When would you use Nitrox? - Printable Version

When would you use Nitrox? - Printable Version

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When would you use Nitrox? - Chris - 03-08-2002

I have a Nitrox capable computer, but when do you need to use it? Can you use it all the time or just on deeper dives? :o

Re: When would you use Nitrox? - MNLakeDiver - 03-11-2002

check out this link for some ansers but be sure to take the class before trying the dive http://www.scubadiving.com/feature/specials/nitrox/

Re: When would you use Nitrox? - brucev - 03-13-2002

I,ve used it for deep dives. but I.ve also used it on a couple dive trips where we were doing multiple dives {around 4 to 6 }and then a night dive just to increse my safty margin

Re: When would you use Nitrox? - lrmoll - 04-23-2002

I am not Nitrox certified but it is my understanding from sources that I have run across that Nitrox is not so much about going deep but about longer down times. Since the oxygen content is increased in Nitrox at what depth do you have to worry about oxygen toxicity? On the other hand I know of people who say they are able to stay down as long as some others on Nitrox

Re: When would you use Nitrox? - lrmoll - 04-24-2002

Quote:I have a Nitrox capable computer, but when do you need to use it? Can you use it all the time or just on deeper dives? :o

You can use it all the time but a fill is more expensive so why would you want to?

Re: When would you use Nitrox? - ccuda - 04-24-2002

You would use Nitrox more often in warm water climates where you wanted to improve your safety and the amount of bottom you can safely spend at depth. It is typically required you stay more shallow because of the oxygen build-up. Typically no deeper than 130ft or even more shallow the more oxygen content. I think most people think of Nitrox in the wrong way. You dive on air right? Air IS Nitrox. You have 20.9% O2, (21% rounded), and 79% Nitrogen. you have limits on your depth and bottom time for the average diver's safety. Same thing with Enriched Air Nitrox. A great place to use Nitrox is liveaboards! 3, 4, 5 dives a day can really wear you down. Building all the excess nitrogen makes you more fatigued, you increase your DCS chances, and degrease the amount of bottom time for your sequential dives. Improving your vacation value is by doing the dives on Nitrox. (And for locally, most store who offer air filss are around $5-6, Nitrox is usually $10-12.) An example, according to most recreational standars, you have a max bottom time of 55 minutes at 60 feet on air. With a 36% blend, you can spend 115 minutes, that is a huge consideration if you are returning to that depth again for your next dive, or you are doing multiple dives, or want to get the most out of just one dive. (Some can make a tank last longer than others.) It's nice to have the training under your belt, as if your on vacation, some places offer unlimited Nitrox use for their packages or at a fee. Maybe $75-100 more. If you are going to remain within the standrard recreational limits (130fsw), then there isa no reason to ever dive air again on those dives. Nitrox is safer, more healthy, as you are packing more partial pressure of O2 along the hemoglobin in the bloodstream which flushes more nitrogen (a useless gas for the body) from your system that straight compressed air. That'a also why some of us use it even after deeper dives on a safety stop, it's a big benefit! Locally, it's not as much benefit because few of us spend 4 dives in the water without the cold creeping in, but it's a great futue potential if you have the Nitrox background. And for those of us who want to explore the realm of Rebreathers, Nitrox certification is a pre-requisite.

Re: When would you use Nitrox? - Chris - 04-24-2002

CCUDA, Thanks for the excellent information. That really helped me understand its advantage and when to use it for the most benefit. I can see now that it's not something I'll need for a dive at Square Lake, but on the trip we're going on next Winter it would be very useful.

Re: When would you use Nitrox? - lrmoll - 04-24-2002

Any comments about the need of Nitrox capable and cleaned reg's?

Re: When would you use Nitrox? - ccuda - 04-25-2002

For O2 cleaned regs, etc. There's lots of debate. But if you are going to use any mix OVER 40% in either a tank, regulator, spg, or anything connected to high pressure, it needs to be O2 cleaned! And then you should only have your high pressure air sources filled from a highly filtered, NON-Oil lubricated compressor (many shops do not have these, Expense) The tech community and those using higher O2 hang-bottles, etc, always have their gear O2 cleaned. It's not cheap, but neither is tech diving. The debate goes for the 40% and under mixtures. Many manufacturers highly suggest the use of at least Viton orings, oxygen compatible seats and oxygen compatible lubricants, ie Christolube, etc. Some metals are not as compatible with Nitrox as others, for example Titanium. There are many alloys of Titanium. (Titanium regs should not be used for Nitrox without the proper seats, oring, lubs, etc. and then ONLY up to 40%! Some manufacturers use viton orings, seats, and lubricants straight out of the box, ie Scubapro. All good from air to 40% without changes. Others offer upgrade Nitrox kits, ie Sherwood, etc. These cost you more, but then you have more safety to go back and forth between air and Nitrox without being in the "gray zone" of safety. (Nothing in life is perfectly safe). And when you purchase most regs, they are not usually set with the viton orings, etc, but when you service it, you can always ask for them. (Though some manufacturers don't make Nitrox components for the regs, etc. so try to avoid those, you limit your future flexibility) Also, if you are diving Enriched Air Nitrox, tell your service center you are, and then they should be using only oxygen compatible lubricants on your regulator. Many people out there are not aware of the potential for fire because bits of dirt and oil cling to the areas of the reg. You go up North, get you air filled from a guy in his garage (filtered well? maybe yes, but how well, and what lubricant?), then later you put your reg onto a 36% mixture and you are forcing high pressure, higher oxygen content across a dirty surface area. There is a potential for the dirt, oils, etc to cause a spark issue. Put a spark and O2 together and strap it on your back...crispy critter. If you have O2 compatible components and lubricants in your REGULARLY SERVICED reg, and you are NOT using mixtures OVER 40%, then you are good-to-go for having a great time with air and/or Nitrox.

Re: When would you use Nitrox? - tpscuba - 05-23-2002

Quote:I have a Nitrox capable computer, but when do you need to use it? Can you use it all the time or just on deeper dives? :o

Nitrox does extend bottom time,but on shallow dives(those under 40 ft.) you'll use up your air before your time. I find it usefull on dive vacation where you are doing multiple dives over multiple days, I don't seem to feel as runned down as I do on air. As far as depth it depends on the percent of the mix. Having a clean reg for nitrox is wise espicially if you are running 40 % or higher.