Nitrox Question

[spt29970]

Let me add one more thing that people often get confused about with Nitrox. It doesn't reduce narcosis at depth. There is good research that suggests that at any given depth you get just as narced diving Nitrox as you do with Air, although with the reduced maximum operating depth Nitrox requires, you often avoid narcosis simply by staying more shallow. I read a good paper on this somewhere, but unfortunately it doesn't seem to be online. There is an abstract for a relevant article at Rubicon Research Repository: Item 123456789/7316.

 

[bleeb]

Below are a few links you will find helpful

Couv

Nitrox FAQ
DIR-diver.com - Nitrox Class Part 1
DIR-diver.com - Nitrox Class Part 2

Also, you might want to have a look at ScubaBoard's very own thread: Nitrox instead of air for lower DCS risk

Why take a class? To learn about the dangers of diving oxygen-enriched gases, which can be toxic above certain concentrations. Oxygen toxicity is very dangerous, and it's important for a diver to understand what it is and how to calculate the safe range in which to use any Nitrox mix. That also helps a diver understand why it is so important to analyze your own gas before you take it underwater.

Also covered in many classes is learning to use a gas analyzer, and possibly the differences in technique between models.

 

[lmorin]

Not to get off-topic, but I have to ask. Where does one find these inexpensive nitrox classes? I've been looking and looking, and the best prices I've seen are still around 2/3 the cost of OW or AOW. I mean, my drysuit class, including drysuit rental, was HALF the price of a nitrox class. That's the ONLY reason I don't have a nitrox certification yet.

My wife and I paid $90 each at our LDS. That included the classes and book. As I understand it, some Nitrox certifications require dives to go along with the classwork. That would significantly increase the price.

As for benefits, a correlate of the advantage of shorter surface intervals is decreased overall nitrogen load across days. That is the primary reason we use Nitrox on multi-dives/day x multi-day dive trips, especially given that the residual nitrogen load, and any effects related to the repeated dives across days, tie in with the time-to-fly issue.

 

[ScubaDocER]

My wife and I paid $90 each at our LDS. That included the classes and book. As I understand it, some Nitrox certifications require dives to go along with the classwork.

ALL Nitrox classes should require dives to go along with the classwork. If you have not dove breathing Nitrox then you should not receive a Nitrox certification card.

 

[Walter]

True, but most agencies give them out without dives. SEI doesn't, but I can't name another off the top of my head.

 

[ScubaDocER]

True, but most agencies give them out without dives. SEI doesn't, but I can't name another off the top of my head.

That's very disturbing. Not sure I understand the philosophy behind that. I understand the importance of the academic aspect of Nitrox, but to not require at least 1 dive breathing Nitrox with a certified Instructor, and then hand someone a Nitrox card that allows them to get a fill up to 40% is concerning to me.

 

[Miller64]

SSI requires a dive,,take the class and it can be taken as one of the OW cert dives

 

[Xaryo]

When I took my Nitrox Cert., there wasn't dives included, just theory, exam, gas analysis and the card. But, I did my first Nitrox dive (in fact, all my nitrox dive so far) with an instructor who happen to be my buddy at the time. So I guess that I had dive with my certification.

 

[Damselfish]

I took it when they still required dives, but I think the dives are quite unnecessary for a basic Nitrox cert.

 

[ScubaDocER]

I took it when they still required dives, but I think the dives are quite unnecessary for a basic Nitrox cert.

For the purpose of this post I will assume that Nitrox is a mixture of nitrogen and oxygen where the oxygen content is greater than air.

Diving with Nitrox injects several new factors for the diver unfamiliar with it to deal with. The concept of a MOD that is taught in theory should be understood and appreciated in the water. Multitasking is a great educator in this endeavor. Can you maintain an awareness of your MOD if you are involved in handling many different tasks? If your computer dies and there is no beeping sound to warn you that you are violating your MOD? If you are searching for a lost buddy? If you are taking a picture of that fish you have been chasing for the last few minutes? If you develop a leg cramp?

Have you actually analyzed your tank after the blender just filled it? Were they correct? Do you know what you're signing when you sign the log book? Do you carry back up tables in case your computer fails? What is your contingency depth?

These are a few questions that can be addressed during real world experiences. I am sure there are more.

Diving is an active sport. Choosing to participate in different aspects of diving requires a greater sense of awareness. Without having this awareness tested under the eye of a trained Instrutor places you place yourself at an increased risk IMO.

I shudder to think that a Trimix Instructor would hand a student a Trimix card who had not done a single Trimix dive with them. The standards for diving with Nitrox should be no different.