Nitrox cylinder bands

[2airishuman]

I recently purchased four cylinders from another diver. Two had yellow-and-green nitrox cylinder bands, and two did not. All four cylinders had been used for a number of years for nitrox and trimix.

I removed the nitrox bands and other decals, and wire brushed the cylinders in preparation for hydro test. There was considerable corrosion under the bands.

Are the nitrox bands widely considered to be necessary for safety reasons? Is there any way to mitigate the corrosion problem?

 

[claymore]

You will get varying answers. As you have found they should be removed for each VIP inspection to check for corrosion/damage. Outdated VIP stickers should also be removed at VIP time. Some shops will require it others will not. Some shops will require the sticker if it is filling with Nitrox some will not. It is still up to you to check your fill and mark it appropriately.
I will not get into the legalities/requirements for tank marking, I will let more knowledgable comment on that.

I pulled all of mine and just mark my Nitrox tanks with Duct tape on the tank shoulder with pressure, date, mix %, MOD and contingency depths.

 

[Patoux01]

They're useless....

I wouldn't use them, unless there's some law about it in your area OR the only shop around requires them...

 

[tomfcrist]

Nitrox bands although widely used are really not necessary. Furthermore, if the inspector is doing the job right during the annual visual inspection, the thing needs to be scraped off completely and a new one can be put on.

From a safety aspect, as long as the Vis sticker notes that the tank is O2 clean and the current mix is annotated on the tank, I see no reason for the big sticker. Additionally, I think having a nitrox sticker on a tank that has trimix in it can be dangerous. We are all taught to analyze our tanks before breathing them, but laziness happens. So if I have a tank with a nitrox band, people may assume it has nitrox in it....they may not assume that it has 12/70 in it. So when they strap it on without analyzing it to scrub the bottom of their boat or to clean the bottom of their pool, they may very well be breathing a hypoxic mix. I suppose that scenario is no different with an unmarked tank, but the lessons learned should remain the same....1) If you own tanks for mixed gas(Nitrox or Trimix), keep it marked with the current mix. 2) Don't grab a random tank that you don't own and just dive it. 3) If you feel the need to put a nitrox band on a tank, make sure the inspector peels that thing off every year when it gets inspected....corrosion happens, its inevitable.

 

[decompression]

As above......

 

[Peter69_56]

I just have oxygen clean stickers on all my tanks now. I don't use the big nitrox stickers. They are not necessary here in OZ. Its more important to have the oxygen clean sticker. I never get my cylinders "Nitrox" clean, I get them oxygen clean. Some places offer nitrox clean but is the same as oxygen, and many places will not blend over 40% if only nitrox clean (not PP fill).

All my cylinders are cleaned and all my air is double filtered for blending.

 

[NAM001]

Here is my 2 cents.

Once upon a time nitrox <40 was treated like air and above that treated like 100%. Now with greater than 40% you put a band on the tank to indicate that no air less than OCA (oxygen compatable air) (grade e hyperfiltered) was to be put in the tanks. with out the band you could put in grade e and still use it for nitrox 40 or less because it was same as air.

Now days the standards are any nitrox 23.5 and 50 psi or above requires the tank to be O2 cleaned. once cleaned it must have no less than OCA or the clean is void. the need for OCA requires the nitrox band on the tank. to insure grade e or less is not introduced into the tank.

Its dumber than dirt, but so are a lot of things.

Here is the nickle.

I must say that so many of your inquiring posts are so far beyond your level that you shouldnt be surprised that some react the way they do , including my self. I understand where you are coming from, You are a analytical and precision kinda of guy but at some point you have to stop experience the not so precise real world and smell the roses. To do that you have to get your OW and then progress through AOW and nitrox to the point where you can benifit by the questions you raise. Your doubles, buoyancy, and other matters will dissappear as they will , for the most part, be answered by instructors during formal training. Many here do not want to be a substitute for formal training.

Well hope this helped some, I am sure we will chat or share posts again.

