80cu Tank at 800 Feet ????

[Cave Diver]

Ok so at eight hundred feet we have established id have

My tank would have 3000psi -(372psi+135psi ~int pressure~) so that leaves us with
2493psi of useable pressure at depth

how do i determine how many cubic feet this is ?

Tank volume / working pressure gives you a volume per psi relationship.

AL80 is actually ~78 cft @ 3000 psi.

78 / 3000 = .026 cft per PSI

2493 psi x .026 = 64.8 cft of usable gas.

So your original 80cft has been reduced by approximately 20%

 

[Cave Diver]

Just brain storming out loud: Have Scubaboard moderators ever considered a "product suggestion to manufacturers" forum. Maybe it would help turn some complaints into better products we can all benefit from.

Not to my knowledge. If you'd like to garner some support for that idea, you can start by suggesting it here: http://www.scubaboard.com/forums/suggestions/

For additional information check this thread out as well: http://www.scubaboard.com/forums/suggestions/182427-so-you-want-new-forum.html

 

[speedyal]

Tank volume / working pressure gives you a volume per psi relationship.

AL80 is actually ~78 cft @ 3000 psi.

78 / 3000 = .026 cft per PSI

2493 psi x .026 = 64.8 cft of usable gas.

So your original 80cft has been reduced by approximately 20%

Ok so assuming my sac is 1.0 at 800' it would be 1.0 x 25 = 25

ACR at depth would be 25.0 cu ft per minute

So that leaves us with 64.8 cu ft / 25.0 = 2.5 minutes of air time

whats whats partial pressure threshholds for gases like helium nitrogen etc

 

[speedyal]

Ok so assuming my sac is 1.0 at 800' it would be 1.0 x 25 = 25

ACR at depth would be 25.0 cu ft per minute

So that leaves us with 64.8 cu ft / 25.0 = 2.5 minutes of air time

whats whats partial pressure threshholds for gases like helium nitrogen etc

^^^^^

was the above information i posted correct ?

 

[Akimbo]

Not to my knowledge. If you'd like to garner some support for that idea, you can start by suggesting it here: http://www.scubaboard.com/forums/suggestions/

For additional information check this thread out as well: http://www.scubaboard.com/forums/suggestions/182427-so-you-want-new-forum.html

Give me a few days and let's see how productive the Better SPG thread/project turns out. It may sell the concept or prove it is not worthy. Thanks.

 

[Van Isle]

^^^^^

was the above information i posted correct ?

Yes. What do you mean by threshold? For O2 most folks like to keep it below a partial pressure of 1.6 for resting/deco, and below 1.4 - or even 1.2 - for working. Helium and/or nitrogen fills up the rest, with some folks saying a maximum Equivalent Narcotic Depth of 100' is where you want to be.

 

[speedyal]

Yes. What do you mean by threshold? For O2 most folks like to keep it below a partial pressure of 1.6 for resting/deco, and below 1.4 - or even 1.2 - for working. Helium and/or nitrogen fills up the rest, with some folks saying a maximum Equivalent Narcotic Depth of 100' is where you want to be.

i meant whats the max partial pressure for nitrogen and helium

 

[Cave Diver]

So, Speedyal, what's your current certification level and what is your interest in all these questions?

 

[speedyal]

So, Speedyal, what's your current certification level and what is your interest in all these questions?

OWD and i just didnt really know diving was this awesome till you guys explained the technical side of it there a beautifull science behind diving that i think alot of people are missing out on im sure this is just a slight taste of it is there any facilities to take tech diving here in oklahoma ?


The interest is just from a scientific stand point

 

[Cave Diver]

OWD and i just didnt really know diving was this awesome till you guys explained the technical side of it there a beautifull science behind diving that i think alot of people are missing out on im sure this is just a slight taste of it is there any facilities to take tech diving here in oklahoma ?


The interest is just from a scientific stand point

Yes, there is a lot to technical diving, which is why some of us express concern at the level of questions you ask. As you can probably tell by now, there is a lot more to this than strapping on a couple of extra tanks and jumping in. Many of us have spent tens of thousands of dollars and years of training and diving to get to the level we're at now. The information we've given you is just the tip of the iceberg and no substitute for formal training.

A quick Google search turned up this shop: Pirates Cove Scuba - ContentMain

I know nothing about them and I'm not endorsing them, just giving you a starting place. Before taking any technical classes I urge you to master the basic skills and interview your instructor to make sure they're a good match and their training goals match your own.