Diving shallow on Nitrox.

[redacted]

I dive nitros when it is free or when it is necessary for my planned dives.

 

[RyanT]

Short answer, for a normal recreational dive, you won't see any benefit of nitrox at 20'. I much prefer to dive nitrox for most of my dives (virtually always deeper than 50'), but for 20', I'd happily take air anyday.

 

[gr8jab]

What about those that are on a diving vacation, and slamming 4 tanks/day? Wouldn't 32% help with residual nitrogen loading over multiple repetitive days of diving?

 

[Lorenzoid]

What about those that are on a diving vacation, and slamming 4 tanks/day? Wouldn't 32% help with residual nitrogen loading over multiple repetitive days of diving?

All dives to 20 feet?

 

[kelemvor]

If the calculator here is accurate, and you spent 90 minutes at 20 feet (I did a dive like that this past Sunday hunting fossils), did a short 15 minute SI to swap tanks, you'd only have 29 minutes left of NDL for dive2 at 20 feet.

Dive Table Calculator

I didn't check it against anything else.

I did my dives on ean32, and had a computer. No idea how it would work out on a table, but after 3 of them (the longest underwater day I've ever had, actually) I am pretty sure my NDL was at 99 (max petrel will show). I'll have to go look at the log now...

 

[Nikole]

Ralph - How many divers asking this kind of question IN THIS SECTION know what 18/45 is? Just saying...

LOL exactly I had no idea what he was talking about. I'm not advanced or a tec diver. AND was hoping that someone who actually does beach and spring dives on Nitrox would actually answer. I have asked a few people why nitrox... One agreed with the placebo effect, the other didn't really give me a straight answer he just said because he gets longer bottom time. But dude, we're diving together, I not at a max of 25' and you're only doing a 1 tank dive.

 

[EricTheDood]

I've been on a few beach and shallow spring dives over the summer and have seen this.

Folks who own nitrox tanks will sometimes top them off with air. So what was originally EAN32 might be diluted, e.g. EAN26.

Also, DCS isn't an exact science. Those who are prone to DCS, either through past experiences, certain health issues, or hypochondria, would rather use Nitrox 100% of the time than risk DCS.

One thing to consider is that oxygen free radicals may contribute to cell aging. So is it detrimental to breathe higher pp02 than necessary? Hard to say.

 

[MaxBottomtime]

If the calculator here is accurate, and you spent 90 minutes at 20 feet (I did a dive like that this past Sunday hunting fossils), did a short 15 minute SI to swap tanks, you'd only have 29 minutes left of NDL for dive2 at 20 feet.

It's penalizing you for the short SI. If you sat out an hour you would have 57 minutes of NDL for the second dive.

 

[Nikole]

I've just taken the course, my book says although enriched air reduces the amt of nitrogen you breathe it does not significantly reduce narcosis. Because theoretically oxygen has the same narcotic potential as nitrogen... The current thinking is that the narcosis potential is the same.. And you should plan an enriched air dive accounting for narcosis just as you would regular air. Your susceptibility can change from one dive to the next. My dive instructor is older so he chooses to just dive at a lower PO2 partal pressure..if he dives nitrox (talking deeper dives.. Not 20 ft dives lol) Just for preference.

 

[Caveeagle]

I've just taken the course, my book says although enriched air reduces the amt of nitrogen you breathe it does not significantly reduce narcosis. Because theoretically oxygen has the same narcotic potential as nitrogen... The current thinking is that the narcosis potential is the same.. And you should plan an enriched air dive accounting for narcosis just as you would regular air. Your susceptibility can change from one dive to the next. My dive instructor is older so he chooses to just dive at a lower PO2 partal pressure..if he dives nitrox (talking deeper dives.. Not 20 ft dives lol) Just for preference.

I have heard this, but your body metabolizes some % of the o2, where as the n2 builds up. I understand planning for Narcosis the same, but I am still skeptic on this.