 

[beester]

An oxygen clean sticker is only valid until the first fill after the cleaning ;-) So it does not proof anything. Same with a nitrox sticker, it doesn't give any reliable information on the contents of the tank.

So both are basically useless. Of course my tanks have been refused from time to time if I fill at an unknown lds, because I had no sticker, but that's because they are ignorant. Other lds will only fill when they know the tanks... this I can understand, specifically if you are partially blending. (so it comes in contact with 100%).

Nitrox stickers so you know what's in the tank is total folly. The only sure way to know what is in your tank is to ANALYSE, ANALYSE, ANALYSE... so analyse and mark it with a bit of ducttape on which you write the expected mix, the analysed mix, date and signature. After a dive pull of the tape.

 

[2airishuman]

.
I must say that so many of your inquiring posts are so far beyond your level that you shouldnt be surprised that some react the way they do , including my self. ... Many here do not want to be a substitute for formal training.

Judging by the replies, this wasn't a question asked solely out of ignorance, because experienced divers disagree on the answer. Also, many of the replies are at odds with what is taught in the class, and by your own admission, some of the requirements are "dumber than dirt." PADI teaches that the cylinder bands are necessary because they could prevent an accident where a non-nitrox certified diver unknowingly uses a nitrox tank without realizing its contents; this dovetails with PADI's teaching in OWD to recognize the bands for what they are. That makes sense, but the replies thus far indicate that it isn't how the real world works. Do you (does anyone?) think we'll cover those nuances in a Nitrox class, that takes place in the classroom with no diving component, where the vast majority of students have no intention to ever do anything besides dive banked 32% and who want the class to conclude as quickly as possible?

Your post was informative. It moved the conversation forward. Thank you. Posts that do nothing but question whether I should be asking the questions I'm asking, on the other hand, are unhelpful.

Please note: This forum has special rules. This forum is intended to be a very friendly, "flame free zone" where divers of any skill level may ask questions about basic scuba topics without fear of being accosted. Please show respect and courtesy at all times. Remember that the inquirer is looking for answers that they can understand. This is a learning zone and consequently, any off-topic or overly harsh responses will be removed.

1) I don't misrepresent my experience
2) I try to avoid expressing an opinion based on secondhand information and on topics where I am not an expert
3) I make an effort to find older threads that address my question before starting a new topic
4) I do not ask questions unless I am genuinely interested in the replies, and I read them all, even the ones where my "stupid question" has produced over 100 responses
5) I try to avoid asking the same question multiple times
6) I pick the most appropriate forum for the posts based on my understanding of the boards.
7) I have paid my dues on other boards where I have patiently answered questions from people new to a particular topic or activity, written introductory articles, and generally given away my knowledge for free.

I am not a mod, but my understanding is that there is a range of forums:
- New Diver and those considering
- Basic
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Nobody is required to reply to my posts. If you and others don't want to be a "substitute for formal training," fine, ignore my posts, or stay away from the basic forums where I understand my posts to be appropriate.

It is my experience that boards only succeed when there are new people posting who don't already have their mind made up.

I have never been involved in a topic or activity that was as hostile to inquiring minds as diving.

 

[tbone1004]

here's my opinion.

Not sure where KWS' info came from on anything over 23.5 requiring things to be O2 clean, but since most of my diving and nitrox fills are in cave country, there are some "rules" that are blissfully ignored. I have yet to see anything official come out saying that, but I'm not current on PSI-PCI so it may be from them.

ANY sticker on the tank is required to be removed at VIP, otherwise you see what is going on above. I personally think stickers on tanks are stupid, and I don't actually put VIP stickers on my steel bottles anymore, and the on the AL80's they get put in the little lip on the bottom. In cave diving, sidemount especially, stickers don't last, so we don't put them on. I would never put nitrox bands on a tank, if the dive op required it, I would throw some of these on
http://www.diveseekers.com/Tank_Wrap_Small_130Ft_Mod_p/gm2778-130.htm