How much air does an LP85 hold at 2400 PSI?

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Lol, the reason the thread isn't 1 page is that "it depends". Where you fill, available funds, and buoyancy characteristics are just some of the factors that may influence your choice. You should understand, though, the US practice of quoting surface air can be misleading. An HP 100 is about equivalent to an LP 85 at the same pressure.
 
Can someone save me the reading of an 18 page thread and just tell a layman if I should be buying LP or HP, if I want as much air as possible in the tank for deep diving ? Thanks.
For “as much air as possible for deep diving” you will want a rebreather. Or else “more than one”. Do you walk to dive or fall out of a boat? Are you tall or short, above or below average strength? Drysuit or wetsuit? Deco or no deco? Traveling or local?
 
I do boat dives, no shore diving and would like to know if for deep diving if i am better off with LP or HP tanks. Thanks.
 
For “as much air as possible for deep diving” you will want a rebreather. Or else “more than one”. Do you walk to dive or fall out of a boat? Are you tall or short, above or below average strength? Drysuit or wetsuit? Deco or no deco? Traveling or local?
No rebreather for me.
fall out of the boat
avg. height. 120 length tanks are a bit long, but doable.
above avg strength
Wetsuit
Deco
Traveling and local diving
 
I do boat dives, no shore diving and would like to know if for deep diving if i am better off with LP or HP tanks. Thanks.
Depends if you can get the HP tanks filled at your LDS.
Some LDS can't fill HP to the max so you end up with a HP tank and LPish fills.

If I were a young diver starting out I'd get HP tanks because both LDS in my area can fill HP.
 
One can also experience the excitement of getting "extra" air by overfilling a LP one of equivalent HP volume.

Burger King recently tried to market a 1/3lb Burger, as an upgrade to the 1/4lb whopper. It failed miserably because people thought they were getting cheated by getting "one less"..... Maybe a 3/9lb Burger will sell.

Slight cost and slight bouyancy differences aside, I cant think of a compelling reason to tell people to choose LP tanks......
 
However, all the 3442 psi HP steel cylinders (although equivalent in size to the LP versions) are actually marketed at true capacity... the HP100 has a true capacity of 101 cf for example.

Which is also inaccurate, but at least it's in the consumers favor.

You should understand, though, the US practice of quoting surface air can be misleading. An HP 100 is about equivalent to an LP 85 at the same pressure.

So is an old steel 72 if one has the nerve for it.
 
Which is also inaccurate, but at least it's in the consumers favor.



So is an old steel 72 if one has the nerve for it.
Just keep the LP 72 fill under the psi rating of the burst disk! Or slug it!
 
I do boat dives, no shore diving and would like to know if for deep diving if i am better off with LP or HP tanks. Thanks.
Unless the cost difference is dramatic, the hp version is always the better choice.
 

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