80cu Tank at 800 Feet ????

[speedyal]

How long can you breath of a 80cu tank at like a luxfer al 80 at 800 feet also whats the formula for figuring this out heres what i got

800 divided by 33 = 24

80cu divided by 24 = 3cu

on google i found something that said the average person breaths a quarter of a cu every breath

so based on this i determined at 800 feet a tank would last 12 minutes but that just doesnt seem correct so tell me what im forgetting or messing up on

thanks for any help guys happy diving

 

[parzdiver]

Actually the pressure in Atmospheres is 800/33 + 1 = 25.24, can't forget the air above the ocean, but the other math is okay.

Many divers have a SAC (surface air consumption) rate of between .4 and .8 cuft per minute. Mine in warm Caribbean waters with single tank and dive skin runs about .5 cuft per minute.

So, at .5 cuft per minute, I'd theoretically have six minutes. Assuming everything else was capable of supporting my life..... and you were using something else to get to and from 800 feet.

 

[speedyal]

If this is the case how on gods green earth has anyone made it to 1,000 feet imagine how many tanks youd need how would you carry anough / suspend enough it just doesnt seem feasible

 

[Akimbo]

How long can you breath of a 80cu tank at like a luxfer al 80 at 800 feet also whats the formula for figuring this out heres what i got

800 divided by 33 = 24

80cu divided by 24 = 3cu

on google i found something that said the average person breaths a quarter of a cu every breath

so based on this i determined at 800 feet a tank would last 12 minutes but that just doesnt seem correct so tell me what im forgetting or messing up on

thanks for any help guys happy diving

You must also subtract the bottom pressure plus ~135 PSI from usable tank pressure.

(.445 PSI/Ft x 800') + 135 PSI intermediate pressure is what you can get out of the tank at a high enough pressure to make a second stage demand valve function. That is why we often use 300 Bar/4,351 PSI bailout bottles below 600' in saturation diving. When you loose gas and have to get back to the bell, the answer is not very damn long at all.

 

[flots am]

How long can you breath of a 80cu tank at like a luxfer al 80 at 800 feet also whats the formula for figuring this out heres what i got

You'll also have a ppO2 of more than 5, which give you a really good chance of seizures, on the other hand, you'll also be narced out of your mind, so you probably won't notice them.

I'm hoping this is just a thought game.

flots.

 

[speedyal]

You must also subtract the bottom pressure plus ~135 PSI from usable tank pressure.

(.445 PSI/Ft x 800') + 135 PSI intermediate pressure is what you can get out of the tank at a high enough pressure to make a second stage demand valve function. That is why we often use 300 Bar/4,351 PSI bailout bottles below 600' in saturation diving. When you loose gas and have to get back to the bell, the answer is not very damn long at all.

how would you determine the bottom pressure?

 

[speedyal]

You'll also have a ppO2 of more than 5, which give you a really good chance of seizures, on the other hand, you'll also be narced out of your mind, so you probably won't notice them.

I'm hoping this is just a thought game.

flots.

wouldnt stageing your gas fix this issue ?

 

[UCFKnightDiver]

how would you determine the bottom pressure?

- 800 ft/33ft(1 atm) + 1atm(for ambient atmosphere)= 25ata
- 25ata * 14.7psi(pressure of 1 atmosphere) = ~367psi(bottom pressure at 800ft)

wouldnt stageing your gas fix this issue ?

You would have to stage a ridiculous amount of gas, there is also surfaced supplied air (I think it would work at that depth shrugs I suppose you would just need a hoss compressor)

 

[speedyal]

with a mix containing .06 of oxygen would keep your pp02 levels safe at that depth right ?

 

[Cave Diver]

with a mix containing .06 of oxygen would keep your pp02 levels safe at that depth right ?

Define "safe."

There are also more things to take into consideration than just your PO2 levels longgggggg before you'd hit that depth.