Getting nitrox certified...

[Captain CaveMan]

so will i joe.(diving dry) maybe after the classes we can go far a dive???? if im there im going to take advantage of it.

 

[gangrel441]

I'll be out at Haigh on the 23rd as well, doing what I can to assist an OW class. If I do any of my own diving that day, my regular buddy won't be present, so I'll be looking to buddy up. Any takers?

 

[PerroneFord]

I am of two minds here. I will take my Nitrox class in a couple of weeks. I am going back and forth between SSI and IANTD. I have been out of the dive game for a while, and have been practicing to get ready. I have a pretty good understanding already of mixed gasses, partial pressures (not from a blending perspective yet), OTUs, and CNS%. I think I'll do ok.

I am lucky in that I live in an area where diving is viable all the time. One reason I am intersted in taking the Nitrox class without the dives is because *I* want to dictate my dives. I don't want some yahoo telling me in order to take nitrox class, I need to jump off a boat in 100ft of water to understand MOD and EAD. I don't intend to do any diving for the next 6-8 weeks that is below 50ft. And honestly, I am not interested in having someone in a class tell me I need to.

To be honest, the only reason I am taking Nitrox in the first place is so I don't have to fill with air any more. I want to move all my diving to EAN or Mix, or even Triox depending on costs.

Gotta crawl before I walk though.

 

[StSomewhere]

When I did my IANTD Nitrox class there was a written exam and a practical exam. The practical exam went something like this:

First thing tomorrow morning you are going out on a boat for a two tank trip, probably to x wreck and y reef, but **** happens so if the captain has to pick an alternate site the depths may vary slightly (+/- 15'). Knowing what you now know, on your own and without any coaching, order two appropriate EAN mixes, analyze them and mark them. Now, realizing oxtox would probably be fatal, actually go make two dives on those tanks. Its not so much about the dives, per se, its the gravity of the situation. And the instructor can see if you "get it" or if you are totally inept.

FWIW, since then I've discovered that EAN32 gives you most of the benefits of any other recreational nitrox mix, plus its standardized which makes it easy to find banked -- even where I live.

 

[Sideband]

I'll be out at Haigh on the 23rd as well, doing what I can to assist an OW class. If I do any of my own diving that day, my regular buddy won't be present, so I'll be looking to buddy up. Any takers?

You can join us. I don't mind a third if the Captain is up for it. Besides, the shop has a history of throwing in an extra class on me at the last minute so if I end up doing an advanced class in the afternoon the two of you can buddy. No mention of a second class yet though.

Joe

 

[Captain CaveMan]

sweet that would be great, all dry and all on nitrox. man we could stay down for ever. :fruit:

 

[Blackwood]

The important thing to learn in a Nitrox class outside the applied algebra is how to properly analyze a tank.

Unless the standards have changed in the past couple of months, IANTD Nitrox still requires two Nitrox dives.

They are suggested, but not required.

Many IANTD instructors will refuse to certify until they see you dive, as they should.

Requiring two dives makes no sense to me. The course is mostly academic with a few practical skills such as the O2 check and checking the checker..

If someone can explain why there is a NEED for two dives, I'd like to hear it. Again, if you say it's because you're evaluating diving skills.. well then, that should have been done in another training segment. If I'm paying to learn about nitrox, that's that I want. Now if you're (the instructor) are willing to dive teach me something new I'd be OK with it, but again, that is outside the scope of learning about nitrox. Am I missing something? If so, please explain it to me.

Is SDI the only one not requiring the two dives?

Because when you are diving with Nitrox, you worry much sooner about CNS O2 Toxicity. Someone may have great classroom skills and pass all those tests with no problems. But if they are unaware when they get in the water, or if they can't control their depth, etc., they are going to run into trouble.


As Rick mentioned, these are Nitrox DIVER certifications. I can walk in to an average high school algebra class and teach all the Nitrox theory.

 

[Blackwood]

FWIW, since then I've discovered that EAN32 gives you most of the benefits of any other recreational nitrox mix, plus its standardized which makes it easy to find banked -- even where I live.

If you are bringing only one tank on, say, a boat that doesn't fill Nitrox, it is nice to bring EAN40 abord and have the boat top it off with air after each dive. Every top-off will yield a slightly leaner Nitrox mix.

It's easy to calculate the subsequent blends, but it's better to bring an analyser.

 

[timle]

If you are bringing only one tank on, say, a boat that doesn't fill Nitrox, it is nice to bring EAN40 abord and have the boat top it off with air after each dive. Every top-off will yield a slightly leaner Nitrox mix.

Not sure what different certification bodies say but that would definately be against PADI recommendations for enriched air handling. They require a dedicated cylinder for enriched air and if you have it filled with a conventional air filling rig you will need to have it cleaned and inspected.

So who fills the cylinder back up with EANx40 for you after discovering the mix is no where near that?

I'm a complete newbie and just getting my nitrox certification, not trying to be difficult, just curious.

 

[in_cavediver]

Not sure what different certification bodies say but that would definately be against PADI recommendations for enriched air handling. They require a dedicated cylinder for enriched air and if you have it filled with a conventional air filling rig you will need to have it cleaned and inspected.

So who fills the cylinder back up with EANx40 for you after discovering the mix is no where near that?

I'm a complete newbie and just getting my nitrox certification, not trying to be difficult, just curious.

This practice is actually quite common. Simply put, if the tank is not O2 clean now (and it doesn;t need to be for 40%), why not top up a rich mix into a not so rich mix. The math is algebra but you should confirm it with an analyzer (they are cheap enough). The cylinder is already dedicated. The only concern is to not equalize the nitrox tank with air tanks in the filling process. That shouldn't be an issue so no problem.

The concern would be if you partial pressure blend and then, if the top off fills are not modified grade E air, then you 'could' be out of luck on the next fill. Notice I said could. There are no laws mandating this or that, just best practices and guidelines.
Contamimation is cumulitve so 1 or 2 'bad' fills likely wouldn't make much of difference if the bulk of the fill were hyperfiltered. YMMV

Mike