Does Nitrox kill brain cells?

[muddiver]

As a newly minted PADI Nitrox diver I dove my first mix dive on the word of teh shop that supplied the tank over in Kaui.

Now having gone through more through education I just carry one of these and an analizer for the tank:

No need for the equation, this chart covers MOD, PO2 and Equivilant Air Depth.

 

[mikemill]

In other parts of the world, do they teach displaying the O2% and the MOD on the tank with duct tape or a pre-printed label?

I know that's in the training strandards but I also know that I've never seen that done on the live-aboards I dove in the Bahamas. I usually see even recreational divers here in North Florida do that but it might be just because they see the tech divers doing it... I'm not sure.

That's the main reason I see for the MOD calculation, to make the your label for the tank and to fill out the log in the fill station. Do other parts of the world have you do that?

I was trained to write the date I analyzed the mix, the % O₂, and the MOD on the piece of tape and then initial it. The MOD is either calculated using the formula or more often by looking it up on the table. The dive shop has a calculator with the formula already programmed in and tables there. Unless don't know the site or I know that the difference between the table's MOD and calculation will make a difference I just use the table.

My dive computer does the MOD calculation for the % I put in plus 1% (i.e. I put in 32% it'll run the MOD calculation for 33%). I'm more likely to follow that then what I put on my tank.

Now on one of the boats here that does onboard fills of banked nitrox I don't do the tape thing. But I still do the rest (analyze, calculate, etc). When I was in Roatan after the first few days I stopped writing all the data on the tape. It was always 32% so I'd just write down the % and initial it. At that point I knew the depths and I had analyzed it that day or the night before.

 

[psychocabbage]

I was taught it. Did not memorize it..

I have computers that do that sort of thing for me... add to it the higher cost of Nitrox everywhere we dive and its not worth it.. Its a novelty cert for us now. I would like to dive it more often but just dont see it being worth the added expense currently.

 

[vtxkev]

To be honest I do not remember the formula off the top of my head, but I know where I have it written down so I can use it for fills. I dont trust anyone or anything other then myself because if something were to happen only I can be blamed. Maybe I am paranoid or maybe I am just very cautious but it is what it is.

 

[Cave Bum]

The main reason for doing the MOD calculation is to let the diver know what is their maximum depth is. The only reason I can see for making a tank label is if you are not going to use that tank right away.

One concept for the use of the label is to put it just below the valve and opposite the way the valve faces so that your buddy can see it when they are slightly behind and above you. This way if they see going below your MOD they can let you know.

 

[tomboyy]

I was taught it. Did not memorize it..

I have computers that do that sort of thing for me... add to it the higher cost of Nitrox everywhere we dive and its not worth it.. Its a novelty cert for us now. I would like to dive it more often but just dont see it being worth the added expense currently.

I have the formula posted at my work station, my LDS requires everyone to measure their tanks to make sure they got what they asked for and to calculate and tag it before they leave.

I use a computer but I still want to plan my dive and my MOD before I jump.

 

[SparticleBrane]

Somewhere in here I'm betting there's an argument for standardized gasses...

 

[AzAtty]

I don't memorize the formuale for MOD, END, etc. per se. I understand the concept embodied by each formula, and if I need to use it, I just derive it on the fly. Kind of like the general gas law--I memorize it and derive the other laws from it.

 

[boulderjohn]

I have taken two nitrox courses and teach one the two. The formula is on the exam for each one.

Do students memorize it? I doubt that many do. As has been pointed out, the MOD is readily available to people, either on a chart or on a computer screen. With the answer to a question staring them in the face, not too many people are going to do the math to check, especially if it is the 80th time using EAN 32.

From the quoted response of the poster that spurred this thread, I assume he was just making a joke and felt no need to do any real calculations to make sure his joke was mathematically correct.

As for practices around the world, I have dived with nitrox in quite a few places, and I have seen a very wide range of practices. In a large percentage of the dives I have done in resort areas, divers tested their tanks while setting up my gear and preparing to enter the water, and no one slaps a tag on the tank at that point.

When I am diving locally on nitrox with friends, we blend our own using partial pressure, and we absolutely do use stickers with the % and MOD in big letters.

 

[Captain12Pk]

I learned the formula and I use the formula. I live, and plan to continue to live by the formula. I also check my tanks at the shop... with my own analyzer. I also re-check my tanks with my analyzer as part of my pre-dive check.