NITROX for any and all dives?

[wildbill9]

Extends bottom time how? A 80 cf tank has x number of breaths depending on your depth. Are you saying you take fewer breaths with nitrox? I doubt that. So how can nitrox extend your bottom time?

 

[Centrals]

Extends bottom time how? A 80 cf tank has x number of breaths depending on your depth. Are you saying you take fewer breaths with nitrox? I doubt that. So how can nitrox extend your bottom time?

What is the ndl for air and Nitrox 32 at 30m(100ft) respectively?

 

[tursiops]

Extends bottom time how? A 80 cf tank has x number of breaths depending on your depth. Are you saying you take fewer breaths with nitrox? I doubt that. So how can nitrox extend your bottom time?

You are limited in your BT by one of two things: amount of gas in the tank, and your nitrogen uptake. If it is the nitrogen uptake ("NDL") that is limiting your dive, then using Nitrox instead of air gives you more time. Those with good gas usage diving to greater than 60 ft or so will often find they are NDL limited, not gas limited. Nitrox helps them.

Was that your question?

 

[wildbill9]

25 min on air, 30 min on nitrox. Problem is there is not enough gas either way to stay down that long without running out of air. Your limit is a factor of gas in the tank, not what is in it.

 

[tursiops]

25 min on o2, 30 min on nitrox. Problem is there is not enough gas either way to stay down that long without running out of air

Do you mean air instead of O2? Are you quoting NDLs from the PADI RDP for 100ft? Let's see: 100 ft is 4 ATM, so a SAC of 0.5 cuft/min would be 2 cuft/min at 100 ft. You are still NDL limited on air, Nitrox 32% mitigates that limitation.

 

[tomfcrist]

If you are serious wild bill, find it disturbing.

 

[bladder]

There is irrefutable evidence that raising the level of oxygen in the blood increases physical performance and increases the rate of healing from injury.

I bet you read that on the internet!

 

[BRT]

Not so. This membrane system give ~93%


Philips - UltraFill Home oxygen system

At some output level medical oxygen concentrators can do that. They use molecular sieves. Nitrox membrane systems don't
Membrane method of gas concentration - Wikipedia
Nuvair says 40% Nitrox Membrane Systems | Nuvair

 

[BRT]

I fill my tires with 78% nitrogen, then wait till the oxygen leaks out, i have 95% nitrogen, top of with more 78%. Soon i have full 95%



I have analyzed the oxygen content in my tires after a month, usually below 7%

Yep. But the tire dealer doesn't make anything and you don't get green valve caps so people know you are environmentely sensitive.

 

[Steve_C]

Extends bottom time how? A 80 cf tank has x number of breaths depending on your depth. Are you saying you take fewer breaths with nitrox? I doubt that. So how can nitrox extend your bottom time?

For one, in many areas the most common tanks are not 80s. HP 100s are very common in my area and is what I dive. Some folks take fewer breaths per minute than other folks. All I know is that with Nitrox many of my dives are NDL limited especially the second dive. Without Nitrox I would be cutting the dives shorter.