. I feel that book is one of the best deals in the diving community right now.

Safe Diving!!!

Will

 

[gcarter]

gcarter...here you go. As long as you always get your gas from Sh.....y's or a place that has similar quality of air or banked EAN you will not have a problem. However, such commodity is not widespread and you may end up being somewhere where a) they do not have nitrox and b) they have a very basic compressor which would nullify the O clean of your tank(s).

Therefore, it is for you to decide, based on your type of diving and where you intend to do if it would be best to go the O clean route and dedicate your tank(s) to EAN or super purified air only, or keep it the way they are which does allow you to use air and banked EAN up to 40%. One way or the other, you can then just rent tanks for the odd occasions (air tanks or partiallly blended fill tanks from the local DS).

I have fill cards for ~ 80 fills for the "S" shop. I don't plan on travelling with the tanks, so "S" it is.

For the record, I have not been told the tanks need to be O2 cleaned - I was only stating the prices and asking the question. As I have not done the course yet, I am somewhat ignorant on the topic.

As always, I appreciate the many responses.

Cheers!

 

[RTee]

G...my doubles are O clean and so are my two stages. Having said that, my GF sold her two Premix AL 80 cft tanks and purchased two used steel 100cft. She got hers O cleaned. I still have two AL 80cft that I can use with Premix only and that's what I use them for. Like I said, if you use banked 32 it does not matter which way you go...it only becomes important if you go somewhere else. EAN is a great course BTW.

Hey, nothing wrong with S...it is also where I get my fills (Air, EAN, O2) and I still have plenty of leftover cards

 

[bracko]

You haven't taken your class yet, but one of the things you will learn is that there are several ways of making Nitrox. One way is to empty the tank, and put in an amount of pure oxygen, and then top that with air. That's called "partial pressure blending". When a shop makes its Nitrox that way, your tanks and valves have to be O2 cleaned, because they will be exposed to oxygen in concentrations above 40%.

I know I'm being pedantic, slightly off point, nitt picking and annoying by pointing this out, but if you know the starting blend in the tank, pressure and size there's no need to completely drain the tank, is there?

 

[Thalassamania]

Thanks for all the responses. The LDS where we will be doing the course is the one I bought my tanks from and who would be doing the VIP and are the shop that I have a mitt full of fill cards for and...

So I guess the answer is (I don't plan on travelling with my tanks) ask them whether I need the O2 clean or just the VIP, and then dive away on Nitox.

Cheers!!

Not whether, rather why?

 

[redacted]

I know I'm being pedantic, slightly off point, nitt picking and annoying by pointing this out, but if you know the starting blend in the tank, pressure and size there's no need to completely drain the tank, is there?

As long as we are "being pedantic, slightly off point, nitt picking and annoying by pointing this out", Lynn did say that is one way. Depending on the pressure/volume of your O2 supply, it could even be the only way in some cases.