Nitrox!

[buhavis]

I was just wondering, I don't dive nitrox and I was wondering if it's worth it to get it. Everybody says it is, because its safer and you can get more time out of your dives as long as you still manage your air intake. But, How much longer will it let you stay down compared to the normal recreational no decompression limits?

 

[Blackwood]

Look up "equivalent air depth."

The formula is pretty easy. It simply ratios the amount of nitrogen in a given nitrox mix to that of air, and spits out a shallower depth which results in the same nitrogen load. You can use it to compare nitrox to air on your air table.

 

[The Kraken]

"and you can get more time out of your dives " . . . .

That part is a little misleading.

If you're diving to 60 feet and are using a whole tank of gas for that dive, Nitrox won't extend your dive time.

What Nitrox does is sort of fake your body into thinking that you're diving at a shallower depth allowing you stay longer at your desired depth.

Nitrox does not reduce the amount of gas you consume during a dive.

But, anyway, I think it's worth pursuing.

Well, lets see . . .

Doing an 80' dive on air will give you an NDL bottom time of 30 minutes.
Doing an 80' dive on EAN36 (36% O2) will give you an NDL bottom time of 55 minutes.

the K

 

[cooperscuba]

And it isn`t safer if you dive within recreational limits (they`re already very conservative). Technically it`s more harzordous due to the risk of oxygen toxicity (and as narcotic as nitrogen).

As The Kraken says "worth pursuing" though.

 

[UCFKnightDiver]

And it isn`t safer if you dive within recreational limits (they`re already very conservative). Technically it`s more harzordous due to the risk of oxygen toxicity (and as narcotic as nitrogen).

As The Kraken says "worth pursuing" though.

It can make your dives safer, it depends on how you choose to dive it.

 

[cooperscuba]

Indeed, but you can make normal air dives safer by planning them deeper than actual depth (and you get to save on nitrox training and fills). The benefit of nitrox is to extend your bottom time by reducing nitrogen loading, not to make "dives safer".

Studies have shown there is no reduction in the numbers of DCS when diving on Nıtrox compared to air. The safer tagline is usually given by instructors selling nitrox courses, and ill advised divers.

 

[masterof0]

There are a couple of ways to use nitrox to your benefit

1) you can dive nitrox using the same diving times as air as long as you don't exceed the MOD of the mixture you are using. By doing this, you reduce the amount of nitrogen loading in the tissue. By using it this way, you are building in an additional safety factor on top of what is built into your diving profile. Also, by doing this, you reduce your SI requirement for successive dives.

2) you can use it to extend your diving time. I do not have an EAD table at my disposal, but based on what Kraken posted, you can extend your your dive time (NDL) at 80' from 30 minutes to 55 minutes. By doing this, you do no reap the benefits as you did above since the nitrogen loading of air at 30 minutes is equivalent to the nitrogen loading of EAN36 at 55 minutes.

I personally use it to reduce my overall nitrogen loading as I typically dive around the 60 foot range between 30-40 minutes. By using EANx, I have an additional safety factor in case there is an emergency and do have to make a direct ascent. Even though in the back of my mind I am aware of this, I still do my safety stops and do not intend to make a direct ascent unless I have exhausted all other options.

 

[cooperscuba]

There are a couple of ways to use nitrox to your benefit

1) you can dive nitrox using the same diving times as air as long as you don't exceed the MOD of the mixture you are using. By doing this, you reduce the amount of nitrogen loading in the tissue. By using it this way, you are building in an additional safety factor on top of what is built into your diving profile. Also, by doing this, you reduce your SI requirement for successive dives.

Again, studies have shown there is no reduction of DCS for people using Nitrox compared to air within recreational limits. If you want a bona fıde way to buıld a safety factor in to scuba, don`t dive.

 

[Sampa]

Studies have shown there is no reduction in the numbers of DCS when diving on Nıtrox compared to air. The safer tagline is usually given by instructors selling nitrox courses, and ill advised divers.

Could you show us the study in question? If one uses Nitrox with air NDL's, isn't it pretty obvious that the risk of DCS is smaller since one's tissues absorb less nitrogen this way?

 

[cooperscuba]

The main factor affecting DCS is ascent rate, not load levels. If you are diving within recreational limits there is no safety benefit (Okay, unless you are predisposed (?)) to DCS) because the NDL`s are so conservative. Study I`m refering to was by PADI, you can also check with DAN.

Okay, EAN (regarding DCS) is 0.002% safer but that does not factor in oxygen toxicity. So my statement is amended to "EAN is effectively no safer than standard air within recreational limits and more hazardous when taking in to account the risk of oxygen toxicity".