Question NITROX (in less than 40 foot of water)

[scubayinzer412]

its your thing, how do you know its 32%
do you know how to check it?
so in a normal bottle there will be max nitrox 40 thats gives you a MOD of 75F/25M.
dumb it, dive it, or make the course. you also can get it in a online course

 

[formernuke]

Just to reinforce. Even if you trust the fill never dive a tank you didn't personally analyze.

I agree with your decision to get nitrox certified. It is a very useful course for your future diving.

 

[L13]

Just to reinforce. Even if you trust the fill never dive a tank you didn't personally analyze.

How are all the OW divers supposed to follow this advice?

 

[formernuke]

How are all the OW divers supposed to follow this advice?

It's easy, a analyzer takes 2 minutes to learn how to use. And will tell you if it's 21 percent.

 

[ReefHound]

Last time I was in Egypt, yes. After a dive, one of the DMs pointed out the nitrox sticker on one of the customer's tanks and asked if they had intended to dive that since they weren't on the sheet as one of the nitrox divers. The expected "no, what's that, what does it mean" discussion ensued. They didn't know nitrox was a thing and had just grabbed one of the tanks and checked the pressure when switching between dives. (It wasn't always obvious which tanks were which; there were stickers, but they were old, worn, and sometimes reduced to just a few pieces of greenish tape. No other labelling as divers were expected to analyze them themselves.)

I think they were a fairly new OW diver, so at least somewhat unlikely to run into trouble with any 21-32% gas, given their dive profile.

Well, Egypt. Enough said. Where you are doing well if your boat doesn't sink or burn.

I took his mention of "incident" to mean that something bad actually happened as a result. I don't believe it's uncommon for recreational air divers to accidentally get set up on (or even dive) a nitrox tank but I'm not aware of any injuries or deaths as a result of it. I'm not talking about tech divers using special mixes that are critical to their profile.

 

[Gone for diving]

Dumb question?
Do all nitrox divers have there own tester?
I mean if they get it done in the store, go home, put it in there line up of tanks
Forget... then grab a tank and go diving.... it doesn't get tested before they dive...

 

[formernuke]

Dumb question?
Do all nitrox divers have there own tester?
I mean if they get it done in the store, go home, put it in there line up of tanks
Forget... then grab a tank and go diving.... it doesn't get tested before they dive...

Not all it is recommended but not required.

When I did OC nitrox I would analyze at the shop (required by all shops here) fill out the shop log, label the tank and go home. After diving I would get it filled a re analyze and re label.

Right now all my tanks have labels, but now I have tanks with high O2 levels which means limits on how deep they can be used along with trimix and 100 percent oxygen. Anytime any tank get refilled it gets re analyzed and re labeled.

 

[Belzelbub]

Thanks folks. You have given me what I was after. I trust the fill by the way.

Why do you trust the fill? The only way I'd trust a fill is if I analyzed it myself, witnessed the analysis, or got it filled at a place where air was the only option. Otherwise, there's no way to tell what's in it.

And based on what I see here and the info I’ve seen online I could dive these like they were air at max depth of 40. BUT I think I’ll go ahead and get my enriched cert. I’ve been looking for something to do. Might as well do this

Yep. That's a good idea. EAN really should be included with OW as it's pretty widespread today and doesn't contain any new diving skills.

 

[boulderjohn]

Do all nitrox divers have there own tester?

Very, very few, Mostly they reply on analyzers supplied by the dive operator or the people who filled the tanks.

On a recent trip to Fiji, I went with two different operations. In the first, the analysis process was extreme. They provided the analyzer, but we had to mark every possible piece of information on a sticker on every tank we used. In the second, they wanted us to accept the analysis (32%) on a tag that was obviously permanent. We insisted on doing our own analysis. It was usually within a % or two of 32%, but it was rarely 32%.

 

[scubayinzer412]

Not all it is recommended but not required.

When I did OC nitrox I would analyze at the shop (required by all shops here) fill out the shop log, label the tank and go home. After diving I would get it filled a re analyze and re label.

Right now all my tanks have labels, but now I have tanks with high O2 levels which means limits on how deep they can be used along with trimix and 100 percent oxygen. Anytime any tank get refilled it gets re analyzed and re labeled.

when i get my bottles refilled, i analize them and put a sticker with the % on